User manual | ER Mapper

ER Mapper
Customization Guide
September 2008
This space reserved for graphic.
Left and right bleed.
Copyright © 2008 ERDAS, Inc.
All rights reserved.
Printed in the United States of America.
The information contained in this document is the exclusive property of ERDAS, Inc. This work is protected under
United States copyright law and other international copyright treaties and conventions. No part of this work may be
reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and
recording, or by any information storage or retrieval system, except as expressly permitted in writing by ERDAS, Inc.
All requests should be sent to the attention of:
Manager, Technical Documentation
ERDAS, Inc.
5051 Peachtree Corners Circle
Suite 100
Norcross, GA 30092-2500 USA.
The information contained in this document is subject to change without notice.
Government Reserved Rights. MrSID technology incorporated in the Software was developed in part through a
project at the Los Alamos National Laboratory, funded by the U.S. Government, managed under contract by the
University of California (University), and is under exclusive commercial license to LizardTech, Inc. It is used under
license from LizardTech. MrSID is protected by U.S. Patent No. 5,710,835. Foreign patents pending. The U.S.
Government and the University have reserved rights in MrSID technology, including without limitation: (a) The U.S.
Government has a non-exclusive, nontransferable, irrevocable, paid-up license to practice or have practiced
throughout the world, for or on behalf of the United States, inventions covered by U.S. Patent No. 5,710,835 and has
other rights under 35 U.S.C. § 200-212 and applicable implementing regulations; (b) If LizardTech's rights in the
MrSID Technology terminate during the term of this Agreement, you may continue to use the Software. Any provisions
of this license which could reasonably be deemed to do so would then protect the University and/or the U.S.
Government; and (c) The University has no obligation to furnish any know-how, technical assistance, or technical data
to users of MrSID software and makes no warranty or representation as to the validity of U.S. Patent 5,710,835 nor
that the MrSID Software will not infringe any patent or other proprietary right. For further information about these
provisions, contact LizardTech, 1008 Western Ave., Suite 200, Seattle, WA 98104.
ERDAS, ERDAS IMAGINE, IMAGINE OrthoBASE, Stereo Analyst and IMAGINE VirtualGIS are registered trademarks;
IMAGINE OrthoBASE Pro is a trademark of ERDAS, Inc.
SOCET SET is a registered trademark of BAE Systems Mission Solutions.
Other companies and products mentioned herein are trademarks or registered trademarks of their respective owners.
Table of Contents
Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Using the ER Mapper library . . . . . . . . . . . . . . . . . . . . . . . . 3
Windows applications . . . . . . . . . . . . . . . . . . . . . . . . . 3
Linking to MSVCRT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Adding support for new file formats . . . . . . . . . . . . . . . . . . . 5
File Syntax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Data and processing files . . . . . . . . . . .
Data files . . . . . . . . . . . . . . . . . . . . . . . . .
Dynamic link specifications . . . . . . . . . . . .
Processing and configuration files . . . . . . . .
Common elements of ER Mapper files . . . . .
.
.
.
.
.
. . . . . . .
........
........
........
........
.
.
.
.
.
. .7
.. 7
.. 8
.. 8
. 10
An example file . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Integrating data with ER Mapper . . . . . . . . . . . . . . . . . . . . 15
Introduction . . . . . . . . . . . . . .
ER Mapper Raster File format . . .
ER Mapper Vector File format . . .
Dynamic Links . . . . . . . . . . . . .
Vector images and Dynamic Links
Open Standards . . . . . . . . . . . .
Testing . . . . . . . . . . . . . . . . . .
Looking ahead . . . . . . . . . . . . .
. . . . . . .
........
........
........
........
........
........
........
.
.
.
.
.
.
.
.
. . . . . . .
........
........
........
........
........
........
........
.
.
.
.
.
.
.
.
. 15
. 15
. 16
. 16
. 18
. 18
. 18
. 18
Supplied Dynamic . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Example Dynamic Links . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Raster Datasets and Header Files (.ers) . . . . . . . . . . . . . . . 21
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
The header file . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
The data file . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
The raster header file . . . . . . . . . . . . . . . . . . . . . . . . 21
DatasetHeader Block . . . . . . . . . . . . . . . . . . . . . . . . . 21
Compulsory entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Optional entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Coordinate Space Block . . . . . . . . . . . . . . . . . . . . . . . 24
Compulsory entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Optional entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
RasterInfo Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Compulsory entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Optional entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
CellInfo Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Table of Contents
iii
Registration Coord Block . . . . . . . . . . . . . . . . . . . . . . 28
BandId Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Compulsory entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Optional entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
SensorInfo Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Compulsory entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Optional entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
FiducialInfo Block . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Fiducial point block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
RegionInfo Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
WarpControl Block . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Correction Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
GivenOrthoInfo Block . . . . . . . . . . . . . . . . . . . . . . . . 36
FFTInfo Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Example dataset header files . . . . . . . . .
Example Landsat header file . . . . . . . . . . .
Georeferenced dataset header file . . . . . . .
Example of a complex dataset header file . .
Raster data file . . . . . . . . . . . . . . . . . . . . .
.
.
.
.
.
. . . . . . .
........
........
........
........
.
.
.
.
.
. 38
. 38
. 39
. 39
. 44
Vector Datasets and Header Files (.erv) . . . . . . . . . . . . . . . 47
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
The header file . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
The data file . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Vector header file format . . . . . . . . . . . . . . . . . . . . . 48
DatasetHeader Block . . . . . . . . . . . . . . . . . . . . . . . . . 49
Compulsory entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Optional entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
CoordinateSpace Block . . . . . . . . . . . . . . . . . . . . . . . 51
Compulsory entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Optional entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
VectorInfo Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Extents Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Example vector header files . . . . . . . . . . . . . . . . . . . 53
Example “RAW” vector dataset header file . . . . . . . . . . . . . 53
Vector data file . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Dynamic Links Program Interface . . . . . . . . . . . . . . . . . . . 59
Introduction . . . . . . . . . . . . .
Non-Raster data . . . . . . . . . . .
ER Mapper PostScript . . . . . . .
Editable links . . . . . . . . . . . . .
Flexible connections . . . . . . . .
Multiple links . . . . . . . . . . . . .
Ready-made links . . . . . . . . . .
Triggering links . . . . . . . . . . .
Examples . . . . . . . . . . . . . . . .
iv
.
.
.
.
.
.
.
.
.
. . . . . . .
........
........
........
........
........
........
........
........
.
.
.
.
.
.
.
.
.
. . . . . . .
........
........
........
........
........
........
........
........
.
.
.
.
.
.
.
.
.
. 59
. 59
. 59
. 59
. 59
. 59
. 59
. 59
. 59
Table of Contents
Georeferenced and Page Relative layers
Georeferenced data . . . . . . . . . . . . . . . . .
Page relative layers . . . . . . . . . . . . . . . . .
Dynamic Link layer buttons . . . . . . . . . . . .
Inside a Dynamic Link . . . . . . . . . . . . . . . .
.
.
.
.
.
. . . . . . .
........
........
........
........
.
.
.
.
.
. 60
. 60
. 60
. 60
. 62
Creating a Dynamic Link . . . .
ER Mapper PostScript . . . . . . .
Looking ahead . . . . . . . . . . . .
Adding the menu option . . . . .
.
.
.
.
. . . . . . .
........
........
........
.
.
.
.
. . . . . . .
........
........
........
.
.
.
.
. 64
. 64
. 64
. 65
Chooser program . . . . . . . .
Name and Directory . . . . . . .
Arguments . . . . . . . . . . . . . .
Output . . . . . . . . . . . . . . . .
Link initialization . . . . . . . . . .
.
.
.
.
.
. . . . . . .
........
........
........
........
.
.
.
.
.
. . . . . . .
........
........
........
........
.
.
.
.
.
. 66
. 66
. 66
. 66
. 67
.
.
.
.
.
Example initialization program . . . . . . . . . . . . . . . . . 69
PostScript generation . . . . . .
Name and Directory . . . . . . . .
Arguments . . . . . . . . . . . . . . .
Output . . . . . . . . . . . . . . . . .
Errors . . . . . . . . . . . . . . . . . .
.
.
.
.
.
. . . . . . .
........
........
........
........
.
.
.
.
.
. . . . . . .
........
........
........
........
.
.
.
.
.
. 70
. 70
. 70
. 71
. 71
Printing dynamic links . . . . . . . . . . . . . . . . . . . . . . . . 72
MONOCOLOUR vs TRUECOLOUR links . . . . . . . . . . . . . 73
Batch Script Chooser . . . . . . . . . . . . . . . . . . . . . . . . . 73
Debugging dynamic lines . . . . . . . . . . . .
Example 1 - Example User Dynamic Link . . .
Example 2 - Table of data shown as circles .
Example 3 - Dynamic Link to ARC/INFO . . .
.
.
.
.
. . . . . . .
........
........
........
.
.
.
.
. 73
. 75
. 78
. 89
PostScript . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Dimensions in pixels . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Variable canvas size . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Defined variables . . . . . . . .
Example . . . . . . . . . . . . . . .
ER Mapper PostScript . . . . . .
Standard Postsript . . . . . . . .
Variable aspect ratio . . . . . . .
Dimensions in points . . . . . . .
.
.
.
.
.
.
.
.
.
.
.
.
. . . . . . .
........
........
........
........
........
.
.
.
.
.
.
. . . . . . .
........
........
........
........
........
.
.
.
.
.
.
. 95
. 96
. 96
. 96
. 97
. 97
Summary of ER Mapper PostScript functions . . . . . . . 98
Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
Performance and accuracy .
Use device DPI . . . . . . . . . . .
Integers not reals . . . . . . . . .
Reduce PostScript file size . . .
Use Monocolour PostScript . . .
Extract current data . . . . . . .
Use ER Mapper coordinates . .
.
.
.
.
.
.
.
. . . . . . . .
.........
.........
.........
.........
.........
.........
.
.
.
.
.
.
.
. . . . . . .
........
........
........
........
........
........
. 100
. 100
. 100
. 100
. 101
. 101
. 101
Using existing PostScript . . . . . . . . . . . . . . . . . . . . 101
ervecmacro.erm . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Table of Contents
v
The ER Mapper Configuration File (config.erm) . . . . . . . . . 103
ERMConfig Block . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
Algorithm files (.alg) . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
Example algorithm file . . . . . . . . . . . . . . . . . . . . . . 105
Algorithm file entries . . . . . . . . . . . . . . . . . . . . . . . 113
Coordinate space block . . . . . . . . . . . . . . . . . . . . . . 115
TopLeftCorner and BottomRightCorner Blocks . . . . . 116
PageSize Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
ThreeDInfo block . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Surface Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Stream Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
StreamInput Sub-Blocks . . . . . . . . . . . . . . . . . . . . . 123
Kernel Sub-Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . 123
Formula Sub-Blocks . . . . . . . . . . . . . . . . . . . . . . . . 123
Transform Sub-Blocks . . . . . . . . . . . . . . . . . . . . . . . 124
Dynamic Link Overlay Entries . . . . . . . . . . . . . . . . . 125
Filter files (.ker) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
C Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
Formula files (.frm) . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
FormulaArg Blocks . . . . . . . . . . . . . . . . . . . . . . . . . 131
BandID Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
C filters and functions . . . . . . . . . . . . . . . . . . . . . . . . . . 135
Filters/kernels . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135
Writing and compiling usercode on PCs . . . . . . . . . . 135
Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135
Setting and referring to Windows environment variables . . 136
Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Example code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
Building new formula and filters manually . . . . . . . . . . . . 137
To edit formula and kernels/filters C source code . . . . . . . 137
To write or build your own formula manually . . . . . . . . . . 137
To write and build your own filter/kernel manually . . . . . . 138
To compile usercode directories (formulae, filters/kernels) 138
To manually compile usercode . . . . . . . . . . . . . . . . . . . . 139
Notes on compiling libermapper programs on PC . . . . . . . 140
Filter file format . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
The filter Object file . . . . . . . . . . . . . . . . . . . . . . . . 143
Formula functions . . . . . . . . . . . . . . . . . . . . . . . . . . 143
C user defined function name . . . . . . . . . . . . . . . . . . . . . 144
Number of Arguments . . . . . . . . . . . . . . . . . . . . . . . . . . 144
vi
Table of Contents
Type of Arguments . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
C function format . . . . . . . . . . . . . . . . . . . . . . . . . . 144
Initialization and finalization . . . . . . . . . . . . . . . . . 145
Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
Formula . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Linking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
Default switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
Special case linking . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
Special C Function arguments . . . . . . . . . . . . . . . . . 147
INPUTVECTOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
USERSTATS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
Creating Color Tables . . . . . . . . . . . . . . . . . . . . . . . . . . 151
To select a Lookup Table . . . . . .
To create a new Lookup Table . .
To generate a linear Color Lookup
Example: a 2-color Lookup Table
.....
.....
Table
.....
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
151
151
151
152
Example: a multicolor Lookup Table . . . . . . . . . . . . 152
Example: assigning specific colors to each grey level . .
152
Look Up Table files (.lut) . . . . . . . . . . . . . . . . . . . . . . . . 155
LUT file entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
Hardcopy files (.hc) . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
Menu and toolbar files (.erm) and (.bar) . . . . . . . . . . . . . 161
Submenus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162
Menu option keyboard selection . . . . . . . . . . . . . . . 163
Option separators . . . . . . . . . . . . . . . . . . . . . . . . . . 163
Available callback options . . . . . . . . . . . . . . . . . . . . 163
Map Composition files (.ldd) . . . . . . . . . . . . . . . . . . . . . . 167
LegendRule block . . . . . . . . . . . . . . . . . . . . . . . . . . 169
UserParameter Block . . . . . . . . . . . . . . . . . . . . . . . . 170
Allowable Parameter types .
Algorithm . . . . . . . . . . . . . .
YES/NO . . . . . . . . . . . . . . . .
String . . . . . . . . . . . . . . . . .
Number . . . . . . . . . . . . . . . .
List . . . . . . . . . . . . . . . . . . .
Color . . . . . . . . . . . . . . . . . .
Font . . . . . . . . . . . . . . . . . .
DynamicLink . . . . . . . . . . . .
.
.
.
.
.
.
.
.
.
. . . . . . . .
.........
.........
.........
.........
.........
.........
.........
.........
.
.
.
.
.
.
.
.
.
. . . . . . .
........
........
........
........
........
........
........
........
. 171
. 171
. 171
. 171
. 171
. 172
. 172
. 172
. 174
Generate Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
AlgorithmImagePS . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
Table of Contents
vii
Progirst . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Linepath . . . . . . . . . . . . . . . . . . . . . . . . . . .
Boundingbox . . . . . . . . . . . . . . . . . . . . . . . .
ScaleBar . . . . . . . . . . . . . . . . . . . . . . . . . . .
Special User Parameter “GeodeticScaleLatitude”
176
ZScale . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
NorthArrow . . . . . . . . . . . . . . . . . . . . . . . . .
Grid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . 174
. . . . . . . . 174
. . . . . . . . 174
. . . . . . . . 175
for scale bars .
. . . . . . . . 176
. . . . . . . . 176
. . . . . . . . 176
PSLibInclude Block . . . . . . . . . . . . . . . . . . . . . . . . . 177
PSExecInclude Block . . . . . . . . . . . . . . . . . . . . . . . . 177
Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178
Dynamic Links . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183
Menu entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183
Submenus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185
Menu entry parameters . . . . . . . . . . . . . . . . . . . . . . 185
To add a Dynamic Link option . . . . . . . . . . . . . . . . . . . . 186
Link chooser parameter . . . . . . . . . . . . . . . . . . . . . . 187
Digitizer files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191
Digitizer type file .dtp . . . . .
Notes . . . . . . . . . . . . . . . . .
Format of .dtp files. . . . . . . .
Calcomp digitizers . . . . . . . .
GTCO digitizers . . . . . . . . . .
Altek digitizers . . . . . . . . . . .
.
.
.
.
.
.
. . . . . . . .
.........
.........
.........
.........
.........
.
.
.
.
.
.
. . . . . . .
........
........
........
........
........
. 191
. 192
. 192
. 193
. 193
. 193
Digitizer configuration file .dcf . . . . . . . . . . . . . . . . 194
Digitizer session file .dig . . . . . . . . . . . . . . . . . . . . . 195
Digitizer modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196
Hardcopy Processing and Filter programs . . . . . . . . . . . . . 197
Hardcopy processing stages . . . . . . . . .
Create device independent output . . . . . . .
Convert to device format . . . . . . . . . . . . . .
Send to device . . . . . . . . . . . . . . . . . . . . .
Strip printing . . . . . . . . . . . . . . . . . . . . . .
.
.
.
.
.
. . . . . . .
........
........
........
........
. 197
. 197
. 197
. 197
. 198
The hardc . . . . . . . . . . . . . . . . . . . . . . . opy engine 198
The hardcopy engine Output Format . . . . . . . . . . . . . . . . 199
Filter Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199
Creating a Filter Program (.c) . . . . . . . . . . . . . . . . . . . . . 199
Color compression . . . . . . . . . . . . . . . . . . . . . . . . . . 209
Dithering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
Image compression . . . . . . . . . . . . . . . . . . . . . . . . . 210
Chroma correction . . . . . . . . . . . . . . . . . . . . . . . . . . 210
Output Program . . . . . . . . . . . . . . . . . . . . . . . . . . . 210
viii
Table of Contents
Subsampling/Supersampling . . . . . . . . . . . . . . . . . . 211
Aspect ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211
Hardcopy output size . . . . . . . . . . . . . . . . . . . . . . . 211
Color . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211
Importing using a command line . . . . . . . . . . . . . . . . . . . 213
Raster and vector image formats . . . . . . . . . . . . . . . 213
Raster File Import Switches . . . . . . . . . . . . . . . . . . 214
Importing
Example
Example
Example
Example
Example
Example
Example
Raster File examples . . . . . . .
1 ........................
2 ........................
3 ........................
4 ........................
5 ........................
6 ........................
7 (importusgs) . . . . . . . . . . . . . .
.
.
.
.
.
.
.
.
. . . . . . .
........
........
........
........
........
........
........
. 216
. 216
. 216
. 217
. 217
. 217
. 217
. 218
Vector File Import Switches . . . . . . . . . . . . . . . . . . 218
Importing Vector File examples . . . . . . . . . . . . . . . . 219
Example 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219
Example 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219
Invert . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219
Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221
Coordinate
togeo . .
fromgeo
gdt_conv
conversion . . . . .
...............
...............
...............
Tape utilities . . . .
erm_tapeutil . . .
tape_struct . . . .
dump_cct . . . . .
tape2disk . . . . . .
disk2tape . . . . . .
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
. . . . . . .
........
........
........
.
.
.
.
. . . . . . .
........
........
........
. 221
. 221
. 221
. 221
. . . . . . .
........
........
........
........
........
.
.
.
.
.
.
. . . . . . .
........
........
........
........
........
.
.
.
.
.
.
. . . . . . .
........
........
........
........
........
. 221
. 221
. 222
. 222
. 222
. 222
Image file compression . . . . . . . . . . . . . . . . . . . . . . 222
ecw_compress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222
ecw_compress_gui . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223
Batch scripting and wizards . . . . . . . . . . . . . . . . . . . . . . 225
Batch script documentation . . . . . . . . . . . . . . . . . . . 225
Creating a batch script . . . . . . . . . . . . . . . . . . . . . . 226
Getting started . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226
Example display and geolinking script . . . . . . . . . . . . . . . 229
Wizard scripts . . . . . . . . . . . . . . . . . . . .
Example wizard script . . . . . . . . . . . . . . . .
The layout of wizard pages . . . . . . . . . . . .
General guidelines for wizard pages . . . . . .
Example wizard . . . . . . . . . . . . . . . . . . . .
Table of Contents
.
.
.
.
.
. . . . . . .
........
........
........
........
. 233
. 234
. 236
. 239
. 240
ix
Scripting language . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247
Input to batch process. . . . . . . . . . . . . .
Command line arguments . . . . . . . . . . . . .
Dialog boxes . . . . . . . . . . . . . . . . . . . . . .
Dialog box input fields . . . . . . . . . . . . . . . .
Wizards . . . . . . . . . . . . . . . . . . . . . . . . . .
Using preferences to remember settings . . .
.
.
.
.
.
.
. . . . . . .
........
........
........
........
........
. 247
. 248
. 248
. 249
. 250
. 251
ER Mapper Objects. . . . . . . .
Image Manipulation . . . . . . .
Actions . . . . . . . . . . . . . . . .
Attributes . . . . . . . . . . . . . .
Command summaries . . . . . .
Preferences . . . . . . . . . . . . .
File and Path separators . . . .
Other commands . . . . . . . . .
.
.
.
.
.
.
.
.
. . . . . . .
........
........
........
........
........
........
........
. 253
. 254
. 257
. 258
. 261
. 277
. 277
. 278
Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Output to image window . . . . . . . . . . . . . . . . . . . . . . .
Output to file . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Output to Batch Engine Output dialog (print commands) .
Warning dialog . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Status dialog . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. 279
. 280
. 280
. 280
. 281
. 281
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
. . . . . . .
........
........
........
........
........
........
........
Library of batch scripts . . . . . . . . . . . . . . . . . . . . . . 282
Scripting reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283
Operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283
Concatenation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283
Mathematical functions . . . . . . . . . . . . . . . . . . . . . . 283
Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284
Arrays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287
Page size options . . . . . . . . . . . . . . . . . . . . . . . . . . 288
Keywords . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 288
Flow control . . . .
Labels . . . . . . . .
Controls . . . . . .
Explicit exit . . . .
Looping . . . . . . .
.
.
.
.
.
. . . . . . .
........
........
........
........
.
.
.
.
.
.
.
.
.
.
. . . . . . .
........
........
........
........
.
.
.
.
.
. . . . . . .
........
........
........
........
. 290
. 290
. 290
. 290
. 291
Including files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 291
Error reporting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 291
Script Commands - Alphabetical listing .
Example . . . . . . . . . . . . . . . . . . . . . . . . .
Examples . . . . . . . . . . . . . . . . . . . . . . . . .
Example . . . . . . . . . . . . . . . . . . . . . . . . .
Example . . . . . . . . . . . . . . . . . . . . . . . . .
.
.
.
.
.
. . . . . . .
........
........
........
........
. 291
. 302
. 305
. 329
. 337
Sensor Platform Characteristics . . . . . . . . . . . . . . . . . . . 359
NOAA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 359
Geoscan MSS Mark 2 . . . . . . . . . . . . . . . . . . . . . . . . 360
x
Table of Contents
IRS-IC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 364
LANDSAT 4 or LANDSAT MSS . . . . . . . . . . . . . . . . . . 367
LANDSAT 5 or LANDSAT TM . . . . . . . . . . . . . . . . . . . 369
LANDSAT 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 372
SPOT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 372
Data suppliers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 377
Australian Centre for Remote Sensing (ACRES) . .
Australian Geological Survey Organisation (AGSO)
Department of Mineral Resources TAS . . . . . . . .
Earth Observation Satellite Company . . . . . . . . .
Eurimage . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GeoImage Pty Ltd . . . . . . . . . . . . . . . . . . . . . . .
Intera Information Technologies Corporation . . . .
Kevron Geophysics Pty Ltd . . . . . . . . . . . . . . . . .
National Geophysical Data Center . . . . . . . . . . . .
RADARSAT International, Inc. . . . . . . . . . . . . . .
Satellite Remote Sensing Services . . . . . . . . . . .
SPOT Imaging Services Pty Ltd . . . . . . . . . . . . .
SSC Satellitbild . . . . . . . . . . . . . . . . . . . . . . . . .
USGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
377
377
377
378
378
378
379
379
379
379
380
380
381
381
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 383
Table of Contents
xi
xii
Table of Contents
Preface
This section contains information for C/C++ programmers interested
in working with the ER Mapper library or in adding to the file formats
that ER Mapper can directly open or save. In particular, it contains
information on linking applications with the ER Mapper library that
will be of use to those developers who wish to update applications
linking with the library.
For more detailed information on any of these topics, please contact
your regional ER Mapper office.
Preface
1
2
Preface
Using the ER Mapper library
The ER Mapper library contains powerful functions for reading and
writing ER Mapper image datasets and algorithms. This chapter
provides information on how to link the ER Mapper library with your
application.
For more detailed information on using the ER Mapper library contact
your regional ER Mapper office and ask them about the ER Mapper
Software Developers’ Kit (the ER Mapper SDK).
Windows
applications
The following is a description of how to set up your project to enable
you to use the ER Mapper library with your application. Note that you
must have the following installed:
•
ER Mapper
•
Microsoft Visual Studio 2005
In the following <ermapperdir> is the directory in which ER
Mapper was installed. This is often C:\Program Files\ERDAS
\ERDAS ER Mapper 7.2.
1. Set up the following environment variables:
ERMAPPER
Should point to <ermapperdir>.
ERM_MACHINE_TYPE
Should be “win32”.
PATH
You need to add <ermapperdir>\bin\win32 to
your PATH variable.
ERMTMP
Should point to a directory which can be used to store
temporary files (optional)
2. Start Microsoft Visual Studio 2005 and load your project workspace.
3. Select Tools->Options from the menu and do the following:
a) Select the Directories tab and then select Library files from the
Show directories for list. Add:
<ermapperdir>\lib\win32
b) Select Include files from the Show directories for list. Add the
following:
<ermapperdir>\include
4. Select OK.
5. Select Project->Settings from the menu.
6. Select Win32 Debug from the Settings for list.
Using the ER Mapper library
3
a) Select the C/C++ tab and add the following to the Preprocessor
definitions field:
,win32,INC_OLE1.
b) Select Code Generation in the Category list and change the Use
run-time library field to Multithreaded DLL.
c) Select the Link tab and add the following to Object/library
modules field:
ermapper.lib wsock32.lib.
d) Select Input from the Category list. To the Ignore Libraries
field add:
libc.lib
7. Select OK.
8. Repeat step 6, but select Win32 Release instead of Win32 Debug
from the Settings For list.
9. Select the Project->Build projectname option from the menu.
The project should now compile and link.
10. To run the examples from within the Visual Studio 2005
environment, select Project->Settings... from the menu, then
select the Debug tab, and then enter your program arguments (if
any). You can then select Build->Execute projectname from the
menu to run the program.
Linking to MSVCRT
4
When you are linking or creating raster translators, you should try to
link with the same version of MSVCRT, and in the same way that
ER Mapper is linked. If your code installs its own instance of MSVCRT
it also creates a second malloc heap. The ER Mapper DLL could then
free up memory allocated by your copy of MSVCRT.
Using the ER Mapper library
Adding support for new file formats
The list of file formats which can be opened or saved by ER Mapper
is extensible through the addition of raster translators which can be
written by anyone. Raster translators are dynamic linked libraries
(DLLs) on Windows systems..
Once written, raster translators must be installed in the
raster_translator directory of the product using the ER Mapper
library. With ER Mapper and ER Viewer, this is the
raster_translators\win32 directory.
Adding support for new file formats
5
6
Adding support for new file formats
File Syntax
ER Mapper has a number of internal files and file formats. You don’t
generally need to know about them because they are transparent
when you use ER Mapper. They are included here for advanced users
and for trouble-shooting. ER Mapper has a policy of open standards
so all formats are included here.
This chapter introduces the file formats including the file extensions
and common elements. Read this chapter first so you are familiar
with the conventions in the rest of the manual, then turn to the
chapter dedicated to the file format you are interested in.
•
Part 1 discusses the different ways of integrating data with
ER Mapper by importing or using dynamic links. The raster and
vector formats and dynamic link specifications are detailed in this
part.
•
Part 2 documents the remaining types of processing and
configuration files that ER Mapper uses.
•
Part 3 gives the syntax for carrying out selected ER Mapper
processing from the command line.
Data and
processing files
ER Mapper files can be divided into two general types: data files, and
processing and configuration files. Data files store the data in
internal raster and vector file formats. Processing and configuration
files define the processing you want to apply and store processing
control parameters.
Data files
ER Mapper has internal raster and vector file formats. In general we
refer to data as though they were kept in individual files. Most of the
time this is how we use them. In reality, however, all data files are
made up of two parts: the data itself and an associated header file.
The data file holds just the data—pixel values for raster data in
binary format and object vertices and drawing information for vector
data in ASCII format. The header file contains information about the
data, for example, how many rows and columns there are, what the
map projection is, etc. Raster and vector data file names do not have
file extensions, their corresponding header files have the same name
as the data file and with ‘.ers’ and ‘.erv’ extensions respectively.
Data files can have a different name to their corresponding header
files as long as data file name is defined in the header file.
File Syntax
File Type
File
Extension
Raster data
none
File Function
Binary raster image data file (requires an
accompanying .ers file). For example,
Australia_DTM
7
File Type
File
Extension
Raster data header
..ers
ASCII (text) file. Identifies characteristics of a
raster image file. For example,
Australia_DTM.ers
Vector data
none
ASCII (text) vector data file (requires an
accompanying .erv file). For example,
San_Diego_Roads
Vector data header
..erv
ASCII (text) file. Identifies characteristics of a
vector data file. For example,
San_Diego_Roads.erv
File Function
ER Mapper can also add a .ers header file to ECW compressed
image data files and to those of other supported formats like
GeoTIFF/TIFF and JPEG.
Dynamic link
specifications
In addition to internal data file formats, ER Mapper can link to
external data formats through its dynamic link capability. This
gateway displays any (properly formatted) PostScript information.
Included with ER Mapper are dynamic links to Geographic
Information Systems (ARC/INFO), databases (Oracle) and external
file formats (.dxf files etc). Links to any PostScript data can be added
using dynamic links.
Processing and
configuration files
ER Mapper stores processing commands in ASCII (plain text) files
which can be easily read and edited. Most of the ASCII files are
created automatically by ER Mapper as you use the Graphical User
Interface to request different image processing tasks. ER Mapper
also uses information in configuration files which are set up to
customize it.
Each of the different file types is distinguished by its file name
extension. They are listed below with a brief description of the
function of each file type.
.
8
File Type
File
Extension
Configuration
config.erm
Holds license details, computer display attributes
etc
Algorithm
.alg
Describes processing tasks to be applied to one or
more input data sources to produce an image
display
Filter/Kernel
.ker
Describes the values for a 2-D filter/convolution
kernel
File Function
File Syntax
File Type
File
Extension
Formula
.frm
Describes a mathematical formula to be applied to
one or more input sources to produce one layer of
an image display
Lookup Table
.lut
Defines the values for a color lookup table
Hardcopy
.hc
Defines the capabilities of a hardcopy device
Menu
.erm
Define the ER Mapper menus
ervecmacro
.erm
Internal Read Only file converts ER Mapper vector
files to PostScript
Batch
.erb
Files written in ER Mapper batch scripting language.
Camera
.cam
Holds camera details required for orthorectification.
Grid Project
.egp
Project File created and used by the Gridding
Wizard.
File Function
Each of the file types is discussed in detail in chapters which follow
in this manual. The remainder of this chapter describes terminology
and structures common to all the ER Mapper files.
File Syntax
9
Common elements of ER
Mapper files
ER Mapper ASCII files are made up of lines of text which specify
parameters. These parameters define characteristics and
processing; some are compulsory, others are optional. Related
parameter entries are grouped together in blocks. The examples in
this chapter refer to a dataset header file but the same block
structure and parameter specification syntax is used in all (nondata) files. A simple example of a dataset header file is given below.
The entries in this file are explained in “Raster Datasets and
Header Files (.ers)” in this manual. For the moment just note the
block structure and parameter specification syntax; these are
explained in the remainder of the chapter.
DatasetHeader Begin
Version = "7.2"
DataSetTypen= ERStorage
DataTypen = Raster
ByteOrder = MSBFirst
CoordinateSpace Begin
Datum = "RAW"
Projection = "RAW"
CoordinateType= RAW
Rotation = 0:0:0.0
CoordinateSpace End
RasterInfo Begin
CellType = IEEE4ByteReal
NrOfLines = 401 # Number of lines
NrOfCellsPerLine= 300 # Number of cells per line
NrOfBands = 3# Number of bands
RasterInfo End
DatasetHeader End
Comment lines
Blank lines are disregarded. The hash (#) symbol identifies a line or
part of a line as a comment. Characters following the ‘#’ through to
the end of the line are ignored. For example, the following line:
Xdimension = 10.0 # the cell size is in metres
will be read by ER Mapper as:
Xdimension = 10.0
Parameter Specification entries
ER Mapper files are made up of parameter specification entries which
assign a value to one of the parameters used by ER Mapper. The
syntax is:
parameter_name = value
For example,
NrOfCellsPerLine = 1000
Projection = "RAW"
10
File Syntax
Parameter Names. Parameter names are usually made up of several
words run together, with the first character of each word capitalized.
This capitalization is to make the parameters easier to read and is
optional. ER Mapper ignores the character case when it processes
the entry lines. For example, NrOfCellsPerLine,
NROFCELLSPERLINE and nrofcellsperline are all equivalent.
Required and optional parameter and syntax are documented for
each of the ER Mapper file types in the relevant chapters in this
manual.
Values. There are a number of different types of values used by
ER Mapper. These are listed below.
•
text strings: These are enclosed in double quotes and are case
sensitive (upper and lower case are not equivalent). Often strings
are used to display information in a message window or
description field while running ER Mapper. For example:
Name = "wetlands_scene"
Embedded quotes should be preceded by a backslash (\). For
example,
Description = "A \"sample\" name"
•
integers: These are whole numbers such as -3, 0, 2. For
example:
NumberOfBands = 5
•
real numbers: Floating point or real numbers may or may not
have a decimal point, for example 43 or 1.2353234 are both
valid. Exponent form, for example 1.313E+02 is also allowed. For
example:
NullCellValue = -999
NullCellValue = 123.456
NullCellValue = 1.0E+26
•
arrays: These can be arrays of integers or real numbers. They are
entered within curly braces:
parameter = {
. . . list of entries. . .
}
For example:
SubRegion = {
0 0
0 1851
15361851
15360
}
File Syntax
11
•
dates: Times are specified in GMT (Greenwich Mean Time) with
the following syntax:
Day Month DayOfMonth Hrs:Mins:Secs GMT Yr
For example:
SenseDate = Sun Dec 7 03:20:25 GMT 1989
•
angles: Angles are specified in Degrees:Minutes:Seconds
with Degrees and Minutes in integers and Seconds in decimal
seconds. For example,
Rotation = 23:45:34.6
•
keywords: A keyword entry requires you to select one of a
number of defined options. These options are described in the
relevant chapters in the remainder of this manual. Keywords are
used without quotation marks and are case insensitive (upper
and lower case is disregarded). For example, the available
options for the CellType above are:
•
Unsigned8BitInteger
•
Signed8BitInteger
•
Unsigned16BitInteger
•
Signed16BitInteger
•
Unsigned32BitInteger
•
Signed32BitInteger
•
IEEE4ByteReal
•
IEEE8ByteReal
and an example entry is:
CellType = Unsigned8BitInteger
12
File Syntax
Begin-End Blocks
The parameter specification entries are grouped into blocks of
related definitions. Each block is enclosed by a “block_name Begin”
statement and a “block_name End” statement. For example, the
major block which describes the contents of a dataset header file is
called the DatasetHeader block and all the entries are typed between
the two lines below.
DatasetHeader Begin
.
. body of block
.
DatasetHeader End
The entries within a block are indented to make it easier to see the
block structure. ER Mapper indents the entries when it creates or
modifies a file; however the indentation is optional. If you modify a
file and do not use indentation ER Mapper will still read and process
the file.
Blocks can contain one or more sub-blocks with more specific
information about an aspect of the larger block. For example, the
DatasetHeader block contains the sub-block RasterInfo which
describes the cell (pixel) size and image size (in cells). RasterInfo, in
turn, contains multiple entries of the sub-block BandId which
describe the bands or sensor channels contained in the file.
The order of the parameter specification entries within blocks and
sub-blocks and the order of sub-blocks within a block is arbitrary.
An example file
File Syntax
An example of a simplified raster header file is shown below.
13
# My simplified header file (this comment line will be ignored by ER Mapper)
# Note: This is for illustration only.
# All characters on a line after the ‘#’ are ignored (comments)
#
DataSetHeader Begin
# start of block
LastUpdated = Tue Sep 3 03:20:25 GMT 1998# a time entry
SensorName = "2-band multispectral"
# a string
SenseDate = Sun Nov 30 09:15:25 GMT 1989# a time entry
DataSetType = ERStorage # A keyword entry (see above)
DataType = Raster
# A keyword entry
ByteOrder = MSBFirst # A keyword entry
CoordinateSpace Begin # Sub block of the DataSetHeader
Datum = "RAW"
# String
Projection = "RAW" # String
CoordinateSystem = Raw # A keyword entry
Rotation = 12:23:34.2# An angle entry
CoordinateSpace End # Closes or ends this block
RasterInfo Begin
# Sub block of the DataSetHeader
CellType = Unsigned8BitInteger # A keyword entry
CellInfo Begin
# Sub block of the RasterInfo
XDimension = 10.0 # Real or floating
YDimension = 10.0 # point entries
CellInfo End
# Closes or ends this block
NrOfLines = 956
# Integer number (of lines)
NrOfCellsPerLine = 758 # Integer number (cells per line)
NrOfBands = 2
# Integer number (of bands)
BandId Begin
# Sub block of RasterInfo
Value = “0.123” # String (band pass in um)
Width = 0.42
# A real number (band width)
Units = “um”
# Units applicable to values
BandId End
# End of first band descriptor
BandId Begin
# Start of another BandId
# (Have two bands in data file)
Value = “0.234” # String (width of second band)
Width = 0.21
# Second band width
Units = “um”
# String describing units
BandId End
# Close the second block
RasterInfo End
# End of RasterInfo block
DataSetHeader End
# End of DataSet definition
14
File Syntax
Integrating data with ER Mapper
Introduction
One of the important considerations of any image processing system
is the range of image data formats it can access. ER Mapper can
read, import and display raster and vector files in a range of popular
formats. With its Dynamic Links capability, data from potentially any
source can be displayed and integrated into ER Mapper imagery.
ER Mapper Raster File
format
Raster images contain data for entire areas in regular grids. In
addition to those in ER Mapper Raster file (.ers) format, ER Mapper
can process and display raster images in the following formats.
•
ER Mapper Compressed Image (.ecw)
•
Windows Bitmap (.bmp)
•
ESRI BIL and GeoSPOT (.hdr)
•
GeoTIFF/TIFF (.tif)
•
JPEG (.jpg)
•
USGS DOQQ (Grayscale)
•
RESTEC/NASDA CEOS (.dat)
It is advisable to periodically check the ER Mapper Web site at
http:\\www.ermapper.com for new directly supported raster
file formats that have been added by ER Mapper or a third party.
Other raster formats must first be imported. During import a new file
in ER Mapper raster format is created. To return imported files to
their original format they must be exported.
External Data Source
Data Accessing
Mechanism
Editable
External Raster File Format
Import Raster
YES (header)
It is possible to add direct support for additional file formats by
writing a new ER Mapper raster translator. Contact Earth
Resource Mapping for more information if you want to know
more about writing raster translators.
Integrating data with ER Mapper
15
ER Mapper Vector File
format
Dynamic Links
Vector images contain information on an object by object basis.
Vector files can only be edited if they are in ER Mapper Vector or
ARC/INFO coverage format. Images in other vector formats must
first be imported into ER Mapper format. During import, a new file,
which can be fully edited and manipulated, is created. To return
imported files to their original format they must be exported.
External Data Source
Data Accessing
Mechanism
Editable
External Vector Files
Import Vector
YES
In addition, there are many other types of data that you might want
to incorporate into your display. ER Mapper’s open-ended Dynamic
Links provide a gateway through which you can integrate data from
virtually any system into your ER Mapper imagery.
The most powerful application of Dynamic Links is to access
information in other systems, such as GIS systems, databases and
spreadsheets. A simpler Dynamic Link might extract data from a flat
file.
Displaying data using Dynamic Links is totally different from
importing it. With Dynamic Links the data is not copied into
ER Mapper during linking but rather ER Mapper reaches out and uses
data which remains in its original system, in its original format.
Because ER Mapper works from source data rather than from copies,
the image automatically reflects any changes in the source
information each time the image is redisplayed.
External Data Source
Data Accessing
Mechanism
GIS systems
Dynamic Links
Database, spreadsheet data
Editable
Optional (depends on
dynamic link.)
System data
Generated data
External vector files
16
Integrating data with ER Mapper
SPREAD SHEET
e.g. Lotus 123
GIS SYSTEM
e.g. ARC/INFO
DBMS
e.g. Oracle
Informix
Ingres
Dynamic Link
EXTERNAL
VECTOR
FILES
e.g. DXF
GeoImage
PostScript
Dynamic Link
Dynamic Link
Dynamic Link
OTHER LINKS
e.g. Titles
Grids
Dynamic Link
Read/Import
VECTOR
IMAGES
ER Mapper
overlays
Read/Import
RASTER
IMAGES
Displaying data with ER Mapper
Integrating data with ER Mapper
17
Vector images and
Dynamic Links
Because of the overlap between Dynamic Link and vector
capabilities, vector files can be either imported or displayed using a
Dynamic Link. The results of the two processes are different. If you
want to be able to edit the image using ER Mapper you must import
the file into ER Mapper’s vector file format. If you don’t need to edit
the data, display it using a Dynamic Link.
External Data Source
Data Accessing
Mechanism
Editable
External Vector Files
Dynamic Links
NO
External Vector Files
Import Vector
YES
Open Standards
The Dynamic Links, Raster File formats and Vector File formats have
been designed to provide a standard interface for building links with
other systems. They are open to use by anyone wishing to design a
link to ER Mapper: perhaps individuals who want to incorporate data
from other systems into their images, or software suppliers who may
want to offer their clients a link to ER Mapper or data in ER Mapper
format.
Testing
This section contains all the information required to create a new
Dynamic Link or import or export program.
Programming support
To create a new Dynamic Link you will need to know about the
following:
•
the C programming language
•
PostScript
•
the system or data to be linked to
•
ER Mapper Dynamic Link mechanism.
To create a new import or export utility you will need to know about:
•
the C programming language
•
the data format you want to import or export
•
ER Mapper Raster or Vector dataset formats.
If you have difficulty in any of these areas please contact Earth
Resource Mapping for assistance.
Looking ahead
The remainder of this section is divided into the following chapters:
Raster File Format. This chapter describes the ER Mapper raster
dataset file format, consisting of an ASCII “.ers” header file and a
binary data file.
18
Integrating data with ER Mapper
Vector File Format. This chapter describes the ER Mapper vector
dataset file format, consisting of an ASCII “.erv” header file and an
ASCII data file.
Dynamic Links. This chapter starts by introducing the Dynamic Link
facility, using examples to indicate the range of its application. Next,
it looks at how Dynamic Links appear to an ER Mapper user and
details the programs that are needed to construct a new link. The
chapter ends with the complete code for three examples of Dynamic
Link.
PostScript. This chapter examines how ER Mapper PostScript
interpretation differs from standard interpretation.
Supplied Dynamic
SUPPLIED DYNAMIC LINKS (note that this list is subject to change)
ARC/INFO Dynamic Link
ARC/INFO coverage
Contours
External Vector formats
AutoCAD DXF
GeoImage
MicroStation DGN File
Table of data shown as Circles
Table circles with Rotation
Table of data shown as Outline Circles
Grid Datasource Points
Grid Datasource TIN
Regions
Regions Outlined
Regions Filled
Integrating data with ER Mapper
19
SUPPLIED DYNAMIC LINKS (note that this list is subject to change)
PostScript
8.5x11 inch Monocolor PostScript
8.5x11 inch Monocolor Compressed PostScript
8.5x11 inch Truecolor PostScript
8.5x11 inch Truecolor Compressed PostScript
Example User Dynamic
Links
Example User Dynamic Link
Show arguments for No Parameter
Show arguments for Dataset Chooser
Show arguments for Fixed Parameter
Show arguments for $$ALG Parameter
Show arguments for Link Chooser
Show arguments for External Link Chooser
Show arguments for Script Link Chooser
Dynamic Link coded PostScript
Example Dynamic Links
Links to DBMS
Example: Dynamic Link to Oracle (UNIX only)
In this case the data being extracted from the system is tables of
figures rather than vector data. The figures are processed and
displayed as circles.
Links to Vector Files
Example: External Vector Formats / AutoCAD DXF
This overlay links to any flat vector file with a “.dxf” extension. This
link can be used to access GIS data when a GIS system is not
available.
Other links of this type are Dynamic Links to GeoImage and
PostScript files. Each link is set up to accept data in the particular
external file format.
20
Integrating data with ER Mapper
Raster Datasets and Header Files (.ers)
Introduction
The header file
An ER Mapper raster dataset is made up of two files:
•
the dataset header file, and
•
the data file.
The dataset header file is an ASCII file describing the raster data in
the data file. The dataset header file normally has the same name as
the data file that it is describing, with the file extension “.ers” added.
For example, “Australia_DTM.ers” is a valid raster dataset header
file name for the raster Data file named “Australia_DTM”. The
header file may point to a data file that has a different name via the
DataFile field in the header file.
ER Mapper automatically creates a header file for another image
format like TIFF to store ancillary information for defining
regions etc.
The data file
The data file contains the data itself. The raster data is stored in a
binary Band-Interleaved-by-Line (BIL) format with a pixel data type
defined in the accompanying header file. This format is explained in
detail later.
The data file name has no extension. For example,
“Australia_DTM” is the raster data file described by the
“Australia_DTM.ers” header file.
This chapter details the formats for these two files.
The raster header
file
The entire header file holds information about the data source and is
contained in the DatasetHeader Block. There are two compulsory
sub-blocks, the CoordinateSpace Block and the RasterInfo Block.
•
The CoordinateSpace Block defines the image coordinate space
and location.
•
The RasterInfo Block defines the characteristics of the data in the
accompanying data file and may contain a number of optional
sub-blocks.
The next section describes the entries in the DatasetHeader block
and the subsequent sections describe sub-blocks.
DatasetHeader
Block
This block contains the whole of the Header file. It has two
compulsory sub-blocks: the CoordinateSpace block and the
RasterInfo block.
Raster Datasets and Header Files (.ers)
21
A simple raster header file illustrating the compulsory entries is
shown below.
DatasetHeader Begin
Version = “7.2”
Name = “Australia.ers”
DataFile = “Shared_Data/Australia”
DataSetType = ERStorage
DataType = Raster
ByteOrder = MSBFirst
CoordinateSpace Begin
Datum = “RAW”
Projection = “RAW”
CoordinateType = RAW
Rotation = 0:0:0.0
CoordinateSpace End
RasterInfo Begin
CellType = IEEE4ByteReal
NrOfLines = 401#Number of lines
NrOfCellsPerLine = 300#Number of cells/line
NrOfBands = 3 #Number of bands
RasterInfo End
DatasetHeader End
Some more complex examples of header files can be found in
the “Example dataset header files” section towards the end
of this chapter.
The entries of a raster dataset header are described below:
Compulsory entries
•
Version: Used to define the version. For example,
Version = "6.0"
•
DataSetType: The type of image to be displayed. Allowed values
are: ‘ERStorage’ - ER Mapper dataset format
‘Translated’ - external (non ER Mapper) format.
DataSetType = ERStorage
There are many import utilities that may be used to convert
images from an external file format into ER Storage format. See
“Vector datasets and header files (.erv)”.
•
DataType: DataType tells ER Mapper what type of image it is.
Values allowed are Raster or Vector. For example,
DataType = Raster
22
Raster Datasets and Header Files (.ers)
Vector image entries are detailed in the “Vector datasets and
header files (.erv)” chapter.
•
ByteOrder: Indicates the byte ordering of the data. Can be
either:
•
MSBFirst - Most significant byte first.
•
LSBFirst - Least significant byte first.
For example,
ByteOrder = MSBFirst
Optional entries
•
CoordinateSpace block: Defines the image projection. See
“Coordinate space block” below.
•
RasterInfo block: Defines the image format. See “Raster info
•
Name: The name of this header file. ER Mapper inserts or
updates this entry whenever it edits the header file. This includes
changes made via the Dataset Header Editor, adding regions,
calculating statistics, analyzing the image before balancing etc.
•
SourceDataset: When processing classified datasets, the training
region statistics must be calculated from the dataset on which
the training regions were originally defined. This is done by using
the SourceDataset entry which contains the path/name of the
dataset on which the training regions were originally defined,
e.g., c:\imagefiles\someimage.tif.
•
DataFile: The name of the data file described by this header file.
The defaults to the same name (without the .ers extension) and
need only be specified if the data file has a different name. Some
applications like CDROMS will always enforce the dot if there is
no extension. You can have a header called frog.ers which
contains the line Datafile = “frog.”, and it will access the file
correctly.
•
LastUpdated: The date the file was last updated. For example,
block” below.
LastUpdated = Mon Dec 2 03:14:55 GMT 1991
•
SensorName: The location and name of the Camera File which
has details of the sensor used to take the image. For example,
SensorName = ”C:\Program Files\ERDAS\ERDAS ER Mapper
7.2\examples\Tutorial\camera2.cam"
•
SenseDate: The date the data was collected. For example,
SenseDate = Mon Feb 5 06:39:03 GMT 1990
Raster Datasets and Header Files (.ers)
23
•
HeaderOffset: Specifies in bytes the length of any header data in
the data file, for non ER Mapper format BIL files. This means that,
if a file is BIL format, with a fixed length header, specifying
HeaderOffset=512
in the ER Mapper header file will skip 512 bytes at the beginning
of the data file. In this way, an ER Mapper header file can allow
for any BIL format file with a fixed length header.
•
Coordinate Space
Block
FFTInfo block: In a transformed image, stores the original image
information to be used to reconstruct the original image after a
reverse transformation. See “FFTInfo block” below.
The “CoordinateSpace” block specifies the datum and projection
type, the type of coordinates used, the units and rotation from true
North. For example,
CoordinateSpace Begin
Datum = “RAW”
Projection = “RAW”
CoordinateType = RAW
Units = “METERS”
Rotation = 0:0:0.0
CoordinateSpace End
The Units entry does not apply to the cell-sizes shown in
theCellInfo block.
Compulsory entries
•
Datum: The datum for the map projection. Allowable values are
RAW or one of the datums supported by ER Mapper (specified in
quotes). For example,
Datum = "RAW" or Datum = "AGD66"
•
Projection: The map projection for the image. Allowable values
are RAW or one of the map projections supported by ER Mapper
(specified in quotes). For example,
Projection = "RAW"
or
Projection = "TMAMG53"
•
CoordinateType: Defines how coordinates are expressed. Note
that quotes are not used in this entry. Allowed types are:
•
24
RAW —Coordinates expressed as meters in master
coordinates.
Raster Datasets and Header Files (.ers)
•
EN —Coordinates expressed as Easting Northing coordinate
pair
•
LL —Coordinates expressed as latitude and longitude in
degrees.
For example,
CoordinateType = RAW
Optional entries
•
Units: The unit of length used in the image (and the
RegistrationCoord block).
Allowed entries are:
•
"natural"
•
"METERS"
•
"U.S. SURVEY FOOT"
•
"IMPERIAL YARD"
•
other units defined in the control file
‘ERMAPPER\GDT_DATA\lenunits.dat’
The most common units are "METERS" and "natural". If the
units are not specified, they default to "METERS" for RAW images
and "natural" for non-RAW images. Here, "natural" means the
natural units for the projection. For example,
Units = "METERS"
•
Rotation: Rotation defines the rotation of the image from true
North in degrees counter-clockwise. For example,
Rotation = 0:0:0.0
defines no rotation from true North.
Raster Datasets and Header Files (.ers)
25
RasterInfo Block
The RasterInfo block is a compulsory sub-block of the DatasetHeader
block. It contains information about the image lines, bands and cells.
The example below has both compulsory and optional entries.
RasterInfo Begin
CellType = IEEE4ByteReal
NullCellValue = -9999
CellInfo Begin
Xdimension = 50.0
Ydimension = 50.0
CellInfo End
NrOfLines = 401
NrOfCellsPerLine = 300
RegistrationCoord Begin
Eastings = 780810.6
Northings = 7982367.8
RegistrationCoord End
RegistrationCellX = 0.0
RegistrationCellY = 401.0
NrOfBands = 1
BandId Begin
Value = “0.645”
Width = 0.071
Units = “um”
BandId End
RasterInfo End
Compulsory entries
•
CellType: The type of data in the image. Allowed keywords are:
•
Unsigned8BitInteger
•
Signed8BitInteger
•
Unsigned16BitInteger
•
Signed16BitInteger
•
Signed32BitInteger
•
Unsigned32BitInteger
•
IEEE4ByteReal
•
IEEE8ByteReal
For example,
CellType = IEEE4ByteReal
•
NrOfLines: Integer number of lines in the image. For example,
NrOfLines = 401
26
Raster Datasets and Header Files (.ers)
•
NrOfCellsPerLine: Integer number of cells for each line in the
image. For example,
NrOfCellsPerLine = 300
•
NrOfBands: Integer number of bands in the image. For example,
NrOfBands = 3
Optional entries
•
NullCellValue: Indicates the value for “null cells”. This is an
optional indicator which may have any integer or real value. For
example,
NullCellValue= -9999
This example specifies that any cell with the value “-9999” should
be considered null data.
•
RegistrationCellX and RegistrationCellY : The image X and Y
coordinates of the cell which corresponds to the Registration
Coordinate. Note that the RegistrationCellX and
RegistrationCellY can be fractional values. If
RegistrationCellX and RegistrationCellY are not specified,
they are assumed to be (0,0), which is the top left corner of the
image. For example
RegistrationCellX = 0.0
RegistrationCellY = 401.0
•
CellInfo Block: The X and Y dimensions of a data cell. See
•
RegistrationCoord Block: The location of the point in the image
•
BandID Block: A description of what the bands in the image
represent in physical terms. See “RegistrationCoord block”
below.
•
SensorInfo Block: Calibration details of the sensor (e.g. camera)
used to take the image. Includes information on the location of
Fiducial Points, lens focal length and location of the Principal
Point. It is required for orthorectification. See “SensorInfo
block” below.
•
WarpControl Block: Stores information about rectification
“CellInfo block” below.
specified by the RegistrationCellX and RegistrationCellY
parameters. This block is required for non-RAW images. See
“RegistrationCoord block” below.
including the ground control points. See “WarpControl block”
below.
•
RegionInfo Block: Defines regions in the image and lists
statistics for them. See “RegionInfo block” below.
Raster Datasets and Header Files (.ers)
27
CellInfo Block
This optional block is a sub-block of the RasterInfo Block. It specifies
the X and Y dimensions of an image cell.
CellInfo Begin
Xdimension = 50.0
Ydimension = 50.0
CellInfo End
•
Xdimension: X dimension of each image cell in meters. Default is
1.
Xdimension = 50.0
•
Ydimension: Y dimension of each image cell in meters. Default is
1.
Ydimension = 50.0
Registration
Coord Block
The “RegistrationCoord” block is a sub-block of the RasterInfo block.
It defines the location of the registration cell in the image specified
by the RegistrationCellX and RegistrationCellY parameters. The
coordinates must be compatible with the system specified in the
CoordinateType parameter. Eastings/Northings or MetersX/MetersY
or Latitude/Longitude are specified. The block is required for nonRAW images. For example:
RegistrationCoord Begin
Eastings= 780810.6
Northings= 7982367.8
RegistrationCoord End
Eastings = 780810.6
Northings = 7982367.8
or
MetersX = 8625.0
MetersY = 9225.0
or
Latitude = 34:16:54.98
Longitude = 140:34:3.2
28
Raster Datasets and Header Files (.ers)
BandId Block
The optional “BandId” block is a sub-block of the RasterInfo block. It
specifies what each of the bands in the image represents in physical
terms. The “Width” value is optional and specifies the spectral width
of the image band in the units defined by the Units parameter. For
example,
BandId Begin
Value = "0.645"
Width = 0.071
Units = "um"
BandId End
Compulsory entries
•
Value: Value description to appear in the band button in the
Algorithm window
Value = "0.645"
•
Units: Units for band description
Units = "um"
Optional entries
•
Width: Spectral width of the image band, in the units defined
below, used for closest spectral matching with bands from other
images
Width = 0.071
SensorInfo Block
The optional “SensorInfo” block is a sub-block of the RasterInfo
block. It provides details of the sensor (e.g. camera) used to take the
image.
This information is used to orthorectify the image.
For example,:
SensorInfo Begin
CameraManufacturer= "Wild"
CameraModel = "RC20"
LensSerialNr = "13115"
CalibrationDate = Wed Oct 23 00:00:00 GMT 1996
SensorType = MetricCamera
PlatformType = Aerial
FiducialInfo Begin
PrinciplePointOffsetX = 0
PrinciplePointOffsetY = 0
FiducialPointTopLeft Begin
IsOn = Yes
IsLocked = No
CellX = 210.4633887599771
CellY = 320.1004736175112
OffsetX = -105.987
OffsetY = 106.007
Raster Datasets and Header Files (.ers)
29
FiducialPointTopLeft End
FiducialPointTopRight Begin
IsOn = Yes
IsLocked = No
CellX = 5220.712372586905
CellY = 321.5464165158579
OffsetX = 106.008
OffsetY = 106.016
FiducialPointTopRight End
FiducialPointBottomLeft Begin
IsOn = Yes
IsLocked = No
CellX = 202.7989504537253
CellY = 5332.408872554061
OffsetX = -105.986
OffsetY = -105.99
FiducialPointBottomLeft End
FiducialPointBottomRight Begin
IsOn = Yes
IsLocked = No
CellX = 5213.025106596184
CellY = 5331.571326150155
OffsetX = 106.01
OffsetY = -105.99
FiducialPointBottomRight End
FiducialInfo End
FocalLength = 152.793
PrinciplePointX = 1
PrinciplePointY = 1
SensorInfo End
Compulsory entries
•
SensorType: The type of sensor used. Value can be
MetricCamera, nonMetricCamera or LineArray.
SensorType = MetricCamera
•
PlatformType: The type of platform on which the sensor was
mounted. Value can be Aerial, Terrestrial or Satellite.
PlatformType = Aerial
•
Optional entries
•
FiducialInfo Block: Contains information on the number and
location of Fiducial Points.
CameraManufacturer: The name of the camera manufacturer,
for example:
CameraManufacturer = "Leica"
•
30
CameraModel: The model of camera used, for example:
Raster Datasets and Header Files (.ers)
CameraModel = "RC20"
•
LensSerialNr: The serial number of the lens, for example:
LensSerialNr = "100100"
•
CalibrationDate: The date of the camera calibration report from
which this information is obtained.
CalibrationDate = Mon Jun 01 00:00:00 GMT 1998
FiducialInfo Block
The “FiducialInfo” block is a sub-block of the SensorInfo block. It
provides details of the Fiducial Points inserted by the camera.
•
PrincipalPointOffsetX,Y: The amount, in millimeters, that the
Principal Point is offset from the lens center due to lens
distortion.
PrinciplePointOffsetX = 0.006
PrinciplePointOffsetY = 0
Fiducial point block
Each Fiducial Point has one of these blocks, which defines its position
and status. For example:
FiducialPointMiddleTop Begin
IsOn = Yes
IsLocked = No
CellX = 2716.929167534793
CellY = 227.1583440160684
OffsetX = 0.011
OffsetY = 110.007
FiducialPointMiddleTop End
•
IsOn: Flag indicating whether the Fiducial Point is used in
calculating RMS errors.
•
Islocked: Flag indicating whether the Fiducial Point position is
locked for further adjusting.
•
CellX, CellY: Cell position of the Fiducial Point in the image.
•
RegionInfo Block
OffsetX, OffsetY: Fiducial point position relative to the Principal
Point.
The optional ‘RegionInfo’ block is a sub-block of the RasterInfo block.
It defines regions in the image and lists statistics for those regions.
Where a number of regions have been defined for a multi-band
image this block may be of a considerable size. For import and export
purposes this block can be ignored.
•
Type: Must be “Polygon”. Other types may be generated by
ER Mapper but may be ignored.
Raster Datasets and Header Files (.ers)
31
Value = "0.645"
•
RegionName: Name for the region to be used on menus.
Width = 0.071
•
SubRegion: Coordinates of points on the region outline, in image
cell coordinates.
SubRegion = {
33.6551 55.6845
219.3385 68.4455
}
•
WarpControl
Block
Stats Block: Ignore this block. Generated by ER Mapper.
The optional ‘WarpControl’ block is a sub-block of the RasterInfo
block. It defines the parameters to be used for the image to be
rectified. This information does not pertain to the image referenced
by this header file, but to the resultant rectifed image.
An example WarpControl Block is as follows:
WarpControl Begin
WarpType = Ortho
WarpSampling = Nearest
Rotation = 0
DemFile = "San_Diego_DEM.ers"
DemBandNr = 1
ChooseGcpsFromDigitizer = No
ChooseGcpsFromImage = Yes
GcpsChosenFrom = “San_Diego_rectified.alg”
OutputFile = "San_Diego_Airphoto_34_rectified.ers"
UseAverageHeight = No
AverageHeight = 0
OutputCellSizeX = 0.8784871184780805
OutputCellSizeY = 0.8784871184780805
OutputHasNullCells = Yes
OutputNullCellValue = 0
Correction Begin
RadialLens = No
PolyLens = No
Atmospheric = No
EarthCurvature = No
Correction End
GivenOrthoInfo Begin
AttitudeOmega = 0
AttitudePhi = 0
AttitudeKappa = 0
ExposureCenterX = 0
ExposureCenterY = 0
32
Raster Datasets and Header Files (.ers)
ExposureCenterZ = 0
SCALE = 0
CoordinateSpace Begin
Datum = "RAW"
Projection = "RAW"
CoordinateType = RAW
Rotation = 0:0:0.0
CoordinateSpace End
GivenOrthoInfo End
CoordinateSpace Begin
Datum = "NAD27"
Projection = "NUTM11"
CoordinateType = EN
Units = "METERS"
Rotation = 0:0:0.0
CoordinateSpace End
Extents Begin
TopLeftCorner Begin
Eastings = 481254.9675890448
Northings = 3623804.501505829
TopLeftCorner End
BottomRightCorner Begin
Eastings = 485756.9891375387
Northings = 3619284.200966488
BottomRightCorner End
Extents End
ControlPoints = {
"1035" Yes No 2344.650885 3546.419458
3620906.21 3.105
"165" Yes No 753.008933 3870.075769
3620609.47 3.956
"1033" No No 1135.630546 3300.182792
3621108.2 3.781
"166" Yes No 1899.884085 1809.975198
3622446.77 9.336
"1048" Yes No 4543.843305 2126.060086
3622136.67 89.52
"1047" Yes No 4023.228765 3093.897173
3621312.38 69.78
"1049" Yes No 4285.065234 1075.63221
3623042.13 90.60
"1050" No No 4421.36311 195.759133
3623816.47 90.47
"1043" Yes No 3328.0604
456.3793
3623601.21 81.31
"1040" Yes No 2446.265469 586.068957
3623498.02 83.91
"1036" Yes No 628.09969
1281.942016
3622934.34 4.019
}
Raster Datasets and Header Files (.ers)
483270.73
481853.04
482174.61
482865.1
485146.6
484710.74
484932.5
485056.3
484120.33
483353.38
481698.47
33
WarpControl End
•
WarpType: Specifies the type of geocoding to be done on the
image. Allowable values are:
•
Ortho
•
OrthoAdvanced
•
Polynomial
•
Triangulation
•
Rotation: Specifies the amount by which the image is to be
rotated anti-clockwise in decimal degrees. 0 indicates no
rotation.
•
ChooseGcpsFromDigitizer: Specifies whether a digitizer was used
•
ChooseGcpsFromImage: Specifies whether a geocoded
•
UseAverageHeight: Specifies whether an average height is to
•
AverageHeight: Specifies the average height to be used if the
•
Correction Block: Specifies the type of correction to done when
the image is geocoded.
•
GivenOrthoInfo Block: Contains the parameters to be used for
•
CoordinateSpace Block: Specifies the new coordinate type and
•
ControlPoints: Specifies the location and properties of Ground
to select Ground Control Points (GCPs) used for geocoding the
image. Value can be either ‘Yes’ or ‘No’.
(corrected) image was used to select Ground Control Points
(GCPs) to be used for rectifying the image. Value can be either
‘Yes’ or ‘No’.
used instead of a DEM for orthorectifying the image. Value can
be either ‘Yes’ or ‘No’.
UseAverageHeight was set to ‘Yes’.
orthorectifying the image. This is only applicable if WarpType is
set to “OrthoAdvanced”.
rotation of the image.
Control Points (GCPs).
The parameters in the ControlPoint entries are:
1. Name: The name of the point. For example, "Name"
2. On: Whether the point is taken into account when calculating the
rectification coefficients.
34
Raster Datasets and Header Files (.ers)
3. Editable: Whether the point can be edited or not. Allowable values
are Yes or No.
4. FROM cellx: The x coordinate of the point in the FROM coordinate
system.
5. FROM celly: The y coordinate of the point in the FROM coordinate
system.
6. TO x: The x coordinate of the point in the TO coordinate system.
7. TO y: The y coordinate of the point in the TO coordinate system.
8. TO z: The z coordinate of the point in the TO coordinate system. This
is only required if WarpType is set to “Ortho”.
Correction Block
The Correction Block is a sub-block of the WarpControl block. It
indicates the types of correction to be carried out on the image
during geocoding This is currently not used by ER Mapper.
Correction Begin
RadialLens = No
PolyLens = No
Atmospheric = No
EarthCurvature = No
Correction End
•
RadialLens: Radial lens distortion is introduced by irregularities
•
PolyLens: Poly lens distortion.
•
Atmospheric: Atmospheric distortion is caused by changes in the
•
EarthCurvature: Distortion caused by the earth’s curvature.
in the camera (sensor) lens.
earth’s atmosphere.
Raster Datasets and Header Files (.ers)
35
GivenOrthoInfo
Block
The GivenOrthoInfo block is a sub-block of the WarpControl block. It
contains information on the exact position of the sensor platform
when the image was taken. This is known as exterior orientation and
is used to orthorectify the image.
GivenOrthoInfo Begin
AttitudeOmega = 0
AttitudePhi = 0
AttitudeKappa = 0
ExposureCenterX = 0
ExposureCenterY = 0
ExposureCenterZ = 0
SCALE = 0
CoordinateSpace Begin
CoordinateType = None
Rotation = 0:0:0.0
CoordinateSpace End
GivenOrthoInfo End
36
•
AttitudeOmega: The pitch about the Y axis, in radians.
•
AttitudePhi: The roll about the X axis, in radians.
•
AttitudeKappa: The yaw about the Z axis, in radians.
•
ExposureCenterX: The position of the exposure center of the
camera in the X plane of the image. This is in the same units as
defined in the CoordinateSpace block.
•
ExposureCenterY: The position of the exposure center of the
camera in the Y plane of the image. This is in the same units as
defined in the CoordinateSpace block.
•
ExposureCenterZ: The height of the exposure center of the
camera. This is in the same units as defined in the
CoordinateSpace block.
•
SCALE: The scale of the image as a decimal value. This
parameter is calculated internally by ER Mapper.
Raster Datasets and Header Files (.ers)
FFTInfo Block
The optional ‘FFTInfo’ block is a sub-block of the DatasetHeader
block. When you carry out a Fourier transform the information about
the original image is stored here. This is used to reconstruct the
original image when reversing the transformation. For example,
FFTInfo Begin
ForwardTransform = FFT
SpectrumAmount = Full
SpatialDataset = "Shared_Data/FFT_Input_Image.ers"
PadCellX = 10
PadCellY = 10
CoordinateSpace Begin
Datum = "NAD27"
Projection = "NUTM11"
CoordinateType = EN
Rotation = 0:0:0.0
CoordinateSpace End
RasterInfo Begin
.... the RasterInfo block for the original image ....
RegionInfo End
RasterInfo End
FFTInfo End
Raster Datasets and Header Files (.ers)
37
Example dataset
header files
Example Landsat header
file
DatasetHeader Begin
Version = "3.0"
LastUpdated = Tue Nov 19 02:16:39 GMT 1991
SensorName = "Landsat_TM"
SenseDate = Fri May 18 07:08:46 GMT 1990
DataSetType = ERStorage
DataType = Raster
ByteOrder = MSBFirst
CoordinateSpace Begin
Datum = "RAW"
Projection = "RAW"
CoordinateType = RAW
Rotation = 0:0:0.0
CoordinateSpace End
RasterInfo Begin
CellType = Unsigned8BitInteger
NullCellValue = 0
CellInfo Begin
Xdimension = 30
Ydimension = 30
CellInfo End
NrOfLines = 1000
NrOfCellsPerLine = 1000
NrOfBands = 7
RasterInfo End
DatasetHeader End
38
Raster Datasets and Header Files (.ers)
Georeferenced dataset
header file
Here is a dataset header file for an image which is georeferenced to
AMG coordinates.
DatasetHeader Begin
DataSetType = ERStorage
HeaderOffset= 512
DataType = Raster
ByteOrder
= MSBFirst
CoordinateSpace Begin
Datum = “AGD66”
Projection = “TMAMG53”
CoordinateType = EN
Rotation = 0:0:0.0
CoordinateSpace End
RasterInfo Begin
CellType = IEEE4ByteReal
NullCellValue = -9999
CellInfo Begin
Xdimension = 50.0
Ydimension = 50.0
CellInfo End
NrOfLines = 401
NrOfCellsPerLine = 300
RegistrationCoord Begin
Eastings = 780810.6
Northings = 7982367.8
RegistrationCoord End
RegistrationCellX = 0.0
RegistrationCellY = 401.0
NrOfBands = 1
BandId Begin
Value = “0.645”
Width = 0.071
Units = “um”
BandId End
RasterInfo End
DatasetHeader End
Example of a complex
dataset header file
This example is a more complex header with many of the available
options. It includes orthorectification and region information which
has been added to the header by ER Mapper as it calculates
statistical information.
DatasetHeader Begin
Version = "5.7"
LastUpdated = Mon Aug 10 03:43:43 GMT 1998
SensorName n=
"C:\Program Files\ERDAS\ERDAS ER Mapper 7.2\
examples\Tutorial\camera2.cam"
DataSetType = ERStorage
Raster Datasets and Header Files (.ers)
39
DataType = Raster
ByteOrder = MSBFirst
CoordinateSpace Begin
Datum = "NAD27"
Projection = "NUTM11"
CoordinateType = EN
Rotation = 0:0:0.0
CoordinateSpace End
RasterInfo Begin
CellType = Unsigned8BitInteger
CellInfo Begin
Xdimension = 0.75
Ydimension = 0.75
CellInfo End
NrOfLines = 694
NrOfCellsPerLine = 652
RegistrationCoord Begin
Eastings = 484875.8624313
Northings = 3620515.084881
RegistrationCoord End
NrOfBands = 3
BandId Begin
Value = "Red"
BandId End
BandId Begin
Value = "Green"
BandId End
BandId Begin
Value = "Blue"
BandId End
SensorInfo Begin
CameraManufacturer = "Leica"
CameraModel = "RC20"
LensSerialNr = "100100"
CalibrationDate = Mon Jun 01 00:00:00 GMT 1970
SensorType = MetricCamera
PlatformType = Aerial
FiducialInfo Begin
PrinciplePointOffsetX = 0.006
PrinciplePointOffsetY = 0
FiducialPointTopLeft Begin
IsOn = Yes
IsLocked = No
CellX = 210.4633887599771
CellY = 320.1004736175112
OffsetX = -105.987
OffsetY = 106.007
FiducialPointTopLeft End
FiducialPointTopRight Begin
IsOn = Yes
40
Raster Datasets and Header Files (.ers)
IsLocked = No
CellX = 5220.712372586905
CellY = 321.5464165158579
OffsetX = 106.008
OffsetY = 106.016
FiducialPointTopRight End
FiducialPointBottomLeft Begin
IsOn = Yes
IsLocked = No
CellX = 202.7989504537253
CellY = 5332.408872554061
OffsetX = -105.986
OffsetY = -105.99
FiducialPointBottomLeft End
FiducialPointBottomRight Begin
IsOn = Yes
IsLocked = No
CellX = 5213.025106596184
CellY = 5331.571326150155
OffsetX = 106.01
OffsetY = -105.99
FiducialPointBottomRight End
FiducialPointMiddleLeft Begin
IsOn = Yes
IsLocked = No
CellX = 112.1652994450148
CellY = 2828.169317438489
OffsetX = -109.989
OffsetY = 0.012
FiducialPointMiddleLeft End
FiducialPointMiddleRight Begin
IsOn = Yes
IsLocked = No
CellX = 5310.975805982356
CellY = 2828.913786847189
OffsetX = 110.01
OffsetY = 0.013
FiducialPointMiddleRight End
FiducialPointMiddleTop Begin
IsOn = Yes
IsLocked = No
CellX = 2716.929167534793
CellY = 227.1583440160684
OffsetX = 0.011
OffsetY = 110.007
FiducialPointMiddleTop End
FiducialPointMiddleBottom Begin
IsOn = Yes
IsLocked = No
CellX = 2708.487218792691
Raster Datasets and Header Files (.ers)
41
CellY = 5428.231114609829
OffsetX = 0.005
OffsetY = -109.991
FiducialPointMiddleBottom End
FiducialInfo End
FocalLength = 152.793
PrinciplePointX = 1
PrinciplePointY = 1
SensorInfo End
WarpControl Begin
WarpType = Ortho
WarpSampling = Nearest
Rotation = 0
ChooseGcpsFromDigitizer = No
ChooseGcpsFromImage = Yes
GcpsChosenFrom =
"C:\Program Files\ERDAS\ERDAS ER Mapper
7.2\examples\Data_Types\Airphoto\RGB.alg"
UseAverageHeight = Yes
AverageHeight = 50
Correction Begin
RadialLens = No
PolyLens = No
Atmospheric = No
EarthCurvature = No
Correction End
GivenOrthoInfo Begin
AttitudeOmega = 0
AttitudePhi = 0
AttitudeKappa = 0
ExposureCenterX = 0
ExposureCenterY = 0
ExposureCenterZ = 0
SCALE = 0
CoordinateSpace Begin
CoordinateType = None
Rotation = 0:0:0.0
CoordinateSpace End
GivenOrthoInfo End
CoordinateSpace Begin
Datum = "NAD27"
Projection = "NUTM11"
CoordinateType = EN
Rotation = 0:0:0.0
CoordinateSpace End
ControlPoints = {
"1035" Yes No 2344.650885 3546.419458 483270.73
3620906.21 3.105
"165" Yes No 1135.630546 3300.182792 482174.61
3621108.2 3.781
42
Raster Datasets and Header Files (.ers)
"166" Yes No 1899.884085 1809.975198 482865.1
3622446.77 9.336
"1048" Yes No 4543.843305 2126.060086 485146.6
3622136.67 89.522
"1047" Yes No 4023.228765 3093.897173 484710.74
3621312.38 69.787
"1049" Yes No 4285.065234 1075.63221 484932.5
3623042.13 90.606
"1050" No No 4421.36311 195.759133 485056.3
3623816.47 90.474
}
WarpControl End
RegionInfo Begin
Type = Polygon
RegionName = "All"
RGBcolour Begin
Red = 0
Green = 63057
Blue = 56957
RGBcolour End
SubRegion= {
0 0
0 694
652 694
652 0
}
Stats Begin
SubsampleRate = 4
NumberOfBands = 3
NumberOfNonNullCells = {
28362 28362 28362
}
MinimumValue= {
0 0 0
}
MaximumValue= {
247 246 247
}
MeanValue= {
110.6474860729 106.2357379592
96.27251251675
}
MedianValue= {
105 94 90
}
CovarianceMatrix= {
8092.874707019 6894.430764364
5603.49383238
6894.430764364 6346.305766934
5192.448925684
Raster Datasets and Header Files (.ers)
43
5603.49383238
4400.993009794
}
Stats End
RegionInfo End
RasterInfo End
DatasetHeader End
Raster data file
44
5192.448925684
An ER Mapper raster data file contains binary data in BandInterleaved-by Line (BIL) format. The type and amount of data is
specified in the header file. The figure below illustrates the ordering
of data in an ER Mapper raster data file.
Raster Datasets and Header Files (.ers)
Raster Datasets and Header Files (.ers)
45
46
Raster Datasets and Header Files (.ers)
Vector Datasets and Header Files (.erv)
Introduction
An ER Mapper Vector dataset is made up of two files:
•
the dataset header file, and
•
the data file.
The header file
The dataset header file is an ASCII file describing the vector data in
the data file. The dataset header file generally has the same name
as the data file that it is describing, with the file extension “.erv”
added. For example, “Loxton_contour.erv” is the dataset header
file name corresponding to the vector data file “Loxton_contour”.
The header file may point to a data file that has a different name via
the DataFile field in the header file.
The data file
The vector data file contains the data itself, also in ASCII format. The
data file name has no extension. For example, “Loxton_contour” is
the vector data file described by the “Loxton_contour.erv” Header
file.
This chapter details the formats for these two files.
Vector Datasets and Header Files (.erv)
47
Vector header file
format
The vector file format is similar to the raster header file format,
except that the VectorInfo block takes the place of the RasterInfo
block. An example vector header file is listed below, followed by a
description of the VectorInfo block entries.
DatasetHeader Begin
Version = “5.0”
DataFile = “Shared_Data/Australia”
LastUpdated = Fri Nov 15 02:49:12 GMT 1991
SenseDate = Tue Sep 4 04:56:37 GMT 1990
DataSetType = ERStorage
DataType = Vector
ByteOrder = MSBFirst
CoordinateSpace Begin
Datum = “AGD66”
Projection = “TMAMG54”
CoordinateType = EN
Rotation = 0:0:0.0
CoordinateSpace End
VectorInfo Begin
Type = ERVEC
FileFormat = ASCII
Extents Begin
TopLeftCorner Begin
Eastings = 453982
Northings = 6210075
TopLeftCorner End
BottomRightCorner Begin
Eastings = 477048
Northings = 6182287
BottomRightCorner End
Extents End
VectorInfo End
DatasetHeader End
The entire header file is contained in the DatasetHeader Block. This
holds information about the data source and has two sub-blocks, the
CoordinateSpace Block and the VectorInfo Block.
•
The CoordinateSpace Block defines the dataset map projection.
•
The VectorInfo Block defines the characteristics of the data in the
accompanying data file and the file extents.
The next section describes the entries in the DatasetHeader block
and the subsequent sections describe sub-blocks.
48
Vector Datasets and Header Files (.erv)
DatasetHeader
Block
This block contains the whole of the Header file. It has two
compulsory sub-blocks: the CoordinateSpace block and the
VectorInfo block. The DatasetHeader entries and the
CoordinateSpace block entries are the same as for raster dataset
headers. They are repeated here for completeness.
A simple vector header file is is shown below.
DatasetHeader Begin
Version
= "5.5"
DataFile = “Shared_Data/Australia”
LastUpdated
= Mon Dec 2 03:14:55 GMT 1994
DataSetType
= ERStorage
DataType
= Vector
ByteOrder
= MSBFirst
CoordinateSpace Begin
Datum
= "RAW"
Projection
= "RAW"
CoordinateType = RAW
CoordinateSpace End
VectorInfo Begin
Type
= ERVEC
FileFormat
= ASCII
Extents Begin
TopLeftCorner Begin
MetersX
= 0
MetersY
= 0
TopLeftCorner End
BottomRightCorner Begin
MetersX
= 1000
MetersY
= 1000
BottomRightCorner End
Extents End
VectorInfo End
DatasetHeader End
The entries of a vector dataset header are described below:
Compulsory entries
•
Version: Used to define the version. For example,
Version = "5.5"
•
DataSetType: The type of dataset to be displayed. Currently the
only allowed value is ERStorage.
DataSetType = ERStorage
There are many import utilities that may be used to convert
datasets from a foreign file format into ER Storage format. See
Chapter 23. “Importing using a command line”.
Vector Datasets and Header Files (.erv)
49
•
DataType: DataType tells ER Mapper what type of dataset it is.
Values allowed are Raster or Vector. For example,
DataType = Vector
Raster dataset entries are detailed in Chapter 6, “Raster
datasets and header files (.ers)”.
•
•
ByteOrder: Indicates the byte ordering of the data. Can be
either:
•
MSBFirst - Most significant byte first.
•
LSBFirst - Least significant byte first.
For example,
ByteOrder = MSBFirst
Byte order is not significant for ASCII vector files.
Optional entries
•
CoordinateSpace block: Defines the dataset projection. See
“CoordinateSpace block” below.
•
VectorInfo block: Defines the dataset format. See “VectorInfo
•
DataFile: The name of the data file described by this header file.
The defaults to the same name (without the .erv extension) and
need only be specified if the data file has a different name. Some
applications like CDROMS will always enforce the dot if there is
no extension. You can have a header called ‘frog.erv’ which
contains the line ‘Datafile = “frog.”, and it will access the file
correctly.
•
LastUpdated: The date the file was last updated. For example,
block” below.
LastUpdated = Mon Dec 2 03:14:55 GMT 1991
•
SenseDate: The date the data was collected. For example,
SenseDate = Mon Feb 5 06:39:03 GMT 1990
50
Vector Datasets and Header Files (.erv)
CoordinateSpace
Block
The “CoordinateSpace” block specifies the datum and projection
type, the type of coordinates used, the units and rotation from true
North. For example,
CoordinateSpace Begin
Datum = “RAW”
Projection = “RAW”
CoordinateType = RAW
Units = “METERS”
Rotation = 0:0:0.0
CoordinateSpace End
Compulsory entries
•
Datum: The datum for the map projection. Allowable values are
RAW or one of the datums supported by ER Mapper (specified in
quotes). For example,
Datum = "RAW" or Datum = "AGD66"
See Appendix D “Supported map projections and datums” in the
ER Mapper User Guide for a list of available datums.
•
Projection: The map projection for the dataset. Allowable values
are RAW or one of the map projections supported by ER Mapper
(specified in quotes). For example,
Projection = "RAW"
or
Projection = "TMAMG53"
See Appendix D “Supported map projections and datums” in the
ER Mapper User Guide for a list of available map projections.
•
CoordinateType: Defines how coordinates are expressed. Note
that quotes are not used in this entry. Allowed types are:
•
RAW —Coordinates expressed as metres in master
coordinates.
•
EN —Coordinates expressed as Easting Northing coordinate
pair
•
LATLONG —Coordinates expressed as latitude and longitude in
degrees.
For example,
CoordinateType = RAW
Vector Datasets and Header Files (.erv)
51
Optional entries
•
Units: The unit of length used in the dataset (and the
RegistrationCoord block).
Allowed entries are:
•
"natural"
•
"METERS"
•
"U.S. SURVEY FOOT"
•
"IMPERIAL YARD"
•
other units defined in the control file
ERMAPPER\GDT_DATA\lenunits.dat.
The most common units are "METERS" and "natural". If the
units are not specified, they default to "METERS" for RAW datasets
and "natural" for non-RAW datasets. Here, "natural" means the
natural units for the projection. For example,
Units = "METERS"
•
Rotation: Rotation defines the rotation of the dataset from true
North in degrees counter-clockwise. For example,
Rotation = 0:0:0.0
defines no rotation from true North.
VectorInfo Block
The VectorInfo block contains information about the type of data in
the data file. All the entries are required.
•
Type: The type of data in the dataset. Allowed keywords are:
•
ERVEC
•
ERS (for backward compatibility only)
For example,
CellType = ERVEC
•
FileFormat: Only ASCII allowed in this release. For “ERS”,
“ASCII” and “BINARY” are allowed.
FileFormat = ASCII
•
52
Extents Block: Defines the vector data extents. See “Extents
block” below.
Vector Datasets and Header Files (.erv)
Extents Block
The Extents block defines the extents of the vector data by
specifying the coordinates of the top left and bottom right corners of
the dataset. It is made up of two sub-blocks. These are shown in the
example below,
Extents Begin
TopLeftCorner Begin
Eastings = 780810.6
Northings = 7982367.8
TopLeftCorner End
BottomRightCorner Begin
Eastings = 780810.6
Northings = 7982367.8
BottomRightCorner End
Extents End
The coordinates can be in Eastings/Northings or MetersX/MetersY or
Latitude/Longitude, compatible with the CoordinateType parameter.
For example,
MetersX = 8625.0
MetersY = 9225.0
or
Latitude = 34:16:54.98
Longitude = 140:34:3.2
Example vector
header files
Example “RAW” vector
dataset header file
The dataset header below is designed to overlay a 1000x1000 cell
“raw” raster datase Example georeferenced vector dataset header
“Newcastle_detail.erv”
Vector Datasets and Header Files (.erv)
53
Example of a dataset header for a georeferenced vector dataset.
DatasetHeader Begin
Version
= "3.0"
LastUpdated
= Thu Nov 28 05:42:01 GMT 1991
SenseDate
= Thu May 31 21:46:26 GMT 1990
DataSetType
= ERStorage
DataType
= Vector
ByteOrder
= MSBFirst
CoordinateSpace Begin
Datum
= "AGD66"
Projection
= "TMAMG54"
CoordinateType = EN
CoordinateSpace End
VectorInfo Begin
Type
= ERVEC
FileFormat
= ASCII
Extents Begin
TopLeftCorner Begin
Eastings
= 778062.95327
Northings
= 7997191.179595
TopLeftCorner End
BottomRightCorner Begin
Eastings
= 827209.421794
Northings
= 7930501.866287
BottomRightCorner End
Extents End
VectorInfo End
DatasetHeader End
Vector data file
54
Below is a simple vector data file containing a list of object
specifications. Note the following points:
•
ER Mapper vector data files list object data specifications in
ASCII format.
•
In general there is one object per line
•
Object specifications end with a full-stop (period) “.”
•
Consecutive fields in an object specification are delimited by a
comma, but there is no comma after the last field.
•
Real numbers may or may not contain a decimal point (that is,
may be reals or integers), but for efficiency reasons exponent
form may not be used.
•
ER Mapper vector data processing is not space sensitive - spaces
are simply ignored. Thus the indentation in text object
specifications is optional.
Vector Datasets and Header Files (.erv)
•
ER Mapper is sensitive to newline characters. Specifications for
objects of type point, box, map_box and oval must only take up
one line each. In text object specifications, each line of literal text
begins on a new line. Polyline, polygon and map_polygon objects
are not necessarily single line. Newline characters are inserted
after every 20 pairs of coordinates.
box(,111.437,726.765,222.055,810.293,0,1,0,255,0,0,0).
oval(,120.467,568.74,190.45,640.98,0,1,0,20,63,25,0).
polygon(,5,[319.127,196.253,355.247,412.973,325.9,548.423,321.385,647.753,319.1
27 ,582.285],0,1,0,0,-1,-1,-1,0).
poly(,2,[319.127,528.105,219.797,537.135],0,1,0,0,0,0,253,42,234,0).
poly(,6,[0.5149998,0.5865908,0.4599999,0.5923862,0.5499998,0.658068,0.5899998,0
.5 305681,0.4824998,0.3779545,0.3774999,0.3
586363],2,4.5,9,0,0,0,253,42,234,1).
point(a point,0.5474999,0.7488636,0,25,13,226,1).
map_box(“Name =
\”Scale_Bar/Tick\”\n”,0.65749,0.34704,0.8249999,0.4011363,0,1,0,- 1,-1,1,0,1).
map_polygon(“Name = \”Clip_Mask/Inside\”\n\n\”Color\” = \”253,0,9\”\n\”Border
Color\” =
\”254,254,254\””,4,[0.7149999,0.6310227,0.6874999,0.6503409,0.8549999,
0.6657954,0.8474999,0.5807954],0,1,0,0,-1,-1,-1,0,1).
vtext(,0.0575,0.4359091,0.0575,41.0659101,877.6655231,0.4359091,Courier,0,40.63
,1 ,0,0,0,253,13,22,1,[
“this is variable text, page relative”]).
The syntax for the object types in ER Mapper vector data files is
described below. It is important to note that the syntax is line end
sensitive but not space sensitive. The italicized specifiers are
described after t\e object syntax.
point
Syntax: point (attribute, x, y, spare, r, g, b, page).
For example:
point ("a point", 0.5474999,0.7488636,0,25,13,226,1)
box
Syntax: box (attribute, ltx, lty, rbx, rby, fill, width, pen, r, g, b,
page).
For example:
box ("a box", 58236.3500.56, 59236.35, 62600.56, 0, 0,
1, 255, 0, 0, 0)
oval
Syntax: oval (attribute, ltx, lty, rbx, rby, fill, width, pen, r, g, b,
page).
For example:
Vector Datasets and Header Files (.erv)
55
oval ("a circle", 250, 150, 300, 100, 3, 0, 0, -1, -1 1, 0)
fixed text
Syntax: text (attribute, x, y, font, style, size, nlines, just, angle, pen,
r, g, b, page, [
"line_of_text",
"line_of_text"]).
For example:
text ("A line of text", 5836.35, 6100.56, HelveticaBold, 1, 12, 1, 0, 0, 1, 0, 0, 255, 1,[
"This is fixed text."])
variable text
Syntax: vtext(attribute, x, y, ltx, lty, rbx, rby, font, style, size,
nlines, just, angle, pen, r, g, b, page, [
"line_of_text",
"line_of_text"]).
For example:
vtext(,0.0575,0.4359091,0.0575,41.0659101,877.6655231,
0.4359091, courier,0,40.63,1,0,0,0,253,13,22,1,[
“this is variable text, page relative”])
polyline
Syntax: poly (attribute, npoints, [X1, Y1, . . . Xn, Yn], end, width,
pen, reserved, curved, fill, r, g, b, page)
For example:
poly (, 2, [0.5, 0.5, 2, 2], 2, 3, 1, 0, 0, 1, 220,0,
220, 1)
polygon
Syntax: polygon (attribute, npoints, [X1, Y1, . . . Xn, Yn], fill, width,
pen, curved, r, g, b, page)
For example:
polygon(,5,[319.127,196.253,355.247,412.973,325.9,548.
423,321.385 ,647.753,319.127,582.285],0,1,0,0,50,0,22
0,0)
56
Vector Datasets and Header Files (.erv)
map_box and map_polygon
MapBox and MapPoly objects have the same syntax as the Box and
Polygon objects respectively except they include a fast_preview
parameter before the page parameter. The attribute field contains
information used to specify the map composition object including the
name of the ‘legendrules’ file and any parameter that the user
specifies differently from the default. See Chapter 19, “Map
composition files (.ldd)” for more information about map objects. For
example,
map_box(“Name =
\”Scale_Bar/Tick\”\n”,0.65749,0.34704,0.8249999,
0.4011363,0,1,0,-1,-1,-1,0,1).
map_polygon(“Name = \”Clip_Mask/Inside\”\n\n\”Color\”
= \”253,0,
9\”\n\”Border Color\” =
\”254,254,254\””,4,[0.7149999,0.6310227,
0.6874999,
0.6503409,0.8549999,0.6657954,0.8474999,0.5807954],0,
1,0,0,-1,-1,-1,0,1)
SPECIFIERS USED IN OBJECT DEFINITIONS
name
full name
type
comments
angle
angle of text object
real
Angle of text object in degrees (0 - 360)
clockwise.
attribute
text attribute or label
alpha numeric
characters
Text that will be associated with the object. Must
use only alphanumeric characters.
end
line end style
integer
End of line style, where:
curved
curve
boolean
0
= plain
1
= arrow - end of line
2
= arrow - beginning of line
3
= arrow - both ends of line
Set polyline or polygon spline condition on or
off.
0
= off (straight lines)
1
= on (curved lines)
font
font
text
The name of the font used in a text object.
fill
fill style
integer
An integer specifying the object fill style. Can be
0 to 19.
just
text justification
integer
Justification of a text object, where:
0 = left
1 = centre
2 = right
Vector Datasets and Header Files (.erv)
57
SPECIFIERS USED IN OBJECT DEFINITIONS
name
full name
type
comments
line_of_ text
single line of a text
object
text including
punctuation
The text that shows on the screen or output
device. Punctuation is allowed.
ltx
left top x
real
lty
left top y
real
rbx
right bottom x
real
The coordinates of the object, in the units
specified in the dataset header file. Raw
coordinates are normally in the range zero to a
few thousand whereas E/N are in the order of
millions eg. 6123123.567.
rby
right bottom y
real
x
x coordinate
real
y
y coordinate
real
nlines
number of lines
integer
The number of lines in a text object
npoints
number of points
integer
Number of points in a polyline or polygon
page
page relative or map
relative
boolean
0 indicates object coordinates are in image
coordinates; 1 indicates object coordinates are
relative to the page dimensions.
pen
pen style
integer
An integer specifying the pen pattern. Can be 0
to 23. The styles are those shown in the
Annotation line style dialog box.
reserved
reserved
0
Used by ER Mapper. Set to zero.
r, g, b
red, green and blue
integer
components of the color -1 to 255
0 to 255 specifies amount of color component. 1,-1,-1 indicates default layer color.
size
text size
real
Size of a text object in points.
spare
spare
0
Not used at this time - set to zero
style
text style
integer
Ignored. Included in font specification.
width
line width
real
The thickness of the line in points.
58
The coordinates of the bottom left of the first
line of text.
Vector Datasets and Header Files (.erv)
Dynamic Links Program Interface
Introduction
This section provides the user with information regarding the
Dynamic Links Program Interface.
Non-Raster data
Dynamic Links are used to access non-raster data from outside
ER Mapper. The data can be of any kind, such as vector data stored
in a GIS, tabular data from a spreadsheet or point data from a DBMS.
ER Mapper PostScript
The language used by ER Mapper for Dynamic Links is PostScript.
External data from a source is transformed into ER Mapper
PostScript by the appropriate Dynamic Link. This is then further
processed and merged by ER Mapper with other Dynamic Link and
Raster layers.
Editable links
ER Mapper also supports Read/Write dynamic links, to enable direct
editing of external data in ER Mapper image windows.
Flexible connections
Dynamic Links are true connections to external systems, querying
them for the data required. The complexity of the link and the source
and format of the data varies and the differences are accommodated
by the flexibility of the Dynamic Link interface. Separate Dynamic
Link connections to external data are performed by independent
programs which are controlled by a menu file and Dynamic Link
manager. To create a new Dynamic Link new programs and a new
menu option have to be added.
Refer to the “Dynamic links menu” chapter in this manual.
Multiple links
Any number of Dynamic Links can be added. Indeed, multiple
Dynamic Links to the same system are possible.
Ready-made links
ER Mapper is supplied with a variety of ready-made links to popular
systems and data formats. If there is already a link to the type of
data you want to include you can select the appropriate Dynamic
Link layer from the menu. If not, a new link must be constructed to
transform your data into ER Mapper PostScript format.
Triggering links
Dynamic Links are triggered each time the user initiates a display
(for example by pressing zoom) or printing.
Examples
The Dynamic Link examples in this chapter have been written in a
combination of Shell Script and PostScript and it is assumed that you
are familiar with Shell Script programming. Links can however be
written in any language as long as they output PostScript to stdout.
An example of a Dynamic Link written in “C” is “ermps_dxf.c” which
creates a Dynamic Link to “.dxf” files. The C source to this program,
and the source to other example Dynamic Links, may be found in the
“ERMAPPER\examples” directory.
Dynamic Links Program Interface
59
Georeferenced
and Page Relative
layers
While ER Mapper can incorporate virtually any type of non-raster
data, the type of data displayed falls into one of two distinct
categories. These are:
•
Georeferenced data
•
Page relative data
Georeferenced data
In a Georeferenced layer, data is positioned accurately over a raster
image using geographical coordinates. The vector image zooms and
moves whenever the raster image is manipulated. You might have
vector information such as a road network from a GIS system or
pollution density readings at different locations stored in a DBMS
table. The Dynamic Links to ARC/INFO are examples of
Georeferenced Data layers.
Page relative layers
In a page relative layer, text or graphics are positioned relative to
the image window, not matched to the position of any raster data
coordinates. Zooming and changing the window extents have no
effect on the positioning of the layer.
All the dynamic links in the PostScript submenu in the Edit / Add
Vector Layer menu are this kind of Dynamic Link.
ER Mapper
ER Mapper
Helping people manage the earth
Helping people manage the earth
WA
SA
a)
WA
NT QLD
NSW
VIC
b)
Comparison between georeferenced layers and page relative layers:
a) The Georeferenced layer showing state boundaries and state
names zooms and moves with the raster layer of Australia; b) The
Page relative layer with “ER Mapper Helping people manage the
earth” always appears in the top left hand corner.
Dynamic Link layer
buttons
60
Dynamic Link layer options are listed in the lower part of the Edit /
Add Vector Layer menu in ER Mapper’s Algorithm dialog box (see
below). When an option is chosen from the menu a new layer is
added.
Dynamic Links Program Interface
Dynamic Link layers
Dynamic link layer buttons
Dynamic Link layers can have the following buttons associated with
them. Parameters in the dynamic links menu file determine which
will appear.
These parameters are referred to briefly below and are
described in detail in the section “Adding the menu option”
later in this chapter.
•
For selecting a data source: either the Dynamic Link chooser
button
for selecting from a list of items or the Dataset
chooser button
for choosing a data file from a list with file
extensions. For example, the “AutoCAD DXF” layer uses the
Dataset chooser button to choose a dataset with a “.dxf”
extension, while in the “ARC/INFO direct link via ARC/PLOT” layer
the Dynamic Link chooser button is used to select from a list of
ARC/INFO covers. The “link chooser” parameter specifies which
of the two buttons to include or it is possible to omit these
buttons altogether if the data source is set specifically in the
dynamic link. See “Chooser program” and “Link chooser
parameter”.
Dynamic Links Program Interface
61
•
The Color chooser button
for selecting the default color
of the layer. In some layers this color will be overridden by the
linked data.
•
The Edit button
is only available for read/write dynamic
links: Annotation/Map Composition, Tables of data shown as
Circles links, Regions links and ARC/INFO Overlay layers are
examples. These vector layers can be edited using a variety of
drawing tools. The button is specified by the “Edit flag”
parameter.
To use an existing Dynamic Link
Thus, for the ER Mapper user, the procedure for displaying an
existing Dynamic Link in an algorithm is to:
•
in the Algorithm dialog box, choose the appropriate Dynamic
Link layer option from the Edit / Add Vector Layer menu
•
if a Dataset chooser button or Dynamic Link chooser button
is available, use it to select a data source
The use of individual existing Dynamic Links is covered in
Dynamic links (vector layers) in the ER Mapper User Guide.
This chapter details how to construct new Dynamic Links, with their
controlling menu option entry and link programs, and using existing
links as examples.
Inside a Dynamic Link
The previous section looked at Dynamic Links as they appear to the
user. In the sections that follow we will look at how a Dynamic Link
is constructed.
A Dynamic Link is added as a separate layer. Each link is controlled
by an entry in the dynamic link menu file which specifies program
calls and other parameters. A Dynamic Link consists of a maximum
of 3 procedures. These are:
•
Choosing the data source (optional)
•
Initializing the link (optional)
•
Extracting and converting the data to PostScript.
These procedures are outlined briefly below and detailed in the
pages that follow.
62
Dynamic Links Program Interface
user
1
menu
entry
list of
sources
target
data
source
2
4
5
ER Mapper
3
Dynamic Link
Chooser
Initializer
PostScript
Generator
6
display
or
hardcopy
image
How a Dynamic Link works:
1. The user selects the Dynamic Link menu option, setting up the
Dynamic Link;
2. The chooser displays a list of sources;
3. The user selects a source;
4. The Initializer queries the target source about the data extents and
map projection;
5. The PostScript Generator asks for and receives the required data,
converting it into PostScript;
6. The data, in PostScript format, is merged with other layers and sent
to the output device.
Choosing the data source
In a Dynamic Link, the type of data source is not restricted. Thus
ER Mapper must be passed a list of the sources to be specified. For
example, all files with a particular extension may be candidates for
the link, there may be a set list of possibilities or there may be no
choice at all. By the end of this step a particular data source will have
been specified. For example, with the ARC/INFO Dynamic links the
cover to be extracted is chosen in this step.
Initializing the link
In this step ER Mapper takes information such as the image extents
and current map projection and queries the potential data source for
corresponding information. It checks if the data is compatible with
other displayed data.
Dynamic Links Program Interface
63
Extracting the data
The relevant data is converted into PostScript and displayed with any
raster and vector layers and other Dynamic Link layers in the current
algorithm.
Creating a
Dynamic Link
To create a new Dynamic Link you will need to do the following (in
no particular order):
•
•
ER Mapper PostScript
add a menu option to the dynamic links menu file to access and
specify the new link from inside ER Mapper
write the PostScript generation program to convert the data to a
form compatible with ER Mapper
•
if required, construct a link chooser so the user can select the
data source from a list of options
•
where necessary, write an initialization program to set up the
link.
All Dynamic Links must convert data into PostScript. Thus
understanding PostScript interpretation is an important part of
creating new Dynamic Links.
In addition, since PostScript is the language on which Dynamic Links
are based, it is the logical choice for creating files for display. Many
drawing packages can produce their output in PostScript or you can
write a file directly in PostScript yourself.
ER Mapper, however, does not interpret PostScript as a fixed page
size. Instead it is set up to display images to maximum device
resolution and to cope with a changing output canvas size.
These differences are detailed in the chapter on PostScript.
A number of ready made Dynamic Links are available for accessing
PostScript files. There are links set up to handle files output in
standard PostScript from other packages and links set up for files
written with PostScript interpretation by ER Mapper in mind.
Looking ahead
64
The following sections describe:
•
Adding The Menu Option: to the Dynamic Links menu file
•
Chooser Program: the alternative ways available for choosing
data
•
Link Initialization: the program interface for the link initializer
•
PostScript Generation: the program interface for the data
extraction and PostScript generation program
Dynamic Links Program Interface
•
Adding the menu option
Example Dynamic Links: the full code for existing Dynamic Links
Dynamic Link menu options are specified in the ASCII file
“dynamiclinks.erm” in the “ERMAPPER\config” directory. The options
listed in this file appear in the lower part of the Edit / Add Vector
Layer menu in the Algorithm dialog box. To add your dynamic link
option to the menu, you add a single-line menu entry in this file. The
entry specifies the data source, link initialization program and
PostScript generation program. For example, the entry for the
dynamic link to a Microstation DGN file is the following:
"MicroStation DGN File" "DGN Link" "ermps_dgn"
TRUECOLOR ".dgn"
"erminit_dgn"
As another example, the entry for an editable link is:
"Table Circles with Rotation"
"Table of Data with
Rotation Link"
"ermps_table_circle" MONOCOLOUR
".tbl" "erminit_any" "EDIT"
"erm_link"
Briefly the parameters are:
•
Menu option: The text to be displayed on the menu. In this case:"
Table Circles with Rotation"
•
Description: A short description of the link shown in the layer in
the Algorithm dialog.
"Table of Data with Rotation Link"
•
PostScript generation program: The program for creating the
PostScript for display by ER Mapper.
"ermps_table_circle"
•
PostScript type: (Optional). Either MONOCOLOUR or
•
Link chooser: (Optional). The data source for the dynamic
•
Initialization program: (Optional). A program for setting up the
coordinate space and extents for the link.
TRUECOLOUR.
link.".tbl"
"erminit_any"
•
"EDIT":(Optional). Indicates a Read/Write (editable) link.
•
8. Edit program: (Optional, but must be present if 7. is present).
The edit program.
"erm_link"
Dynamic Links Program Interface
65
The ‘dynamiclinks.erm’ file and these parameters are described
in full in the “Dynamic links menu” chapter.
Chooser program
Name and Directory
The link chooser program can be written in any programming
language. Those supplied with the earlier Unix versions of ER Mapper
were mostly written in shell script. Link initialization programs are
typically stored in the $ERMBIN directory. The program name must
not start with “$” or “.”.
Arguments
No arguments are passed to the chooser program.
Output
The data chooser program outputs a list of choices to stdout.
The example program below could be used in a dynamic link that
requires a distance parameter, such as a grid spacing, to be set. The
program passes the list of possible values to the chooser program.
One of these is then selected by the user and copied to argument 15.
#! /bin/sh
#
# Returns list of possible values
#
cat << EOF
Variable
10 meters
100 meters
500 meters
1,000 meters (1km)
2,500 meters (2.5km)
5,000 meters (5km)
10,000 meters (10km)
25,000 meters (25km)
50,000 meters (50km)
100,000 meters (100km)
1,000,000 meters (1,000km)
EOF
66
Dynamic Links Program Interface
A second example extracts the list from a table.
#!/bin/sh
#
# 1. Assumes that sqlplus is accessible
# 2. Assumes that headings are turned off in sqlplus
#
# Returns all tables within Oracle accessible to ER Mapper
#
# You can use just about any SQL based logic to select a list of
# tables or views to be displayed under ER Mapper.
#
# This particular example expects to find a table titled
# "ERMAPPER_LAYERS" which will contain one column which will
# be a list of all tables in the format of 3 columns
# (Easting Northing Z-Value) which may be displayed with
# ER Mapper.
#
# You can create any sort of SQL access into Oracle to display
# tabular data; this link is an example of how to do so.
sqlplus << EOF
SELECT * FROM ERMAPPER_LAYERS
QUIT
EOF
exit $?
Link initialization
If the sixth parameter in the menu file entry is present, the link
initialization program specified is called to check the suitability of the
source data. If no program is specified ER Mapper assumes that the
source data is always compatible.
The link initialization program runs at some time after the chooser
program and before the PostScript generation program. It may be
called by ER Mapper any time the data compatibility may have
changed, for example, when a layer in a different coordinate system
has been switched on.
Name and Directory
The link initialization program can be written in any programming
language. It is typically stored in the “ERMBIN” directory. The
program name must not start with “$” or “.”.
Dynamic Links Program Interface
67
Arguments
ER Mapper always passes 15 arguments to the link initialization
program which may use them or ignore them as required. These
arguments are also passed to the PostScript generation program
(see next section). This means that the same program can be used
for both link initialization and PostScript generation. When the
program is being called for initialization the first field is set to
“mapinfo”.
The fifteen arguments are:
Number
Name
Example
Comment
1
COMMAND
“mapinfo”
“mapinfo” for link initialization
“postscript” for PostScript generation
2
DATUM
“AGD66”
Datum, from the coordinate database
3
PROJECTION
“TMAMG54”
Projection, from the coordinate database
4
COORDTYPE
“EN”
“EN”, “LL” or “RAW”
5
UNITS
“METERS”
The preferred units
6
ROTATION
0
Rotation from North in radians
7
TLX
100
Top Left X value in x/easting/latitude
8
TLY
200
Top Left Y value in y/northing/longitude
9
BRX
300
Bottom Right X in x/easting/latitude
10
BRY
400
Bottom Right Y in y/northing/longitude
11
CANVASWIDTH
500
Current canvas width in pixels
12
CANVASHEIGHT
600
Current canvas height in pixels
13
DPIX
83.1272727
Device X dots per inch
14
DPIY
83.1272727
Device Y dots per inch
15
FILESPEC
“Roads”
File name or user choice or fixed
argument from link chooser step
Output
The link initialization program outputs 11 fields to STDOUT. The first
ten fields are the same as those passed to the program, while the
eleventh is optional and should only be specified if the link is capable
of handling more than one coordinate system.
Fields must be separated by a space (or tab) and any fields
containing imbedded blanks must be enclosed in quotes ("). Quotes
are not permitted within any argument.
68
Dynamic Links Program Interface
The arguments returned from the link initialization program are:
Number
Name
Example
Comment
1
COMMAND
“mapinfo”
“mapinfo” for link initialization
“postscript” for PostScript generation
2
DATUM
“AGD66”
Datum, from the coordinate database
3
PROJECTION
“TMAMG54”
Projection, from the coordinate database
4
COORDTYPE
“EN”
“EN”, “LL” or “RAW”
5
UNITS
“METERS”
The preferred units
6
ROTATION
0
Rotation from North in radians
7
TLX
100
Top Left X value in x/easting/latitude
8
TLY
200
Top Left Y value in y/northing/longitude
9
BRX
300
Bottom Right X in x/easting/latitude
10
BRY
400
Bottom Right Y in y/northing/longitude
11
MULTI-C SPACES
MULTI
Can handle multiple coordinate spaces
flag
Errors
Errors within the link initialization program can be reported by
printing an error message to STDERR and exiting the program with
a non-zero exit code. ER Mapper will check the exit code of the
initialization program and if it is non-zero it will look for a message
in STDERR.
Example
initialization
program
An example link initialization program “erminit_any” from the
“$ERMBIN” directory (ERMAPPER\bin\win32). This program simply
echoes the link arguments back to ER Mapper.
void main(int argc,char **argv)
{
int i;
/* Make sure we have the correct count for dynamic
link aguments */
if(argc < 16){
fprintf(stderr,"Expected 15 arguments got
%d\n",argc - 1);
exit(1);
}
/* output the first 5 arguments with quotes */
for(i = 1; i < 6;i++)
fprintf(stdout,"\"%s\" ",argv[i]);
/* output the last 7 without quotes */
Dynamic Links Program Interface
69
fprintf(stdout, "%s "/*rotation*/
"%s
"/*top x*/
"%s
"/*top y*/
"%s
"/*bottom x*/
"%s
"/*bottom y*/
"%s
"/*dpi x*/
"%s
"/*dpi y*/
"MULTI",argv[6],argv[7],argv[8],argv[9],argv[10],
argv[13],argv[14]);
fflush(stdout);
exit(0);
}
PostScript
generation
ER Mapper calls the PostScript conversion program to create
PostScript. The program name is specified in the third parameter in
the entry in the dynamic link menu file. This is the main part of the
link. The program extracts data from the source specified in the link
chooser stage and converts it into PostScript so that it can be
displayed by ER Mapper. For example, the ‘ermps_dxf’ program
reads an AutoCAD DXF file and converts it into PostScript which may
be integrated with other data by ER Mapper.
This section describes how to create this kind of PostScript
generation program. It is assumed you have some knowledge of the
PostScript language.
More detailed information about writing PostScript for
ER Mapper can be found in the “Postscript” chapter of this
manual.
Name and Directory
By convention, the names of PostScript conversion programs begin
with “ermps_” and the programs are stored in the “$ERMBIN”
directory. The program can be written in any programming language
(shell script and C are common choices).
Arguments
ER Mapper passes 15 arguments to the PostScript generation
program, which can use or ignore them as required. These are the
same arguments that are passed to the link initialization program,
with the first argument is set to “postscript”. See the section “Link
initialization” earlier in this chapter for a full description of the
parameters.
Of particular interest are the following parameters:
•
70
CANVASW (argument 11) - the width in pixels for the canvas
Dynamic Links Program Interface
•
CANVASH (argument 12) - the height in pixels for the canvas
•
DPIX (argument 13) - the DPI in X for the output device
•
DPIY (argument 14) - the DPI in Y for the output device
When creating your output PostScript, you can assume that you are
rendering into an output canvas which is CANVASW pixels across and
CANVASH pixels down, with an origin of (0,0) at the bottom-left
hand corner of the canvas.
Thus, the PostScript code:
%!
0 0 moveto
WidthI HeightI lineto
stroke
will draw a line from the bottom-left hand corner of the image to the
top-right hand corner of the image. You should always start your
PostScript output code with the characters "%!".
Notice the use of two variables "WidthI" and "HeightI". These are
defined within the PostScript dictionary by ER Mapper, allowing an
application to know the size in device pixels for the output image.
These and other variables are described in the “Postscript”
chapter of this manual.
Output
The PostScript generation program returns PostScript to standard
output (STDOUT).
Errors
Errors within the PostScript generation program can be reported by
printing an error message to STDERR and exiting the program with
a non-zero exit code. ER Mapper will check the exit code and if it is
non-zero it will look for a message in STDERR.
Dynamic Links Program Interface
71
A simple example of a PostScript generation program, “ermps_date”
is given below. It is written in C and outputs PostScript to STDOUT.
** PURPOSE:To Produce the date and time in the bottom left side of the image
#ifndef lint
static char *sccsident="@(#)%M%:%I%%D%Copyright Earth Resource Mapping
1989-95";
#endif
#include "ERS.h"
#include <time.h>
void main(int argc,char **argv[])
{
char *p_ascitime;
struct tm *p_tm;
time_t tm;
time(&tm);
p_tm = localtime(&tm);
p_ascitime = asctime(p_tm);
fprintf(stdout,"%%!PS-Adobe-1.0\n"
"%%\n"
"/FS HeightI 20 div def"
" %% font size = 1/20th of image height\n"
"0 setgray
%% set gray level (== black)\n"
"%% <Date>\n"
"/Helvetica findfont FS 0.4 mul scalefont setfont\n"
"FS FS FS .6 mul sub moveto\n"
"%s show\n"
"showpage\n",p_ascitime);
exit(0);
}
Printing dynamic
links
Dynamic Links are fully supported in hardcopy generation. The
ER Mapper hardcopy engine may have to strip print “tiles” or “strips”
of the image if the user requests an image that is larger than the
hardcopy device. The entire strip printing issue is hidden from
Dynamic Links. The following points may be of interest:
•
72
Your Dynamic Link will be called once only to create the
PostScript for the entire image in the layer, regardless of how
many hardcopy strips are required to create that image.
Dynamic Links Program Interface
•
MONOCOLOUR vs
TRUECOLOUR
links
Your PostScript code may be rendered into multiple canvases,
one for each strip (and indeed one for each sub-strip if strips are
larger than available memory for the PostScript engine).
However, at all times your PostScript code “sees” the entire
image.
PostScript can be either MONOCOLOUR or TRUECOLOUR. The type of
PostScript is specified in the menu entry for each Dynamic Link. In
most cases you will only want to use MONOCOLOUR. This means that
the entire layer will be displayed in a single color which is chosen by
the user using the Color button.
In TRUECOLOUR PostScript the color is specified in the PostScript
code itself and any number of colors can be used in the one layer.
However, this kind of PostScript takes longer to process, so use
MONOCOLOUR wherever possible.
If TRUECOLOUR PostScript is linked using a MONOCOLOUR link, it is
displayed as if it were in monochrome in the color specified by the
Color button.
Batch Script
Chooser
With this option you can specify a batch script to run to determine
the source of the data. The syntax is:
"$$SCRIPT=batchfile.erb"
You can also use the $DEFAULT keyword which is replaced with the
last value returned by the batch script. The syntax is:
"$$SCRIPT=batchfile.erb $DEFAULT"
Refer to the “Batch scripting and wizards” chapter for more
information.
Debugging
dynamic lines
To assist you with creating and debugging new Dynamic Links there
are a number of links which echo back the values of the link
parameters and display them on the screen. These can be found on
the Example User Dynamic Links submenu. They are:
•
Show arguments for No Parameter
•
Show arguments for Dataset Chooser
•
Show arguments for Fixed Parameter
•
Show arguments for $$ALG Parameter
•
Show arguments for Link Chooser
•
Show arguments for External Link Chooser
•
Show arguments for Script Link Chooser
Dynamic Links Program Interface
73
The links correspond to the categories of syntax for the link
chooser parameter in the dynamic links menu file (see the
“Dynamic links menu” chapter).
The Dynamic Link menu file entries for these links are shown below.
"Example User Dynamic Link" "Example User Dynamic Link" "ermps_example"
MONOCOLOUR "$ER Mapper"
"Show arguments for No Parameter" "No Parameter Link" "ermps_info" MONOCOLOUR
"Show arguments for Dataset Chooser" "Dataset Chooser Link" "ermps_info"
MONOCOLOUR ".ers"
"erminit_ers"
"Show arguments for Fixed Parameter" "Fixed Parameter Link" "ermps_info"
MONOCOLOUR "$variable"
"Show arguments for $$ALG Parameter" "$$ALG Parameter Link" "ermps_info"
MONOCOLOUR
"$$ALG"
"Show arguments for Link Chooser" "Link Chooser Link" "ermps_info" MONOCOLOUR
"erm_choose_en_grid"
"Show arguments for External Link Chooser" "External Link Chooser Link"
"ermps_info" MONOCOLOUR "$$CHOOSER=erm_xgettext -s 30 -p \"Enter some text\" name \"External Link Chooser\""
"Show arguments for Script Link Chooser" "Script Link Chooser Link" "ermps_info"
MONOCOLOUR
"$$SCRIPT=Dlink_Chooser.erb $DEFAULT"
To use these links to develop your own dynamic link, substitute your
link chooser and initialization program names for the fourth and fifth
arguments of the appropriate link entry. For example, to see the link
parameters passed to the “MicroStation DGN File”, substitute the link
chooser “.dgn” and the initialization program called “erminit_dgn”
for the fourth and fifth arguments in the “Show arguments for Link
Chooser” Dynamic Link menu entry. Change the PostScript type from
MONOCOLOUR to TRUECOLOR. If a Chooser button is available as
part of your link you will have to select a data source to display the
arguments.
“MicroStation DGN File” menu entry in ERMAPPER\config\dynamiclinks.erm
1. Menu option
"MicroStation
DGN File"
2. Description 3. PostScript
generation
program call
"DGN
link"
"ermps_d
gn"
4. PostScript
type
TRUECOL
OR
5. Link chooser
(optional)
".dgn"
6. Initialization
program call
(optional)
"erminit_d
gn"
“Show arguments for Link Chooser” menu entry in ERMAPPER\config\dynamiclinks.erm
1. Menu option
"Show
arguments for
Link Chooser"
74
2. Description 3. PostScript
generation
program call
"debug
dynamic
link"
"ermps_i
nfo"
4. PostScript
type
TRUECOL
OR
5. Link chooser
(optional)
".dgn"
6. Initialization
program call
(optional)
"erminit_d
gn"
Dynamic Links Program Interface
Example 1 - Example User
Dynamic Link
This is an example of a link which passes a string from the dynamic
link menu file to the PostScript generation program. The string
specified in the fifth parameter in the menu entry is inserted into a
program written in C and ER Mapper PostScript. This is a page
referenced layer that draws on the screen without taking the
coordinate system or data extents into account. There is no Chooser
button available for the layer because the layer is generated by the
PostScript generation program using the text “ER Mapper” passed by
parameter five.
ER Mapper
The link draws a box on the screen with the word “ER Mapper”
rotated through the center as follows (actually rotated twelve times).
ER Mapper
ER Mapper
ER Mapper
This layer may be displayed by selecting the Example User
Dynamic Links / Example User Dynamic Link option from the
Edit / Add Vector Layer menu in the Algorithm window. This
option calls the Dynamic Link filter program ‘ermps_example’ to
create the PostScript code for this link. There is an example
algorithm
Functions_And_Features\Dynamic_Links\User_Example_Dy
namic_Link which uses this example Dynamic Link.
The complete code for this example link is given below. It has been
implemented in C to demonstrate just how easy it is to create a
Dynamic Link to ER Mapper. More sophisticated examples may be
found in the ERMAPPER\examples directory; in particular the
ermps_dxf.c program which creates a Dynamic Link to DXF vector
files.
The ermps_example Dynamic Link will print any word as the text.
Change the fifth parameter in the Example User Dynamic Link
menu entry in the dynamiclink.erm configuration file.
It should be noted that this example Dynamic Link always draws a
box the size of the image whereas most Dynamic Links extract and
display a particular region of interest which changes as the ER
Mapper user zooms in and out.
Dynamic Links Program Interface
75
Dynamic link menu entry in ‘dynamiclinks.erm’
Dynamic link menu entry ERMAPPER\config\dynamiclinks.erm
1. Menu option
"Example User
Dynamic Link"
2. Description
""
3. PostScript
generation program
call
4. PostScript 5. Link chooser
type
(optional)
"ermps_examp
le"
MONOCO
LOUR
"$ER
Mapper"
PostScript generation program ‘ermps_example’
/*****************************************************
**
** PURPOSE:
** An example dynamic link. This one draws a box the
size of the
** image with a cross through it, and the rotates the
word
** "FileSpec" (arg 15)through the image. More advanced
examples
** such as "ermps_dxf.c" may be found in
$ERMAPPER/examples
**
** Arguments
** 1 COMMAND
# should be "postscript"
** 2 DATUM
# geodetic datum name
** 3 PROJECTION
# projection name
** 4 COORDTYPE
# type of coordinates (EN, LL or RAW)
** 5 UNITS
# Units (eg. METERS)
** 6 ROTATION
# rotation
** 7 TLX
# top left x coordinate
** 8 TLY
# top left y coordinate
**9 BRX
# bottom right x coordinate
** 10 BRY
# bottom right y coordinate
** 11 CANVASWIDTH # window width (0 on init)
** 12 CANVASHEIGHT# window height (0 on init)
** 13 DPIX=$4
# x dots per inch (0 on init)
** 14 DPIY=$5
# y dots per inch (0 on init)
** 15 FILESPEC
# file spec or choice string
**
** EDITS:
******************************************************
*/
#ifndef lint
static char *sccsident="@(#)%M%:%I%%D%Copyright Earth
Resource Mapping 1989-96";
#endif
#include "ERS.h"
76
Dynamic Links Program Interface
#include "ps_util.h"
int main(int argc, char **argv)
{
erm_dlinkargs dlink;
if(!erm_initdlinkargs(argc,argv,&dlink))
exit(1);
if(!dlink.filespec ||
(dlink.filespec && !strlen(dlink.filespec)))
{
fprintf(stderr, "%s: Filespec argument is null",
argv[0]);
}
/* Now generate the postscript code */
fprintf(stdout, "%%!\n"
"%% A simple example ER Mapper Dynamic Link\n"
"%%This draws a box the exact size of the
resultant image\n"
"%%that ER Mapper is to generate, with a cross
through it.\n"
"%%It then draws some fancy rotated text\n"
"\n"
"%% value was in 72 point\n"
"/from72pt { %lf 72 div mul } def\n"
"\n"
"%% First, draw a cross through the image
window\n"
"%% make sure is always 10 point (72 dpi) wide\n"
"%% regardless of device actual dpi\n"
"2 from72pt setlinewidth\n"
"0 0 moveto\n"
"0 0 moveto\n"
"WidthI 0 lineto\n"
"WidthI HeightI lineto\n"
"0 HeightI lineto\n"
"0 0 lineto\n"
"stroke\n"
"0 0 moveto\n"
"WidthI HeightI lineto\n"
"stroke\n"
"WidthI 0 moveto\n"
"0 HeightI lineto\n"
"stroke\n"
"\n"
Dynamic Links Program Interface
77
"%% now draw the variable (arg 15) as rotated
text\n"
"%% Text will always be this point regardless of
image"
"%% size\n"
"/Helvetica-Bold findfont 32 from72pt scalefont
setfont \n"
"\n"
"/oshow %% stack: grey (string)\n"
"{\n"
"true charpath \n"
"gsave setgray fill grestore\n"
"stroke\n"
"} def\n"
"\n"
"/circleofERM\n"
"{\n"
"30 30 330\n"
"{\n"
"gsave\n"
"dup 345 divexch %% for the setgray\n"
"rotate 0 0 moveto\n"
"(%s) oshow\n"
"grestore\n"
"} for\n"
"} def\n"
"\n"
"%% begin program\n"
"WidthI 2 div HeightI 2 div translate\n"
"\n"
".5 from72pt setlinewidth\n"
"circleofERM\n"
"0 0 moveto\n"
"(%s) show\n"
"\n"
"showpage\n",
dlink.dpix,
dlink.filespec,
dlink.filespec);
exit(0);
}
In a monocolour overlay the color is set by the color button. So
in the code above, ‘black’ means full color and ‘white’ is no color.
Example 2 - Table of data
shown as circles
78
This link reads a file containing a table with three columns which are
an Easting, a Northing and a Value. For each row of data, the link
draws a circle of diameter Value at the Easting-Northing position.
Dynamic Links Program Interface
Output
The figure below shows the output for a sample table of data. In
reality the table would not have a heading row.
eastings
northings
value
461200
6200000
0.85
462900
6198000
0.65
463200
6180000
0.25
464100
6178000
1.3
+
+
+
+
The standard ER Mapper dataset chooser is called because of the
“.ext” syntax of the fifth parameter. All “.tbl” files stored in the
$ERMDSDIR path are listed by the Chooser.
Dynamic link menu entry ERMAPPER\config\dynamiclinks.erm
1. Menu option
"Table of data
shown as Circles"
3. PostScript
generation program
call
"ermps_table_
circle"
Dynamic Links Program Interface
4.
PostScript
type
MONOC
OLOUR
5. Link
chooser
(optional)
".tbl"
6. Initialization
program call
(optional)
7. Edit
flag
(optional)
"erminit
_en0"
79
Initialization
The Link Initialization program tells ER Mapper that the link is only
compatible with an EN coordinate system by setting the projection
and unit arguments to appropriate values. It does not actually look
at the table file but assumes that the values are Eastings-Northings.
The projection argument cannot simply be echoed back because, if
this is the first layer, the projection will be set to default RAW
projection. The other arguments are simply echoed back so the
entire table is used regardless of the data extents. Note that all
fifteen arguments are read in, even though they are not all used, and
eleven arguments are output to STDOUT as required. The program
is written in shell script.
Link initialization program ERMAPPER\bin\win32\/erminit_en0
/*****************************************************
*************************
** PURPOSE:This program accepts the arguments passed
from ER Mapper, checks
** that the correct number of arguments have been passed
(i.e. 16), then outputs
** the arguments in the correct format ready for
processing by the PostScript
** generation program.
******************************************************
************************/
int main(argc, argv)
int argc;
char **argv;
/*
** This program accepts the arguments passed from ER
Mapper to the link, checks
** that there are the correct number of arguments (i.e.
16), then outputs the
** passed arguments (if given the number of arguments)
to stdout ready for use
** by the PostScript generation program.
*/
{
get_link_initdata(argc, argv);
if (strcasecmp (datum,"RAW") == 0) {
safe_free(datum);
datum = strsave("AGD66");
safe_free(projection);
projection = strsave("TMAMG54");
}
80
Dynamic Links Program Interface
safe_free(coordtype);
coordtype = strsave("EN");
#ifdef ERMINIT_NOTRAW
#else
rotation = 0; /* Sets rotation to 0 for RAW case */
#endif
safe_free(units);
units = strsave("METERS");/*
** Always assume units for coordinate
** space are meters.
*/
put_link_initdata();
exit(0);
/* NOT REACHED */
}
#define CORRECT_NR_ARGS 16
static void get_link_initdata(argc, argv)
int argc;
char **argv;
/*
** This function checks that the correct number of
arguments have been
** passed to the initialisation program, strips quotes
from any argu** ment that has them, then saves each argument into a
variable with
** a meaningful name.
*/
{
INT32 i;
char *p_c;
STRING base_progname;
progname = argv[0];
/* Check link was passed correct number of arguments
*/
if (argc != CORRECT_NR_ARGS) {
error("Wrong number of arguments, expected %d,
received %d.",
CORRECT_NR_ARGS, argc);
/* NOT REACHED */
}
/* Strip quotes off any arg that has them */
for (i = 0; i < argc; i++) {
Dynamic Links Program Interface
81
p_c = argv[i];
if (*p_c == '"') {
argv[i] = ++p_c;
while (*p_c != '\0' && *p_c != '"') {
p_c++;
}
*p_c = '\0';
}
}
/* Save passed arguments into variables with
meaningful names */
command = strsave(argv[1]);
datum = strsave(argv[2]);
projection = strsave(argv[3]);
coordtype = strsave(argv[4]);
units = strsave(argv[5]);
rotation = atof(argv[6]);
tlx = atof(argv[7]);
tly = atof(argv[8]);
brx = atof(argv[9]);
bry = atof(argv[10]);
canvas_width = atof(argv[11]);
canvas_height = atof(argv[12]);
dpi_x = atof(argv[13]);
dpi_y = atof(argv[14]);
filespec = strsave(argv[15]);
}
static void put_link_initdata(void)
/*
** This function outputs the (validated) arguments
passed to the link
** to standard output ready for processing by the
PostScript generation
** program.
*/
{
output_string(command);
output_string(datum);
output_string(projection);
output_string(coordtype);
output_string(units);
output_double(rotation);
output_double(tlx);
output_double(tly);
output_double(brx);
output_double(bry);
output_double(dpi_x);
output_double(dpi_y);
82
Dynamic Links Program Interface
output_string("MULTI");
#ifdef DEBUG
fprintf(tfp2, "\n");
fclose(tfp2);
#endif
}
/* *
*/
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
static void output_string(s)
STRING s;
/*
** This function outputs a string argument in the
correct format for use
** by the PostScript generation program.
*/
{
fprintf(stdout,"\"%s\" ", s);
#ifdef DEBUG
fprintf(tfp2,"<%s>",s);
#endif
}
static void output_double(d)
double d;
/*
** This function outputs a double-precision floating
point argument in the
** correct format for use by the PostScript generation
program.
*/
{
fprintf(stdout,"%.17G ", d);
#ifdef DEBUG
fprintf(tfp2,"%.17G ", d);
#endif
}
/* *
*/
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
/* VARARGS */
static void error(char *format, ...)
/*
** Simple function to output error messages encountered
when initialising
** link.
*/
Dynamic Links Program Interface
83
{
va_list args;
fprintf(stderr, "%s: ", progname);
va_start(args, format);
vfprintf(stderr, format, args);
va_end(args);
exit(1);
}
Displaying the data
The “Example” below, which illustrates scaling of EN coordinates to
pixel values, is based on this PostScript generation program. Where
that example only draws one circle, at a specified point the program
below reads a table of data.
PostScript generation program
ERMAPPER\bin\win32\ermps_table_circle
/*****************************************************
**************************
** PURPOSE:This is a sample dynamic link PostScript
generation program for
** drawing circles defined by data read from a simple
ASCII data file.
**
** The program reads an ASCII file containing data of
the form:
**
**
x, y, r, <text>
**
** and generates PostScript output for displaying
circles of radius r at the
** location (x,y) in an ER Mapper image window.
**
** NOTES:
**
- Coordinates are assumed to be in meters.
**
******************************************************
************************/
#ifndef lint
static char *sccsident="@(#)%M%:%I%%D%Copyright Earth
Resource Mapping 1989-98";
#endif
#include "ERS.h"
#include "ps_util.h"
#include <stdio.h>
84
Dynamic Links Program Interface
void main(int argc,char **argv)
/*
** Main program for dynamic link PostScript generation
program.
*/
{
erm_dlinkargs dlink;
FILE *fd;
char line_buf[BUFSIZ];
int circles = TRUE;
#if !defined(win32)
char str[255];
#endif
/* Used to determine whether to generate filled
circles or not */
if(strcasecmp(argv[0], "ermps_table_outline") == 0)
circles = FALSE;
else
circles = TRUE;
/*
** Save the arguments passed by ER Mapper into the
"dlink"
** structure ready for processing.
*/
if(!erm_initdlinkargs(argc,argv,&dlink))
exit(0);
if(dlink.filespec == NULL || *dlink.filespec ==
'\0'){
fprintf(stdout,"Filespec is null \n");
exit(0);
}
/* Open the file passed from the initialisation
program as last argument */
if((fd = fopen(dlink.filespec,"r")) == NULL){
fprintf(stdout,"Could not open table:
%s\n",dlink.filespec);
#if !defined win32
fprintf(stdout,"System Error : %d
%s\n",erm_errno(),
#ifdef sun4
sys_errlist(erm_errno()));
#else
Dynamic Links Program Interface
85
strerror(erm_errno()));
#endif
#endif
exit(0);
}
/*
** Write out the required PostScript definitions
*/
/* Write out PostScript header */
fprintf(stdout,
"%%!PS-Adobe-1.0\n"
"%% Table Circle dynamic link for table file
$FILESPEC\n"
"%% Args: $*\n"
"%%\n");
fflush(stdout);
if (!strcmp(dlink.projection, "GEODETIC"))
{
fprintf(stdout,
"/x_map {\n"
"dup %lf gt\n"
"{ 360.0 sub }\n"
"{ dup %lf lt\n"
"{ 360.0 add } if\n"
"}\n"
"ifelse\n"
"%lf sub\n"
"} def\n",
dlink.brx,
dlink.tlx,
dlink.tlx
);
}
else
fprintf(stdout, "/x_map { %lf sub }
def\n",dlink.tlx);
#
86
fprintf(stdout,
"/x_scale { %d %lf %lf sub div } def\n"
"/y_scale { %d %lf %lf sub div } def\n",
dlink.canvaswidth,
dlink.brx,
dlink.tlx,
Dynamic Links Program Interface
dlink.canvasheight,
dlink.tly,
dlink.bry
);
/* Write out PostScript definition for circle
outline. */
fprintf(stdout,
"/do_outline {%% e n value\n"
"gsave\n"
"3 1 roll%% get Northing (Y)\n"
"%lf sub \n"
"y_scale mul\n"
"exch %% get Easting (X)\n"
"x_map\n"
"x_scale mul\n"
"exch\n"
"translate\n"
"gsave\n"
"1 from72pt setlinewidth\n"
"-5 from72pt 0 moveto\n"
" 5 from72pt 0 lineto\n"
" 0 from72pt -5 from72pt moveto\n"
" 0 5 from72pt lineto\n"
"stroke\n"
"grestore\n"
"newpath\n"
"%lf mul 2 div\n"
"0 exch 0 exch\n"
"2 from72pt setlinewidth\n"
"0 360 arc stroke\n"
"grestore\n"
"} def\n",
dlink.bry,
dlink.dpix
);
/* Write out PostScript definition for drawing
filled circle. */
fprintf(stdout,
"/do_circle {%% e n value\n"
"gsave\n"
"3 1 roll%% get Northing (Y)\n"
"%lf sub \n"
"y_scale mul\n"
"exch %% get Easting (X)\n"
"x_map\n"
"x_scale mul\n"
"exch \n"
"translate\n"
Dynamic Links Program Interface
87
"newpath\n"
"%lf mul 2 div\n"
"0 exch /cradius exch def 0 exch cradius \n"
"0 360 arc \n"
"%%0.5 setgray fill\n"
"0.0 setgray eoclip\n"
"0.5 setlinewidth\n"
"/l_length cradius cradius mul 2 mul sqrt cvi
2 mul def\n"
"cradius neg cradius neg translate\n"
"/X 0 def\n"
"/Y cradius 2 mul def\n"
"cradius 2 mul cvi {\n"
"X Y moveto\n"
"l_length l_length rlineto\n"
"stroke\n"
"/Y Y 2 sub def\n"
"} repeat\n"
"grestore\n"
"} def\n"
"%%\n",
dlink.bry,
dlink.dpix
);
/*
** Now read the data from input and generate the
output PostScript file
** for specifying which objects to draw.
*/
while(!feof(fd) && fgets(line_buf,BUFSIZ,fd) !=
NULL){
if(line_buf[0] && line_buf[0] != '#' &&
line_buf[0] != '\n')
{
double x, y, size;
sscanf(line_buf,"%lf%lf%lf,",&x,&y,&size);
/*
** If code called as ermps_table_circle then
filled
** circles are drawn.
*/
if (circles)
fprintf(stdout, "%lf %lf %lf do_circle\n",
x, y, size);
else
fprintf(stdout, "%lf %lf %lf do_outline\n",
x, y, size);
}
88
Dynamic Links Program Interface
}
fclose(fd);
fprintf(stdout, "%s", "%% end of postscript\n");
fflush(stdout);
exit(0);
}
Example 3 - Dynamic Link
to ARC/INFO
This link accesses ARC/INFO and extracts a cover. It passes
ARC/INFO the page size and image extents and ARC/INFO generates
PostScript for the appropriate area, scaled to the requested page
size. Linking to a system that generates PostScript output is ideal
because very little work has to be done by the link itself, only
accessing the system and converting the PostScript to ER Mapper
format. This Dynamic Link simply extracts a plot file but could easily
be edited to use more complex ARC/INFO and ARC/PLOT processing.
Dynamic link menu entry $ERMAPPER/config/dynamiclinks.erm
1. Menu option
"Dynamic Link to
ARC/INFO"
3. PostScript
generation
program call
"ermps_ar
c"
4. PostScript 5. Link chooser
type
(optional)
MONOCO
LOUR
"erm_arc_la
yer"
6. Initialization
program call
(optional)
7. Edit flag
(optional)
"erminit_
en0"
Choosing a Layer
The link chooser program changes to the directory holding ARC/INFO
covers, finds the list of covers and sends them to STDOUT to be
picked up and displayed by the standard link chooser.
Link chooser program $ERMBIN/erm_arc_layer
#!/bin/sh
#
# Returns all ARC/INFO covers in the workspace
#
# This must return a list of the layers available to the
user.
#
# In ARC/INFO terms, a layer is a "cover" within a
workspace, so we
# simply return all the covers within the workspace that
is accessible
# by ER Mapper (via the ARC_WORKSPACE value in the
site.erm configuration file).
#
# If the value ARC_REMOTE is defined in site.erm, then
it is assumed that
Dynamic Links Program Interface
89
# ARC/INFO is running on a remote machine, and
ARC_REMOTE is used to log onto
# that machine (typically a rsh command) and
ARC_REMOTE_ARC will run the
# remote arc info.
#
# In both local and remote cases it assumed that
ARC/INFO is running on a
# Unix system. This shell script needs to be changed if
it is not.
# gets the workspace name from the site.erm file
ARC_WS=‘$ERMBIN/erm_menu/erm_qsite ARC_WORKSPACE‘
if [ $? -ne 0 ]
then
echo "The ARC/INFO Workspace to use must be defined
in site.erm" 1>&2
# generates error message if workspace name is not
found
exit 1
fi
# changes workspace name to lowercase
ARC_WS=‘echo $ARC_WS | tr "[A-Z]" "[a-z]"‘
# gets the remote host name from the site.erm file
ARC_REMOTE=‘$ERMBIN/erm_menu/erm_qsite ARC_REMOTE‘
if [ $? -eq 0 ]
then
# runs this if a remote host is found
# remote machine is assumed to be a Unix system
# we don’t use the LISTCOVERAGES because of the
header stuff it hands back,
# so find is used instead.
###
$ARC_REMOTE $ARC_ARC LISTCOVERAGES $ARC_WS
NOSTATUS
### DO NOT USE
# accesses the remote host, changes directory, finds the
list of
# covers and sends it to stdout in uppercase
rsh $ARC_REMOTE "cd $ARC_WS; find . -name ’*’ -prune
-print" \ |
awk -F\/ ’{ print $2 }’ | \
tr "[a-z]" "[A-Z]"
else
# else if remote host name is not found the local
version of the
# previous command is executed
cd $ARC_WS; find . -name ’*’ -prune -print | \
awk -F\/ ’{ print $2 }’ | \
tr "[a-z]" "[A-Z]"
###
$ARC_ARC LISTCOVERAGES $ARC_WS NOSTATUS
### DO NOT USE
90
Dynamic Links Program Interface
Initializing
The link initialization program is the same as in the previous example
and will not be repeated here. It could be improved to query
ARC/INFO for the data extents.
Generating output
The PostScript generation program asks for PostScript output from
ARC/INFO and displays the results.
PostScript generation program $ERMBIN/ermps_arc
#!/bin/sh
# start of shell script
#
# Returns a ARC/INFO cover in PostScript
#
# In ARC/INFO terms, a layer is a "cover" within a
workspace, so we
# run arcplot to generate a PostScript plot for the
region and cover selected.
#
# The following must be defined in site.erm:
#
# ARC_WORKSPACE - the ARC/INFO workspace to use
# ARC_ARC
- the ARC/INFO arc command
# ARC_REMOTE
- (optional) the remote machine ARC/INFO
is running on
#
# In both local and remote cases it assumed that
ARC/INFO is running on a
# Unix system. This shell script needs to be changed if
it is not.
#
# Arguments (see ER Mapper manuals for full details):
# 1
2
3
4
5
6
7
8
9 10
11
12
13
14
15
# cmd datum proj’n coord units rotation tlx tly brx bry
canvasw canvash dpiX dpiY file
#
# checks for 15 arguments
if [ $# -ne 15 ]
then
echo "$0: Expected 15 Dynamic Link arguments." 1>&2
exit 1
fi
# defines shell procedure output_header which cats
following postscript to stdout
output_header() {
cat <<-EOF
%!PS-Adobe-1.0
% start of postscript
% PostScript dynamic link for file $FNAME
% define procedure to convert inches to points
Dynamic Links Program Interface
91
% hide ER Mapper variable device height...
/inch {72 mul} def
% scale to fit - scale all dimensions by
pixels/points factor to convert standard
% postscript to ER Mapper postscript
WidthI $PAGE_WIDTH inch div HeightI $PAGE_HEIGHT
inch div scale
%
%
-20 -15 translate % for ARC/INFO 5 only - removes
offset
EOF
% end of postscript
}
# Grab the arguments and set them up in meaningful
variable names.
# reads arguments into variables
COMMAND=$1
# should be "postscript"
DATUM=$2
# geodetic datum name
PROJECTION=$3
# projection name
COORDTYPE=$4
# type of coordinates
(EN, LL, or RAW)
UNITS=$5
# Units (eg: METERS)
ROTATION=$6
# rotation
TLX=$7
# top left x coordinate
TLY=$8
# top left y coordinate
BRX=$9
# bottom right x coordinate
shift 9
BRY=$1
# bottom right y coordinate
CANVASWIDTH=$2
# window width (0 on init)
CANVASHEIGHT=$3
# window height (0 on init)
DPIX=$4
# x dots per inch (0 on init)
DPIY=$5
# y dots per inch (0 on init)
FILESPEC=$6
# file spec or choice string
# calculates er mapper page dimensions in inches
PAGE_WIDTH=‘echo $CANVASWIDTH $DPIX | awk ’{printf
"%f",$1/$2}’‘
PAGE_HEIGHT=‘echo $CANVASHEIGHT $DPIY | awk ’{printf
"%f",$1/$2}’‘
# sets up temporary plot and postscript files
PLOT_FILE="/tmp/ermapper$$.plt"
PS_FILE="/tmp/ermapper$$.ps"
# on both local and
remote machine
# gets the arc/info workspace from the site.erm file
ARC_WS=‘$ERMBIN/erm_menu/erm_qsite ARC_WORKSPACE‘
if [ $? -ne 0 ]
then
92
Dynamic Links Program Interface
# prints error message if workspace can’t be found
echo "The ARC/INFO Workspace to use must be defined
in site.erm" 1>&2
exit 1
fi
# changes workspace name to lower case
ARC_WS=‘echo $ARC_WS | tr "[A-Z]" "[a-z]"‘
# gets the path to ARC/INFO from the site.erm file
ARC_ARC=‘$ERMBIN/erm_menu/erm_qsite ARC_ARC‘
if [ $? -ne 0 ]
then
# prints error message if path is not found
echo "The ARC/INFO program name and path must be
defined in site.erm" 1>&2
exit 1
fi
# gets remote host from site.erm file
ARC_REMOTE=‘$ERMBIN/erm_menu/erm_qsite ARC_REMOTE‘
if [ ${ARC_REMOTE:-"LOCAL"} != "LOCAL" ]
then
# code for remote ARC/INFO system
# remote machine is assumed to be a Unix system
# pipe the following to the remote host
cat <<-EOF | rsh $ARC_REMOTE $ARC_ARC 1>&2
WORKSPACE $ARC_WS # specify workplace
ARCPLOT
# block of ARC/PLOT commands
DISPLAY 1039 1 # specify display
$PLOT_FILE
# specify name of output plot file
MAPEXTENT $TLX $BRY $BRX $TLY# specify ER Mapper
map extents
PAGESIZE $PAGE_WIDTH $PAGE_HEIGHT# specify page
size in inches
ARCS $FILESPEC # specify cover chosen by user arg 15
QUIT
POSTSCRIPT $PLOT_FILE $PS_FILE 1 #convert the
plotfile to postscript
QUIT
EOF
# end of remote commands
output_header
# write PS wrapper. set postscript
scaling.
rsh $ARC_REMOTE cat $PS_FILE
# write the
ARC/INFO PS file to stdout
rsh $ARC_REMOTE rm -f $PLOT_FILE 1>&2# delete
temporary plot file
rsh $ARC_REMOTE rm -f $PS_FILE 1>&2# and postscript
file
Dynamic Links Program Interface
93
exit 0
else
$ARC_ARC <<-EOF 1>&2
WORKSPACE $ARC_WS # the same procedure for
ARC/INFO
ARCPLOT
# running locally
DISPLAY 1039 1
$PLOT_FILE
MAPEXTENT $TLX $BRY $BRX $TLY
PAGESIZE $PAGE_WIDTH $PAGE_HEIGHT
ARCS $FILESPEC
QUIT
POSTSCRIPT $PLOT_FILE $PS_FILE 1
QUIT
EOF
rm -f $PLOT_FILE
if [ -f $PS_FILE ]
then
output_header# except that this checks if
ARC/INFO
cat $PS_FILE# succeeded in generating the
postscript files
rm -f $PS_FILE
exit 0
else
echo "ermps_arc: Unable to create the postscript
file." 1>&2
exit 1
fi
fi
exit 0
94
Dynamic Links Program Interface
PostScript
PostScript is traditionally a page layout based language, with
dimensions specified in points (where there are 72 points to the
inch). Dedicated to accurate image processing, ER Mapper is
concerned with displaying images to maximum device resolution.
The way in which ER Mapper interprets PostScript has been tailored
to support this priority. Thus, the key to expressing dimensions in
ER Mapper is the following.
Dimensions in pixels
Dimensions in PostScript code are interpreted by ER Mapper to be in
pixels or dots not points.
Thus, the PostScript command “300 250 rmoveto” means “move
300 pixels to the right and 250 pixels up”.
Variable canvas size
A second difference between page based applications and ER Mapper
is that, for ER Mapper, the canvas size depends on the current size
of the image window (or required hardcopy dimensions). For
example, a canvas rendered on a 44 x 96 by 400 dpi electrostatic
plotter would be 17600 x 38400 pixels, and a canvas for a display
window of 4 x 4 at 83 dpi would be 332 x 332 pixels.
Defined variables
To cope with these varying dimensions, ER Mapper defines four
variables for use within its PostScript. These variables are always
available in any Dynamic Link. They are:
•
WidthI - the value of argument 11, the canvas width in pixels
•
HeightI - the value of argument 12, the canvas height in pixels
•
dpiX - the value of argument 13, the x device resolution in dots
per inch
•
dpiY - the value of argument 14, the y device resolution in dots
per inch
where the arguments are those defined in the “Link
initialization” section.
PostScript
95
Example
The example below shows a portion of the code from the PostScript
generation program in “Example 1 - Example user dynamic link”
above, with the addition of “ER Mapper”.
0 0 moveto
WidthI 0 lineto
WidthI HeightI lineto
0 HeightI lineto
0 0 lineto
stroke
0 0 moveto
WidthI HeightI lineto
stroke
WidthI 0 moveto
0 HeightI lineto
stroke
/Helvetica-Bold findfont dpiX scalefont setfont
WidthI 0.1 div HeightI 0.1 div moveto
(ER Mapper) show
showpage
(WidthI,
HeightI)
PostScript code making use of
the ER Mapper defined variables
ER Mapper
(0,0)
The value of the “WidthI” and “HeightI” dimensions change with
the size of the canvas, whereas the device resolution variable
“dpiX” has been used to specify text exactly 1 inch high,
regardless of the size of the canvas.
ER Mapper PostScript
Dynamic Link generation programs must take into account
ER Mapper’s pixel coordinate system. In addition, pixel-based
PostScript files can be displayed using ER Mapper’s “Dynamic Link
coded PostScript” “Monocolor” and “Truecolor” Dynamic Links.
Standard Postsript
PostScript from other sources must be scaled from a “72 points per
inch” to a “pixels” coordinate system.
96
PostScript
For example, the following code, from ER Mapper’s “8.5x11 inch
Monocolor PostScript” Dynamic Link, scales PostScript files to fit the
image window. The files are assumed to have been created using a
standard drawing or writing package on an 8.5x11 inch page.
The variables “WidthI” and “HeightI” are the canvas width and height
passed to the Dynamic Link in parameters 11 and 12 as defined on
the previous page. For example, in the following PostScript:
/inch {72 mul} def WidthI 8.5 inch div HeightI 11.0 inch
div scale
‘WidthI 8.5 inch div’ is the x scale factor and ‘HeightI 11.0 inch div’
is the y scale factor.
If your image is composed on a different size page to 8.5 x 11
inch the overlay won’t fit the image exactly. Similar Dynamic
Links can easily be constructed to scale other sizes of PostScript
page (for example A4, or 3 inch x 5 inch) to the ER Mapper
canvas.
Variable aspect ratio
The figure below shows how this scaling squashes the image to fit in
the current window, varying the image aspect.
Dimensions in points
There are two remaining ER Mapper defined variables which may be
useful, especially if you have a printing background and are used to
working in points. These are:
from72pt converts dimensions in points to dimensions in pixels. It is
defined as:
/from72pt {dpiX 72 div mul} def
Thus, for example, you would use:
12 from72pt scalefont - to set a font to 12 points, 72 from72pt
72 from72pt rlineto - to move right 1 inch and up 1 inch.
Similarly,
fromdevpt converts dimensions in pixels to dimensions in 72 point.
It is defined as:
/fromdevpt { 72 dpiX div mul} def
PostScript
97
Summary of
ER Mapper
PostScript
functions
Specifying dimensions and position
Dimension type
Usage
examples
ABSOLUTE Dimensions
in points
•
8 from72pt setlinewidth
ABSOLUTE Dimensions
in inches
Useful for setting absolute text sizes
or line thicknesses
•
Use ER Mapper defined procedure
“from72pt”
•
Useful for specifying absolute
dimensions in inches
•
RELATIVE Dimensions in •
pixels
12 from72pt scalefont
3 dpiX mul 2 dpiY mul rlineto
dpiX 2 div setlinewidth
Use ER Mapper defined variables
“dpiX” and “dpiY”
Useful for defining position
•
Use corner coordinates, for example
the shell script “TLX”, “TLY”, “BRX”
and “BRY”, and canvas dimensions
“WidthI” and “HeightI” to scale image
coordinates to PostScript pixel
coordinates
•
Use WidthI and HeightI to specify
dimensions relative to the window
•
The dimensions specified in pixels
depend on the current device
resolution
/x E ${TLX} sub WidthI mul
${BRX} ${TLX} sub div
0.1 WidthI 0.9 HeightI moveto
0.05 HeightI setlinewidth
10 setlinewidth
Global ER Mapper defined PostScript variables
variable/procedure
name
98
Dynamic Link parameter
number/procedure definition
explanation
PostScript
WidthI
•
argument 11
canvas width in pixels
HeightI
•
argument 12
canvas height in pixels
•
argument 13
•
argument 14
•
dpiX 72 div mul
•
72 dpiX div mul
dpiX
dpiY
from72pt
fromdevpt
device resolution in dots per inch Y
Example
PostScript
device resolution in dots per inch X
scale by dpiX/72
scale by 72/dpiX
The example below is based on the “Table of Data Shown as Circles”
Dynamic Link . It only draws a single circle while the link can process
a table of eastings, northings and values. The code for the entire
Dynamic Link is given in the “Displaying the data” section above.
%!
start of PostScript
/TLX 460000 def /TLY 6200000 def
defines the top left coordinate
/BRX 460500 def /BRY 6180000 def
defines the bottom right coordinate
/N 6185000 def
defines the variable N (Northing) with
value 6185000
/E 460400 def
defines the variable E (Easting) with
value 460100
/R dpiX 2 div def
sets the radius to 1/2 inch
/x_scale {WidthI BRX TLX sub div}
def
defines x_scale = WidthI / (BRX-TLX)
/y_scale {HeightI TLY BRY sub div}
def
defines y_scale = HeightI / (TLY - BRY)
gsave
stores the current origin position
E TLX sub x_scale mul
converts the easting value to position
across the screen in terms of pixels
and leaves this on the stack
N BRY sub y_scale mul
converts the northing value to position
up the screen in terms of pixels and
adds this to the stack
translate
the point defined by the two stack
entries becomes the new origin
0 0 R 0 360 arc stroke
draws a circle centered on the new
origin
-2 -2 moveto (+) show
draws the center of the circle
99
grestore
returns to the previous origin
showpage
sends the page to the output device
(460 000E, 6 200 000N)
TLY
The global ER Mapper
PostScript variables have
been used and the following
values have been assumed:
WidthI = argument 11 = 400
HeightI = argument 12 = 400
dpiX = argument 13 = 84
dpiY = argument 14 = 84
400 x 400 pixel window
+
(460 500E, 6 180 000N)
BRY
TLX
(E - TLX) .
BRX
(WidthI)
(BRX - TLX)
The radius is set absolutely at 1/2 inch using the code “/R dpiX
2 div” where dpiX is the number of pixels in one inch for the
current device. In the same way an absolute dimension of three
inches would be specified as “3 dpiX mul” and so on.
The pixel coordinates of the target point, specified in EastingNorthing coordinates (E,N), are calculated using the EN extents
of the current window and the pixel dimensions of the window.
Performance and
accuracy
Your PostScript can have a significant impact on the performance
and accuracy of your Dynamic Link. A well constructed Dynamic Link
has high performance and high accuracy (equal to or greater than
the DPI of the output device). Remember: ER Mapper Dynamic
Links are always generated at device resolution.
Performance and accuracy will be maximized if you pay attention to
the following points.
Use device DPI
Work at device DPI where possible to ensure maximum accuracy.
Integers not reals
Use integers scaled to the device DPI. PostScript processes integers
faster than reals and there is little point in drawing at higher
resolution than the device DPI.
Reduce PostScript file
size
Use “defines” to reduce your PostScript text file size as this will
reduce the processing time. In the example below, the second
column of code is faster than the first because it has fewer characters
and uses integer rather than real values.
100
PostScript
Use Monocolour
PostScript
Use MONOCOLOR Dynamic Links instead of TRUECOLOR Dynamic
Links unless you intend your output to create multi-color overlays.
MONOCOLOR links consume less memory when running and are
faster.
Extract current data
For Dynamic Links to GIS, DBMS and other such systems, try to
extract data for only the area currently being covered by the
ER Mapper image. There is no point in extracting data outside the
image window (although there is no harm in doing so) and the less
data being processed by the link, the faster it will run.
Use ER Mapper
coordinates
Remember ER Mapper PostScript is based on device pixels, not
points. Your dimensioning commands, such as scalefont,
setlinewidth, moveto and lineto calls, need to take this into
account.
For example, consider the following two example Dynamic Links,
both of which draw vectors:
Example of slow PostScript
1 from72pt setlinewidth
0.0 0.0 moveto
100.1 200.7 lineto
300.3 400.9 lineto
100.3 400.9 lineto
200.3 400.9 lineto
300.3 400.9 lineto
stroke
Using existing
PostScript
Example of fast PostScript
/W {from72pt setlinewidth}
def
/M moveto def
/L lineto def
/S stroke
1 W
0 0 M
100 201 L
300 401 L
100 401 L
200 401 L
300 401 L
S
Many systems to which you may wish to create a Dynamic Link
support PostScript output. All that is neccessary to use this output is
to rescale it to the size of the ER Mapper image.
For example, suppose you have a system you wish to connect to
which always outputs PostScript scaled such that (0.0, 0.0) is
bottom-left and (2.0, 4.0) is top-right of the image.
To rescale this PostScript so that ER Mapper will use it, do:
WidthI 2.0 div HeightI 4.0 div scale% scale to ER
Mapper size
ervecmacro.erm
PostScript
The ‘ervecmacro.erm’ file can be found in the ‘config’ directory. It is
a file used internally by ER Mapper to convert ERVEC files into
PostScript format before output to a screen or printer. It is a Read
Only file and must not be altered.
101
102
PostScript
The ER Mapper Configuration File
(config.erm)
The configuration file provides information to ER Mapper about the
computer environment in which it is operating. For Unix installations,
the hardware configuration (display types etc.) to be used on the
network and software license information for each computer running
ER Mapper are stored in ‘config.erm’.
The various selections for each entry in the configuration file are
discussed in detail below. The example included in this chapter
contains entries for a typical multi-license site.
ERMConfig Block
The configuration data is contained in a block in a similar manner to
other ER Mapper ascii text information files. The block name
ERMConfig encloses the entries for the configuration. Individual
entries are described below.
•
Version: The version of ‘config.erm’ definition.
For example,
Version = "5.0"
•
PostScriptPrinter: The command to ouput to your PostScript
printer, if you have one. For example:
PostScriptPrinter="lpr -Ppostscript"
The shipped version of ER Mapper has:
PostScriptPrinter = "lpr"
If you have a printer, such as a HP laserjet, that can print line
output, but not PostScript, you should comment out the
PostScriptPrinter entry to stop ER Mapper from thinking it has
access to a PostScript printer.
•
LinePrinter: The command to output to your line printer, if you
have one. For example, ER Mapper is shipped with the following
line:
LinePrinter = "lpr"
•
Units: The units entry specifies the unit type for all quantities
displayed by ER Mapper. The units must be expressed in metric.
For example,
Units = Metric
•
DefaultRGBLUT: Not used.
•
DefaultHSILUT: Not used.
The ER Mapper Configuration File (config.erm)
103
•
DefaultRtShade: Not used.
•
DefaultHardcopy: The default device for printing hardcopy
images. If more than one hardcopy device is available on the
network, the default device may be a fast, low resolution printer
for rapid assessment of a scene. For example,
DefaultHardcopy = "PaintJet"
•
DefaultHistStyle: The default histogram style in the Transform
window.
There are three allowed values for the DefaultHistStyle:
•
Non-Cumulative - Histogram which is a visual representation
of the relative frequency for each discrete data value.
•
Cumulative - Histogram showing the number of data values
that are below the upper end point of each data value.
•
DeQuantised - Histogram showing the relative frequency for
a continuous set of data values. For example, data with
floating point type data values would be better displayed as
a DeQuantised histogram.
For example,
DefaultHistStyle = DeQuantised
•
EnforceAspectRatio: If the aspect ratio is enforced the pixel size
and pixel overlap information for the image files being processed
is used to produce an image in an ER Mapper window which has
the correct aspect ratio. The pixel distance in the horizontal and
vertical axis is always forced to 1:1. The following example entry
in the configuration file enforces a 1:1 aspect ratio:
EnforceAspectRatio = Yes
This option may be changed using the Edit/Preferences
command.
•
DoOptimisation: Enables operator to specify whether or not to
optimise processing for speed. Usually would be set to ‘yes’. For
example, in the configuration file the following entry would
appear:
DoOptimisation = Yes
•
104
CLibrarySwitches: Default ld switches to use when loading user
C object code into ER Mapper.
The ER Mapper Configuration File (config.erm)
Algorithm files (.alg)
Algorithms define the images and processing to use to generate a
particular output image. Because they are stored separately from
the data they can easily be edited and used with other similar
images.
You don’t need to type in a text “algorithm file" - you use
ER Mapper’s Graphical User Interface to interactively define the
processing you want and when you save the algorithm ER Mapper
creates or edits the algorithm file automatically.
Algorithm files define the data sources, filters, transformations and
formulae used to create the desired image.
The algorithm file format is subject to change.
Example
algorithm file
The following algorithm file, was created by simply clicking on the
necessary processing steps within the Algorithm window and then
saving it to disk with the file name
“examples\Applications\Land_Information\two_surface_example.al
g”. In this example, the algorithm includes two surfaces, one with a
pseudocolor layer and vector layer, and the other with a pseudocolor
and intensity layer.
Algorithm Begin
Version= "5.7"
Name = "two_surface_example"
Description= "Example algorithm with two surfaces"
Author= "ER Mapper"
Comments= "Example two surface algorithm"
ViewMode= Perspective3D
LastUpdated= Thu Sep 03 01:48:32 GMT 1998
BackGroundColourSet= No
BackGroundColour= 0,0,0
ConvertToGreyscale= No
CoordinateSpace Begin
Datum = "NAD27"
Projection= "NUTM11"
CoordinateType= EN
Rotation= 0:0:0.0
CoordinateSpace End
TopLeftCorner Begin
Eastings= 505564.9746060915
Northings= 3651045.652393905
TopLeftCorner End
BottomRightCorner Begin
Eastings= 525263.3836848846
Northings= 3631347.243315111
BottomRightCorner End
MosaicType= Overlay
PageSize Begin
Algorithm files (.alg)
105
PageConstraint= Scale
PageWidth= 8.5
PageHeight= 11
TopBorder= 0.3937007874015748
BottomBorder= 2.419067768883412
LeftBorder= 0.3937007874015748
RightBorder= 0.4094488188976378
Scale = 70502.53939080733
PageExtents Begin
TopLeftCorner Begin
Eastings= 505564.9746060919
Northings= 3651045.652393908
TopLeftCorner End
BottomRightCorner Begin
Eastings= 520786.4724096644
Northings= 3631347.243315116
BottomRightCorner End
PageExtents End
ContentExtents Begin
TopLeftCorner Begin
Eastings= 506270
Northings= 3650340.627
TopLeftCorner End
BottomRightCorner Begin
Eastings= 520053.246
Northings= 3635679.224
BottomRightCorner End
ContentExtents End
PageSize End
ThreeDInfo Begin
DrawMode= Colorfill
WindowAspectRatio= 1
ViewMatrix= {
1 0 0 0
0 1 0 0
0 0 1 0
0 0 0 1
}
ModelMatrix= {
0.96592581272130.066987276077270.24999994039540
-0.2588190138340.24999997019770.93301266431810
0 0.96592581272130.2588190138340
0 0 0 1
}
HeadMatrix= {
1 0 0 0
0 1 0 0
0 0 1 0
106
Algorithm files (.alg)
0 0 0 1
}
ScreenAxesRotn= Yes
Velocity= 0.09999999403953552
TurnRate= 9.999999747378752E-005
EyeXYZ= {
0 -250
}
Left = -47
Right = 47
Bottom= -47
Top
= 47
Near = -188
Far
= 103.4000015258789
FlyNear= 1
FlyFar= 400
FlyFOV= 45
MaterialAmbient= {
0 0 0.50196075439451
}
MaterialDiffuse= {
1 1 1 1
}
MaterialSpecular= {
0.89999991655350.89999991655350.8999999165535
1
}
MaterialShininess= 0
ThreeDInfo End
Surface Begin
Name = "Default Surface"
ZOffset= 0
Transparency= 0
ColorMode= PSEUDO
LookupTable= "pseudocolor"
Stream Begin
Type = DynamicLink
Description= "100m vector contours"
Dataset= "Muth_Valley_100m_contours.erv"
FilterProgramName= "ermps_ervec"
LinkType= TrueColour
FileExtent= ".erv $$ALG"
CanEdit= Yes
EditProgram= "erm_vec"
RGBcolour Begin
Red
= 0
Green = 0
Blue = 0
RGBcolour End
Stream End
Algorithm files (.alg)
107
Stream Begin
Type = Pseudo
Description= "100m color contours"
Dataset=
"../../Shared_Data/Digital_Terrain_Model_20m.ers"
DoStaticShade= No
SunAzimuth= 45:0:0.0
SunAngle= 45:0:0.0
StreamInput Begin
StreamInputID= 1
Kernel Begin
Type = Convolution
Directory= "filters_lowpass"
Name = "avg5"
Description= "5x5 Average filter"
Rows = 5
Columns= 5
OKOnSubsampledData= Yes
Array = {
1 1 1 1 1
1 1 1 1 1
1 1 1 1 1
1 1 1 1 1
1 1 1 1 1
}
ScaleFactor= 25
Kernel End
StreamInput End
Formula Begin
Directory= "contour"
Name = "contour_20_unit_interval"
Description= "Contour with 20 unit gap"
Formula= "CEIL( (I1-rmin(,r1,i1))/100+1)"
FormulaArg Begin
StreamInput= 1
BandNumber= 1
BandId Begin
Value = "Pseudo"
BandId End
FormulaArg End
RegionArg Begin
RegionNumber= 1
RegionName= "All"
RegionArg End
Formula End
Transform Begin
Type = Linear
MinimumInputValue= 1
MaximumInputValue= 12
MinimumOutputValue= 0
108
Algorithm files (.alg)
MaximumOutputValue= 255
LinearDef Begin
NumberOfPoints= 2
Points= {
0.0000000.000000
1.0000001.000000
}
LinearDef End
Histogram Begin
MinimumValue= 3
MaximumValue= 12
CellsBelowMin= 0
CellsAboveMax= 0
NrOfCells= 12160
Bins = {
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 15440
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
19600 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 18630 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 40070
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 7240 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 2800 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 92 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 14
}
Histogram End
DoInRealtime= No
Transform End
Stream End
Surface End
Surface Begin
Name = "Default Surface"
ZScale= 772.4866305408812
Algorithm files (.alg)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1462
0
0
0
0
0
0
214
0
0
0
0
109
ZOffset= -127.5
Transparency= 0
ColorMode= PSEUDO
LookupTable= "waterlevel"
Stream Begin
Type = Intensity
Description= "Intensity Layer"
Dataset= "Landsat_MSS_with_100m_contours.alg"
DoStaticShade= No
SunAzimuth= 45:0:0.0
SunAngle= 45:0:0.0
StreamInput Begin
StreamInputID= 1
StreamInput End
Formula Begin
Description= "Default Formula"
Formula= "INPUT1"
FormulaArg Begin
StreamInput= 1
BandNumber= 3
BandId Begin
Value = "Red"
BandId End
FormulaArg End
Formula End
Transform Begin
Type = Linear
MinimumInputValue= 0
MaximumInputValue= 255
MinimumOutputValue= 0
MaximumOutputValue= 255
LinearDef Begin
NumberOfPoints= 2
Points= {
0.0000000.000000
1.0000001.000000
}
LinearDef End
Histogram Begin
MinimumValue= 0
MaximumValue= 255
CellsBelowMin= 0
CellsAboveMax= 0
NrOfCells= 13447
Bins = {
1650 0 0 0 0 95 0 0 0
0 0 0 47 0 0 0 0 0 0
30 0 0 0 0 0 0 0 30 0
0 0 0 0 0 40 0 0 0 0
0 0 81 0 0 0 0 0 0 104
110
Algorithm files (.alg)
0 0 0 0 0 0 1910
0 0 0 2420 0 0 0
2720 0 0 0 0 0 0
0 0 0 0 0 5050 0
0 0 6230 0 0 0 0
0 0 0 0 0 0 8560
0 0 0 8700 0 0 0
0 9340 0 0 0 0 0
0 0 0 0 0 9530 0
0 0 8210 0 0 0 0
0 0 0 0 0 0 6070
0 0 0 4470 0 0 0
0 4230 0 0 0 0 0
0 0 0 0 0 3720 0
0 0 3230 0 0 0 0
0 0 0 0 0 0 2190
0 0 0 0 1650 0 0
0 1120 0 0 0 0 0
0 0 0 0 0 77 0 0
0 0 57 0 0 0 0 0
0 0 0 0 0 175
0 0
0 0
3590
0 0
0 779
0 0
0 0
10030
0 0
0 697
0 0
0 0
3430
0 0
0 285
0 0
0 0
99 0
0 0
0 46
}
Histogram End
DoInRealtime= No
Transform End
Stream End
Stream Begin
Type = Pseudo
Description= "Pseudo Layer"
Dataset= "Landsat_MSS_with_100m_contours.alg"
DoStaticShade= No
SunAzimuth= 45:0:0.0
SunAngle= 45:0:0.0
StreamInput Begin
StreamInputID= 1
StreamInput End
Formula Begin
Description= "Default Formula"
Formula= "INPUT1"
FormulaArg Begin
StreamInput= 1
BandNumber= 1
BandId Begin
Value = "Blue"
BandId End
FormulaArg End
Formula End
Transform Begin
Type = Linear
MinimumInputValue= 0
Algorithm files (.alg)
111
MaximumInputValue= 255
MinimumOutputValue= 0
MaximumOutputValue= 255
LinearDef Begin
NumberOfPoints= 2
Points= {
0.0000000.000000
1.0000001.000000
}
LinearDef End
Histogram Begin
MinimumValue= 0
MaximumValue= 255
CellsBelowMin= 0
CellsAboveMax= 0
NrOfCells= 13452
Bins = {
5230 0 0 0 0 0 0 0
0 0 0 0 0 11070 0 0
0 0 0 0 0 0 0 0 0
0 0 0 18200 0 0 0 0
0 0 0 0 0 0 0 0 0
20870 0 0 0 0 0 0 0
0 0 0 0 0 0 0 17630
0 0 0 0 0 0 0 0 0
0 0 0 0 0 14090 0 0
0 0 0 0 0 0 0 0 0
0 0 11030 0 0 0 0 0
0 0 0 0 0 0 0 0 0
9360 0 0 0 0 0 0 0
0 0 0 0 0 0 0 7540
0 0 0 0 0 0 0 0 0
0 0 0 0 5730 0 0 0
0 0 0 0 0 0 0 0 0
0 0 3860 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 2100 0
0 0 0 0 0 0 0 0 0
0 0 0 0 1740 0 0 0
0 0 0 0 0 0 0 0 0
0 1160 0 0 0 0 0 0
0 0 0 0 0 213
}
Histogram End
DoInRealtime= No
Transform End
Stream End
Surface End
Algorithm End
112
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
278
0
0
0
0
0
0
Algorithm files (.alg)
See the algorithms in the subdirectories within the ‘examples’
directory for other examples.
The supplied algorithms are listed in the Supplied Algorithms
chapter in the ER Mapper Applications manual.
Algorithm file
entries
The entries in the Algorithm file are listed below. They consist of
some overall settings followed by blocks defining the processing.
•
Version: The version number the algorithm was last saved in.
This should agree with the release of ER Mapper software you are
currently using.
Version = "6.0"
•
Name: Only used internally by ER Mapper.
•
Description: A short description of the Algorithm to be displayed
in the layer in the Algorithm dialog. This can be edited in the
Algorithm window. For example,
Description = "Example algorithm with two surfaces"
•
Author: The person who created the algorithm. For reference
only - not currently used. For example,
Author = "ER Mapper"
•
Comments: A description of the algorithm. It can contain multiple
lines of text. This field can be viewed when loading an algorithm
by pressing the Comments button.
•
PageViewMode: Describes the current algorithm Page View Mode
setting. If the algorithm has Page setup parameters set you can
specify whether the image is to be displayed on its own (normal)
or as part of the page layout (layout). If omitted, this entry
defaults to normal. This is only applicable to 2D. Allowable
PageViewMode values are:
•
normal
•
layout
For example,
PageViewMode = layout
•
Algorithm files (.alg)
ViewMode: Describes the current algorithm View Mode setting.
Allowable ViewMode values are:
113
•
Planimetric2D
•
Perspective3D
•
Flythrough
For example,
ViewMode = Planimetric2D
•
LastUpdated: Date the algorithm was last written to disk. For
example,
LastUpdated = Mon Aug 31 07:25:15 GMT 1998
•
BackGroundColourSet: Indicates whether the background color is
set in the algorithm. Allowable values are "Yes" and "No". For
example,
BackGroundColorSet = No
•
BackGroundColor: The Red,Green,Blue values specified in the
algorithm. For example,
BackGroundColor = 0,0,0
•
ConvertToGreyscale: Indicates whether the background color is
converted to greyscale. Allowable values are "Yes" and "No". For
example,
ConvertToGreyscale = No
•
CoordinateSpace Block: Defines the coordinate space of the
algorithm. See “Coordinate Space block” below.
•
TopLeftCorner Block, BottomRightCorner Block: The coordinates
of the top left corner of the algorithm extents. See
“TopLeftCorner and BottomRightCorner blocks” below.
•
SuperSampling: Indicates whether or not smoothing is desired.
This is set using the Smoothing checkbox in the Algorithm dialog.
Possible values are:
•
Bilinear - Smoothing is selected
•
NearestNeighbour - Smoothing is not selected
For example,
SuperSampling = Bilinear
•
114
MosaicType: In algorithms with different images loaded into
streams of the same type, MosaicType specifies how the edge
where the images overlap should appear. Can be either:
Algorithm files (.alg)
•
Overlay - where an image overlaps another the top one
is shown
•
Feather - where an image overlaps another values are
interpolated across the overlap to give a smooth join.
For example,
MosaicType = Overlay
Coordinate space
block
•
PageSize Block: Defines the page layout parameters for the
algorithm. See “PageSize block” below.
•
ThreeDInfo Block: Defines the 3D viewing characteristics of the
algorithm including images and processing. See “ThreeDInfo
block” below.
•
Surface Block: Defines the characteristics of the algorithm
surface, including images and processing. There is one block for
each surface on the algorithm. See “Surface blocks” below.
This describes the coordinate space that all image datasets in the
algorithm must be compatible with. This is maintained automatically.
If there is only one image in an algorithm and the user changes it to
an image with a different coordinate space, the algorithm coordinate
space will be changed.
CoordinateSpace Begin
Datum = "AGD66"
Projection = "TMAMG54"
CoordinateType = EN
Units = "METERS"
Rotation = 0:0:0.0
CoordinateSpace End
The Units entry does not apply to the cell-sizes shown in
theCellInfo block.
The information within the CoordinateSpace block is read from the
‘.ers’ dataset header and contains the following entry lines.
•
Datum: Defines the geodetic datum of the map projection.
Allowable types are RAW or any of the datums supported by ER
Mapper.
For example,
Datum = AGD66
Algorithm files (.alg)
115
•
Projection: Defines the map projection; Allowable values are
RAW or one of the map projection supported by ER Mapper.
For example,
Projection = TMAMG54
•
CoordinateType: The CoordinateType defines how the
coordinates are expressed. Allowable values are:
•
RAW,
•
LL and
•
EN.
For example,
CoordinateType = EN
•
Units: (Optional). Specifies the units of length. The most
•
Rotation: Defines the rotation of the image from true North. For
example,
common units are “METERS” and “natural”. If the units are not
specified, they default to “METERS” for RAW images and
“natural” for non-RAW images.
Rotation = 0:0:0.0
TopLeftCorner
and
BottomRightCorn
er Blocks
These are the coordinates of the top left and bottom right corners of
the image expressed in the coordinates defined by the coordinate
space. In this case the top left corner represents cell (0,0) of the
“Newcastle” image. The coordinates are expressed in the
CoordinateType specified in the CoordinateSpace Block (above).
In this case, in Eastings/Northings.
TopLeftCorner Begin
Eastings = 775700
Northings = 7997200
TopLeftCorner End
BottomRightCorner Begin
Eastings = 827300
Northings = 7930000
BottomRightCorner End
PageSize Block
116
Page size block stores information about the preferred page size,
border widths and image extents.
Algorithm files (.alg)
For example,
PageSize Begin
PageConstraint= Scale
PageWidth = 8.5
PageHeight = 11
TopBorder = 0.3937007874015748
BottomBorder = 2.419067768883412
LeftBorder = 0.3937007874015748
RightBorder = 0.4094488188976378
Scale = 70502.53939080733
PageExtents Begin
TopLeftCorner Begin
Eastings = 505564.9746060919
Northings = 3651045.652393908
TopLeftCorner End
BottomRightCorner Begin
Eastings = 520786.4724096644
Northings = 3631347.243315116
BottomRightCorner End
PageExtents End
ContentExtents Begin
TopLeftCorner Begin
Eastings = 506270
Northings = 3650340.627
TopLeftCorner End
BottomRightCorner Begin
Eastings = 520053.246
Northings = 3635679.224
BottomRightCorner End
ContentExtents End
PageSize End
•
PageConstraint: The type of page constraint for the algorithm.
Allowable values are:
•
None - the page contents are set by the current image
window zoom
•
Page - the page size varies automatically
•
Border - the border varies automatically
•
Scale - the scale varies automatically
For example,
PageConstraint
•
Algorithm files (.alg)
= Scale
PageWidth: The width of the page in inches. For example,
117
PageWidth
•
PageHeight: The height of the page in inches. For example,
PageHeight
•
LeftBorder, RightBorder: The size of the left and right borders in
= 0
= 0
Scale: The scale of the image compared to ground units. For
example,
Scale
ThreeDInfo block
= 0.3937007874015748
= 2.419067768883412
inches. For example,
LeftBorder
RightBorder
•
= 11
TopBorder, BottomBorder: The size of the top and bottom
borders in inches. For example,
TopBorder
BottomBorder
•
= 8.5
= 4182.491894396
•
PageExtents Sub-Block: The coordinates of the top left and
bottom right corners of the complete page. Specified in the same
way as the “TopLeftCorner and BottomRightCorner blocks”
above.
•
ContentExtents Sub-Block: The coordinates of the top left and
bottom right corners of the image area on the page. Specified in
the same way as the “TopLeftCorner and BottomRightCorner
blocks” above.
The ThreeDinfo block contains the three dimensional viewing
parameters of the algorithm.
•
DrawMode: Sets the 3D mode in which the image is displayed.
Allowable values are:
•
WireframeHV
•
Colorfill
•
Textured
•
Auto
For example:
DrawMode = Colorfill
118
Algorithm files (.alg)
•
WindowAspectRatio: Sets the aspect ratio of the image window
•
ViewMatrix, ModelMatrix, HeadMatrix: These matrixes set the
position of the 3D image. ModelMatrix is used for 3D perspective
and ViewMatrix and HeadMatrix are used for 3D flythrough.
when viewing the image in 3D. A square window has an aspect
ratio of 1.
The following example shows the matrixes when viewing the
image from the top.
ViewMatrix= {
1
0
0
0
1 0 0
0
0 1
0
0
0 0 1
}
ModelMatrix= {
1
0
0
0
1 0 0
0
0 1
0
0
0 0 1
}
HeadMatrix= {
1
0
1 0 0
0
0 1
0
0
0 0 1
0
0
0
0
0
}
•
DisplayBBox: If set to Yes, it draws a box around the image. If
this entry is omitted, it defaults to No. For example:
DisplayBBox = Yes
•
AllLightsOff: Disables artificial lighting for 3D viewing if set to
Yes. If this entry is omitted, it defaults to No. For example:
AllLightsOff = Yes
•
ScreenAxesRotn: If set to Yes, indicates that the image can be
•
Velocity, TurnRate: These indicate the speed of movement in 3D
•
EyeXYZ: Sets the coordinates of the position from which the
rotated on the screen. ER mapper will automatically change this
to Yes if you view the image in 3D.
Flythrough.
image is viewed in 3D. For example:
EyeXYZ = {
0 -25 0
}
Algorithm files (.alg)
119
•
Left, Right, Bottom, Top, Near, Far: Sets the extents of the 3D
image. For Example:
Left = -47
Right = 47
Bottom = -47
Top = 47
Near = -188
Far = 103.4000015258789
•
FlyNear, FlyFar, FlyFOV: Sets the position and field of view of the
image when viewed in 3D Flythrough. For example:
FlyNear = 1
FlyFar = 400
FlyFOV = 45
•
MaterialAmbient: Sets the color of the overall lighting
illuminating the image in 3D. For example:
MaterialAmbient = {
0.5 0.5 0.5
}
•
MaterialDiffuse: Sets the color of the lights directly illuminating
the image in 3D. For example:
MaterialDiffuse = {
1 1 1
1
}
•
MaterialSpecular: Sets the color of the highlights of the image in
3D. For example:
MaterialSpecular= {
0.8999999761581 0.89999997615810.89999997615811
}
•
MaterialShininess: Sets the amount of shine in the 3D image.
This ranges from 0 for no shininess to 100 for full shininess. For
example:
MaterialShininess = 50
Surface Blocks
Each surface in the algorithm is represented by Surface Block.
•
Name: The name of the surface as it appears on the algorithm
dialog. This defaults to “Default Surface” if it is not specified. For
example:
Name = "Surface 1"
120
Algorithm files (.alg)
•
ZScale: Sets the height exaggeration as a percentage of the x
and y measurements of the surface; i.e a setting of 100 will draw
the height to the correct scale. For example:
ZScale = 772.5
•
ZOffset: Sets the vertical position of the surface in relation to an
arbitrary zero base point in the same units as the x and y units.
For example:
ZOffset = -127.5
•
Transparency: Sets the viewing transparency of the surface as a
percentage. A value of 0 represents no transparency and 100
represents full transparency. For example:
Transparency = 10
•
ColorMode: Describes the surface color mode. Allowable
ColorMode values are:
•
RGB
•
HSI
•
PSEUDO
•
RTSHADE
•
DATASET - Used for write to image only
For example,
ColorMode = PSEUDO
•
LookupTable: Defines the default color lookup table for the
surface. When the algorithm is loaded, the lookup table for this
surface will be set to this lookup table automatically. For
example,
LookupTable = "pseudocolor"
See the “Look up table files (.lut)” chapter of this manual for
the format of color look up table files.
•
Stream Blocks
Stream Block: Defines the layers in the surface including images
and processing. See “Stream blocks” below.
Stream blocks define the layer information within the surface. There
is one stream block for each layer.
All types of layer have the following entries.
Algorithm files (.alg)
121
•
Type: The type of layer. Allowable values are:
•
Red
•
Green
•
Blue
•
Hue
•
Saturation
•
Intensity
•
Pseudo
•
DynamicLink
•
Classification
•
Height
For example,
Type = Pseudo
•
Description: The layer description as entered in its label in the
•
Dataset: The directory and filename of the image dataset from
which the data is originating for the layer. The directory path is
relative to the algorithm directory.
Algorithm dialog box.
Dataset=
"../../Shared_Data/Digital_Terrain_Model_20m.ers"
Raster layers also have the following parameters and subblocks. The parameters for dynamic link layers are described in
“Dynamic link overlay entries” at the end of this chapter.
122
•
DoStaticShade: This is set to No if static shading is disabled.
•
SunAzimuth and SunAngle: The azimuth and angle used for
static shading layers. This would also be used when output is a
real time shade overlay to a hardcopy device or to an image. This
is adjusted either through the static or realtime shade sun angle
selector.
•
StreamInput Sub-blocks: Defines ...See “StreamInput sub-
•
Formula Sub-blocks: See “Formula sub-blocks” below.
blocks” below.
Algorithm files (.alg)
•
StreamInput SubBlocks
Transform Sub-blocks: See “Transform sub-blocks” below.
In general, each stream input corresponds to a band from an image,
along with optional input filters and transforms. In the example at
the beginning of this chapter the Intensity layer has one stream
input:
StreamInput Begin
StreamInputID= 1
Kernel Begin
.....
Kernel End
StreamInput End
•
StreamInputID: The identifier for the input. In the formula
“INPUT1” will refer to:
StreamInputID = 1
•
Kernel Sub-Blocks
Kernel Blocks: The Kernel Block defines a filter for the band.
Kernel sub-blocks may occur within the StreamInput block.
Kernel blocks may also be stored as separate ascii files. The
information contained in a kernel file is copied into the algorithm file
when a filter (kernel) is selected.
See the “Filter files (.ker) chapter in this manual for more
information.
Formula SubBlocks
Formula blocks contain the formula definition for the overlay.
Formula blocks are made up of the following elements:
•
Name: The Name is displayed in the formula window and
available for editing.
•
Description: Formula description displayed in the formula
window and available for editing. For example,
Description = "Default Formula"
•
Algorithm files (.alg)
Formula: The actual formula entry. The formula is within double
quotes.
123
Syntax for formulae is described in the Formula syntax chapter
in the ER Mapper User Guide.
For example, the default formula is:
Formula = "I1"
•
FormulaArg Blocks: FormulaArg blocks define the band that is
associated with each formula input. For example:
FormulaArg Begin
StreamInput= 1
BandNumber= 1
BandId Begin
Value = "magnetics"
BandId End
FormulaArg End
There will be as many FormulaArg blocks as there are inputs for the
formula.
See also “Formula files (.frm)” in this manual for more
information.
Transform SubBlocks
Transform blocks occur before the Formula block and/or after the
Formula block. In the example presented at the beginning of this
chapter, there is one Transform blocks after the formula in both the
intensity overlay and the pseudocolor overlay.
Transform blocks contain the following elements:
•
Type: The type of transform for the transform block. Allowable
types are:
•
Linear
•
Exponential
•
Logarithmic
•
Histogram Only
For example,
Type = Linear
Type = Logarithmic
124
•
MinimumInputValue: The minimum value of the data.
•
MaximumInputValue: The maximum value of the data.
Algorithm files (.alg)
•
•
•
MinimumOutputValue: The minimum value of the transformed
(output) data.
MaximumOutputValue: The maximum value of the transformed
(output) data.
Transform Point Coordinate Block: The name of the transform
point coordinate block depends on the type of transform. For
example, for a transform of Type Linear, the transform point
coordinate block will be named LinearDef. In this block, the
number of coordinate points is given as well as the x and y
coordinates for each of these points. For example,
LinearDef Begin
NumberOfPoints = 2
Points = {
0.0000000.000000
1.0000001.000000
}
LinearDef End
Dynamic Link
Overlay Entries
An example dynamic link layer is shown below:
Stream Begin
Type = DynamicLink
DatasetDirectory = "Shared_Data"
Dataset = "Newcastle_structure.erv"
MenuButtonDescription = "Annotation overlay"
FilterProgramName = "ermps_ervec"
LinkType = Monocolour
FileExtent = ".erv"
InitialisationProgram = "erminit_ers"
CanEdit = Yes
EditProgram = "erm_vec"
RGBcolour Begin
Red = 65535
Green = 0
Blue = 0
RGBcolour End
Stream End
The Type, DatasetDirectory and Dataset entries are the same as
for a raster stream. In addition to these, Dynamic Link streams have
the following entries.
•
Algorithm files (.alg)
MenuButtonDescription: The text displayed on the menu button.
125
•
FilterProgramName: The name of the translation program to run
•
LinkType: The type of PostScript. This can be either “Monocolour”
or “Truecolour”.
•
FileExtent: This field determines where ER Mapper will look for
the files to be linked to. It may contain a file extension, fixed
parameter or program name. This field can be omitted if ER
Mapper doesn’t need any information about where to find the
link.
•
InitialisationProgram: The program which passes information
about the coordinate space and extents of data to and from the
link. If this field is absent, ER Mapper assumes that data coming
from the link is valid in any coordinate space.
•
CanEdit: Indicates whether the data in the link can be edited. The
entry can be set “Yes" or “No”. If the entry is not present it
defaults to “No”. Currently, the only link which can be edited is
the “Annotation overlay”.
to generate the PostScript output. Usually these names begin
with “ermps_”.
Information about the Dynamic Link programming interface can
be found in “Dynamic links program interface” in this
manual.
•
RGBcolour Block: This block defines the color of the vector
overlay specified within a dynamic link or classification stream
information block. Within the RGBcolour block, there are values
for each of the Red, Green and Blue display colors. The example
below illustrates a typical entry.
The English spelling of ‘colour’ must be used in the code.)
RGBcolour Begin
Red = 65535
Green = 0
Blue = 0
RGBcolour End
126
Algorithm files (.alg)
Filter files (.ker)
Algorithm files can include filter information as described in the
“Algorithm files (.alg)” chapter. This filter information is also
stored separately as an ASCII (plain text) file. The filter file format
is described below.
Standard filters (convolutions), are stored in the subdirectories
within the ‘kernel’ directory. The ASCII filter file has the extension
‘.ker’. Following is an example of a very simple filter, a 3 by 3
averaging filter.
Kernel Begin
Name= "avg3"
Description= "3x3 Average filter"
Type = Convolution
Rows = 3
Columns= 3
OkOnSubsampledData = Yes
Array = {
1 1 1
1 1 1
1 1 1
}
Scalefactor = 9
Kernel End
The number of columns in a filter may be different from the number
of rows. However, they must both be odd numbers so that every cell
is affected by the same number of neighbours on either side, and
above and below during processing. Each element of the array may
be an integer or a floating point number.
For example,
1x3, 3x1, 3x3, 3x5, 51x37 are valid dimensions
2x2, 1x2, 4x5, 7x10 are not valid dimensions for filters.
Supplied filters are listed in the “Supplied filters” chapter of the
ER Mapper Applications manual. User defined filters may be entered
using an ascii editor, and stored in one of the subdirectories within
the ‘kernel’ directory with a ‘.ker’ extension.
The entries within the example filter file are described below.
•
Name: The name of the filter is contained within double quotes.
For example,
Name = "avg3"
•
Description: The Description entry is displayed in the Filter
window. For example,
Description = "3x3 Average filter"
Filter files (.ker)
127
•
Type: Allowable values for Type are:
•
CONVOLUTION - Normal convolution.
•
THRESHOLD - Convolution with threshold. A value is
calculated as per convolution. If the distance between the
original value and the new value is less than the threshold,
then the calculated value is used, otherwise the original value
is used.
•
USER - For filters that incorporate C Code. See the next
section.
For example,
Type = Convolution
•
Rows: The number of rows in the array. The number of rows
must be odd. For example,
Rows = 3
•
Columns: The number of columns in the array. The number of
columns must be odd.
Columns = 3
•
OkOnSubsampledData: This field determines whether a filter is
applied to the image before or after subsampling. If an overlay
contains a filter with this flag set to NO, then all processing in the
overlay will be done before subsampling.
If OkOnSubsampledData = No then the filter is applied before
subsampling takes place.
If OkOnSubsampledData = Yes then the image is subsampled
before the filter is applied. This is the default.
•
Array
1
1
1
}
Array: The table of values required to filter the data. For
example,
= {
1 1
1 1
1 1
Each element in the array may be an integer or a floating point
number.
•
Scalefactor: Scale factor for the array. Scale factor may be an
integer or floating point number.
Scalefactor = 9
128
Filter files (.ker)
C Filters
Filters of type “User” allow ER Mapper to incorporate code provided
by the user. An example is shown below. Type “User” filters have the
same Description, Rows and Columns fields as described above. The
other fields are described below.
Kernel Begin
Description = “Average”
Type = User
Rows = 3
Columns = 3
UserCodeFileName = “average"
UserFunctionName = “average”
InterfaceType = C
Kernel End
•
UserCodeFileName: The file name of a C object file or DLL
containing the compiled user code (see next section). For
example,
UserCodeFileName = "average"
refer to the file
$ERMAPPER\usercode\filter\c\average.c
•
UserFunctionName: The object file may contain more than one
function. The User Function Name is the name of the specific
function within the file. For example,
UserFunctionName = "average"
•
InterfaceType: The language in which the code is written.
Allowable value is:
•
C
For example,
InterfaceType = C
See the “C filters and functions” chapter for more information
about C Filters.
Filter files (.ker)
129
130
Filter files (.ker)
Formula files (.frm)
Formulae are stored in the subdirectories within the ‘formula’
directory. The ASCII formula file has the extension ‘.frm’. Following
is an example of a very simple difference formula.
Formula Begin
Name = “difference”
Description = “I1 - I2”
Formula = “I1 - I2”
FormulaArg Begin
StreamInput = 1
BandNumber = 4
BandId Begin
Value = “10.8”
Width = 1
Units = “um”
BandId End
FormulaArg End
FormulaArg Begin
StreamInput = 2
BandNumber = 1
BandId Begin
Value = “0.63”
Width = 0.1
Units = “um”
BandId End
FormulaArg End
Formula End
•
Name: Name of the formula, as shown in the Formula dialog box.
For example,
Name = “difference”
•
Description: Description entry for the formula.
•
Formula: The actual formula entry.
Syntax for the formula is described in the Editing raster layers
and Formula syntax chapters in the ER Mapper User Guide.
FormulaArg
Blocks
FormulaArg blocks define the band that is associated with each
formula stream input.
•
Formula files (.frm)
StreamInput: Usually associated with a band.
131
•
BandID Blocks
BandNumber: The band number associated with the band in the
image.
BandID blocks contain information about the individual bands. All
fields are optional.
•
Value: Value is the spectral value of the band.
•
Width: Width is the spectral width of the band. The width
•
Units: Units is the type of unit in which the value and width are
information is used in the image dataset header (‘.ers’ files)
only.
expressed.
Value and Units are joined together (separated by an underscore) to
create the band description. The band description is used for two
purposes:
•
Providing information about the band.
•
To enable ER Mapper to find the correct bands to use when
applying formula to an image other than the one for which it was
originally created. For example, the values for Landsat TM band
1 would be:
Value = “0.485”
Width = 0.07
Units = “um”
The description displayed by ER Mapper is obtained by joining the
value and units separated by a “_”: “0.485_um”
It is important to note that these fields can be used for types of data
other than wavelength. In these cases, width and units may be
unavailable or inappropriate.
For example, The values for a copper band of a geochemical image
might look like:
Value = “ppm_Cu”
The description would be “ppm_Cu”. In this case units and width as
defined for wavelength data do not make sense.
The Value field is free format and can be used to put in any
description desired. For example, if “ppm_Cu” is too brief, the Value
field could be set to “parts per million Copper”.
In the above example, the ascii formula file was generated by the
Save option on the ER Mapper Formula window. The specific formula
contains band information for a particular image, which is also
saved.
132
Formula files (.frm)
Formulae are created by way of the ER Mapper user interface, by
typing the formula into the Formula window and saving the formula.
Formula can then be applied to other algorithms, after suitable
substitution of the correct bands.
Formula files (.frm)
133
134
Formula files (.frm)
C filters and functions
Sections on the Formula and Filter buttons in the Editing raster
layers chapter of the ER Mapper User Guide, describe the standard
filters and functions supplied with ER Mapper. You can also add your
own Convolution and Threshold filters and make up complex
formulae using the supplied functions.
This chapter explains how to further expand the available filter and
function options by including your own C code. This chapter is only
relevant if you have knowledge of C programming or have access to
a programmer.
Filters/kernels
Filters are templates moved over the data to do such things as detect
and enhance edges and sharpen or smooth images.
There are many filters supplied with ER Mapper, these are
described in the ER Mapper Applications manual.
The filters supplied include averaging filters, geophysical filters, sun
angle filters, Laplacian, Sobel, sharpening and edge enhancement
filters.
You can create your own Convolution and Threshold filter in a
plain text file, following the format of filter files detailed in the
“Filter files (.ker)” chapter.
However, you can also create totally new types of filters by including
your own C code.
Writing and
compiling
usercode on PCs
This section discusses how to write and compile usercode on PC
platforms.
Limitations
•
FORTRAN Usercode is NOT supported
•
Only Microsoft Visual Studio 2005 is supported
In the following discussion we assume:
C filters and functions
•
you have already installed ER Mapper
•
ER Mapper is installed in the ‘C:\Program Files\ERDAS\ERDAS ER
Mapper 7.2’ directory.
135
Setting and referring to
Windows environment
variables
To set an environment variable:
set ERMAPPER=C:\Program Files\ERDAS\ERDAS ER Mapper 7.2
To refer to an environment variable
%ERMAPPER%
In this section we refer to the directory in which ER Mapper is
installed as:
%ERMAPPER%.
Checklist
You need the following files supplied with ER Mapper:
•
%ERMBIN%\erm_compile_usercode.exe — build usercode DLLs
•
%ERMBIN%\erm_compile_so.exe — used only for dynamic
compilation
•
%ERMBIN%\make_def_file.exe — build .def file from .o files
•
%ERMBIN%\erm_grep.exe — this is GNU grep for Win32
•
%ERMAPPER%\lib\win32\dllentry.o — dll entry point object
(MSVC)
•
%ERMAPPER%\lib\win32\source\dllentry.c — dll entry point
source
•
%ERMAPPER%\lib\win32\ermapper.lib — main ER Mapper library
%ERMBIN% is %ERMAPPER%\bin\win32
Files supplied with Win32 development kit (not from ER
Mapper):
•
dumpbin.exe — from WIN32 SDK or Microsoft Visual Studio 2005
•
nmake.exe, cl.exe and link.exe and associated libraries —
complete MSVC development kit
Make files and Windows batch scripts (.bat):
136
•
%ERMAPPER%\bin\pcscripts\erm_menu\erm_makeall.bat —
driver for usercodebuilds
•
%ERMAPPER%\usercode\MakeDll.win32 — build a DLL from c
source
•
%ERMAPPER%\usercode\kernel\c\Makefile.win32 — build C
kernel dlls
•
%ERMAPPER%\usercode\formula\Makefile.win32 — build C
formula dlls
C filters and functions
Example code
Example source code for the sections explained below can be found
in the
‘%ERMAPPER%\usercode\formula’ and
‘%ERMAPPER%\usercode\kernel\c’
directories. These contain sources that are shipped with ER Mapper
and can be used as a starting point when writing your own formulae
or kernels/filters.
Building new formula and
filters manually
ER Mapper places its usercode formula files (sources) in the
‘%ERMAPPER%\usercode\formula’ directory. If you want to add any
new formula files, these should be placed in this same directory.
The formulas are written as C source (.c) files. These have to be
converted to Dynamic Link Libraries (.dll) before ER Mapper can load
them.
You can use any other .c file in this directory as an example of how
to write a formula. Once you have written a formula file, use the
ER Mapper Utilities / File Maintenance / Filters / Recompile
changed C filters menu option to build the DLL files. Below is the
manual procedure for situations where the automatic menu option
does not work and for the user who wishes to gain a better
understanding of the procedure.
To edit formula and
kernels/filters C source
code
From the Utilities menu, select either File Maintenance /
Filters/Kernels / Edit a C Formula source file or File
Maintenance / Formula / Edit a C Filter source file depending
on whether on whether you are editing a formula or filter/kernel.
Select a file to edit from the %ERMAPPER%\usercode\formula or
%ERMAPPER%\usercode\kernel\c directory.
When you have completed the editing either save the file or use Save
as. to save it under a new name. Make sure that you save it with a
.c extension.
To write or build your
own formula manually
1. Open a DOS Prompt window.
2. Set the ERMAPPER environment variable to the directory in which
ER Mapper is installed.
set ERMAPPER=C:\Program Files\ERDAS\ERDAS ER Mapper 7.2
3. Modify the PATH environment variable to include the ER Mapper
PATH.
set PATH=%PATH%;%ERMAPPER%\bin\win32
4. Change to the formula source directory.
cd %ERMAPPER%\usercode\formula
At this stage you should have a formula file that you want to compile
in this directory. Assume the name of this file is form.c
5. Run the nmake command (from Microsoft Visual Studio 2005) to
build the DLL.
C filters and functions
137
nmake -f %ERMAPPER%\usercode\makedll.win32 DLLSRC=form
You should see an output similar to what is shown below:
Microsoft (R) Program Maintenance Utility Version 1.50 Copyright (c) Microsoft Corp
1988-94. All rights reserved.
Compiling form.c
cl -nologo -D_X86 -I”c:\Program Files\ERDAS\ERDAS ER Mapper 7.2\include”
-DWIN32
-Dwin32 /W3 /GX /Od -c form.c -Foform.o
form.c
Making DEF file
make_def_file form
Creating library form.lib and object form.exp...
At this stage a file named form.dll should be placed in the
‘%ERMAPPER%\usercode\formula\win32’ directory.
You can also achieve the same result by running the
‘erm_compile_usercode’ command. See “To compile usercode
directories (formulae, filters/kernels)” below.
To write and build your
own filter/kernel
manually
To compile usercode
directories (formulae,
filters/kernels)
The previous procedure applies to filters and kernels as well. The
only difference is the directory in which the source files are located.
•
The C sources for the filters/kernels are in
‘%ERMAPPER%\usercode\kernel\c’
•
The resulting DLL files are placed in
‘%ERMAPPER%\usercode\kernel\c\win32’
While this procedure is normally run using the menu options, it may
be necessary for test purposes to compile the usercode sources
manually. To do this:
1. Open a DOS Prompt window
2. Set the ERMAPPER environment variable by typing:
set ERMAPPER=c:\Program Files\ERDAS\ERDAS ER Mapper 7.2
3. Modify the PATH to include ER Mapper executables by typing:
set PATH=%PATH%;%ERMAPPER%\bin\win32
4. Change to the usercode directory by typing:
cd %ERMAPPER%\usercode\filters
erm_compile_usercode %ERMAPPER%\usercode\filters
138
C filters and functions
Notes
There are several menu options that manipulate usercode sources.
Here we are interested in options that build DLL files from source file.
The menu options that perform this task are:
•
Utilities/ File Maint/Formula/ Recompile changed User Formulae
•
Utilities/ File Maint/Filters/Kernels/ Recompile changed C Filters
These commands compile any new or changed sources in the
specified directories.
These three menu options operate on the following three directories
that contain ER Mapper usercode respectively:
•
%ERMAPPER%\usercode\formula
contains C formulae
•
%ERMAPPER%\usercode\kernel\c
contains C filters/kernels
Choosing any of these options runs the ER Mapper batch script
‘MakeAllUC’ (%ERMAPPER%\batch\erm_menu\MakeAllUC.erb)
passing ‘formula’, ‘kernel\c’ as a parameter.
This batch script runs
‘ERMAPPER\bin\pcscripts\erm_menu\erm_makeall.bat’ with the full
path name of the source directory as a parameter. The following
command shows the parameter passed in for compiling formulae
sources.
erm_makeall.bat %ERMAPPER%\usercode\filters
The ‘erm_makeall.bat’ file runs ‘nmake’ which is the make command
for Microsoft Visual Studio 2005. The exact command executed is:
nmake -nologo -f
%ERMAPPER%\usercode\filters\Makefile.win32
\CODEDIR=%ERMAPPER%\usercode\filters
There is a Makefile.win32 in each of the usercode directories. These
makefiles run the ‘erm_compile_usercode’ command to build the
DLLs from the sources. ‘erm_compile_usercode’ is an executable file
(.exe) located in $ERMBIN.
To manually compile
usercode
It may be necessary for test purposes to sometimes compile the
usercode sources manually. To do this:
1. Start a DOS Prompt window.
2. Set the ERMAPPER environment variable by typing:
set ERMAPPER=set ERMAPPER=C:\Program Files\ERDAS\ERDAS
ER Mapper 7.2
3. Modify the PATH to include ER Mapper executables by typing:
set PATH=%PATH%;%ERMAPPER%\bin\win32
C filters and functions
139
4. Change to the usercode directory by typing:
cd %ERMAPPER%\usercode\filters
erm_compile_usercode %ERMAPPER%\usercode\filters
erm_compile_usercode.exe
Understanding error messages
Notes on compiling
libermapper programs on
PC
•
Error Category:
UserCode / Dynamic Compilation (DC)
•
Error Messages (make_def_file.c):
•
Cannot find dumpbin.exe in PATH
•
Cannot find erm_grep.exe in PATH
•
Cannot execute: dumpbin /SYMBOLS <ofile .o|erm_gnu “SECT”
.....
•
Could not open exports file: <filename
•
Could not create DLL EXPORTS file
Using the ER Mapper C library under Microsoft Visual Studio 2005.
The following are instructions on how to set up a MSVC project to
compile and link against the ER Mapper C library.
They assume:
•
Full installation of ER Mapper 7.2 in c:\Program
Files\ERDAS\ERDAS ER Mapper 7.2 (substitute the correct
directory where necessary).
•
MSVC 4.2 or above is installed on system
1. Start Microsoft Developer Studio.
2. From the File menu select New.
3. Select Project Workspace and click OK
4. Enter a project name, for example ‘compile_test’.
5. Select a project directory, for example ‘c:\projects’.
6. From the Insert menu select Insert Files Info.
7. From Insert Files into project dialog select: ‘c:\Program
Files\ERDAS\ERDAS ER Mapper7.2\examples\
ER_MapperLib_Examples\example1.c
8. Click Close on project files dialog.
9. Select Tools from the menu and click Options then select
Directories.
140
C filters and functions
10. From Show Directories select Directories and add ‘c:\Program
Files\ERDAS\ERDAS ER Mapper 7.2\win32’ to the directory list.
11. From Show Directories for list select Include Files and Add
‘c:\Program Files\ERDAS\ERDAS ER Mapper 7.2\include’.
12. From Build select Settings... the Project Settings dialog will be
displayed.
•
Select C/C++ tab and add win32 to Preprocessor
Definitions.
Each item in this list should be comma delimited.
13. Select the Link tab from the Category list select Link and then
General.
14. From the Category list select General.
Add the following library names to the Object/Library Modules
field:
‘ermapper.lib’ ‘wsock32.lib’
15. From the Category list select Input.
16. To the Ignore Libraries field add:
libc.lib
17. Click OK.
18. From the Project menu select Build compile_test.exe.
The Project will now compile and link. To run the example, go into
the directory from a dos shell (the shipped examples require
command line options).
C filters and functions
141
Filter file format
This section describes the filter file formats to use your own C code.
User defined filter files should be stored in a subdirectory of the
‘kernel’ directory. Samples can also be found in the ‘kernel’
directory. The box below shows the format for a sample file. The
syntax for the Description, Rows and Columns is the same as for a
standard filter file as set out in the “Filter files (.ker)” chapter. The
other fields are described below.
Kernel Begin
Description= “Average”
Type = User
Rows = 3
Columns= 3
UserCodeFileName = “average”
UserFunctionName = “average”
InterfaceType = C
Kernel End
Example .ker file for a user defined filter
•
Type: Must be User.
Type
•
=User
User Code File Name: This is the file specification of an object file
containing the compiled user code (see next section). The path is
relative to the ‘usercode\filter’ directory. For example,
UserCodeFileName = "average"
refers to the file:
ERMAPPER\usercode\kernel\c\win32\average.dll
•
User Function Name: The object file may contain more than one
•
UserFunctionName = "average"
•
Interface Type: The language in which the user code is written.
Allowable values are:
function. The User Function Name is the name of the specific
function within the file. For example,
•
C
For example,
InterfaceType = C
142
C filters and functions
The filter Object
file
The object (or .dll) file that is executed by the C filter is stored in a
subdirectory of the ‘usercode\kernel’ directory. Sample object files
and their corresponding C source files have been stored in ‘c’
subdirectories as examples, as well as the ‘makefile’ used to compile
them. The file must contain a double precision function with the
name specified by the UserFunctionName in the Filter file (see
previous section). ER Mapper will pass two integers and one double
precision array into the function and return one double precision
value. Examples of C function source code are shown below.
double average (nr_rows, nr_cols, array)
int nr_rows;
int nr_cols;
double **array;
{
int r;
int c;
double total;
double nr_elements = nr_rows*nr_cols;
total = 0;
for (r = 0; r < nr_rows; r++) {
for (c = 0; c < nr_cols; c++) {
total += array[r][c];
}
}
return (total / nr_elements);
}
Example C Function Source Code (average.c)
In code written in C values in the array must not be changed
within the function. Such changes will produce unpredictable
results. Also, the array elements are not stored contiguously in
memory but instead take the form of an array of pointers to
other arrays.
Formula functions
In much the same way that users can incorporate their own code into
filters, they can also define functions for processing data within a
formula. When ER Mapper encounters a function name in a formula,
other than those provided within ER Mapper (and described in the
section on the Formula button “Formulae” in the ER Mapper User
Guide), it assumes it is a C function within an object file of the same
name.
For example, the formula:
"sum2(I1,I2)/2"
C filters and functions
143
makes use of the function ‘sum2’, which is assumed to be in a file
called ‘sum2.o’. Unidentified functions are reported when the image
is displayed. The object code for these functions is stored in the
‘usercode\formula’ directory.
The user-defined function must return a double precision value.
During execution ER Mapper passes the specified number of double
precision arguments to the function and returns one double precision
number.
C user defined function
name
Function names indicate whether the function uses a C interface and
can specify the number of arguments to be passed to the function.
Thus, the full syntax for a function name is:
name[n]
where
[n] is the number of arguments
Number of Arguments
To check for errors in the number of arguments passed to the
function, include that number in the name of the function. If a
different number of arguments is specified in the function call, an
error message will result.
Type of Arguments
Function arguments must be declared as double.
Examples
Here is an example function name:
"sum(I1, I2, I3)/3"
is a name of a function that does not check for the number of
arguments.
"sum2(I1, I2)/2"
calls a C function that requires two arguments to be passed to it.
C function format
Sample C source files and their corresponding object (or .dll) files
can be found in the ‘usercode\formula’ directory as well as the
‘makefile’ file which was used to compile them.
An examples of source code for functions is shown below.
double
double
double
{
return
}
sum2(a, b)
a;
b;
(a + b);
Example C Source Code (sum2.c)
144
C filters and functions
Initialization and
finalization
The C Code options make provision for initialization and finalization
routines to be incorporated in the function code. These are each
executed once only, before and after the main function is applied to
the dataset respectively. Such routines may be used to allocate and
deallocate memory or to open and close files.
Filters
Before calling a function, ER Mapper scans the C object file for
initialization and finalization routines. In the filter example above,
where UserFunctionName = "average’ is specified, ER Mapper
searches for ‘average_init’ and ‘average_final’ routines.
If found, the initialization routine will be called first and passed the
number of rows, ‘nr_rows’, and number of columns, ‘nr_cols’. Other
parameters are available and are described later in this section. A
simple example,
void average_init (nr_rows, nr_cols)
int nr_rows;
int nr_cols;
{ ... initialization routine code ...
return;
}
Example C initialization routine source code
Similarly, if it exists, the finalization routine will be called after the
function has been executed. No arguments are passed to the
finalization routine. For example,
void average_final ()
{ ... finalization routine code
...
return;
}
Example C final routine source code
For C initialization routines there are 3 additional arguments
available. These are a text string entered in the Filter editor Filter
function name field (user_code_params), a pointer to the current
Algorithm structure (p_a), and a pointer to the current Stream (or
overlay) structure (p_s).
This allows User code to extract useful information about the data
currently being processed. In particular, this means that user code
Filters can get the X and Y cell dimensions for the dataset that is
being processed. This is necessary for things like Geophysical filters,
and other filters that calculate derivatives such as slopes.
Firstly, when using the dataset cell size, be sure to set the Process
at Dataset Resolution flag on the Filter, so that you are ensured
that the data values that you get in the usercode are nonsubsampled data values.
C filters and functions
145
To get the dataset cell size in a C language User code
initialization function make sure that you #include “ERS.h” in
the User code C source file.
Your user code C filter initialization function looks something like
this:
#include “ERS.h”
static double global_cell_size_x;
static double global_cell_size_y;
void slope_init(nr_rows, nr_cols, user_code_params, p_a, p_s)
int nr_rows;
int nr_cols;
char *user_code_params;
Algorithm *p_a;
Stream *p_s;
{
DatasetHeader *p_dsh = p_s->p_cached_dshdr;
RasterInfo *p_ri = &(p_dsh->u.ri);
CellInfo *p_ci = &(p_ri->cellinfo);
double cell_width = p_ci->x;
double cell_height = p_ci->y;
/* We now have the cell dimensions - assign them to
** local global variables so the processing
** function can use at them:
*/
global_cell_size_x=cell_width; /*Assign to local global */
global_cell_size_y=cell_height; /*Assign to local global*/
}
Formula
In a similar manner to C filters, before calling a C function, the object
code is scanned for an initialization and finalization routine. In this
case, the initialization routine is passed the arguments that are
passed to the function itself as well as two extra. The two additional
arguments are the algorithm pointer and stream pointer described in
the section on kernels above.
Thus, a user code Formula function that is declared to have, for
example, three parameters, the initilization function is now called
with five parameters, the last two being the pointer to the current
Algorithm and the pointer to the current Stream. Constants are
passed down unchanged, data values are undefined. The finalization
routine is called with no arguments.
For example, when the formula ‘sum2 (I1,I2)’ is specified the
following are executed:
sum2_init(0,0)
146
C filters and functions
sum2(I1,I2)
sum2_final()
Alternatively, if ‘sum2(I1,5)’ is specified, the following are executed:
sum2_init(0,5)
sum2(I1, 5)
sum2_final()
Linking
Default switches
The ‘config.erm’ file specifies default libraries for linking to C code.
Thus:
CLibrarySwitches = "-lm -lc"
The object files may need to be linked with additional libraries. Then
the default switches within the config.erm file may be altered to
specify the additional libraries to be linked during execution. These
switches are the default setting for all user code linking (both filters
and formula functions).
For example:
"CLibrarySwitches = -L/home/lib -lERS -lm -lc"
specifies a user library called libERS.a stored in /home/lib as well as
the standard math and C libraries.
See “The ER Mapper configuration file” for detailed
information on the config.erm file.
Special case linking
When particular libraries are only used with specific filters or formula
functions, you can override the default switch settings by creating a
‘.link’ file of the same name as the function and stored in the same
directory as the ‘.o’ file. For example, to execute the function ‘test’
to be found in the object file ‘test.o’ which requires links to special
libraries, specify the linking switches in the file ‘test.link’. The default
switches in the ‘config.erm’ file are overridden. For example, a .link
file might contain the following:
-L/home/lib -lERS -lc
Special C Function
arguments
ER Mapper has two special functions that can only be used as
arguments of C functions. These are INPUTVECTOR and STATS.
Execution of either of these function arguments requires the
dynamic compiler to be turned on, otherwise an error message is
displayed.
See “Customizing ER Mapper” in the ER Mapper User Guide
for instructions on how to turn the dynamic compiler on and off.
C filters and functions
147
The dynamic compiler is on by default.
INPUTVECTOR
•
Syntax: function name (INPUTVECTOR(input list))
•
Examples: “USERFUNC (INPUTVECTOR(I1, I2, I3))”
“USERFUNC (INPUTVECTOR(I1..I5))”
The formula INPUTVECTOR passes the following arguments to the
user-defined function:
int nr_elements;
double input_vector [];
where ‘nr_elements’ is the number of items in the input list and the
elements of ‘INPUT_vector’ are double precision values of the input
list.
In the first example above, USERFUNC is called with ‘nr_elements’
equal to 3, and ‘vector’ containing double precision values
corresponding to I1, I2 and I3.
USERSTATS
USERSTATS is suppo9rt
by C interfaces only.
Syntax: function name (USERSTATS (dataset, region, bandlist))
Example:
“userfunc (USERSTATS(ers/Australia_DTM.ers, R1,
B1..B3))
The syntax for the dataset, region and bandlist specifications
can be found in the “Formulae” section of the ER Mapper User
Guide.
The formula USERSTATS passes a pointer to a structure containing
statistics for the specified dataset. The structure is defined by the file
‘ERSStats.h’ which is in the ‘include’ directory. A user function that
is designed to take USERSTATS as an argument must contain the
command:
#include "ERSStats.h"
The ‘ERSStats.h’ file is shown in the box below. Any of the statistics
listed in this structure can be referred to in the user function.
148
C filters and functions
The function ‘testustats’ is a sample function using USERSTATS as
an argument. It can be found in the ‘\usercode\formula’ directory.
C filters and functions
149
/******************************************************************************
** Copyright 1990/91 Earth Resource Mapping Pty Ltd. This document contains
** unpublished source code of Earth Resource Mapping Pty Ltd. This notice does not
** indicate any intention to publish the source code contained herein.
** FILE: ERMAPPER/include/ERSStats.h
** CREATED: Tue Feb 12 21:24:31 WST 1991
** AUTHOR: David Hayward
** PURPOSE: The dataset region statistics structure.
******************************************************************************/
#ifndef ERSSTATS_H
#define ERSSTATS_H
#include “ERStypes.h”
typedef struct ERSStats {
STRING dsdir;/* dataset header directory */
STRING dsfname;/* dataset header filename */
STRING rname;/* region name */
INT32 nr_band;/* number of bands used to generate stats */
INT32 *p_bandnr_vec;/* array of band numbers used (note band 1
** is 1, not 0)*/
/*
** Following are stored on disk
*/
INT32 *p_nr_non_null_cells_vec; /* nr of non null cells array */
INT32 *p_nr_null_cells_vec;/* nr of null cells array */
double *p_min_vec;/* minimum value array*/
double *p_max_vec;/* maximum value array */
double *p_mean_vec;/* mean value array */
double *p_median_vec;/* median value array */
double **p_p_cov;/* covariance matrix */
double **p_p_corr;/* correlation matrix */
double **p_p_inv;/* Inverse of matrix */
/*
** Following are calculated on the fly
*/
double *p_hectares_vec; /* non-null area in hectares */
double *p_acres_vec; /* non-null area in acres */
double *p_cov_eval;/* Covariance eigenvalues */
double *p_corr_eval;/* Correlation eigenvalues */
double **p_p_cov_evec;/* Covariance eigenvectors (PCs) */
double **p_p_corr_evec;/* Correlation eigenvectors */
double detcov;/* Determinant of covariance matrix */
double detcorr;/* Determinant of correlation matrix */
double *p_stdev;/* Standard deviation (using n) */
double *p_stdevnm1;/* Standard deviation (using n-1) */
} ERSStats;
#endif
150
C filters and functions
Creating Color Tables
Color Lookup tables define how ER Mapper will transform digital
values to colors in pseudocolor layers.
Color Lookup Table files are held in the “lut” directory. Add any new
lookup tables in this directory so that they will appear in the Color
Table menu in ER Mapper’s Algorithm dialog box.
The lookup table files are text files, each holding an array of 256 lines
of four entries each. The first entry is the pixel lookup value and runs
from 0 to 255 down the array. The other three entries are the Red,
Green and Blue values that will be used to display that pixel value.
A variety of lookup tables is supplied with ER Mapper. In addition,
you can create your own tables tailored to your needs.
To select a Lookup Table
1. In the Algorithm dialog box, select the ‘Pseudocolor’ Color Mode.
2. Select the desired Lookup Table from the Color Table drop down
list.
To create a new Lookup
Table
1. Create a new color lookup table file.
Use an existing file as a template and follow the structure in the
“Look up table files (.lut)” chapter.
2. To include the lookup table in the lookup table menu, make sure the
file is in the “lut” directory and has a ‘.lut’ extension.
To generate a linear Color
Lookup Table
If your color lookup table is to consist of a linear gradation from one
color to another, you can use the ‘makelut’ utility supplied with
ER Mapper to help you generate it. ‘makelut’ creates a Color Lookup
Table which adjusts one specified value to another, and outputs the
Color Lookup Table to the ‘makelut’ standard output path. This may
be piped into an ER Mapper ‘.lut’ file.
To generate a Color Lookup Table:
1. Bring up a Command Prompt window.
2. Type in the CLUT utility command:
makelut -n "CLUT_name" iR iG iB nR nG nB >
ERMAPPER\lut\CLUT_filename.lut
Where:
•
Creating Color Tables
-n "CLUT_name" is the name of lookup table to be displayed in
Lookup Table menu
151
•
iR iG iB are the Red Green Blue values of initial color
•
nR nG nB are the Red Green Blue values of last color
•
ERMAPPER\lut is the ER Mapper Color Lookup Table directory
•
CLUT_filename is the file name of color lookup table.
The values are specified in the range 0-255, and the ‘makelut’ utility
correctly generates the values in the 0-65K range.
Example: a 2-color
Lookup Table
For example, to generate a Color Lookup Table that runs from red to
blue:
makelut -n "Red->Blue" 255 0 0 0 0 255>
ERMAPPER\lut\red_blue.lut
Likewise, the command:
makelut -n "Brown->Green" 165 42 42 124 255 0 >
ERMAPPER\lut\brown_green.lut
generates a brown to lawn green color lookup table which can be
useful for vegetation indices.
Example: a
multicolor Lookup
Table
The example above is for a two color range. However, the “makelut”
program allows for any number of “steps” in each lookup table—the
minimum is 2, that is, a start and end point (RGB value). The
following example ramps from black to red to green to blue to white
in 5 steps.
% makelut 0 0 0 255 0 0 0 255 0 0 0 255 255 255 255
For information about the Lookup Table file format see the
“Look up table files (.lut)” chapter.
Example:
assigning specific
colors to each
grey level
There are two ways to do this:
LUT “LoadMethod = Truncate”
Although there are 256 colors in the LUT table, ER Mapper normally
translates those 256 colors into the ones available on your
workstation display. For example, on 8-bit displays between 25 and
50 colors are reserved by the windowing system.
ER Mapper normally tries to extract colors over the entire range of
colors in the LUT, to result in an image that shows no obvious color
holes.
However, for classification type images, this is not what you want.
You want the LUT to always use the first N LUT entries, so that LUT
color #1 gets mapped to image value 1, LUT color #2 gets mapped
to image value 2, and so on.
To do this, make sure that the .lut file you are creating has the
following line in it:
152
Creating Color Tables
LoadMethod = Truncate
See the “Look up table files (.lut)” chapter for more
information.
1. The “classified image”
Your example image is really a form of “classified” image. Classified
images have the following features:
•
They have names for each class (data value)
•
You can specify a color for each class
•
They are simple to display.
The first thing you need to do is ensure that the .ers file is set up as
a classified image (you could do this as part of the script that creates
the .ers file).
To look at an example classification image, have a look at:
“examples\Shared_Data\ISOCLASS_Landsat_TM_year_1985.er
s”
The following needs to be put in for each class, in the RasterInfo
section:
RegionInfo Begin
Type = Class
RegionName="SomeDescription"
RGBColour Begin
Red = 40000 #note this is 0 to 65535
Green = 50000 #ditto
Blue = 20000 # ditto
RGBColour End
ClassNumber = 3 # e.g. a number from 1 to 255
RegionInfo End
You don’t have to put the color in by editing the file; once the
class details are in the .ers file, you can update class colors by
using the Edit/Edit Class/Region Color and Name menu
option.
Once an image has class information (class number and color), to
display it you use the new “CLASSIFICATION DISPLAY” layer type.
That option takes each pixel value, looks up its color, and displays it
in that color.
Creating Color Tables
153
You can still use formulae within Classification Display layers so
you can still do “IF I1>3 AND I1<=10 THEN i1 ELSE NULL” to show
only classes 4 to 10, or you can do “IF inregion (“some region”) and
not inregion (“another region”) THEN i1 ELSE NULL” to only show the
image within some polygon region.
154
Creating Color Tables
Look Up Table files (.lut)
The lookup table files describe a mapping of numbers to colors, used
to visualize digital data using pseudocolor color mode.
Each of the files contains some information about the color look up
table (LUT) and an array of values which describes the red, green
and blue entries for each lookup value. The lookup values are in the
range 0 to 255 so the entries are in a two dimensional array; 256
lines, each containing:
Lookup value; Red value; Green value; Blue value
The display color values are integers in the range 0 to 65535 which
provides 16 bit color entries.
An example ‘.lut’ file is as follows:
LookUpTable Begin# lookup table definition block
Version = "5.0"
# *.lut file version
Name = "pseudocolour" # name which appears in
# pull-down CLUT selection list
Description = "Standard Pseudocolour"
# internal description
NrEntries = 256
# number of entries (lines)in array
LUT = {
# start of LUT array
0
0
0
65535 # first entry (value 0)
1
0
767
65535 # second entry (value 1)
2
0
1535
65535 # and so on ....
.
.
.
.
.
.
.
.
# entries are:
#pixel red
green
blue values
.
.
.
.
.
.
.
.
.
.
.
.
253
65535
1792
0 # etc
254
65535
1024
0 # until ..
255
65535
256
0 # 256 entries are described
}
# close curly braces to
# indicate end of array
LookUpTable End
LUT file entries
The Lookup Table file entries are as follows.
•
Version (optional): The version of the lookup table file. Used
internally only. The entry is generated by ER Mapper. For
example,
Version = "5.0"
Look Up Table files (.lut)
155
•
Name (optional): The entry appearing on the lookup table menu
list. If not specified the entry will be set to the file name. For
example,
Name = "pseudocolour"
•
Description (optional): A short description of the lookup table.
This entry is optional. It is not used by ER Mapper. For example,
Description = "Standard Pseudocolour"
•
LoadMethod (optional): Obsolete.
•
NrEntries: The number of entries in the lookup table. This entry
must precede the array. The number specified must match the
number of lines in the LUT array and is usually 256. For example,
NrEntries = 256
•
LUT: The RGB color specification for each of the colors.
For more information about creating color lookup tables, see the
“Creating color tables” chapter.
156
Look Up Table files (.lut)
Hardcopy files (.hc)
Hardcopy definition files end with the suffix ‘.hc’ and are found in the
‘hardcopy’ directory. They are used to specify the attributes of each
hardcopy output device.
Hardcopy devices are usually printers, but they can be any type of
raster output device such as filmwriters, plotters, photocopiers and
standard graphics formats.
The example below illustrates the information required by the
hardcopy engine:
# HP Deskjet hardcopy device
# This is a 300 DPI black and white ink-jet printer
#
HardCopyInfo Begin # hard copy device info
Name = "HP DeskJet" # name for device
DotsPerInchAcross = 300 # horizontal resolution
DotsPerInchDown = 300 # vertical resolution
MaximumDotsAcross = 2320 # printable width of paper
MaximumDotsDown = 3100 # printable height of paper
FilterProgram = "hetodeskjet"# dithers to get gray scale
OutputProgram = "lpr -Pdeskjet"# gets data to printer
Gamma Begin
Red
= 1
Green
= 1
Blue
= 1
Gamma End
BackgroundColour Begin# begin background block
Red = 65535
Green = 65535
Blue = 65535
BackgroundColour End# end background block
HardCopyInfo End # close block
Explanations of the entry lines are listed below:
•
Name: The descriptive name of the hardcopy device, for
example:
Name = “HP DeskJet”
•
DotsPerInchAcross: The widthwise pixel density in number of
dots(pixels) per inch, for example:
DotsPerInchAcross = 300
•
DotsPerInchDown: The heightwise pixel density in number of
dots (lines) per inch.
DotsPerInchDown = 300
Hardcopy files (.hc)
157
•
MaximumDotsAcross: The width of a “page” in pixels. For
example,
MaximumDotsAcross = 2320
•
MaximumDotsDown: The height of a “page” in pixels. For
example,
MaximumDotsDown = 3100
•
FilterProgram: The program which converts the raw ER Mapper
ermhe output into a format suitable for the hardcopy device. If no
conversion is necessary, specify “cat”. For example,
FilterProgram = “hetodeskjet”
•
OutputProgram: The program which actually sends the data to
the hardcopy device. For example,
OutputProgram = “lpr -Pdeskjet”(Unix only)
•
Gamma Block: This block defines the gamma correction settings
for adjusting the red, blue and green components of the output
image. This allows you to compensate for variations in colors in
printers.
Gamma Begin
Red = 1
Green = 1
Blue = 1
Gamma End
•
BackgroundColour Block: This block defines the background
color of the output image. There is a value for each of Red, Green
and Blue which can be between 0 and 65535. The default
background is white which looks like the following.
BackgroundColour Begin
Red = 65535
Green = 65535
Blue = 65535
BackgroundColour End
158
Hardcopy files (.hc)
•
HardcopyInfo: Hardcopy definition files use the above hardcopy
device attributes contained within the HardcopyInfo Begin and
HardcopyInfo End statements:
HardcopyInfo Begin
HardcopyInfo End
•
Comments: Comments can also be included in the hardcopy
definition file, by including a hash (#) symbol as the first
character on the comment line.
# HP DeskJet hardcopy device
# This is a 300 DPI black & white ink-jet
# printer
Comments may also be made at the end of lines.
•
Paper Types: Multiple hardcopy definition files for the one
hardcopy device will need to be defined for the different sizes of
sheet paper, including continuous paper, used with the hardcopy
device. ER Mapper uses a different hardcopy definition file ‘.hc’
for each paper size. Change the MaximumDotsDown and
MaximumDotsAcross for the particular paper size.
Additional information about the ‘.hc’ files and filter programs
can be found in the "Hardcopy processing and filter
programs" chapter in this Manual. A list of devices currently
supported by ER Mapper is given in Appendix A "Supported
hardcopy formats and devices" in the ER Mapper User Guide .
Hardcopy files (.hc)
159
160
Hardcopy files (.hc)
Menu and toolbar files (.erm) and (.bar)
Each of the ER Mapper menus and toolbars is defined by a
configuration file. These files are stored in the ‘config’ directory. The
menu and toolbar file structures are virtually identical except that
the toolbar file must specify the icon to be included on the toolbar.
There are a fixed number of menu files but you can edit them to add
new options. On the other hand you can have any number of toolbar
files so you can add complete toolbars if you want, as well as editing
the existing ones. Any ‘.bar’ files in the ‘config’ directory are
automatically listed in the ER Mapper toolbar menu in alphabetical
order.
The files can be edited using your ASCII editor or the editor included
in ER Mapper under the Utilities / User Menu / Edit a File and the
Utilities / Toolbars / Edit a Toolbar option.
Example entries from a toolbar file are:
"New" "New Image Window" CALLBACK new_alg_cb
"Open" "Open Algorithm into Image Window" CALLBACK load_alg_cb
"Copy_Window" "Copy Window and Algorithm" BATCH "Copy_Window"
"Save" "Save Algorithm" CALLBACK save_alg_cb
"Save_As" "Save Algorithm As" CALLBACK save_alg_as_cb
Example entries from a menu file are:
"&Raster Cells to Vector Polygons..."
"" "erm_rtov -x"
"&Calculate Statistics" "" "ersstats -x"
"C&lassification" "" MENU
"&Supervised Classification" "" "erm_svclass -x"
"&ISOCLASS Unsupervised Classification" "" "erclassx"
"&View Scattergrams" "" CALLBACK scatter_cb
"&Edit Class/Region Color and Name..." "" "erm_classedit"
END "" PIN
Menu and toolbar entries are made up of three parameters:
•
1. Menu/button option: For menu files, the text to be displayed
on the menu, typed within double quotes. For example,
"Classification"
For toolbar files, the name of the button picture (.tif) file. The tiff
file must be in the ‘icons’ directory and must be a 24-bit 16 x 16
pixel tiff file. For example,
"Mosaic_Datasets"
refers to the ‘Mosaic_Datasets.tif’ file.
Menu and toolbar files (.erm) and (.bar)
161
•
2. Tool tips text: For toolbar files this text is displayed when a
user points to the tool button with the mouse cursor. The text
must be enclosed in two sets of quotation marks. For menu files
the text is not used but the parameter must be present as a
minimum of two double quotes. For example,
"Zoom Tool"
""
•
3. Program call: A command to be executed when the option is
selected. This can be one of the following forms:
•
programname and switches - to specify an external program.
For example,
"erm_rtov -x"
•
CALLBACK functionname - for calling internal ER Mapper
functions. These are listed below. For example,
CALLBACK zoom
•
BATCH scriptname - for specifying a batch script to be run.
For example,
BATCH "Copy_Window"
If you specify a batch script you can have up to 5 additional
parameters to pass into the batch script.
Submenus
Options in menu files can be grouped together in submenu blocks.
The beginning of a submenu is indicated by a menu declaration entry
and the end of a submenu is indicated by a menu end statement. The
entries in between will appear on the submenu. For example, in the
submenu block:
"C&lassification" "" MENU
"&Supervised Classification" "" "erm_svclass -x"
"&View Scattergrams" "" CALLBACK scatter_cb
"&Edit Class/Region Color and Name..." "" "erm_classedit"
END ""
the menu declaration entry
"C&lassification" "" MENU
indicates that the following entries should be placed on a submenu
and the menu end statement
END ""
indicates the end of the submenu options. The double quotes must
be included. The optional Unix only word ‘PIN’ specifies that the
menu must be able to be pinned up by the user.
162
Menu and toolbar files (.erm) and (.bar)
Menu option
keyboard
selection
In the menu text, an ampersand (&) accelerator key is placed in front
of the letter to be used for choosing options from the menu using the
Alt key. These are shown as underlined letters on the menu in
ER Mapper. The first occurrence of the underlined letter is always
underlined regardless of the position of the Ampersand. The program
is case sensitive. A different letter should be chosen for each menu
option. For example,
"Quick &Zoom" “” MENU
shows up on the menu as:
Quick Zoom
Option separators
Entries with dashes in the menu name are interpreted as separators
in menus and spaces in menu bars. Thus,
“--------------------” “”
""
Available callback
options
The following callback options are available:
•
annotate_arcinfo_cb
•
annotate_region_cb
•
annotate_vector_cb
•
anntenna_pattern_correction_cb
•
batch_job_cb
•
close_current_dest_cb
•
dig_config_cb
•
dig_session_cb
•
edit_alg_cb
•
exit_cb
•
extract_traverse_cb
•
gcp_cb
•
geocode_tool_cb
•
geoposition_cb
•
import_polarimetric_cb
•
layover_and_shadow_map_generation_cb
Menu and toolbar files (.erm) and (.bar)
163
164
•
load_alg_cb
•
load_alg_from_menu_cb
•
load_any_cb
•
load_any_new_surface_cb
•
load_vds_cb
•
new_alg_cb
•
open_hardcopy_cb
•
open_window_cb
•
open_window_on_cdev_cb
•
pagesize_cb
•
polarisation_signature_cb
•
position_cb
•
preferences_cb
•
profile_cb
•
refresh_cb
•
sar_image_simulator_cb
•
save_alg_as_cb
•
save_alg_as_ds_cb
•
save_alg_as_vds_cb
•
save_alg_cb
•
save_image_to_clipboard_cb
•
scatter_cb
•
set_mode_pointer_cb
•
set_mode_roam_cb
•
set_mode_zoom_rect_cb
•
slant_to_ground_conversion_cb
•
speckle_noise_reduction_cb
Menu and toolbar files (.erm) and (.bar)
•
stop_cb
•
texture_analysis_cb
•
zoom_buttons_cb
The following are parameters accepted by some callbacks.
•
1
•
2
•
3
•
4
•
5
•
ZOOM_BUTTON_ALLDS
•
ZOOM_BUTTON_ALLRASTDS
•
ZOOM_BUTTON_ALLVECDS
•
ZOOM_BUTTON_CONTENTS
•
ZOOM_BUTTON_CURRENTDS
•
ZOOM_BUTTON_GEOLINK_NONE
•
ZOOM_BUTTON_GEOLINK_OVERVIEW_ROAM
•
ZOOM_BUTTON_GEOLINK_OVERVIEW_ZOOM
•
ZOOM_BUTTON_GEOLINK_SCREEN
•
ZOOM_BUTTON_GEOLINK_WINDOW
•
ZOOM_BUTTON_PAGE
•
ZOOM_BUTTON_PREVIOUS
•
ZOOM_BUTTON_ZOOM_TO_WINDOW
•
ZOOM_BUTTON_ZOOMIN
•
ZOOM_BUTTON_ZOOMOUT
Menu and toolbar files (.erm) and (.bar)
165
166
Menu and toolbar files (.erm) and (.bar)
Map Composition files (.ldd)
Map Composition items are included in Annotation/Map Composition
overlays. Map_box and map_polygon objects use the “Attribute”
fields to specify the map item and parameters to be interpreted by
the PostScript generator. The PostScript for the individual map items
is stored in “.ldd” files which define:
•
User Parameters, to be specified by the user (for example, text
height);
•
procedures to be processed to generate PostScript variables and
procedures; and
•
PostScript include files which contain the main PostScript
executable and library code.
Together these supply the PostScript required to display each Map
Composition item.
To create a new Map Composition item you need to create a new
“.ldd” file and new PostScript include files. Legend Definition “.ldd”
files are stored in the directory “legendrules”. PostScript include files
are stored in the directory “legendps”. You also need to store a map
item icon to be used in ER Mapper. The icon should have the same
name as the “.ldd” file with the extension “.tif” and be stored in the
same “legendrules” directory. The tiff file must be a 24-bit 64 x 64
pixel file. You can create this using ER Mapper to print to the
“Graphics/TIFF_64x64_24bit.hc” hardcopy device.
Map Composition files specify characteristics of a Map Composition
item. There are currently twenty types of Map Composition item
available, stored in twenty subdirectories of the “legendrules”
directory. The directories are:
Map Composition files (.ldd)
•
Algorithm
•
ClipMask
•
Dynamic_Link
•
Geology
•
Grid
•
Image
•
Legend_Item
•
Logo
•
Map_Symbols
•
North_Arrow
167
•
PostScript
•
Road_Maps
•
Scale_Bar
•
Sea_Ice
•
Symbols
•
Text
•
Title
•
Title_Block
•
Wells
•
ZScale
There is also a set of subdirectories containing the ER Mapper
Release 4 Map Composition items. These are included to maintain
backward compatibility.
168
Map Composition files (.ldd)
An example of a simple .ldd file that draws the ER Mapper logo is
shown below.
LegendRule Begin
Description= "ER Mapper Logo"
MapHints Begin
FastPreviewHint= No
PageRelativeHint= Yes
SquareHint= Yes
WidthHint= 0.3
HeightHint= 0.15
LeftMarginHint= 0.0
RightMarginHint= 0.0
TopMarginHint= 0.0
BottomMarginHint= 0.0
MapHints End
UserParameter Begin
Name = "Backdrop Color"
Type = Color
Default= "254,254,254"
UserParameter End
Generate Begin
Type = BoundingBox
Generate End
PSLibIncludeFiles Begin
File = "PSLib/lib_Color.ps"
PSLibIncludeFiles End
PSExecIncludeFiles Begin
File = "Logo/ER_Mapper_Logo.ps"
File = "Logo/ER_Mapper_Logo.eps"
File = "PSExec/Reset.ps"
PSExecIncludeFiles End
LegendRule End
The “.ldd” files are made up of the following entries.
LegendRule block
The entire “.ldd” file is encapsulated in a LegendRule block, so the
first line in the file is LegendRule Begin and the last line is
LegendRule End.
•
Description: The Description entry contains a string description
within double quotes. For example,
Description = "ERM Logo"
•
Map Composition files (.ldd)
MapHints Block: Specifies how a preview version of the map
legend is to be displayed.
169
UserParameter
Block
•
Generate Block: Specifies procedures to be executed. See
"Generate block" below.
•
UserParameter Block: These blocks define parameters that the
•
PSLibIncludeFiles: The PostScript library procedure definitions.
•
PSExecInclude Files Block: The PostScript files to be included
•
Name: A text string enclosed in double quotes to become the
name of the PostScript variable. For example,
user sets within ER Mapper’s Map Composition Edit Map Item
window, on loading the item. They are converted to variable
definitions by the PostScript generation program. The variable
definitions have the name specified by the “name” field, the value
defined by the “default” field (or that entered by the user), while
the “type” field determines the structure of the variable. All fields
are required.
See "PSLibInclude block" below.
during execution. See "PSExecInclude block" below.
Name = "Units"
If the name has spaces embedded, these are stripped when
forming the corresponding PostScript variable definition.
•
Type: The “Type” of the parameter determines how the
parameter value is processed. The type is specified without
double quotes. The following types are allowable and are
discussed on the next page:
•
Algorithm
•
YESNO
•
String
•
Number
•
List
•
Color
•
Font
•
DynamicLink
Type = List
170
Map Composition files (.ldd)
•
AllowedValues Block: Used to specify allowable values of the
parameters of type “List”. The values are listed using “Item”
specifiers.
AllowedValues Begin
Item = "Miles"
Item = "Kilometers"
AllowedValues End
•
Default: The value specified in the variable definition unless
overridden by the user.
Default = "Kilometers"
•
DlinkParam Block: This block must be included for parameters of
type “DynamicLink”. See the section on DynamicLink type
parameters below.
Allowable
Parameter types
The allowable types are:
Algorithm
Brings up an algorithm chooser, and converts the name to a
PostScript string variable.
YES/NO
A true/false or yes/no type of value which takes the form of a tick
box in the Edit Map Item window. This is converted to a PostScript
Boolean variable.
Name = "Labels At Top"
Type = YesNo
Default = "YES"
converts to:
/LabelsAtTop true def
String
Takes the text in double quotes and converts it to a PostScript string
by enclosing it in brackets ( ). For example,
Name = "Title"
Type = String
Default = "Image"
converts to:
/Title (Image) def
Number
Expects a single integer or floating point number which ermps_map
converts to a double precision number.
Name = "Tick Mark Length"
Type = Number
Default = "5"
converts to:
/TickMarkLength 5.0 def
Map Composition files (.ldd)
171
List
The “Items” in the “AllowedValues” block appear as items in a
chooser for the field in the Edit Map Item window. The variable is
set to one of these string values.
Name = "Units"
Type = List
AllowedValues Begin
Item = "Miles"
Item = "Kilometers"
AllowedValues End
Default = "Kilometers"
converts to:
/Units (Kilometers) def
Note that the chosen list item is always converted to a PostScript
string variable.
Color
Expects a string value, enclosed in double quotes, consisting of three
numbers representing the RED, GREEN and BLUE values for the
color, on a scale of 0 to 255. On output, these values are converted
to a form suitable for use by the PostScript setrgbcolor operator,
being 3 values scaled from 0 to 1. For example,
Name = "Color"
Type = Color
Default = "128 128 128"
becomes:
/Color 0.501961 0.501961 0.501961 def
Font
172
Takes the string that follows and converts it into a PostScript literal
string by preceding it with a slash. In the Edit Map Item window,
this is presented as a menu of the following standard PostScript
fonts.
•
AvantGarde-Book
•
AvantGarde-BookOblique
•
AvantGarde-Demi
•
AvantGarde-DemiOblique
•
Bookman-Demi
•
Bookman-DemiItalic
•
Bookman-Light
•
Bookman-LightItalic
•
Courier
•
Courier-Bold
Map Composition files (.ldd)
•
Courier-BoldOblique
•
Courier-Oblique
•
Helvetica
•
Helvetica-Bold
•
Helvetica-BoldOblique
•
Helvetica-Narrow
•
Helvetica-Oblique
•
NewCenturySchlbk-Bold
•
NewCenturySchlbk-BoldItalic
•
NewCenturySchlbk-Italic
•
NewCenturySchlbk-Roman
•
Palatino-Bold
•
Palatino-BoldItalic
•
Palatino-Italic
•
Palatino-Roman
•
Symbol (Symbol)
•
Times-Bold
•
Times-BoldItalic
•
Times-Italic
•
Times-Roman
•
ZapfChancery-MediumItalic
•
ZapfDingbats (ZapfDingbats)
For example,
Name = "UnitsFont"
Type = Font
Default = "Times-Bold"
becomes:
/UnitsFont /Times-Bold def
Map Composition files (.ldd)
173
DynamicLink
Loads the output from a dynamic link into the object bounding box.
When this type of parameter is specified a DlinkParam Block must be
included specifying the dynamic link chooser and PostScript
generation and link initialization programs to run. For example,
UserParameter Begin
Name = "Vector File"
Type
= DynamicLink
Default
= "$$,.erv,ermps_map_ervec,ermps_ervec"
DlinkParam Begin
ChooserString
= ".erv"
LinkProgram
= "ermps_map_ervec"
InitProgram
= "ermps_ervec"
DlinkParam End
UserParameter End
Generate Block
The Generate Block consists of a list of “Type” fields. Each specifies
a procedure to be executed. The procedures use algorithm variables
and generate PostScript variables and procedures. Output is in
PostScript coordinates (using points or pixels).
Allowable Types are shown below.
AlgorithmImagePS
Runs an ER Mapper algorithm, and generates a PostScript file that
will draw the resulting image. The algorithm that is run must be
specified by a user parameter called “AlgorithmName”. A PostScript
variable ERM_ALGORITHM_IMAGE_PS_FILE is generated, which
contains the name of the PostScript file which contains the algorithm
image. This will be drawn into the bounding box of the object by
using the PostScript “run” directive. For example:
Type = ERM_ALGORITHM_IMAGE_PS_FILE run
will draw the algorithm into the bounding box of the map
composition item. ER Mapper removes the temporary PostScript file,
which is stored in a directory defined by environment variable
“$ERMTMP”. For example,
Type = AlgorithmImagePS
Progirst
Processed before other map items, typically used for clip masks.
Linepath
Generates a PostScript procedure “ERM_LINEPATH”.
Boundingbox
Converts the bounding box coordinates to PostScript point positions
and specifies them as four variables:
174
•
ERM_BBOX_BLX,
•
ERM_BBOX_BLY,
•
ERM_BBOX_TRX and
•
ERM_BBOX_TRY.
Map Composition files (.ldd)
ScaleBar
Specifies the following variables.
•
ERM_SCALE: Floating point value of scale factor, e.g. 1:250000,
value of ERM_SCALE would be 250000.000000
•
ERM_SCALEBAR_LABELS_POINTSIZE: Height (in points =
1/72.27 inch) of labels area above the scale bar proper. This can
be used for the point size of the text for the labels, but should be
constrained in the actual PSInclude PostScript to be bigger than
some minimum, and smaller than some maximum point size.
•
ERM_SCALEBAR_UNITS_POINTSIZE: Height (in points =
1/72.27 inch) of units area below the scale bar proper. This can
be used for the point size of the text for the labels, but should be
constrained in the actual PSInclude PostScript to be bigger than
some minimum, and smaller than some maximum point size.
•
ERM_SCALEBAR_MILES_CENTER/ERM_SCALEBAR_KM_CENTER:(
x, y) position of center of actual scale bar.
•
ERM_SCALEBAR_MILES_HALFHEIGHT/ERM_SCALEBAR_KM_HALF
HEIGHT: Half-height (above and below centerline) of actual scale
bar
•
ERM_SCALEBAR_MILES_NR_DIV/ERM_SCALEBAR_KM_NR_DIV:
Number of divisions in the scale bar - is almost certainly going to
be the same as NumberOfDivisions UserParameter, but
ERM_SCALEBAR_KM_NR_DIV and its MILES counterpart should
be used in the PostScript.
•
ERM_SCALEBAR_MILES_INFO/ERM_SCALEBAR_KM_INFO:
Array of x-position, y-position of centerline of actual scale bar,
positions are of division lines/tick marks.
There is one of these (ERM_SCALEBAR_MILES_INFO) for a Miles
scale bar, and the other (ERM_SCALEBAR_KM_INFO) for a
Kilometers scale bar.
•
ERM_SCALEBAR_MILES_LABELS_INFO/
ERM_SCALEBAR_KM_LABELS_INFO: Array of: x-position, yposition, text of labels that are to appear above the actual scale
bar.
All x and y positions and half-height are expressed in output
PostScript units (pixels). The x/y positions for tickmarks are
based on the value of the UserParameter “NumberOfDivisions”.
If this is not set in any UserParameter block, then a default of 3
is used for this.
Map Composition files (.ldd)
175
Special User Parameter
“GeodeticScaleLatitude”
for scale bars
The scale bar generation logic will respond to a User Parameter
called “GeodeticScaleLatitude”. If this User Parameter appears in a
legend item definition “.ldd” file, then, for an image in a GEODETIC
(Latitude/Longitude) projection, the value of
“GeodeticScaleLatitude” will be used to calculate the scale bar
parameters. For example, if “GeodeticScaleLatitude” is set to 20,
then the scale bar will be generated for latitude 20 degrees (North
or South). If there is no “GeodeticScaleLatitude” User Parameter, the
scale bar for a GEODETIC projection will be calculated for the latitude
of the actual position of the scale bar on the image.
ZScale
•
ERM_ZSCALE_COLORMAP: Array of (256) colours comprising the
colormap, running from lowest to highest index. Note: do not rely
on there being 256 colors in the colormap - key any PostScript
loops off the length of the array divided by 3. The values for each
entry are in the order RED, GREEN, BLUE, scaled to 1.0, suitable
for PostScript setrgbcolor operator.
•
ERM_ZSCALE_LABELS_INFO: Array of number (between 0.0 and
1.0) and label string. The number is the distance from the bottom
of the colormap (scaled to 1.0) of the label, and the label string
is the actual label that is to appear at this point on the colormap.
There are NumberOfDivisions+1 pairs of entries in this array.
NumberOfDivisions is set as a UserParameter - if it is not set, the
default is 5.
NorthArrow
•
ERM_NORTHARROW_ROTATION: A real-valued number of
degrees counterclockwise that the northarrow on the output has
to be rotated from pointing vertically upward, to correspond to
geographic north on the image.
Grid
•
GT_LL_LABEL;
•
LG_LLLINEGRID:
•
LG_LLTICKGRID:
•
GT_LL_TICK;
•
LG_ENTEXTGRID:
•
GT_EN_LABEL;
•
LG_ENLINEGRID:
•
LG_ENTICKGRID:
•
GT_EN_TICK
176
Map Composition files (.ldd)
PSLibInclude
Block
This block lists the PostScript library procedure definitions. These are
reusable PostScript routines that are only included once for the
whole map (that is, once for all items). It does not include any
executable code. The PostScript files are stored in the “legendps”
directory.
The library files currently available are:
PSExecInclude
Block
•
libitemlabel.ps - item labelling utility routines
•
libstr.ps - character string handling routines
•
libtext.ps - text formatting routines
•
The convention is to name library include files with a prefix of
“lib”.
This block lists the PostScript files to be included during execution.
These files contain the actual PostScript executable commands which
process the procedures and variables defined in the preceding
blocks.
The PostScript files are stored in the “legendps” directory. They may
call procedures defined in PSLibInclude PostScript library files.
Map Composition files (.ldd)
177
Example
178
In this example the item “Title” is added to an Annotation/Map
Composition overlay. The PostScript generation program uses the
item definition file “Title.ldd” to help generate the PostScript for the
item. The “Title.ldd” file lists the user parameters which are made
available to the user as editable attributes. Next, it calls on the
PostScript variable generation procedure BOUNDINGBOX to be
processed. Then, it includes the PostScript library file “libtext.ps”
containing text formatting routines, and the files “setcolor.ps” and
“title.ps” which contain executable procedures..
Map Composition files (.ldd)
LegendRule Begin
Description = "Title"
UserParameter Begin
Name = "Title"
Type = String
Default = "Image"
UserParameter End
UserParameter Begin
Name = "Color"
Type = Color
Default = "128 128 128"
UserParameter End
UserParameter Begin
Name = "Font"
Type = Font
Default = "Helvetica"
UserParameter End
UserParameter Begin
Name = "Min Font Point Size"
Type = Number
Default = "8"
UserParameter End
UserParameter Begin
Name = "Max Font Point Size"
Type = Number
Default = "32"
UserParameter End
Generate Begin
Type = BOUNDINGBOX
Generate End
PSLibIncludeFiles Begin
File = "libtext.ps"
PSLibIncludeFiles End
PSExecIncludeFiles Begin
File = "setcolor.ps"
File = "title.ps"
PSExecIncludeFiles End
LegendRule End
An example PostScript include file setcolor. ps contains the
following:
%!
Color setrgbcolor
Map Composition files (.ldd)
179
An example PostScript include file title.ps” is as follows:
%%
%% Place the title in the centre of the bounding box defined
%% with a font size to fill the box or use the minimum or
maximum
%% font size to prevent the text becoming to small or too large
%%
Color setrgbcolor
% set variables for box width and height
/box_ht ERM_BBOX_TRY ERM_BBOX_BLY sub def
/box_wdth ERM_BBOX_TRX ERM_BBOX_BLX sub def
% set the font size to fit the box
Font MinFontPointSize MaxFontPointSize box_ht box_wdth Title
FitFont
% display the text in the centre of the box
ERM_BBOX_BLX box_wdth 2 div add
ERM_BBOX_BLY height Title StringHeight sub 2 div add
moveto
Title centertext
The following PostScript is generated by ER Mapper to produce the
“Title” item.
(many pages of PostScript created by the PostScript generation
program setting up common variables and procedures)
% PostScript variables created from UserParameter
specifications in "Title.ldd" and
% edited object attributes
/Title (Australia DTM) def
/Color { 1.000000 0.117647 0.000000 } def
/Font /Helvetica def
/MinFontPointSize 8.00000000000000000 def
/MaxFontPointSize 32.00000000000000000 def
% PostScript variables defined by the Generate BoundingBox
command in "Title.ldd"
/ERM_BBOX_BLX 40 def
/ERM_BBOX_BLY 39 def
/ERM_BBOX_TRX 234 def
/ERM_BBOX_TRY 93 def
...
(a few pages of code included from "text.ps" containing
common text variables and procedure definitions)
...
% PostScript code included from "startup.ps"
180
Map Composition files (.ldd)
%!
Color setrgbcolor
% PostScript code included from "title.ps"
%%
%% Place the title in the centre of the bounding box
defined
%% with a font size to fill the box or use the minimum
or maximum
%% font size to prevent the text becoming to small or
too large
%%
Color setrgbcolor
% set variables for box width and height
/box_ht ERM_BBOX_TRY ERM_BBOX_BLY sub def
/box_wdth ERM_BBOX_TRX ERM_BBOX_BLX sub def
% set the font size to fit the box
Font MinFontPointSize MaxFontPointSize box_ht box_wdth
Title FitFont
% display the text in the centre of the box
ERM_BBOX_BLX box_wdth 2 div add
ERM_BBOX_BLY height Title StringHeight sub 2 div add
moveto
Title centertext
% Concluding PostScript generated by "ermps_map"
GR
% End of Generated PS
GR
showpage
Map Composition files (.ldd)
181
182
Map Composition files (.ldd)
Dynamic Links
Dynamic Links are used to access data from sources outside ER
Mapper, such as vector or tabular data from a GIS or a database
system, and display it graphically using PostScript. The
‘dynamiclinks.erm’ file defines the menu of Dynamic Links options
available. It is stored in the ‘config’ directory. Edit this file to add new
links. It can be edited using the File Maintenance /
Configuration / Edit Dynamic Links Menu file option from the
Utilities menu.
See the Dynamic Links (vector layers) chapter in the ER
Mapper User Guide for information about using the available
Dynamic Link options. In this manual, see the “Dynamic Links
program interface” chapter for creating new Read Only and
Read/Write dynamic link interfaces.
Menu entries
Menu items are specified by single line entries with up to 8
parameters, 5 required and 3 optional. If any optional parameter is
specified all previous optional parameters must also be specified (as
null parameters "" if necessary) so that the parameter number is
correct.
Selected entries from the file are shown below.
Dynamic Links
183
In the examples below some of the entries wrap around because
they are wider than the page. However, they must be entered
as single lines in the file.
"Contours" "Contours" "ermpscontours" TRUECOLOUR
"$$SCRIPT=Dlink_Contours.erb $DEFAULT $$MANAGERELATIVEPATHS"
"ermpscontours"
# [03]
"Grid Datasource Points" "Grid Datasource Points"
"ermps_display_grid_datasource" MONOCOLOUR
"$$SCRIPT=DlinkDisplayGridDatasourcePoints.erb"
"ermps_display_grid_datasource"
"Grid Datasource TIN" "Grid Datasource TIN"
"ermps_display_grid_datasource" MONOCOLOUR
"$$SCRIPT=DlinkDisplayGridDatasourceTIN.erb"
"ermps_display_grid_datasource"
# end [03]
"AutoCAD DXF" "DXF Link" "ermps_dxf" TRUECOLOUR ".dxf"
"ermps_dxf"
"MicroStation DGN File" "DGN Link" "ermps_dgn" TRUECOLOR
".dgn" "erminit_dgn"
"External Vector formats" "" MENU
"GeoImage" "GeoImage Link" "ermps_geoimage" MONOCOLOUR ".geo"
"ermps_geoimage"
"Geocoded Monocolor PostScript" "Geocoded Monocolor
PostScript Link" "ermps_erp" MONOCOLOUR ".erp " "erminit_ers"
"Geocoded Truecolor PostScript" "Geocoded Truecolor
PostScript Link" "ermps_erp" TRUECOLOUR ".erp" "erminit_ers"
END
"Tabular Data" "" MENU
"Symbols" "Symbols Link" "ermps_symbols" TRUECOLOUR ".txt"
"Table of data shown as Circles" "Table of Data as Circles
Link" "ermps_table_circle" MONOCOLOUR ".tbl" "erminit_en0"
"EDIT" "erm_link"
"Test R/W link" "Test link for Geodass query"
"ermps_table_circle" MONOCOLOUR ".tbl" "erminit_en0" "EDIT"
"0_erm_link"
"Table of Circles with Rotation" "Table of Data with
Rotation Link"
"ermps_table_circle" MONOCOLOUR ".tbl"
"erminit_any" "EDIT" "erm_link"
"Table of data shown as Outline Circles" "Table of Data Outline Link" "ermps_table_outline" MONOCOLOUR ".tbl"
"erminit_en0" "EDIT" "erm_link"
END
184
Dynamic Links
Submenus
Menu items can be grouped into submenus. The beginning of a
submenu is indicated by a menu declaration entry and the end of a
submenu is indicated by a menu end statement. The entries in
between will appear on the submenu. Submenu entries are indented
by convention, this is not necessary for ER Mapper to read them.
In the example above, the entry:
"External Vector formats" "" MENU
defines a submenu block. The first parameter "External Vector
formats" defines the text to appear on the menu. The second
parameter is a pair of double quotes "". The third parameter is the
keyword MENU. The lines that follow define the available links, and
the submenu is terminated with the END entry.
Menu entry
parameters
The parameters in a menu entry are:
1. Menu option: The text that is displayed on the menu button, typed
within double quotes. For example,
"MicroStation DGN File"
2. Description: A description field enclosed in double quotes. In the
Algorithm window, when you add a dynamic link layer, this is shown
as the layer name in the layer list. This parameter is required but can
be just two sets of double quotes. Examples are:
"DGN Link"
""
3. PostScript generation program call: The name of the translation
program to extract the data and generate the PostScript. By
convention, the names of these programs begin with “ermps_”. For
example,
"ermps_dgn"
See “PostScript generation” above.
4. PostScript type: This can be:
•
MONOCOLOUR
•
TRUECOLOUR
MONOCOLOUR means the resultant PostScript will be shown as a
single color. TRUECOLOUR shows full color PostScript but is slower
to display.
For example,
MONOCOLOUR
Dynamic Links
185
“COLOUR” must have the English spelling.
5. Link chooser (optional) Often some sort of user selection is needed
to specify what data is to be extracted from the link. This parameter
specifies how the source data is to be chosen. It may contain one of
six types of entries. For example,
"$$CHOOSER=arc_chooser $DEFAULT"
".dxf"
See the “Link chooser parameter” and “Chooser program”
sections.
The name of the program which
compares information about the current ER Mapper coordinate space
and extents with the same information from the target data source.
By convention, the names of these programs begin with “erminit_”.
If this field is not specified, ER Mapper assumes that the data coming
from the link is valid in any coordinate space.
6. Initialization program (optional)
The initialization program is described in the “Link
initialization” section.
7. EDIT flag (optional)This parameter is set to "EDIT" if the data can
be edited or annotated within ER Mapper. Syntax is:
"EDIT"
See the “Dynamic Links program interface” chapter for
information on editable links.
8. Edit program (optional) The edit program to run. This parameter
must be present if the EDIT flag is included. For example,
"erm_link"
To add a Dynamic Link
option
1. Decide where on the menu you want the option to appear.
2. Edit the “dynamiclinks.erm” file using your ASCII editor or by
selecting the “File Maintenance / Configuration / Edit Dynamic
Links Menu file” option from the Utilities menu.
3. Insert menu entry in the position you want it to appear.
Your new item will appear on the Edit / Add Vector Layer menu in
the Algorithm dialog box.
186
Dynamic Links
Link chooser
parameter
This field specifies how the source of data for the dynamic link is to
be selected. It may contain one of seven types of entries. (The choice
made during this step is passed to the initialization and PostScript
generation programs via the fifteenth argument. See “Link
initialization” above. The information that gets passed is indicated
for each case below.)
ER Mapper uses the link chooser parameter to determine whether to
use relatve or absolute path handling.
•
No Parameter: When there is no choice to be made and no
parameter needs to be passed to the conversion program this
field is totally omitted (or consists of empty quotes ""). The
syntax is:
""
Nothing is copied to Argument 15.
•
Dataset Chooser: A field beginning with a “.” indicates the
standard ermapper dataset chooser should be used. The icon
appears in the process diagram for the layer
. It displays all
the files with the specified extension from the the current image
dataset directory and subdirectories. For example,
".erv"
ER Mapper uses relative path handling for this chooser.
The file specification of the selected file is passed to Argument
15.
•
Fixed Parameter: When a fixed argument needs to be passed to
the conversion program, without the user making any choice, a
dollar sign “$” precedes the text to be passed to the conversion
program. For example,
"$TODAY"
The text after the $ is passed to Argument 15.
ER Mapper will never use relative path handling for this
parameter.
•
$$ALG Parameter: If the keyword $$ALG is specified, the file
specification of a temporary file containing the current algorithm
is passed. When ER Mapper saves the algorithm to a temporary
file it converts all path names to absolute.
"$$ALG"
•
Dynamic Links
Link Chooser: The name of a list generating program for choosing
other types of files or possible GIS layers, database tables or
other selections. The program name must not begin with “.” or
“$” and must output its list of choices to stdout. For example,
187
"erm_choose_en_grid"
The link chooser icon
is included in the process diagram for
the layer and displays the list. The file specification of the
selection is passed to Argument 15.
•
External Link Chooser: For certain links, the Dataset and Link
Choosers may not be flexible enough. With this option you can
specify an external chooser program. The link chooser icon
is included in the process diagram for the layer and displays the
list. The parameter starts with the keyword sequence
"$$CHOOSER=" and is followed by the name of the chooser
program and its arguments. Thus,
"$$CHOOSER=chooserprog arg1 arg2"
where chooserprog is the program to execute and arg1 and arg2
are arguments to chooserprog.
$DEFAULT is a special argument keyword. It is replaced with the
last value returned by the chooserprog. Thus,
"$$CHOOSER=chooserprog arg1 $DEFAULT"
$$MANAGERELATIVEPATHS is another special argument
keyword which indicates that file or directory specifications that
the link wants ER Mapper to manage are prefaced by “file=” or
“dir=” in the argument string. The arguments are separated by
the pipe “|” symbol. When saving an algorithm, ER Mapper scans
the argument string for “file=” or “dir=” and converts the
subsequent string to a relative path if possible. When re-loading
the algorithm, ER Mapper converts the file or directory
specification back to an absolute path and passes this back to the
link.
To use quotes to specify an argument with imbedded spaces,
precede them with backslashes (\). For example,
"$$CHOOSER=erm_xgettext -p \"Enter the cover\" -s 30"
ER Mapper executes the chooser program when the user presses
the link icon. ER Mapper hangs while the chooser program runs.
When the chooser program exits, ER Mapper reads its stdout and
uses this string as the argument to pass to the link (instead of a
file name).
The argument string has no fixed format; it is up to the dynamic
link program to interpret it.
ER Mapper will handle backslashes, quotes, and newlines in the
argument string, but it must be no longer than 512 bytes. If more
information is required, it is suggested that the information be
put in a file, and the name of the file passed to the link programs.
The handling of non-printable characters in the argument string
is currently undefined.
188
Dynamic Links
•
Batch Script Chooser: With this option you can specify a batch
script to run to determine the source of the data. The syntax is:
"$$SCRIPT=batchfile.erb"
This link can also use the $DEFAULT and
$$MANAGERELATIVEPATH keywords. The syntax is:
"$$SCRIPT=batchfile.erb [$DEFAULT]
[$$MANAGERELATIVEPATHS]”
Dynamic Links
189
190
Dynamic Links
Digitizer files
There are three types of digitizer files used by ER Mapper. They are:
•
the digitizer type file ‘.dtp’ stored in the Program
Files\ERDAS\ERDAS ER Mapper 7.2\digitizer_type directory
•
the digitizer configuration file ‘.dcf’ stored in the Program
Files\ERDAS\ERDAS ER Mapper 7.2digitizer_config directory
•
the digitizer session file ‘.dig’ stored in the Program
Files\ERDAS\ERDAS ER Mapper 7.2\digitizer_config directory.
The syntax of these files is described in this chapter.
Digitizer type file
.dtp
This file contains the format information needed to decode the input
stream from the digitizer into numbers that ER Mapper can work
with. For example,
DigTypeInfo Begin
Comments= "Format_5: FS+XXXXX+YYYYY<CR><LF>"
DigStringLength = 16
LastCharacter = "NL"
XPosition= "2,7"
YPosition= "8,13"
FlagPosition= "0,0"
StatusPosition= "1,1"
ButtonDown = "D"
ButtonUp
= "U"
DigTypeInfo End
The entries are as follows.
•
Comments: A comments field for information. In this example it
indicates the string that the digitizer transmits. For example:
Comments = "Format_5: FS+XXXXX+YYYYY<CR><LF>"
•
DigStringLength: The number of characters in a complete string.
For example,
DigStringLength = 16
•
Digitizer files
LastCharacter: The last character of the string. Allowed options
are :
•
“CR” (Carriage Return)
•
“LF” (LineFeed)
191
•
“NL” (Newline)
For example,
LastCharacter = "NL"
•
XPosition: The position of the x coord substring. For example,
XPosition= "2,7"
•
YPosition: The position of the y coord substring. For example,
YPosition= "8,13"
•
FlagPosition: the position of the flag substring. For example,
FlagPosition= "0,0"
•
StatusPosition: The position of the status substring. For
example,
StatusPosition= "1,1"
•
ButtonDown: The button down character. For example,
ButtonDown
•
ButtonUp: The button up character.
ButtonUp
Notes
Format of .dtp files.
192
= "D"
= "U"
•
This particular format is one of the 30 or so formats specified in
the Altek manual for one of their tablets. The status substring is
usually indicates whether the button was down or up. The Flag
Position is generally used to indicate which button was pressed
on the digitizer mouse (they can have up to 16 different buttons).
•
This information is used as a “set of rules” to decode the digitizer
string into a suitable ER Mapper coordinate, e.g. the DigString
length field tells us when we have grabbed a digitizer “packet”,
the last character lets us check the packet to make sure it is not
corrupted, and the x and y position fields tell us where to look for
the x coord and the y coord, and so on. This gives a great deal of
flexibility when dealing with the multitude of different types of
tablets.
There are 3 example .dtp files:
•
ERMAPPER\digitizer_type\Calcomp.dtp
•
ERMAPPER\digitizer_type\GTCO.dtp
•
ERMAPPER\digitizer_type\Altek.dtp
Digitizer files
These are for the following formats. Other formats will work, as long
as they conform to the 3 rules:
Calcomp digitizers
•
ASCII output
•
last character <cr> or <lf> or <nl>
•
a button down/up character (this can be relaxed to just a button
up character) for stream mode.
Format #0
Format Name Calcomp 2000-A
Format is XXXXXX,YYYYYY,C CR [LF]
The format varies with the tablet size and the resolution. ER Mapper
will work with these other formats, but will need a new .dtp file. The
default shipped Calcomp digitizer type file is for the following tablet
size/resolution combinations.
i.e. For the following combination of tablet size and resolution the
format should be the one shipped (i.e. XXXXX,YYYYY,C,CR [LF])
Size
Size
Size
Size
Size
Size
Tablet size
Resolution
A,B
> 508
C
> 401
D,E,J
<= 1279
A - 12" x 12"
B - 12" x 18"
C - 18" x 24"
D - 24" x 36"
E - 36" x 48"
J - 44" x 60"
Consult your digitizer manual, if you want to use another lpi or
format.
GTCO digitizers
PXXXXX<SP>YYYYY<CR><LF>
Altek digitizers
Format number 5:
FS+XXXXX+YYYYY<CR><LF>
Consult your digitizer manual on how to set the digitizer switch
settings.
ER Mapper accepts digitizer input for:
Digitizer files
•
Defining Rectification control points
•
Cell Coordinate information
•
Cell Profile
•
Annotation system: for creating polygons, polylines and points,
creating map composition polygons, and creating raster regions.
193
For the input to show up on the image and/or dialog, the current
destination must exist and must have the same coordinate space as
the map on the digitizer.
The exception to this is the Rectification Control Point chooser which
accepts the digitizer input without a “TO” image.
Digitizer
configuration file
.dcf
This file contains the communication parameters such as the port
that the digitizer is connected to and the baud rate. This file is
normally created using the Digitizer Config dialog from within
ER Mapper. An example file is shown below.
DigConfigInfo Begin
Name= "/digitizer_config/Altek.dcf"
Port = "/dev/ttya"
BaudRate= 19200
Parity= Odd
StopBits= 2
DataBits= 7
DigConfigInfo End
ER Mapper accepts forward (/) slashes for directory path entries
in files regardless of whether it is the PC or Unix version.
The entries are as follows:
•
Name: The name of the file on disk.
Name = "/erm/ermapper_dev/digitizer_config/Altek.dcf"
•
Port: The serial port to which the digitizer is connected. For
example,
Port = "/dev/ttya" (Unix)
Port = "com1" (PC)
•
BaudRate: The baud rate of the connection. For example,
BaudRate = 19200
•
Parity: The parity of the data, for error detection. Allowable
values are Even or Odd or None. For example,
Parity = Odd
•
StopBits: The number of bits after the data byte signifying the
end of the data byte. Must be 1 or 2. For example,
StopBits = 2
194
Digitizer files
•
DataBits: The number of bits in the data byte. Must be 7 or 8. For
example,
DataBits = 7
Digitizer session
file .dig
The digitizer session file contains the information about a particular
session. It records information specific to the map being digitized
such as the map projection. An example .dig file is:
DigSessionInfo Begin
Name = "/digitizer_config/session1.dig"
Comments= "This is a test for the diginfo functions"
TypeFile= "/digitizer_type/Altek.dtp"
ConfigFile= "/digitizer_config/Altek.dcf"
WarpControl Begin
CoordinateSpace Begin
Datum = "AINABD70"
Projection= "CECASP"
CoordinateType= LL
Units = "METERS"
Rotation= 0:0:0.0
CoordinateSpace End
WarpControl End
DigSessionInfo End
The entries in the .dig file are as follows:
•
Name: The name of the file. For example,
Name = "/digitizer_config/session1.dig"
•
Comments: A comments field. For example,
Comments = "This is a test for the diginfo functions"
•
TypeFile: The digitizer type file. For example,
TypeFile = "/digitizer_type/Altek.dtp"
•
ConfigFile: The digitizer configuration file. For example,
ConfigFile = "/digitizer_config/Altek.dcf"
Digitizer files
195
•
WarpControl Block: This contains information about the map
projection of the map you are digitizing from. For example,
WarpControl Begin
CoordinateSpace Begin
Datum = "AINABD70"
Projection= "CECASP"
CoordinateType= LL
Units = "METERS"
Rotation= 0:0:0.0
CoordinateSpace End
WarpControl End
Notes
•
The session (.dig) and config (.dcf) files are created via the
Digitizer Session dialog and the Digitizer Config dialog
respectively.
See the “Installing and configuring digitizers” chapter in
the ER Mapper Installation manual.
•
Digitizer modes
The type (.dtp) file is created by the user. There is no dialog to
do this, although this may change at a later date. Some sample
files are shipped with ER Mapper, so all that is needed is some
simple file editing.
ER Mapper requires the digitizer to transmit coordinates in ASCII
format.
ER Mapper supports two digitizing modes: Point mode and Line mode.
Both of these modes are activated by a “button down” type of event.
Some digitizers also have a Continuous mode where points are
transmitted continuously if the digitizer is on. These modes are NOT
supported - they are treated as Point mode and will most likely
prevent the mouse from being used (ER Mapper treats digitizer
events as being identical to mouse events over an image window).
In order to use Line mode, particular formats must be used.The
format MUST include a cursor status character indicating if the cursor
(or pen or button) is UP or DOWN. If there is no up or down status
character in the format then all digitizer events will be treated as
points.
These requirements can be interpreted as “You must have these
configuration switches set this way” and should not be a restriction
on the range of tablets that are supported.
ER Mapper does not accept digitizer input which uses <CR> as the
end of coordinate character.
196
Digitizer files
Hardcopy Processing and Filter programs
Images are sent to hardcopy devices by a program called ‘ermhe’.
This program can be run stand-alone, but is usually started from
within ER Mapper using the File menu Print... option. See the
Printing chapter in the ER Mapper User Guide. Because the
hardcopy utility is a separate program to ER Mapper, you can
continue using ER Mapper while an image is being sent to a hardcopy
device.
This chapter provides detailed information about the internal formats
used by the hardcopy engine and how to generate new hardcopy
filters. It is not necessary to read this section in order to print using
ER Mapper.
Hardcopy
processing stages
Internally the ER Mapper Hardcopy Engine generates hardcopy
output in three stages.
Create device
independent output
The first stage creates output for the device at the resolution of the
device. This output is always 24 bit RGB, regardless of the
capabilities of the output device. This first stage also merges the
vector overlays with the raster overlay components of the algorithm.
The result is that a true raster file is represented in absolute Color
values. This first stage is device independent.
Convert to device format
The data from the first stage is piped into the device dependent
stage of the hardcopy output. This piping process ensures that huge
amounts of disk storage are not required for an intermediate output
file.
In the device dependent second stage the RGB values per pixel are
converted into the hardcopy device specific format.
Send to device
The third stage involves piping the hardcopy device-specific format
to the hardcopy device. Output can be directed to any destination,
such as a real output device, or a magnetic tape unit or simply a file
on disk.
Output to a hardcopy device involves 3 programs: ermhe, a filter
program, and an output program. The filter and output programs
used are specified in the hardcopy control files which are stored in
the ‘hardcopy’ directory.
These three stages are shown diagrammatically below.
Hardcopy Processing and Filter programs
197
Vector 1..... .... Vector n
Raster 1...... .... Raster n
ALGORITHM
hardcopy
definition file
(.hc)
Hardcopy
engine
First Stage
Filter
program
Second Stage
Output
program
Third Stage
output device
Each scanline of the algorithm (processed image) is piped through
all stages so that the output of one stage becomes the input of the
next stage of hardcopy processing. This enables very large images
omages with much processing to be output to the hardcopy device
without creating huge temporary files.
Strip printing
If your hardcopy Mapperpper will automatically divide the output
image up into strips or pages that are no larger than the maximum
size allowed by the hardcopy device. Each of these strips or pages
are then processed individually.
The hardcopy
engine
The hardcopy engine gathers information about a hardcopy device
by looking for a file with suffix ‘.hc’ in the ERMAPPER\hardcopy
directped into the filter program.
198
Hardcopy Processing and Filter programs
The hardcopy engine
Output Format
The hardcopy engine uses an internal standard for processing of
hardcopy imagery, which is then converted to the output type
required. This internal format is:
Width(32 bit)
Line 1, Pixel 1
.
.
.
.
.
Line n, Pixel 1
Height (32 bit)
Line 1, Pixel 2........ Line 1, Pixel n
.
.
.
.
.
Line n, Pixel 2......... Line n, Pixel n
The hardcopy engine outputs one 4 byte integer (UINT32 or long
word) for each output pixel. The first two long words specify the
width and height of the raster file. The hardcopy engine guarantees
the width and height specified for a hardcopy image will never
exceed the maximum width and height allowed for the hardcopy
device selected. Each long word thereafter represents the hardcopy
image data. Line 1, Pixel 1 refers to the top left hand corner of the
image.
Each 32-bit value comprising the actual image contains a value from
0 - 255 for red, green and blue respectively, and a byte indicating
the height value for algorithms with a height layer. Assuming that
byte 4 is the most significant byte, the output integer can be
interpreted as follows:
Byte 4
Height
(if relevant)
Value
(0-1)
Byte 3
Byte 2
Red
Green
(0-255)
(0-255)
Byte 1
Blue
(0-255)
Filter Program
The filter program takes the data in hardcopy engine format and
converts it into the format required by the hardcopy device. The
output from the filter program is then piped into the output program.
Creating a Filter Program
(.c)
ER Mapper includes a library of many hardcopy device drivers. We
support as many output devices as possible and continually add new
devices, so please contact your distributor or Earth Resource
Mapping if your hardcopy device is not listed.
If you wish to create a Filter Program the interface is documented in
this section.
Hardcopy Processing and Filter programs
199
The filter takes as standard input the normal Hardcopy Engine
output, which consists of two UINT32 specifying output width and
height, followed by multiple UINT32’s, one per output pixel.
INPUT (UINT32)
FILTER (.C)
OUTPUT
(HARDCOPY
DEVICE FORMAT)
Filter program
Please consult your hardcopy device manual for details of the
hardcopy device output format your printer requires.
Standard output filters are provided for many popular printers.
Following is an example Filter Program (.c) for the Sharp JX730 color
ink jet printer (hetojx730.c).
/*****************************************************
***
** Copyright 1989 Earth Resource Mapping Pty Ltd.
** This document contains unpublished source code of
** Earth Resource Mapping Pty Ltd. This notice does
** not indicate any intention to publish the source
** code contained herein.
**
** FILE:
/home/erm/erm/src/erm/he/hetojx730/hetojx730.c
** CREATED:Mon Jul 23 19:28:40 WST 1990
** AUTHOR: Stuart Nixon
** PURPOSE:Hardcopy To sharp jx-730 filter program
(printer similar to tektronix)
** If the define variable FORM_FEED is true, then a form
feed is used,
** otherwise a 2" gap is printed at the end of a page...
**
** COMMENTS:
**
** 1. We use the Unidirectional mode, which is slow but
produces high
** quality prints.
**
** 2. This filter takes as standard input the normal
Hardcopy
** Engine output, which consists of two UINT32’s
specifying
** output width & height, and then multiple UINT32’s,
one per output pixel.
200
Hardcopy Processing and Filter programs
** The UINT32 consists of "xRGB", which "x" is currently
unused.
** This filter converts that output into something the
printer
** can understand.
**
** 3. This filter dithers output into a ordered 4x4
matrix in order to
** get enough colours.
**
** [01] 21/02/89 snsAdded formfeed at end of a strip
** [02] 23/07/90 snsCopied from ColourQuick &
supporting vectors
** [03] 02/08/90 snsMerged the 2" gap and the FORM
FEED versions
** [04] 03/08/90 snsNow doing compressed print mode
where possible
******************************************************
**/
#ifndef lint
static char *sccsident="@(#) %M%:%I% %D% Copyright
Earth Resource Mapping 1989";
#endif
#include <stdio.h>
#include "ERS.h"
/*
** CONSTANTS
*/
#define
#define
#define
#define
#define
DITHER4
VECTOR_FLAG_SHIFT24/* [04] */
RED_SHIFT16
GREEN_SHIFT8
BLUE_SHIFT0
#defineSTDIN0
#define STDOUT1
#define STDERR2
#define MAX_STRING 255
#define MAX_OUTPUT_WIDTH2448
#define START_GRAPHICS"\033G" /* use Control code group
"G" commands */
#define SEND_PLANE"\033I%c%03d"/* send image color line
*/
Hardcopy Processing and Filter programs
201
#define SEND_COMPRESSED"\033J%c"/* send compressed
image color line */
#define SEND_PRINT"\033A"/* End of this micro-line (4
planes) */
/* finish graphics mode [01] with a
2" gap or a FF */
#ifdef FORM_FEED
#define END_GRAPHICS "\014"
#else
#define END_GRAPHICS
"\012\012\012\012\012\012\012\012\012\012\012\012\012"
#endif
static char row_color[4][4] = {
{’0’, ’4’, ’8’, ’<’},/* Row 1, Black, Magenta,
Yellow, Cyan */
{’1’, ’5’, ’9’, ’=’},/* Row 2, Black, Magenta,
Yellow, Cyan */
{’2’, ’6’, ’:’, ’>’},/* Row 3, Black, Magenta,
Yellow, Cyan */
{’3’, ’7’, ’;’, ’?’}/* Row 4, Black, Magenta,
Yellow, Cyan */
};
/*
** GLOBAL VARIABLES
*/
static STRING progname;
static UINT32 output_width=0;
static UINT32 output_height=0;
static UINT32height_loop;
/*
** MAIN
*/
int main(argc,argv)
int argc;
char*argv[];
{
UINT32scanline[MAX_OUTPUT_WIDTH];
UINT8*readline;
int
len,to_read;
202
Hardcopy Processing and Filter programs
progname = argv[0];
/*
** Read header information from pipe (width &
height)
*/
{
UINT32 header[2];
if( read(STDIN, header, 8) != 8 ) {
fprintf(stderr,"%s: Unable to header info.\n",
progname,height_loop);
exit(1);
}
output_width = header[0];
output_height = header[1];
if( (output_width < 1) || (output_width >
MAX_OUTPUT_WIDTH)
|| (output_height < 1) ) {
fprintf(stderr,"%s: Bad width or height
info.\n",
progname,height_loop);
exit(2);
}
}
(void) start_output();
for( height_loop=0; height_loop<output_height;
height_loop++ ) {
/*
** read the next scan line. Because we are
reading from a pipe,
** we may have to do several reads to get the full
scan line
*/
to_read = output_width*4;
readline = (UINT8 *) scanline;
while( to_read ) {
len = read(STDIN, readline, to_read);
if(len < 1) break;
readline += len;
to_read -= len;
}
if( len <= 0) {
fprintf(stderr,"%s: Unable to read scan line
#%d.\n",
progname,height_loop);
(void) finish_output();
Hardcopy Processing and Filter programs
203
exit(3);
}
/*
** Process the scan line
*/
(void) process_scanline(scanline);
}
(void) finish_output();
exit(0);
/*NOTREACHED*/
}
/*
** output() - output some data
*/
int output(data,length)
char *data;
int length;
{
int wrote;
if( length>0 ) {
wrote=write(STDOUT,data,length);
if(wrote != length) {
fprintf(stderr,"%s: Tried to write %d bytes,
return=%d\n",
progname,length,wrote);
if( wrote<1 ){
perror("Write error");
}
return(1);
}
}
return(0);
}
/*
** start_output- sends init strings et al
*/
int start_output()
{
output(START_GRAPHICS,strlen(START_GRAPHICS));
}
/*
** finish_output- sends shutdown strings et al
*/
int finish_output()
{
output(SEND_PRINT,strlen(SEND_PRINT));
output(END_GRAPHICS,strlen(END_GRAPHICS));
204
Hardcopy Processing and Filter programs
}
/*
** process_scanline- converts and outputs the scan line
*/
#define CYAN_ON0x1
#define MAGENTA_ON0x2
#define YELLOW_ON0x4
/* these must match the row_color table */
#define BLACK_PLANE0
#define MAGENTA_PLANE1
#define YELLOW_PLANE2
#define CYAN_PLANE3
static UINT8 dither[DITHER][DITHER] = {
{
8, 136,
40,
168
},
{ 200,
72, 232, 104
},
{
56, 184,
24,
162
},
{ 248, 120, 216, 88
};
int process_scanline(scanline)
UINT32 *scanline;
{
static char current_row = 0;/* current row, from 0
to 3 */
char send_plane[MAX_STRING];
UINT32 pixel_loop,pixel;
UINT32 plane_loop;
UINT32 plane_byte;/* offset in plane_loop (bytes #)
*/
UINT32 plane_bit;/* offset in byte of plane (bit #)
*/
int vector_flag;
UINT8red_dither,green_dither,blue_dither;
UINT8turn_on,this_dither;
UINT8 color_plane[4][(MAX_OUTPUT_WIDTH+7)/8];
/* Black, Magenta, Yellow, Cyan
planes */
/*
** clear out the plane_buffer
*/
for( plane_loop=0; plane_loop < (output_width+7)/8;
plane_loop++ ) {
color_plane[0][plane_loop] =
Hardcopy Processing and Filter programs
205
color_plane[1][plane_loop] =
color_plane[2][plane_loop] =
color_plane[3][plane_loop] = 0;
}
/*
** output each pixel in the scan line
** We work out the Red, Green and Blue dither values
then
** change to Cyan, Magenta, Yellow to output to the
printer
*/
for( pixel_loop=0; pixel_loop<output_width;
pixel_loop++) {
pixel = scanline[pixel_loop];
/* get dither values. */
red_dither = (pixel >> RED_SHIFT)
& 0xff;
green_dither= (pixel >> GREEN_SHIFT) & 0xff;
blue_dither = (pixel >> BLUE_SHIFT) & 0xff;
vector_flag= (pixel >> VECTOR_FLAG_SHIFT) & 0x01;
/* [02] */
/*
** now convert dither patterns into colour
planes.
** We pull a trick here, by turning ON color
(e.g. YMC)
** if dither matrix is GREATER than value.
*/
if(vector_flag) this_dither = 129;
else this_dither = dither[pixel_loop %
DITHER][height_loop % DITHER];
this_dither = dither[pixel_loop %
DITHER][height_loop % DITHER];
if(red_dither < this_dither) turn_on = CYAN_ON;
else turn_on = 0;
if(green_dither < this_dither) turn_on |=
MAGENTA_ON;
if(blue_dither < this_dither) turn_on |=
YELLOW_ON;
plane_byte = pixel_loop>>3;
plane_bit = (7 - (pixel_loop & 0x7));
if(turn_on == (CYAN_ON | MAGENTA_ON | YELLOW_ON))
/* Black */
color_plane[BLACK_PLANE][plane_byte] |= (1 <<
plane_bit);
}
else {/* Must be white or some colour */
if(turn_on & CYAN_ON)
{
206
Hardcopy Processing and Filter programs
color_plane[CYAN_PLANE][plane_byte] |= (1
<< plane_bit);
if(turn_on & MAGENTA_ON)
color_plane[MAGENTA_PLANE][plane_byte] |=
(1 << plane_bit);
if(turn_on & YELLOW_ON)
color_plane[YELLOW_PLANE][plane_byte] |=
(1 << plane_bit);
}
}
/* [04] send image in RLL compressed mode */
for( plane_loop=0; plane_loop<4; plane_loop++ ) {
UINT8 out_plane[MAX_OUTPUT_WIDTH];/* could be
much smaller; /8? */
UINT8 *in_ptr = color_plane[plane_loop];
UINT8 *diff_ptr = color_plane[plane_loop];
int left = (output_width+7)/8;/* bytes left of
input */
int run_count =0;/* count of rll bytes */
int diff_count = 0;/* count of different bytes */
int outcount = 0;/* count of output bytes */
int notnull = 0;/* 1 if non all blank for this
line */
int loop255;
while(left--) {
if(*in_ptr) notnull = 1;/* well, at least we
have some data */
if(!left || (*in_ptr != in_ptr[1])) {
if(run_count && (left || notnull)) {
/* output the RLL data */
run_count += 1;/* include this value */
while(run_count > 255) {
out_plane[outcount++] = ’A’; /* t1:
rll flag */
out_plane[outcount++] = 0xff;
out_plane[outcount++] = *in_ptr;
run_count -= 255;
}
out_plane[outcount++] = ’A’; /* t1: rll
flag */
out_plane[outcount++] = (UINT8)
run_count;
out_plane[outcount++] = *in_ptr;
run_count = 0;
}
else {
Hardcopy Processing and Filter programs
207
if(diff_count==0) diff_ptr = in_ptr;
diff_count++;
}
}
if( !left || (*in_ptr == in_ptr[1])) {
if(diff_count) {
/* output the different data */
while(diff_count > 255) {
out_plane[outcount++] = ’B’; /* t2:
diff flag */
out_plane[outcount++] = 0xff;
/* a slow but portable loop - memcpy
would be faster */
for(loop255=0; loop255<255;
loop255++)
out_plane[outcount++] =
*diff_ptr++;
diff_count -= 255;
}
out_plane[outcount++] = ’B’; /* t2:
diff flag */
out_plane[outcount++] = (UINT8)
diff_count;
/* a slow but portable loop - memcpy
would be faster */
while(diff_count--)
out_plane[outcount++] = *diff_ptr++;
diff_count = 0;
}
run_count++;
}
in_ptr++;
}
if(outcount) {
sprintf(send_plane,SEND_COMPRESSED,
row_color[current_row][plane_loop]);
output(send_plane,strlen(send_plane));
out_plane[outcount++] = ’@’;/* t0: terminator
value */
output(out_plane,outcount);
}
}
/***[04] this was the old non-compressed mode data
for( plane_loop=0; plane_loop<4; plane_loop++ ) {
sprintf(send_plane,SEND_PLANE,
208
Hardcopy Processing and Filter programs
row_color[current_row][plane_loop],(output_width+7)/8)
;
output(send_plane,strlen(send_plane));
output(color_plane[plane_loop],(output_width+7)/8);
}
***/
current_row += 1;
if(current_row > 3) {
current_row = 0;
output(SEND_PRINT,strlen(SEND_PRINT));
}
}
The filter program takes the raw ermhe format and converts it to the
hardcopy device specific format. Within the filter program you must
allow for color compression, vector data, dithering and RLL and
chroma correction if your hardcopy device can handle these.
Color
compression
The ER Mapper hardcopy engine output format is always a 24 bit
RGB color image. Many hardcopy devices can only print a limited
number of colors, in which case the number of colors has to be
compressed from 224 (16.8 million colors).
By generating all ermhe output as 16 million color RGB and then
compressing the image to suit the physical hardware it is possible to
take advantage of whatever features the hardcopy device supports.
The compression routine in the above Sharp JX730 filter program
maintains the most significant color differences with a technique
known as ordered dithering.
Maintaining full RGB image quality until the last stage of output also
allows output to lesser devices such as Grey Scale or limited color
support and to devices using Hue Saturation Value instead of RGB.
Dithering
Dithering is one of the tasks of the filter program. A range of 16
million value colors is available on the display but on many hardcopy
output device these 16 million value colors are not possible. Without
dithering, most color printers have only 8 colors per pixel available,
made up of a mixture of cyan, magenta, yellow and black.
Dithering is used to overcome this limitation. Some hardcopy filter
programs provided with ER Mapper use an ordered dithering
algorithm which is included as an example in the Sharp JX730
hardcopy filter program earlier in this chapter. Ordered dithering
increases the color range and reduces artefacts otherwise created by
other dithering algorithms such as random dithering.
Hardcopy Processing and Filter programs
209
Dithering accommodates the continuous shade variations which are
necessary in remotely sensed images to produce less sharp
boundaries between the colors. This increased color range is at the
expense of spatial resolution when the image is changing color
density rapidly.
If vectors are dithered, the vectors on hardcopy look broken up and
blur into the background of the image. The filter program can check
if the pixel was a vector before rasterization, by checking the vector
flag. If the vector flag is set, then the filter program can decide not
to dither this pixel and choose one of the eight primary colors
instead.
One disadvantage of not dithering vectors is if you had asked for a
pink vector then you are probably going to get a red colored vector.
An advantage of dithering is that the vectors will be sharp and
distinguishable from the background raster image data.
Dithering is not mandatory, but is used in many of the supplied ER
Mapper hardcopy filter programs.
The ER Mapper hardcopy filter programs supplied use different
dithering algorithms such as Ordered Dithering, Error Diffusion,
Floyd Steinberg etc.
Hardcopy devices other than color printers, such as filmwriters do
not need to use dithering.
Image
compression
Because images generated can be very large, up to several hundred
megabytes, many hardcopy devices support compression techniques
such as run length limited (RLL). The filter program performs any
image compression required for the hardcopy. In the example Sharp
JX730 filter program the RLL compression technique is used.
Chroma
correction
If the printer documentation includes an algorithm for chroma
correction this can be implemented in the filter program.
Output Program
The output program takes the hardcopy device specific format and
directs it to a printer or file.
To direct the output to a local printer, use the following statement:
"he_writetofile :LPT1"
The output will go to the printer connected to local port LPT1.
You can also print to a file using the following statement:
"he_writetofile C:\documents\printfile.prn"
210
Hardcopy Processing and Filter programs
Subsampling/Sup
ersampling
Subsampling and supersampling are automatically performed by the
ermhe hardcopy engine. The output images are always generated at
the resolution of the hardcopy device regardless of the resolution of
the input images used in the algorithm. These means the quality of
the hardcopy is always as high as can be physically provided by the
hardcopy device.
Aspect ratio
The aspect ratio for the hardcopy is the same as for the algorithm on
screen. A 1:1 aspect ratio is enforced by default.
Hardcopy output
size
Hardcopy output size can be specified in three way: full resolution of
hardcopy device, measurement in inches or metres and scale.
To use the full resolution of the hardcopy device do not specify the
size or the scale of the hardcopy. The result is hardcopy which is one
page in width.
Secondly, you can specify how large you would like the output in
inches or metres. ER Mapper will automatically strip print if the size
is greater than that of the paper type in the hardcopy device.
In the third case, you can specify a scale. ER Mapper uses the cell
size of one of the images to scale the hardcopy produced.
In each method ER Mapper works out how large the image has to be
and calculates and prints as many strips as required.
You can use the ER Mapper Page Setup Wizard or Dialog to set
up the page sizes. Refer to the Page setup chapter in the ER
Mapper User Guide.
Color
The colors produced by the hardcopy device and those colors shown
on the display are essentially the same. However, hardcopy devices
use the subtractive color system whereas the display uses the
additive color space system. It is difficult to create hardcopy exactly
as it appears on the display because of how our eyes perceive the
different color spaces and the fact that the vectors are rasterized.
The ER Mapper display background is set to black and creates colors
by adding colored light to the black background. Small changes in
intensity in the dark shades are perceived more readily than in the
light shades. On the white background of the hardcopy device, ink is
added to a white background to produce various colors, that is they
are “subtracted” from white.
Hardcopy Processing and Filter programs
211
212
Hardcopy Processing and Filter programs
Importing using a command line
The most common way to import an image is to use the Import
commands on the ER Mapper Utilities menu. However, you can also
use command line options detailed in this chapter.
If you are to use the import utilities on a command line basis, rather
than the ER Mapper user interface, it is easiest to use them in the
directory where the imported file will be situated. Similarly,
‘mergeers’ and ‘invert’, should be used in the directory which
contains the input image files.
See mergeers and invert later in this chapter.
Before discussing the import programs some background
information on ER Mapper data storage method is required.
Raster and vector
image formats
The two data types used by ER Mapper are raster and vector. In each
case the data is stored in a file and has an appropriate ASCII header
file which describes the image more fully. The header file for raster
data has a file extension of ‘.ers’. The extension for vector header
files is ‘.erv’. An example raster image ‘my_data_set’ consists of
two files named ‘my_data_set’ and ‘my_data_set.ers’.
The data file itself is a binary file arranged as a Band Interleaved by
Line (BIL) image file. A BIL data file contains all cells for a single
image line as a sequential group of bands. To illustrate, if a BIL file
had two lines (L) of three cells (C) and contained two bands (B) the
sequence of values in the file would be:
•
L1B1C1, L1B1C2, L1B1C3,
•
L1B2C1, L1B2C2, L1B2C3,
•
L2B1C1, L2B1C2, L2B1C3,
•
L2B2C1, L2B3C2, L2B2C3
where L1B1C1 represents Line 1, Band 1, Cell 1 etc.
The data import utilities are used to translate raster or vector data
from one format to a format recognised by ER Mapper and to create
a header file for the data.
Importing using a command line
213
The ER Mapper import utilities include utilities for importing raster
header files from many of the sensing platforms (see Appendix A,
“Sensor platform characteristics”). These files provide sensor
characteristics and are used as a template by the import utilities.
Header information is copied from the sensor files and is combined
with the basic information extracted from the tape or specified at the
utility command prompt. In the case of raster files the basic
information includes the number of image lines, and the number of
cells per line. The resultant header file contains additional
information about the image which, although not essential for data
display, is highly desirable.
The sensor files may be found in the sensortype directory. Use the
supplied sensor files to assist you in creating your own additional
sensor files.
If you are experiencing difficulty importing text data files (e.g.
importascii, importgeoimage), check that the transfer of the
original raw text data file to the current machine was done using
a text mode of transfer. Transfer of text data files using a binary
mode of transfer instead of text mode may result in the file being
corrupted with control characters. This manifests itself when
copying text files from PCDOS/MSDOS to Unix.
Raster File Import
Switches
The import programs may be grouped into raster file import and
vector file import utilities. The raster import programs are discussed
in this section.
Vector import programs are discussed in the section “Vector
file import switches” later in this chapter.
The use of the group of raster import utilities are similar. They all
share common option switches. The syntax of the raster import
programs is as follows:
erm_run importprogram [switches] source_image
header_file.ers
When running command line programs you must prefix the
command with "erm_run". "erm_run" sets up the execution path so
that all the executable components can be found, and sets up any
environmental variables. This is done automatically when you use
the import utilities from inside ER Mapper.
The data importation is handled transparently by the import
program. The switches are:
•
214
-?: Displays a help message outlining the available switiches.
general usage message. For example,
Importing using a command line
erm_run importascii -?
would display the general usage and switches for the importascii
import program.
•
-t: Table of Contents. Shows details about the image without
importing the data. This switch allows the contents of a tape to
be examined before using the import program to actually import
the data.
•
-q: Query. Displays information about the file being imported and
prompts you for acceptance of the file before proceeding with the
import. This is useful when you are uncertain that the tape you
are using contains the correct file. If you accept the file data
importing continues normally.
•
-vVerbose. Displays messages during the importing. Progress
reports are displayed as each line is read and processed. If
additional -v switches are used additional information is
provided.
•
-l <line_range>: Specifies a sub section of the image lines to be
imported. For example,
-l20-300
will import lines 20 to 300 inclusive. The default setting for the
line range is all lines of the image.
When specifying lines with the -l switch the first line is zero, and
start and end lines are included, for example, to import the first
5 lines of an image,
-l0-4
•
-c <cell_range>: Specifies a sub section of the columns of the
image to be imported. It can be combined with the -l switch
above. For example,
-c100-6000
will import columns 100 to 6000 inclusive into the image. The
default range is all cells of the image.
When specifying cells with the -c switch the first cell is zero, and
start and end cells are included, for example, to import the first
5 cells of an image,
-c1-5
-b <band_range>: Specifies the bands to be imported. The bands
may be listed as band numbers separated by commas
(1,2,3,6,..) or groups of bands within a range inclusively (1-3) or
a combination of the two methods (1-3,7,9,11-14,..). The default
band selection is all bands.
When specifying a range of bands with the -b switch the first
band is band 1, and start and end bands are included.
Importing using a command line
215
•
-s <sensor_type>: The selection of a sensor type allows the
import utility to read the appropriate ‘.ers’ file for the sensor.
This contains a template for information such as wavelengths and
bandwidths for the sensor channels, cell dimensions etc. The
header file created during the importation will contain additional
information as was available from the sensor_type.ers file. If a
user specified sensor name starts with ‘.\’ or ‘\’ the path indicated
will be searched, otherwise ER Mapper will search the path
‘sensortype’ for the sensor_type.ers file.
•
-f <file_skip>: This allows files on the input device to be skipped
•
-x: Use the user interface instead of the command line interface.
in order to reach the file required for importation. This switch is
only supported when importing from devices such as magnetic
tape drives that are capable of skipping files. A non-rewind
device, such as /dev/nrs6250t0, must be used.
The import program user interface window will be displayed
prompting for information about the image, which would have
normally been specified using other switches on the command
line. For example,
$ erm_run importascii -x
will display the importascii user interface window.
The import program user interface is also accessible by choosing
Import Raster or Import Vector options from the ER Mapper
Utilities menu.
See the Importing and exporting data chapter in the ER
Mapper User Guide.
•
-P <name>: Specifies the projection of the image.
•
-D <name>: Specifies the datum of the image.
•
-r <value>: Specifies the rotation of the image from North, in
decimal degrees anticlockwise.
Importing Raster
File examples
Example 1
$ erm_run importascii -f3 -t /dev/rst17
will skip to the third file on a 6250 bits per inch (bpi) CCT and display
the details about the file. No data will be imported. Remember that
file skipping on a CCT requires a non-rewind device; in this case
/dev/rst17.
Example 2
216
$ erm_run importascii my_ascii_file my_image.ers
Importing using a command line
imports from disk rather than from a CCT. The source file
"my_ascii_file" is read and imported into ER Mapper format. The
specified destination file must have the ‘.ers’ file extension. ER
Mapper creates two files; the data file (‘my_image’) and the header
file (‘my_image.ers’).
Example 3
When using importbil you must specify the number of bands, number
of lines and number of cells in the image. The program will ask you
to enter these values. There is no standard header under BIL format,
because of the large number of tape formats used. For example, if
we wanted to import a file from a CCT device /dev/rs6250 a BIL
format file of 512 lines by 512 cells by 2 bands:
$ erm_run importbil /dev/nrs6250t0 bil.ers
The program would then prompt for the lines, cells and bands as
follows:
Please enter # of lines (rows) in input image : 512
#lines: 512
Please enter # of cells (columns) in input image : 512
#cells: 512
Please enter # of bands (channels) in input image : 2
#bands: 2
In the above example, the user has entered the number of lines, cells
and bands when prompted by the importbil program.
Example 4
$ erm_run importcct /dev/rst17 my_image.ers
Loads the first file on the non-rewind CCT device into the ER Mapper
image file ‘my_image’. The header file ‘my_image.ers’ will contain
a specification of the file size (lines, pixels, and bands). Note that the
importcct program will only accept a tape drive as the data source.
Unlike importcct, the other raster import programs can accept data
from other accessible devices; hard disk and optical disk storage and
files located on other computers (if ER Mapper is connected to a
network).
Example 5
Copy a small subsection and single band of a DISIMP format file on
the 1/4 inch cartridge tape device /dev/rst8 to an ER Mapper raster
file ‘postage_stamp’; ‘postage_stamp.ers’ will be created during
the import. The first file on the tape will be copied.
$ erm_run importdisimp -l20-50 -c400-430 -b2 /dev/rst8
postage_stamp.ers
Example 6
Subsection a square image (1024 lines and 1024 cells) of all bands
from the disk file ‘dolaimage’ into the ER Mapper file ‘test_zone’.
Display the file details and request confirmation that the file is the
correct one before copying the data.
$ erm_run importdola -l1-1024 -c101-1124 -q dolaimage
test_zone.ers
Importing using a command line
217
Example 7 (importusgs)
Import the disk file ‘sample_data’ in USGS format into the ER
Mapper file ‘my_data.ers’. ER Mapper will ask if the requested file
is the correct one (-q) and will print a progress report as each line is
copied (-v).
$ erm_run importusgs -q -v sample_data my_data.ers
Vector File Import
Switches
The vector import utilities are used in a similar way to the raster
image data utilities discussed above. The type of data provided by
vector files makes several of the option switches used for raster files
inappropriate.
The syntax of the vector import programs is as follows:
erm_run importprogram [switches] source_image
header_file.erv
The data importation is handled transparently by the import
program. The switches are:
•
-?: Displays a help message, outlining the switches.
erm_run importas2482 -?
would display the general usage and switches for the
importa2482 import program.
218
•
-t: Shows a Table of Contents with details about the image being
processed by the import program. It examines the image but
does not actually import the data. Used to examine a tape before
using the import program to actually import the data.
•
-q: Query. Displays information about the file being imported and
prompts you for acceptance of the file before proceeding with the
import. This is useful when you are uncertain that the tape you
are using contains the correct file. If you accept the file data
importation continues normally.
•
-v: Verbose. Displays progress reports as each line is read and
processed. If additional -v switches are used additional
information is provided.
•
-f <file_skip>: Skips files in order to reach the file required for
importation. This switch is only supported when importing from
devices such as magnetic tape drives that are capable of skipping
files. A non-rewind device, such as /dev/nrs6250t0, must be
used.
•
-xAllows the user interface to be used instead of the command
line interface. The import program user interface window will be
displayed, prompting for information about the image which
would have normally been specified using other switches on the
command line. For example,
Importing using a command line
erm_run importas2482 -x
will display the importascii user interface window.
The import program user interface is also accessible by choosing
import options from the ER Mapper Utilities menu.
See the Importing and exporting data chapter in the ER
Mapper User Guide.
•
-P <name>: Specifies the projection of the image.
•
-D <name>: Specifies the datum of the image.
•
-r <name>: Specifies the rotation of the image from true North,
in decimal degrees, counterclockwise.
The switches listed above are all common to the vector data
import utilities. The vector import formats currently supported
are listed in the Supported import formats chapter in the ER
Mapper User Guide.
Importing Vector
File examples
Example 1
$ ermrun importas2482 /dev/nrs6250t0 mainroads.erv
Imports the AS2482 format vector file on the half inch magnetic tape
into the ER Mapper vector file ‘mainroads’. The vector header file
‘mainroads.erv’ will be created automatically.
Example 2
$ erm_run importgeoimage -f3 -t /dev/rst17
Shows details for the GeoImage format vector file which is the third
file on the half inch magnetic tape /dev/rst17. The file is not
imported.
Invert
The ‘Invert’ utility is used to change the orientation of either an .ers
raster file or a virtual dataset. It can be run from the command line
using the switches described below.
erm_invert [-vhbwx] input_image output_image
For example to invert an image from left to right and top to bottom:
invert -b input_image inverted_image
The inversion process treats the data as raw data. It will not
invert your coordinate system.
Importing using a command line
219
The switches are described below. You can use the -x flag to run the
program with the graphical interface, in the same way as though you
had chosen the Invert a Raster or Virtual Dataset option from the
Utilities / File Maintenance /Datasets menu. If you don’t use the
-x flag, you must use one of the -vhb flags and give the input and
output image names.
•
-v: Inverts the data around the vertical line of symmetry.
•
-h: Inverts around the horizontal line of symmetry.
•
-b: Inverts around the horizontal and vertical line of symmetry.
•
-w: Overwrites an existing output file.
•
-x: Runs the program using the graphical user interface.
•
input_image: The input image can either be a full directory path
or a path relative to the current path.
•
output_image: The output image name needs to include the
directory path, otherwise it will be output into the same directory
from which you ran erm_invert.
Some of these facilities are also available on the ER Mapper
main dialog box. Select File Maintenance / Datasets from the
Utilities menu.
220
Importing using a command line
Utilities
There are a number of utility programs that are used in various
places by ER Mapper. They are included here because you may find
them useful to incorporate in your own dynamic links options.
Coordinate
conversion
togeo
This command line utility prompts the user for rectangular (EN)
coordinates of a point in space and outputs the corresponding LL
coordinates based on the projection and datum entered by the user.
All information needed by the utility is acquired during the program
run and hence, no arguments are required on the command-line.
fromgeo
This utility is the inverse of "togeo". It takes the LL coordinates of a
point and outputs the corresponding rectangular (i.e. EN)
coordinates based on the projection and datum entered. As with
"togeo" all information needed by the utility is acquired during the
program run itself and not from the command-line.
gdt_conv
Similar to the above conversion routines. It prompts the user to
enter an input projection/datum pair and an output
projection/datum pair than a 3-D coordinate. The utility then
converts the entered coordinate to the corresponding coordinate of
the point in the new (i.e. output) projection/datum coordinate space.
Tape utilities
erm_tapeutil
This utility mimics the behavior of the UNIX system command "mt".
It allows the user to perform basic tape operations like rewinding
tapes, skipping files on a tape, checking for the current status of a
given tape device etc.
•
Syntax: erm_tapeutil -f <tape_device> <command_to_issue>
•
<tape_device>: The name of the tape device for which the
•
<command_to_issue>: One of the following:
•
bof: Finds the beginning of the current file on the tape
•
dump [n]: Reads a record from the file and dump [n] characters.
command is intended
The default number of characters read equals the size of the
record to be read.
•
Utilities
fsf [n]: Skips past "n" files on the tape.
221
•
tape_struct
dump_cct
tape2disk
disk2tape
rew: Rewinds the tape to the beginning.
This utility creates a report on the structure of data provided on tape
and it typically used for determining the exact origin/format of a
given tape-based image.
•
Syntax: tape_struct <tape_device>
•
<tape_device>: The name of the tape device.
This utility provides the same functionality as that provided by
"tape_struct" above.
•
Syntax: dump_cct <tape_device>
•
<tape_device>: The name of the tape device.
This command line utility reads all files from tape into the specified
disk file maintaining the original structure of the data (i.e. with EOF
markers and so on).
•
Syntax: tape2disk <tape_device> <output_disk_file>
•
<tape_device>: The name of the tape device.
•
<output_disk_file>: The name of the target disk file.
This utility performs the inverse operation to the above. It takes a
disk file whose structure is identical to that of the original data on
tape and recreates the structure on the tape device specified as the
second argument to the program.
•
Syntax: disk2tape <disk_file_name> <output_tape_device>
•
<disk_file_name>: The name of the disk file containing the data.
•
<output_tape_device>: The name of the target tape device.
The above two utilities are typically used together for copying
tapes; e.g. creating a low-density copy of a high-density tape.
Image file
compression
ecw_compress
222
Use this command to compress an image file size. As this is an ER
Mapper executable, you need to ensure that the ER Mapper
environment variables are correctly set up; the easiest way to do this
is to use the "erm_run" command. "erm_run" sets up the execution
path so that all the executable components can be found, and sets
up any environmental variables.
Utilities
Syntax:
erw_compress infile [-show] [-o outfile] [-c
compression_ratio] [-g | -rgb | -multi]
•
-show: report the expected output size only, and not compress
•
-nowait: after compression, do not report a message dialog and
•
-g: compress to a single band UINT8 greyscale output file.
•
-rgb: compress to a RGB file optimized for color imagery
compression.
•
-multi: will compress to a multi-band image (only 3 band, UINT8
wait for user
format, supported at present)
Example:
C:\Program Files\ERDAS\ERDAS ER Mapper
7.2\bin\win32\erm_run ecw_compress input.ers -o
output.ers -rgb -c 20
ecw_compress_gui
Use this system command in your ER Mapper wizard batch scripts to
interface to the compression engine.
Syntax:
erw_compress_gui infile [-show] [-o outfile] [-c
compression_ratio] [-g | -rgb | -multi]
•
-show: report the expected output size only, and not compress
•
-nowait: after compression, do not report a message dialog and
•
-g: compress to a single band UINT8 greyscale output file.
•
-rgb: compress to a RGB file optimized for color imagery
compression.
•
-multi: will compress to a multi-band image (only 3 band, UINT8
wait for user
format, supported at present)
Example:
$compress_command = "ecw_compress_gui \"" + $FromFile +
"\" -o \"" + $OutputFile + "\" -c " + $TheRatio + " " +
$compress_format
system $compress_command
Utilities
223
224
Utilities
Batch scripting and wizards
This chapter describes how you use the ER Mapper scripting
language to create batch scripts. These batch scripts can range from
a list of operations which can be run from a single command line to
dialog boxes and wizards with which users can interact.
You can connect these batch operations to the menus and toolbars
on the ER Mapper user interface.
The scripting language includes powerful commands for creating
wizards. ER Mapper is supplied with a number of pre-designed
wizards accessible via the menus and toolbars. You can use the
scripting language to customize these or create your own. Refer to
the “Wizard scripts” section for information on creating wizards.
You can design wizards so that they “remember” settings or
values entered. See “Using preferences to remember
settings”.
Batch script
documentation
Additional documentation on batch scripting may be found in the
following chapters:
The “Scripting language” chapter covers the structure and
composition of the scripting language. It describes data input and
output methods and gives an overview of the actions that can be
performed on the different ER Mapper objects. It also describes the
structure of the commands.
The “Scripting reference” chapter lists and describes all the
Keywords, Operators, Variables and Commands used by the
scripting language. The Command descriptions include their syntax
and examples of their use. The chapter contains the following
sections:
Section
Description
“Operators”
Suite of standard operators
“Mathematical functions”
Mathematical functions
“Variables”
Variable types and their allowed values
“Page size options”
Standard page sizes that can be used
“Keywords”
List of keywords
“Flow control”
Flow control components like labels and
‘goto’ commands.
“Including files”
How to include library batch files
Batch scripting and wizards
225
“Error reporting”
Reporting errors
“Script commands - alphabetical listing
List of all the script commands in
alphabetical order.
Creating a batch
script
The steps involved in creating your own batch script are as follows:
1. Design the layout of dialog boxes if they are being used.
Decide on the appearance of dialog boxes, keeping in mind current
conventions. We suggest that you maintain the look and feel of the
existing ER Mapper dialog boxes. If you are designing a wizard, draw
a flow diagram showing the sequence of the dialog boxes that will be
displayed depending on the user inputs.
2. Use a text editor to create the script.
You can use any text editor to create the script. It may be easier to
use the Utilities / Batch Scripts / Create a Batch Script menu
option. This will save the new batch script in the \batch directory and
open it in a text editor.
Browse through the ‘batch\lib’ directory to see if there are any library
scripts you can include in your script.
It might also be easier to edit an existing batch script using the
Utilities / Batch Scripts / Edit a Batch Script menu option, and
then save it with a new name.
Refer to the “Scripting reference” chapter for information on
the syntax of the commands.
3. If required, edit the menu (.erm) and toolbar (.bar) files to make the
batch program accessible via the menus and/or toolbars.
Use either the Utilities / Toolbars / Create a Toolbar or the
Utilities / Toolbars / Edit a Toolbar menu option depending on
whether you want to create a new toolbar or to add an icon to an
existing toolbar.
Use the Utilities / User Menu / Edit a File menu option to add a
new entry to the ER Mapper menus.
Refer to the “Menu and toolbar files (.erm) and (.bar)”
chapter for information editing menu and toolbar files.
Getting started
226
The following procedure describes how you would;
•
Create a simple “Hello World” batch script
•
Insert a menu option to run your script in the Process menu.
Batch scripting and wizards
•
Add a button to run your script to the Standard toolbar.
Create a simple batch script
1. Select Batch Scripts / Edit a Batch Script from the Utilities
Menu.
The Batch Engine Requester dialog box opens.
2. Enter “hello_world.erb” for the name of your new batch file, and click
on the OK button.
ER Mapper opens the text editor specified by the ERMEDIT
environment variable. If you have not set this for a specific editor, it
will default to NotePad.
3. Enter the following text in the editor window. Save the file and exit
the editor.
4. Click on the Close button on the Batch Engine Output window if it
is open.
Insert a menu option entry
1. Open the file config\processmenu.erm in your text editor.
2. Add the following lines to the processmenu.erm file:
3. Save the modified processmenu.erm file.
Add a button to the toolbar
You will first need to create a 24-bit 16 x 16 pixel tiff file for the
button and copy it into the ‘icons’ directory.
Batch scripting and wizards
227
1. Using any raster graphics application such as Corel PhotoPaint or
PaintShopPro, create an appropriate Image. Save it as a 16x16 pixel
tiff (.tif) file, Hello.tif, in the ‘icons’ directory.
You can also use ER Mapper to save an image as 16x16 pixel tiff
file.
1. Open the file config\Standard.bar in your text editor.
2. Add the following lines to the Standard.bar file.
3. Save the modified Standard.bar file.
Run the batch script
1. Exit ER Mapper and restart it.
The new toolbar button should now be visible on the Standard
toolbar.
2. Move your mouse pointer over the new button. Check that “Hello
World” is displayed as a tooltip.
3. Click on the “Hello World” button to run the script.
The Batch Engine Output dialog should open displaying the words
“Hello World”.
4. Click on the Close button to close the Batch Engine Output dialog.
5. Select the Process menu and note that a Hello World option has
been added.
6. Select Hello World from the Process menu and check that the
batch script runs as before.
Run the batch script from a command file
It is also possible to run a batch program from a command line
outside of ER Mapper using the ermapper -b command; e.g:
ermapper -b batch_script
228
Batch scripting and wizards
where batch_script is the name of your batch program.
To run your script from a command line you must add the following
line to the script:
exit
n
Where n is the exit code returned from ER Mapper.
•
n = 0: exits the script and leaves ER Mapper open.
•
n = >0: exits the script and closes ER Mapper.
1. Open an MS-DOS Prompt window.
2. In the MS_DOS Prompt window, change to the ‘batch’ directory.
3. Enter the following command:
ermapper -b hello_world
This should run the script as before.
You could also have run the script from any directory using the full
path name, e.g.:
ermapper -b “c:\Program Files\ERDAS\ERDAS ER Mapper
7.2\batch\hello_world”
Make sure that your PC PATH environment is set up correctly so
that it can locate the ermapper.exe file in the ‘bin\win32’
directory.
Example display and
geolinking script
Now that we have managed to write and execute a “Hello World”
script we can try something more challenging.
This example batch script will perform the following tasks
•
Batch scripting and wizards
Open a dialog box which allows the user to choose or enter the
filenames of two algorithms to be displayed. The user is also
given the option of having the algorithm display windows
SCREEN geolinked.
229
•
Display the two algorithms in two separate windows, one large
and one small. The large window will be positioned in the top left
corner of the screen, with the small window just below it.
1. Select Batch Scripts / Create a Batch Script from the Utilities
menu.
2. Enter ‘Display_Geolink.erb’ in the Script name: field of the Choose
a name for the new script dialog.
230
Batch scripting and wizards
3. Enter the following script in the text editor page that opens:
Script
Comments
ask begin
Start of dialog box. Must have a
corresponding ‘ask end’ later.
title "Geolink display"
Title of the dialog box
$count = 0
Initialize the loop by setting the count to
0.
increment:
Label for loop re-iteration
say "Please enter the file
name"
Optional text in the dialog box.
$myfile[$count] = ""
Initializes the $myfile[] variable
ask file "Algorithm:" ".alg"
$myfile[$count]
Add Algorithm field to dialog box for
user to enter an algorithm filename with
a .alg extension. The field includes a
button to open the ER Mapper file
chooser. The filename is stored in the
$myfile[} variable.
$count = $count + 1
Increment the count
if ($count == 1) then goto
increment
Repeat the loop until condition is
satisfied. (In this case the loop will be
repeated once)
$link = 0
Initialize the yesno $link variable to 0
(No).
say "Do you want the images
geolinked to screen?"
Optional text in the dialog box.
ask yesno "Geolink:" $link
Add selection box for users to check it
they want the windows to be geolinked
and thus set $link to 1 (Yes).
ask end
End of dialog box.
$win[0] = new window 0 0 600
600
Add new 600 x 600 pixel image window
situated in the top left corner of the
screen (0 0). Set $win[0] variable to
point to this window.
$win[1] = new window 0 600 250
250
Add new 250 x 250 pixel image window
situated 600 pixels vertically below the
top left corner of the screen (0 600). Set
$win[1] variable to point to this window.
$count = 0
Initialize the loop by setting the count to
0.
increase:
Label for loop re-iteration.
select $win[$count]
Select $win[$count] to be the active
window.
Batch scripting and wizards
231
Script
Comments
load algorithm $myfile[$count]
Load the algorithm whose filename is
stored in $myfile[$count] into the batch
engine.
copy algorithm to window
Copy the loaded algorithm from the
batch engine to the active window.
if ($link != “yes”) then goto
no_link
Check if the user selected Yes for
geolinking the windows ($link = “yes”).
If not then skip the next line and go to
the no-link label.
set window geolink mode to
screen
Set the currently active window to
geolink SCREEN mode.
no_link:
Label for ‘if ..then goto..’ command.
$count = $count +1
Increment the counter for the loop.
if ($count == 1) then goto
increase
Repeat the loop if the condition is met.
end_script
End of script label.
4. Save the Display_Geolink script and exit the text editor.
5. Add the Display_Geolink menu option to the Process menu by
editing the processmenu.erm file. See “Insert a menu option
entry” above for an example of doing this.
6. Add a Display_Geolink button to the Standard toolbar by editing
the Standard.bar file. “Insert a menu option entry” above for an
example on doing this.
7. Run the script by either selecting Display_Geolink from the
Process menu, or by clicking on the Display_Geolink button.
To try this script, we suggest that you use the
‘\examples\Data_Types\Landsat_TM\RGB_321.alg’ in the large
window, and
‘examples\Data_Types\SPOT_Panchromatic\greyscale.alg’ in the
small window. Run the script with and without selecting the
geolinking option. When select the geolinking option, move the small
window over the large widow to view the results. The expected result
is shown below:
232
Batch scripting and wizards
Wizard scripts
The ER Mapper batch script language enables you to create
interactive guided wizard scripts. Wizards are made up of one or
(usually) more pages that step a user through a task. They guide the
user to making choices, providing any necessary information and
suggesting appropriate choices when possible. They are especially
useful for complex tasks or tasks requiring a number of steps.
For information about general batch script commands see the
“Scripting language” chapter.
Batch scripting and wizards
233
Example wizard script
You can insert batch commands to create a wizard interface into any
batch script. The structure of the script will vary depending on the
nature of the task but will generally be made up of the following
sections.
•
a setup section in which variables and default values are set up
and any necessary information is copied from the current
algorithm or elsewhere
•
a wizard section in which the layout and contents of the wizard
pages are specified, as well as where to store any user input and
any procedures to be run as a consequence of the user’s choices
•
an outcome section in which the procedures to be carried out as
a consequence of the user’s choices in the wizard are specified.
This chapter is concerned with the wizard section.
The simple wizard script ‘Image_View.erb’ is shown next.
# Script:
Image_View.erb
# Summary: Wizard to view an image
# Details: Wizard wrapper around Create_RGB.erb
# Creates an RGB algorithm from the current window
algorithm.
# It uses the following strategy:
#1)Look for any valid RGB layers.If any are present,
turn them
# on, run & exit.
234
Batch scripting and wizards
#2) Check the current layer - if it has a dataset it
uses it to
# create the algorithm (simply turning the layer on if
it’s a
# pseudocolor layer).
#3)Look for an active pseudocolor layer. If one is
found, use
# its dataset to create the RGB algorithm.
#4)Look for any raster layer with a valid dataset. Use
it to
# create the new algorithm.
#5) At this point there is no valid dataset, so ask for
one &
# use it to create the RGB algorithm.
include "lib/BE_Startup.erb"
if current window then goto window_ok
new window
window_ok:
copy algorithm from window
# Set the layer to it
$LIB_lay1 = current layer
$LIB_alg1 = current algorithm
$LIB_tra1 = last transform
$image_filename = get layer dataset
----------------------------------------------------------------------------------Wizard pages are defined using the following format.
----------------------------------------------------------------------------------include "lib/BE_Startup.erb"#wizard set up
WizardPage1:
#label for page 1
WizardPage begin "WizardName"#title for first page
title "Page1Name" #if a new wizard
container begin "Image"
container information#usually image info
...
#on first page
container end
container begin "DataEntry"
container information
...
container end
container begin "PageControls"#control buttons
ask action "< Back"
ask action "Next >" goto WizardPage2
ask action "Cancel" close
Batch scripting and wizards
235
container end
WizardPage end
WizardPage2:
#label for page 2
WizardPage begin
#no title
title "Page2Name"
container begin "container1name"
container information
...
container end
container begin "container2name"
container information
...
container end
container begin "container3name"
container information
...
container end
WizardPage end
----------------------------------------------------------------------------------The layout of wizard
pages
Title Bar
Graphic
Information
Container
User Input Container
Navigation Container
236
•
Wizard pages are made up of a number of different areas. The
exact design of wizard pages varies but generally the pages
consist of
•
an information container at the left which usually has a graphic
image.
•
a user input container to the right
•
navigation container with buttons at the bottom
•
graphics can be used if they help illustrate the process and are
easily recognized as being non-interactive
Batch scripting and wizards
•
Scroll bars appear if the container sizes would otherwise cause
the dialog to be larger than 440 pixels wide by 320 pixels high.
•
The wizard does not check values that are entered by the users—
it is up to your batch script to do this.
Wizard page
Each wizard page is set up by WizardPage Block, defined between a
‘WizardPage begin’ and ‘WizardPage end’ statement. You need as
many WizardPage blocks as there are pages in the wizard. Each of
the areas ‘contains’ different things and is therefore known as a
‘container’. The size and contents of each container must be
specified. An example wizard block is:
WizardPage begin "WizardName"#title for first page
title "Page1Name" #if a new wizard
container begin "Image"
container information
#usually image info
...
#on first page
container end
container begin "PageControls"
#control buttons
ask action "< Back"
ask action "Next >" goto label1
ask action "Cancel" close goto label2
container end
wizard close
WizardPage end
Container
A container block defines the size, contents and layout of a single
‘container’ or ‘pane’ in a wizard page. Any number of containers can
be defined though realistically there will be only two or three per
page. For example,
container begin "con2"
container height_pct 20
container below "con1"
ask action "< Back"
ask action "Next >" goto wizard_page2
ask action "Cancel" close goto wizard_page2
container end
Batch scripting and wizards
237
Navigation buttons container
The last container on any page should contain the standard
navigation buttons.
container begin "con2"
container height_pct 12
container below "con1"
ask action "< Back"
ask action "Next >" goto wizard_page2
ask action "Finish" goto check_parameters_and_close
ask action "Cancel" close goto wizard_close
container end
The buttons should be programmed to work in the following way:
•
<Back: Returns to the previous page. It should be greyed out on
the first page. (This is achieved by an ask action command with
no specified GoTo Label; as per the "Back" button in the example
above). When the user presses the Back button they should be
presented with any choices they have made up to that point
rather than the original defaults. Therefore defaults should be set
up before the first Wizard Block.
•
Next>: Moves to the next page in the sequence, maintaining
whatever settings the user provides in previous pages. This is
greyed out on the last page.
•
Finish: Applies the settings defined in the wizard (either default
or input by the user) to ER Mapper and completes the task. The
finish button must appear on the last page and should be
included at any point that the wizard can complete the task (even
the front page if there are reasonable defaults).
Cancel: Discards any settings specified in the wizard, terminates the
process, and closes the wizard window. The Cancel button is always
the right most button.
A single page wizard has only a Finish and a Cancel button.
For a consistent look multi-page wizards should have Next and Back
buttons on all pages. However, the Next button should be replaced
by a Finish button on the last page, and the Back button should be
greyed out on the first page.
Ask and Show commands
All the "Ask", "Say" and "Title" commands, such as
Ask Yesno "Show Contours:"
$contours_yn
work within a Wizard block. However, the ‘Ok’, ‘Cancel’ and ‘Help’
buttons which are automatically added to Ask Blocks do not appear
in Wizard blocks.
238
Batch scripting and wizards
In addition, a number of Ask commands are designed especially for
specifying input into wizards. These are documented in “Dialog box
input fields” below. They include, for example, ‘Ask Action’ which
draws the navigation buttons on the bottom of the wizard page.
Show Image "Filename"
Shows the image TIF file in the container, following the same rules
that other Ask/Show items do. The image is shown at its true size,
not fitted to the container size. The image files default directory is
‘icons’.
General guidelines for
wizard pages
Batch scripting and wizards
•
Wizards should have Windows XP look and feel.
•
Pages should flow linearly through a series of steps. It is possible
to jump from one wizard to another but this should be avoided
as it will confuse the user. The user should not have to use any
functions outside of the wizard to complete a task.
•
Wizard pages should be easy to understand without having to
read them very carefully. It is better to use more simple pages
than fewer complex pages.
•
If it isn’t obvious, the last page should give the user information
about how to proceed when the wizard is finished.
•
Wizards don’t automatically progress to the next page. the user
may have neglected to provide all necessary information, in
which case a ‘Wizard Error’ will be reported. The wizard does not
proceed until the appropriate field is filled in.
•
Use a conversational writing style, with words like you’ and
‘your’, contractions and short, common words.
•
Ask users what they would like to do rather than telling them
what to do. Thus, use ‘which option do you want…’ or ‘would you
like…’ instead of ‘choose a layout’.
•
Avoid using technical terminology that may be confusing to a
novice user.
•
Use as few words as possible.
•
Keep the writing clear, concise and simple, but don't be
condescending.
•
It is quite possible (as with ask forms) to decide under program
control if containers or ask/say commands are to be added to a
wizard form. This makes it quite powerful.
•
If a label name of a ‘labels_left’ container item is too long, part
of it will not be displayed. If this occurs, either change to
‘labels_above’ or shorten the label.
239
•
Example wizard
It is not possible to have wizard dialogs which close automatically
when, for example, a process is completed. The containers must
have a control (Save, Close, Finish etc.) that explicitily closes
the dialog.
Below is an example of a wizard script showing the created wizard
pages.This and other examples can be found in the ‘batch’ directory.
#
# Script:
3D_Wizard.erb
#
# Summary: Wizard to create a standard single surface
3D algorithm
#
# Details: Ask for a pseudo or RGB alg, choose the
datasets,
#
create an algorithm, copy it to the window and
#
set the view mode to 3D. Simple!
#
include "lib/BE_Startup.erb"
$yesno_Pseudocolor = "1"
$yesno_RGB = "0"
$listmenu["0"] = "Psuedo Color"
$listmenu["1"] = "RGB"
$list_choice = $listmenu["0"]
$RasterDataset = ""
$HeightDataset = ""
$lut = "greyscale"
######################################################
############
240
Batch scripting and wizards
wizard_page_1:
Wizard begin "3D Algorithm Wizard"
title "3D Algorithm Wizard"
container begin "Mode"
container items labels_left
container right "Image"
say "This Wizard will help you to create a"
say "single surface, 3D algorithm."
say ""
say "You need a raster dataset and a height"
say "dataset over the same area."
say ""
say "Select the type of 3D algorithm you want"
say "to produce:"
ask listmenu_exclusive "" $listmenu $list_choice
container end
container begin "PageControls"
container height_pct 12
container below "Mode"
container items horizontal right justify
ask action "< Back"
ask action "Next >" goto CheckPseudo_or_RGB
ask action "Cancel" close goto WizardCancel
container end
container begin "Image"
container width_pixels 131
container height_pixels 280
container left "Mode"
container above "PageControls"
show image "standard_icons/Wizards/3D_wiz"
container end
Wizard end
CheckPseudo_or_RGB:
if ($list_choice == "RGB") then goto
wizard_page_2_rgb
goto wizard_page_2_pseudo
######################################################
############
Batch scripting and wizards
241
wizard_page_2_rgb:
Wizard begin "3D Algorithm Wizard"
title "3D Algorithm Wizard"
container begin "InputDatasets"
container items labels_above
container right "Image2"
say "Select the datasets to use in this"
say "algorithm and the band to use for the"
say "height layer:"
say ""
say "The raster dataset must have at least 3"
say "bands to produce a 321-RGB algorithm"
ask file "Raster dataset: "
".ers"
$RasterDataset
ask file "Height dataset: " ".ers" $HeightDataset
say ""
ask bandmenu "Band for height data:"
$HeightDataset
$bandmenu
container end
container begin "Image2"
container width_pixels 131
container height_pixels 280
container above "PageControls2"
show image "standard_icons/Wizards/3D_wiz"
container end
242
Batch scripting and wizards
container begin "PageControls2"
container height_pct 12
container below "InputDatasets"
container items horizontal right justify
ask action "< Back" goto wizard_page_1
ask action "Finish" goto WizardFinish
ask action "Cancel" close goto WizardCancel
container end
Wizard end
######################################################
############
wizard_page_2_pseudo:
Wizard begin "3D Algorithm Wizard"
title "3D Algorithm Wizard"
container begin "InputDatasets"
container items labels_above
container right "Image2"
say "Select the datasets to use in this"
say "algorithm and the band to use for the"
say "height layer:"
say ""
ask file "Raster dataset: "
".ers"
$RasterDataset
ask lutmenu "Color table:" $lut
say ""
ask file "Height dataset: " ".ers" $HeightDataset
ask bandmenu "Band for height data:"
$HeightDataset $bandmenu
container end
Batch scripting and wizards
243
container begin "Image2"
container width_pixels 131
container height_pixels 280
container above "PageControls2"
show image "standard_icons/Wizards/3D_wiz"
container end
container begin "PageControls2"
container height_pct 12
container below "InputDatasets"
container items horizontal right justify
ask action "< Back" goto wizard_page_1
ask action "Finish" goto WizardFinish
ask action "Cancel" close goto WizardCancel
container end
Wizard end
######################################################
############
Warn1:
say warning "You must choose a Raster dataset"
if ($list_choice == "RGB") then goto
wizard_page_2_rgb
goto wizard_page_2_pseudo
Warn2:
say warning "You must choose a Height dataset"
if ($list_choice == "RGB") then goto
wizard_page_2_rgb
goto wizard_page_2_pseudo
WizardFinish:
if ($RasterDataset == "") then goto Warn1
if ($HeightDataset == "") then goto Warn2
wizard close
if ($list_choice == "RGB") then goto DoRGB
goto DoPseudo
######################################################
#########
DoPseudo:
$alg = new algorithm
set $alg description "Pseudo Color 3D"
set $alg mode pseudo
set $alg lut to $lut
$layer1 = first layer
set $layer1 description "Raster"
set $layer1 dataset to $RasterDataset
$lasttran= last transform
set $lasttran limits to actual
add height layer
$layer2 = current layer
set $layer2 description "Height"
set $layer2 dataset to $HeightDataset
set $alg view mode to perspective
244
Batch scripting and wizards
new window
copy algorithm to window
go window
goto FinishUp
######################################################
#########
DoRGB:
$alg = new algorithm
set $alg description "RGB 3D"
set $alg mode rgb
$layer1 = first layer
set $layer1 type red
set $layer1 description "Red"
set $layer1 dataset to $RasterDataset
set $layer1 input 1 to band 1
$lasttran= last transform
set $lasttran limits to actual
add green layer
$layer2 = current layer
set $layer2 description "Green"
set $layer2 dataset to $RasterDataset
set $layer2 input 1 to band 2
$lasttran= last transform
set $lasttran limits to actual
add blue layer
$layer3 = current layer
set $layer3 description "Green"
set $layer3 dataset to $RasterDataset
set $layer3 input 1 to band 3
$lasttran= last transform
set $lasttran limits to actual
add height layer
$layer4 = current layer
set $layer4 description "Height"
set $layer4 dataset to $HeightDataset
set $alg view mode to perspective
new window
copy algorithm to window
go window
goto FinishUp
######################################################
#########
WizardCancel:
FinishUp:
exit
Batch scripting and wizards
245
246
Batch scripting and wizards
Scripting language
Batch scripts usually perform the following overall functions:
•
Input data or arguments from a user
•
Perform actions on specified objects
•
Output the results of the actions to screen and/or to disk
Input to batch
process.
Batch Engine
Input to batch
process
Output to screen
and/or disk
Script
ER Mapper
objects
Once a batch script has been invoked by a command from the user,
it generally requires the input of data or arguments before it can
perform any processing. In some unusual situations this input
information is “hard coded” into the script so that, apart from editing
the script, the user has no control over the batch process. This is
generally sufficient for “one-off” scripts which are developed to
perform a very specific set of tasks. It is often preferable to have
inbuilt default arguments which are used by the batch process in the
absence of any from the user. This makes the batch script more
flexible and, thus, more efficient.
You can also pass arguments to scripts from menu (.erm), and
toolbar (.bar) files and dynamic link choosers. See the “Menu
and toolbar files (.erm) and (.bar)”, and “Dynamic links
menu” chapters.
Scripting language
•
Methods for the user to input data are as follows:
•
Include arguments in the command line string.
•
Provide on-screen dialog boxes with controls and fields
•
Provide wizards which interactively prompt users to input data.
247
Command line arguments
This method is used when the user is running the batch file from a
command line using the ermapper -b command. The command
string syntax is as follows:
ermapper -b “batch_script [argument1 argument2]”
For example:
ermapper -b “copy_file image1.ers image2.ers”
All arguments after 'ermapper -b' need to be enclosed in double
quotes (“ ”).
The hypothetical batch script, copy_file.erb copies a image file
image1.ers, specified by argument1, to file image2.ers, specified
by argument2.
To run your script from a command line you must have the following
line at the end of the script:
exit
n
Where n is the exit code returned from ER Mapper.
Dialog boxes
•
n = 0: exits the script and leaves ER Mapper open.
•
n = >0: exits the script and closes ER Mapper.
There are a number of commands which create dialog boxes for
users to enter data.
The following script brings up a dialog box for input into ER Mapper.
The default title is “batch engine input”. The ask begin/end block
allows multiple inputs to be obtained from the user. The say
statements create a single line of text in the dialog box. The ask
statements create an alphanumeric entry box. The example below
opens a dialog box with the title ‘User Input Test’ and asks for an
algorithm file name, some text, a number and a yes-or-no answer.
ask begin
title “User Input Test”
say “Please enter a file name”
ask file “Algorithm:” “.alg” $file_name_input
say “Please enter some text”
ask text “Text:” $some_text_input
say “Please enter a number”
ask number “Number:” $some_number_input
say “Please select Yes/No”
ask yesno “YesNo:” $yesno_input
ask end
248
•
The input dialog is opened when the “ask end” statement is read.
•
There are a number of different types of field.
Scripting language
•
The input variables can be arrays.
•
To get multiple lines of text use multiple ask statements.
The above example will create the dialog box shown below:
Dialog box input fields
Scripting language
You can create the following types of input fields in dialog boxes
Refer to “Script commands - alphabetical listing” below for
descriptions of the command.
Type
Description
Script command
Band chooser
Entry box with a button to
open a chooser dialog listing
the band descriptions for the
specified file. You can also
specify multiple or single
choice.
ask bandchooser
Band menu
Drop down selection list of
descriptions for all the bands
in a specified file.
ask bandmenu
Color chooser
Alphanumeric entry box with
a button to open a color
chooser dialog
ask colorchooser
Datum chooser
Alphanumeric entry box with
a chooser button to open the
datum chooser dialog
ask datum
Directory chooser
Alphanumeric entry box with ask directory
a chooser button for entering
a directory name.
Exclusive generic list
List of defined entries with
exclusive radio buttons.
ask listmenu_exclusive
File
Alphanumeric entry box with
a file chooser button for
entering a file name.
ask file
249
Wizards
Type
Description
Script command
Generic list
Selection list containing
defined entries
ask listmenu
Grid layer
Drop down selection list of
descriptions for all the
gridding layers in a specified
project file.
ask gridlayermenu
Hardcopy driver
Alphanumeric entry box with ask hardcopy
chooser button to open either
the Windows printer driver or
the ER Mapper hardcopy
driver selection dialog box.
Link
Alphanumeric entry box with ask link
a link chooser button for
entering a dynamic link name
Lookup table
Drop down selection list of
the Color Lookup tables for
selection.
ask lutmenu
Navigation buttons
Button to select a defined
action
ask action
Projection chooser
Alphanumeric entry box with
a chooser button to open the
projection chooser dialog.
ask projection
Text and number
Alphanumeric entry box
ask text|number
Yes/No
Check box for selecting an
option.
ask yes/no
Wizards consist of a sequence of dialogs or pages through which a
user is led. Each wizard page contains a number of containers. These
wizard page containers have the same input fields as normal dialog
boxes. In the scripting language, wizard pages and containers are
defined by WizardPage begin..... WizardPage end, and
container begin.... container end statements.
WizardPage begin “Wizard Title
.......
container begin
.......
container end
container begin
.......
container end
.......
WizardPage end
An example wizard dialog page is shown below:
250
Scripting language
Containers
The following commands are used to create wizards. Refer to
“Script Commands - alphabetical listing” below for descriptions
of the commands
Function
Description
Script command
Wizard Page block
Starts a new wizard page
WizardPage begin|end
Close wizard
Closes the wizard
Wizard close
Container block
Creates a container within a
wizard page.
container begin|end
Container button
justification
Justifies button position
Container right|left
justify
Container position
Specifies how this container
is to be placed in relation to
another container
Container
above|below|left|right
Container item
positions
Specifies the direction of
placement of the items in a
container
Container Items
Container label
positions
Specifies where the labels for Container Labels
an item in the container will
appear
Container size
Specifies the container width Container width|height
and height as a percentage of
the remaining space.
Display image
Displays image in container
Using preferences to
remember settings
Scripting language
show image
ER Mapper maintains a list of preferences that can be retrieved at
any time. Using this facility, you can design wizards to “remember”
values entered by users so that they do not have to re-enter them
when they run the wizard again.
251
For example: a wizard could ask the user to enter a background color
which defaults to “white”. This value could be stored in a variable
$background_color. The value in $background_color could then be
stored as a preference. When the wizard is run again, it could
retrieve the $background_color value from the preference and thus
avoid having the user enter it again to change it from the default
value of “white”.
To set a preference
In the above example you use the following command to set the
preference:
set preference “Wizard:Image:BackGroundColor”
$background_color
This command assigns the value in variable $background_color to a
preference named “Wizard:Image:BackGroundColor”.
You can use any preference name, but it should be meaningful and
non-ambiguous. ER Mapper wizards use the “Class:Name:Variable”
format made up as follows:
•
Class: (e.g. Wizard)
•
Name: (e.g. Image)
•
Variable (e.g. BackGroundColor)
To retrieve a preference
In the above example you use the following command to retrieve the
preference:
$background_color = get preference
"Wizard:Image:BackgroundColor" "white"
This command assigns the value in preference
“Wizard:Image:BackgroundColor” to variable $background_color. It
defaults to “white” if the preference has not been set.
For syntax information see the “Preferences” and “Script
Commands - alphabetical listing” sections below.
252
Scripting language
ER Mapper
Objects.
Batch Engine
Input to batch
process
Script
ER Mapper
objects
Output to screen
and/or disk
ER Mapper comprises a number of objects which, in turn, contain
attributes. Batch scripts instruct the batch engine to perform actions
on these objects and their attributes. These actions can include
creating new instances of an object or setting specific attributes
pertaining to those objects.
The diagram below illustrates the objects and their relationships to
one another:
algorithm
surface
layer
formula
filter
transform
window
An algorithm object will contain surface objects which, in turn,
contain layer objects. The layer objects contain formula, filter and
transform objects.
The Window object is used for displaying algorithms copied to it.
Scripting language
253
All the objects can exist on their own within the batch engine; e.g.
you can have a defined layer object that is not contained within a
surface or algorithm. It is also possible to have an empty window.
However, you can only copy an algorithm (with its contained objects)
to a window to display it.
You can assign an object to a variable (e.g. an algorithm can be
assigned to $alg), and then use this variable to define that object in
your script. You can also set the batch engine to point to a specific
object; i.e. make it current. Any batch commands that do not name
a specific object will be performed on the current object.
For example,
select $alg[1]#makes $alg[1]the current algorithm
set algorithm mode to rgb
has the same effect as
set $alg[1] mode to rgb
Image Manipulation
When you write scripts to manipulate ER Mapper images and
algorithms, the algorithms you construct and edit with the scripting
language are within the batch engine—quite separate to ER Mapper
itself.
Thus, if you create an algorithm using a script, to view it you need
to copy it to ER Mapper.
Similarly, say you have an algorithm already being viewed and
edited in ER Mapper. A script to change the Color mode from
Pseudocolor to HSI must copy the algorithm from ER Mapper into the
batch engine, make the appropriate color mode change, and then
copy the resulting algorithm back to ER Mapper.
In the batch engine there are a number of reserved words which
point to objects.
254
•
current window: indicates the current window. When a batch
script starts, the current window is set to point to the currently
active window in the GUI.
•
current algorithm: indicates the current algorithm within the
batch engine
•
current surface: indicates the current surface within the
algorithm
•
current layer: indicates the current layer within the surface
•
current formula: indicates the current formula within the layer
•
current transform: indicates the current transform within the
layer
•
current filter: indicates the current filter within the layer
•
current input: indicates the current layer input within the layer
Scripting language
window, algorithm, surface, layer, transform, filter, and input usually
refer to the current object. Some examples:
$win1 = current window
means set $win1 to the current window.
copy window
means copy the current window, and update the current window
pointer to refer to the new window.
$win = copy window
means copy the current window, update the current window to refer
to the new window, and set $win to refer to the new window.
select $win
means make the window defined by the variable $win the current
window.
To give you a feel for how ER Mapper and the batch engine interact
with each other here are some examples to work through. These are
all from the ERMAPPER\batch directory. Please look through the
other script files for more extensive examples.
This first example copies the algorithm to the batch engine, the
included file sets up the layers for the colordrape algorithm, then the
lut and algorithm description are set. The changed algorithm must
be copied back to the window before the user sees the result.
#from Create_CD.erb to create a colordrape algorithm
copy algorithm from window
#include code to create the colordrape layers
include "lib/Create_CD.erb"
set algorithm lut to "pseudocolor"
set algorithm description to "Colordrape"
copy algorithm to window
exit
Scripting language
255
This more extensive example is part of
lib\Clip_99_All_Active_Layers.erb. It is included in the
‘Go_Limits_99.erb’ script. The algorithm has already been copied to
the batch engine.
# Run the Algorithm at 100x100 resolution
#
go algorithm 100 100
# Cycle through all layers setting limits to actual data limits
#
first active raster layer
if ($ERROR != 0) then goto no_algorithm
next_active_layer:
last transform
set transform limits to actual
next active raster layer
if ($ERROR == 0) then goto next_active_layer
# Run the Algorithm at 100x100 resolution.
#
go algorithm 100 100
# Cycle through all layers setting the transform clip to 99.0%
#
first active raster layer
if ($ERROR != 0) then goto no_algorithm
next_active_layer:
last transform
set transform clip to 99.0
next active raster layer
if ($ERROR == 0) then goto next_active_layer
no_algorithm:
256
Scripting language
Actions
The batch engine controls the objects by performing actions on
them. The following table lists these actions and shows their
applicable objects. See “Script Commands - alphabetical
listing” below for a full description of each command. The specific
page numbers for the commands are shown in brackets
Object types
Command
windo
w
algorithm
add
copy
*
copy to
*
*
Comment
surface
laye
r
trans
-form
formula
filter
*
*
*
*
*
Add object to a
containing
object.
*
*
*
*
*
Duplicate object
but do not insert
into another
object.
Copy algorithm
to and from
window for
display
copy from
current
*
*
*
*
*
*
*
Point to current
object
delete
*
*
*
*
*
*
*
Delete object
*
*
*
*
*
Make a duplicate
of the object and
insert it into the
containing object
*
*
*
*
*
Point to object
and make it
current
duplicate
first, last, next,
previous
*
*
fit page
*
get
*
Fit algorithm
page to hardcopy
device.
*
*
*
*
*
Get the value of
the specified
attribute.
See
“Attributes”
below for a list of
the attributes
go
*
go background
*
Scripting language
*
Run the object
Run object in
background
257
Object types
Command
windo
w
load
algorithm
*
*
*
save
laye
r
trans
-form
*
move
new
surface
*
*
*
*
formula
filter
*
*
Comment
Load algorithm,
formula or filter
into the batch
engine.
Move to new
position.
*
*
*
*
Create new
object
*
*
Save object to
file.
select
*
*
*
*
*
*
*
Make specified
object current
set
*
*
*
*
*
*
*
Set the value of
the specified
attribute. See
“Attributes”
below for a list of
the relavant
attributes.
turn on
*
*
Turn object on or
off
turn off
Attributes
The objects have attributes associated with them. You can use the
set and get commands to either set the attributes to required values
or interrogate the object to return the values of specific attributes.
The following table lists the attributes and shows which objects they
are asociated with. It also indicates whether you can perform sets
and/or gets on them. See “Script Commands - alphabetical listing”
for a full description of each command.
Object types
Attribute
algorith
m
azimuth
background
cell sizex
surface
laye
r
set/get
set
trans
-form
formul
a
filter
Comment
Sun shade azimuth
Specifies the background
color as an rgb value or a
color defined by a color
variable.
get
Cell size
get
Cell type
cell sizey
cell type
258
Scripting language
Object types
Attribute
algorith
m
surface
laye
r
clip
trans
-form
formul
a
set
color
filter
Comment
Percentage clip
set/get
Link layer color specified
by rgb values or defined
in a colorval variable.
contents
set/get
Page contents extents
contents extents
set
Set page contents
extents to algorithm
extents.
coordsys
set/get
Sets the coordinate
system type.
dataset
set/get
datum
set/get
description
set/get
Layer image file name
Sets the datum
set/get
set/get
set/get Description text
edit program
set/get
Edit program name
(dlink)
editable
set/get
Editable flag true or false
elevation
set/get
Sun shade elevation on
or off
equalize
set
Set to histogram or
gaussian equalize
formula
get/set
/load/s
ave
load/save
init program
set/get
Init program name
input count
get
Number of inputs
input filter count
get
Number of filter inputs
input to band
set
input transform
count
get
input
Sets the formula as a
text value, or loads a
formula (.frm) file.
Formula input to band
Number of input
transforms
set/get
Input/output limits
output
layer count
get
get
Number of layers
limits
set
Transform limits
link extensiom
set/get
Link file extension
link type
set
Sets link type to monoor truecolor
Scripting language
259
Object types
Attribute
lut
algorith
m
surface
set/get
set/get
laye
r
trans
-form
formul
a
filter
Comment
Sets the color table for
the specified surface or
first surface in an
algorithm.
matrix
set/get Element in filter matrix
mode
set/get
mosaic type
set/get
name
set/get
Sets the color mode for
the specified surface or
first surface in an
algorithm.
Sets the mosiac type to
overlay or feather
set
Name text
output filter count
get
Number of output filters
output transform
count
get
Number of output
transforms
page
autovary_value
set
Calculate autovary value
page border
set/get
Page borders
page center
set
Center image on page;
yes/no
page constraints
set/get
Page constraints
page extents
set
Page extents
page scale
set/get
Page scale
page size
set/get
Standard page size, e.g
“US Letter”
page topleft
set/get
Page extents coordinates
set/get
Inside dimesions of
page.
set/get
View image only or with
page layout.
page bottomright
page width
page height
page view mode
params
set/get Parameters
postsampled
set/get Postsampled process flag
projection
set/get
Image projection
rotation
set/get
Image rotation
260
Scripting language
Object types
Attribute
algorith
m
surface
laye
r
trans
-form
rows
scale
Comment
set/get Filter scale
shading
set/get
set
Sets sunshading to on or
off.
Supersample type
threshold
topleft
filter
set/get Number of rows and
columns.
cols
supersample type
formul
a
set/get Filter threshold value
set/get
Sets the extents.
bottomright
transparency
set
type
units
Surface transparency
set/get set/get
set/get
set/get Object type
Measurement units
userfile
set/get Source file name
userfunc
set/get Function name
view mode
set/get
View mode (2D/3D)
zoffset
set
Surface Z offset
zscale
set
Surface Z scale
Command summaries
The following sections summarize the commands applicable to the
different objects.
Refer to “Script Commands - alphabetical listing” for more
information on the commands.
Scripting language
261
Windows
algorithm
surface
layer
formula
filter
transform
window
Description
Command
Copies the window reference from win1 to $win2 = $win1
win2
Copies the algorithm from the current or
specified window to the batch engine and
set the current algorithm pointer to point
to it.
copy algorithm from window|$win
Copies the specified algorithm or that
copy algorithm to window
indicated by the current algorithm pointer
to the current window in ER Mapper.
Makes a duplicate of the current or
specified window and its algorithm
copy window|$win
Sets pointer to the current window.
current window
Deletes the current or specified window
and its algorithm.
delete window|$win
Updates the current window pointer to
first|last|next|previous window
point to the oldest ,newest, next oldest or
next newest window open.
Runs the algorithm in the current or
specified window as a background task
go background window|$win
Runs the algorithm in the current or
specified window.
go window|$win
Opens a new image window, with a
default algorithm
new window [x y w h]
Open the designated dialog box on screen open window
262
Scripting language
Description
Command
Zoom in or out using specified opition
previouszoom
zoom in|out
zoom to
Updates the current window pointer to
point to the given window.
select $win
Sets the mouse pointer to the specified
mode: zoom, zoombox, roam(hand) or
pointer.
set pointer mode to
zoom|zoombox|roam|pointer
Various geolink functionality
set window geolink mode
Algorithms
algorithm
surface
layer
formula
filter
transform
window
Description
Scripting language
Command
Sets $alg2 to refer to $alg1
$alg2 = $alg1
Copies the current or specified algorithm.
copy algorithm
Sets the pointer to the current algorithm
current algorithm
Deletes all references to an algorithm.
delete algorithm
Changes the current algorithm pointer to
point to the first, last, next or previous
algorithm.
first|last|next|previous algorithm
Gets the current or specified algorithm’s
description.
get algorithm description
263
Description
Command
Gets the algorithm’s coordinate system
type.
get algorithm coordsys
Gets the algorithm’s datum or projection
type.
get algorithm datum|projection
Gets the number of layers in the current
or specified algorithm.
get algorithm layer count
Gets the algorithm’s pseudocolor LUT
name.
get algorithm lut
Gets the algorithm’s mode.
get algorithm mode
Gets the algorithm’s mosaic type.
get algorithm mosaic type
Gets the algorithm’s extents.
get algorithm topleft|bottomright
eastings| longitude|meters_x
Gets the algorithm’s units or rotation.
Rotation is in decimal degrees, units is a
units string.
get algorithm units|rotation
Runs the current or specified algorithm.
go algorithm [width height][match]
Loads the given algorithm.
load algorithm $name
Creates a new (empty) algorithm.
new algorithm
Saves the current or specified algorithm
with the given name.
save algorithm $name
Saves the current or specified algorithm
as a virtual dataset
save algorithm as virtual dataset
$name
Saves the current or specified algorithm
as a dataset
save algorithm as dataset
Changes the current algorithm pointer to
point to the specified algorithm.
select $alg
Changes the algorithm’s background color set algorithm background to $red
to the given RGB values or to a value
$green $blue
specified by a variable.
set [algorithm] background to
colorval $colorvariable
Sets the algorithm’s coordinate system
type to the given type.
set algorithm coordsys to
$csys|raw|en|ll
Sets the algorithm’s datum or projection
set algorithm datum|projection
to the given type. This will cause layers of
an incompatible type to be turned off
within the algorithm.
Changes the current or specified algorithm set algorithm description to $text
description to the given text.
Changes the pseudocolor LUT for the first
surface in the algorithm to the given lut
file.
264
set algorithm lut [to] $lutname
Scripting language
Description
Command
Changes the processing mode for the first set algorithm mode to
surface in the algorithm to the given
$mode|pseudo|rgb|hsi
mode.
Sets the mosaic type (where different
datasets overlay) to the given type
set algorithm mosaic type
Sets the current or specified algorithm
supersample type.
set algorithm supersample type
Sets the current or specified algorithm
topleft and bottomright extent fields in
easting/northing, latitude/longitude or
raw coordinate systems.
set algorithm topleft|bottomright
Sets the units or rotation to the given
value.
set algorithm rotation|units to $units
Surfaces
algorithm
surface
layer
formula
filter
transform
window
If an algorithm has more than one surface, they have to be
individually defined and configured by these commands. This is not
necessary if the algorithm has only one surface because the
algorithm commands default to the top surface.
Description
Scripting language
Command
Adds the specified surface to the current
algorithm.
add $srf
Copies a the current or specified surface,
but does not add the new surface to any
algorithm
copy surface
265
Description
Command
Sets the pointer to the current surface.
current surface
Deletes the current or specified surface
from the current algorithm.
delete surface
Duplicates the current or specified surface duplicate surface
within the current algorithm.
Selects a surface within the current
algorithm and makes it current.
first|last|previous|next surface
Gets the current or specified surface
description.
get surface description
Gets the number of layers in the current
or specified surface.
get surface layer count
Moves the current surface within the
current algorithm.
move surface up|down|top|bottom
Creates a new surface but does not add it
to any algorithm.
new surface
Selects the given surface and makes it the select $srf
current surface.
Changes the current or specified surface
description to the given text.
set surface description to $text
Sets the Color Table for the current
surface.
set surface lut
Sets the color mode for the current
surface.
set surface mode
Sets the current surface name to the
given name.
set surface name
Sets the Z Scale, Z Offset or transparency set surface
of the current surface to $value.
zscale|zoffset|transparency
Checks whether current surface is active, surface active
and returns TRUE (1) for active and FALSE
(0) for inactive.
Enables/Disables the current surface.
266
turn surface on|off
Scripting language
Layers
algorithm
surface
layer
formula
filter
transform
window
All layer commands are related to the current surface. For example,
an add layer command will add the layer to the current surface.If
there is no designated current surface then it will default to the top
surface within the current algorithm.
Description
Command
Assigns specified layer (e.g. $lay1) to
another variable (e.g. $lay2)
$lay2 = $lay1
Adds the current or specified layer to the
current surface, at the end of the layer
list.
add layer
Adds a new layer of the given type after
the current layer in the current surface.
add layer
Copies the current or specified layer but
does not insert it into a surface.
copy layer
Sets the pointer to the current layer.
current layer
Deletes the current or specified layer.
delete layer
When all layers in a surface are deleted,
the surface will also be deleted unless it is
the only surface on the algorithm.
Duplicates the current layer in the current duplicate layer
surface.
Scripting language
Sets the current layer pointer to point to
the specified layer in the current surface.
first|last|next|previous layer
Gets the current or specified layer color.
Valid only on link layers.
get [layer] color
267
Description
Command
Gets the layers sun shading
azimuth/elevation.
get layer azimuth|elevation
Gets the number of bands in the current
or specified layer.
get layer band count
Gets the nominated band description of
the current or specified layer.
get layer band description
Reads the current or specified layer cell
size.
get layer cell sizex|sizey
Gets the current or specified layer’s image get layer cell type
cell type.
Gets the EN or LL coordinates from the
given cellX and cellY values.
get layer x_coordinate|y_coordinate
from $cellX $cellY
Gets the current or specified layer’s image get layer dataset
name.
268
Gets the current or specified layer’s
description.
get layer description
Gets the current or specified layer’s
editable flag. Valid only on link layers.
get layer editable
Gets the current or specified layer’s
edit|init program name.
get layer edit|init program
Gets a copy of the current or specified
layer’s formula.
get layer formula
Gets the number of inputs in the current
or specified layer.
get layer input count
Gets the number of input filters in the
current or specified layer input.
get layer input filter count
Gets the number of input transforms in
the current or specified layer input.
get layer input transform count
Gets the link file extension string for the
current or specified layer.
get layer link extension
Gets the number of output filters in the
current or specified layer.
get layer output filter count
Gets the number of output transforms in
the current or specified layer.
get layer output transform count
Gets the current or specified layer’s
shading value.
get layer shading
Gets the current or specified layer’s type.
get layer type
Checks whether the current layer is
active, and returns TRUE (1) for active
and FALSE (0) for inactive.
layer active
Scripting language
Description
Loads the formula file into the current or
specified layer’s formula.
Command
load layer formula
Moves the current or specified layer within move layer up|down|top|bottom
the current surface to the given position
within its surface.
Creates a new layer of the given type.
new layer
Moves the pointer to the next layer of the
type specified.
next [active][raster|vector] layer (type)
Saves the current or specified layer’s
formula to the formula file.
save layer formula
Sets the current layer pointer to point to
the specified layer.
select $lay
Sets the sun shade azimuth/elevation to
the given value in degrees.
set layer azimuth|elevation
Sets the current or specified layer color to set layer color
the given RGB or color values. Valid only
on link layers.
Sets the image file name for the current
or specified layer to $dsname.
set layer dataset
Changes the layer description to the text
given.
set layer description
Sets the editable flag for current or
specified layer. Valid only for link layers.
set layer editable [to] true|false
Sets the current or specified layer’s
set layer edit|init program
edit/init program to the given name. Valid
only on link layers.
Sets the current or specified layer
formula.
set layer formula
Sets the designated layer input to the
specified band number
set layer input $n1 to band $n2
Sets the link file extension of the current
or specified layer to the given string.
set layer link extension
Sets the link type of the current or
specified layer to monocolour or
truecolour. Valid only on link layers.
set layer link type to
monocolour|truecolour
Turns sunshading on/off for the current or set layer shading on|off
specified layer.
Scripting language
Changes the current or specified layer
type to the given type.
set layer type
Turns the current or specified layer on or
off.
turn layer on|off
269
Transforms
algorithm
surface
layer
formula
transform
filter
window
Description
Command
Assign specified transform (e.g. $tra1) to
another variable (e.g. $tra2).
$tra2 = $tra1
Adds the specified transform after the
current transform in the current layer.
add $tra
Adds the specified transform after the
current transform in the given stream
input of the current layer.
add $tra to layer input
Adds a transform of the given type after
the current transform.
add transform
Adds a point to the current or specified
transform at x, y.
add transform point
Makes a duplicate of the current or
specified tranform but does not insert it
into the current algorithm.
copy transform
Sets the pointer to the current transform. current transform
270
Deletes the transform, and all references
to it.
delete transform
Copies the current transform in the
current layer, and inserts the copy after
the current transform.
duplicate transform
Sets the current transform to the first,
last, next or previous transform in the
current layer. Optionally select an input
transform, and/or a transform type.
first|last|next|previous transform
Scripting language
Description
Command
Gets the current or specified transform’s
limits.
get transform input|output min|max
Gets the current or specified transform
type.
get transform type
Matches the existing output transforms of match transform [to $layer]
all layers to the current or specified layer
in the same surface.
Creates a new transform which then
becomes the current transform.
new transform
Sets the current transform to the specified select $tra
transform.
Scripting language
Applies a clip of $pct percent to the
current or specified transform.
set transform clip
Sets the current or specified transform
input/output limits.
set transform input|output min|max
Sets the current or specified transform
limits to $percent or actual.
set transform limits to
actual|$percent
Sets the current or specified transform’s
output limits to the input limits.
set transform output limits to input
limits
Applies a gaussian equalize operation to
the current or specified transform.
set transform to gaussian equalize
Applies a histogram equalize operation to
the current or specified transform.
set transform to histogram equalize
Sets the current or specified transform
type.
set transform type
271
Formula
algorithm
surface
layer
formula
filter
transform
window
Description
Command
Adds the current or specified formula to
the current layer.
add formula
Makes a copy of the current or specified
formula, but does not add it to a layer.
copy formula
Sets the pointer to the current formula.
current formula
Deletes the current formula in the current delete formula
layer.
Duplicates the current formula and addsi
it to the current layer.
duplicate formula
Sets the current formula pointer to point
to the specified formula in the current
layer.
first|last|next|previous formula
Loads the current or specified formula file. load formula $foname
272
Creates a new formula.
new formula
Saves the current or specified formula to
the formula file.
save formula to $foname
Sets the current formula to the specified
formula.
select $for
Sets the current or specified formula
($formula is a string).
set formula to $formula
Sets the current formula input to the
image band given.
set input $n1 to band $n2
Scripting language
Filters
algorithm
surface
layer
formula
transform
filter
window
Description
Command
Assigns specified filter (e.g. $fil1) to new
variable (e.g. $fil2)
$fil2 = $fil1
Adds the current or specified filter to the
current layer after the current filter.
add filter
Makes a copy of the current or specified
copy filter
filter but does not insert the new filter into
a layer.
Sets the pointer to the current filter.
current filter
Deletes the filter and all references to it.
delete filter
Copies the current filter, and inserts the
copy after the current filter.
duplicate filter
Sets the current filter to the first, last,
first|last|next|previous filter
next or previous filter in the current layer.
Scripting language
Gets the current or specified filter
description.
get filter description
Gets an element from the current or
specified filter matrix.
get filter matrix
Gets the current or specified user filter’s
parameters.
get filter params
Gets the current or specified filter’s post
sampled process flag.
get filter postsampled
Gets the number of rows/columns in the
current or specified filter.
get filter rows|cols
273
Description
Command
Gets the scale or threshold for the current get filter scale|threshold
or specified filter. Valid only on convolution
and threshold filters.
Gets the current or specified filter’s type.
get filter type
Gets the current or specified user filter
source file name.
get filter userfile
Gets the current or specified user filter
function name. Valid only on usercode
filters.
get filter userfunc
Loads the current or specified filter from
the given file.
load filter
Creates a new filter, but does not add it to new filter
any layer.
Saves the current or specified filter to the
given file.
save filter
Sets the current filter to the specified
filter.
select $fil
Changes the current or specified filter
description to the given text.
set filter description to $text
Sets an element of the current or specified set filter matrix
filter matrix. Valid only on convolution and
threshold filters.
Set the current or specified user filter
parameter string. Valid only on usercode
filters.
set filter params to $paramstring
Sets whether the current or specified filter set filter postsampled
can process resampled data, or source
data.
Sets the number or rows/columns for the
current or specified filter to $number.
set filter rows|cols
Sets the scale or threshold for the current set filter scale|threshold
or specified filter. Valid only on convolution
and threshold filters.
274
Sets the filter type of the current or
specified filter.
set filter type
Sets the current or specified user filter
source file, for a C usercode filter. Valid
only on usercode filters.
set filter userfile [to] $filename
Sets the current or specified user filter
function name. Valid only on usercode
filters.
set filter userfunc to $funcname
Scripting language
Page Setup
Description
Command
Sets the page width and height of the
current or specified algorithm to that of
the currently specified hardcopy device.
fit page to hardcopy
Gets the page contents extents
coordinates.
get contents topleft|bottomright
Gets the page borders of the current or
specified algorithm.
get page top|bottom|left|right
border
Get the page constraints of the current or
specified algorithm.
get page constraints
Gets the page scale of the current or
specified algorithm.
get page scale
Gets the page size of the current or
specified algorithm.
get page size
Gets the page extents coordinates.
get page topleft|bottomright
Gets the specified page parameter of the
the current or specified algorithm.
get page width|height
Calculates and sets the bottom right
set contents bottomright from topleft
contents extents coordinate, based on the
topleft coordinate, page size, borders, and
scale.
Sets the page contents extents
coordinates to that specified by $value.
set contents topleft|bottomright
Calculates one of the page setup variables set page autovary_value
based on the Constraints setting.
Centers the contents of the page
horizontally or vertically.
set page center horizontal|vertical
Sets the page constraints of the current or set page constraints to
specified algorithm.
$constr|zoom|page|border|scale
Scripting language
275
Description
Command
Calculates and sets the page extents of
the algorithm based on the contents
extents, the borders, and the scale.
set page extents from contents
Sets the page scale to a specific number
or the maximum scale possible.
set page scale to $scale|max
Sets the page size of the current or
specified algorithm.
set page size to $size
Sets the page extents coordinates to that
specified in the variable $value.
set page topleft|bottomright
Sets the page borders.
set page top|bottom|left|right
border
Sets the specified page size parameter of
the current or specified algorithm.
set page width|height
Set the contents extents to the algorithm
extents (where algorithm is the current
algorithm).
set contents extents to [algorithm]
extents
Page view mode
Description
Command
Gets the page view mode of the current or get page view mode
specified algorithm.
Sets the page view mode of the current or set page view mode to
specified algorithm to normal or layout.
$pvmode|normal|layout
View mode
276
Scripting language
Description
Command
Gets the view mode of the current or
specified algorithm.
get view mode
Sets the view mode of the current or
specified algorithm to 2D, 3D perspective
or 3D flythru.
set view mode to
$vmode|2d|perspective|flythru
Preferences
Preferences enable batch scrips to retain parameters when they are
shut down and re-run. There are a number of preferences already
defined in ER Mapper, but you can define and set new ones.
The following commands write to the user’s preference file.
Refer to “Script Commands - alphabetical listing” for
descriptions of these commands.
Function
Script command
Set preference entry
Adds or updates the named
preference entry
set preference
Get preference entry
Returns the value in the
named preference entry. Can
return a default value if the
entry does not exist.
get preference
Set color preference
entry
Adds or updates the named
color preference entry
set preference
Get color preference
entry
Returns the value in the
named color preference
entry. Can return a default
value if the entry does not
exist.
get preference
File and Path separators
Scripting language
Description
.
Function
Description
Script command
Build an absolute file
specification
Builds the absolute file
specification from a given
relative file specification and
its parent directory
build absolute filespec
<parent_dir> <rel_file>
Build a file path name
Builds a complete path for a
file from up to 4 given
elements.
build file path <element_
1> <element_2>
....<element 4>
Build a relative file
specification
Builds file specification
build relative filespec
relative to its parent directory <parent_dir> <abs_file>
from a given absolute file
specification.
277
Function
Other commands
Description
Script command
Convert file separators
Converts the file separators
in a given file specification
from English to native and
vice versa.
convert <filespec> to
english|native
sep|separator
Get English file
separator
Returns the standard English get english file
file separator used by the
sep|separator
host workstation or PC. This
would be “\” on a Win32 (PC)
platform or “/” on a Unix
platform.
Get native path|file
separator
Returns the path separator
used natively by the host
workstation or PC.
get native path|file
sep|separator
There are a number of commands that control the batch processing
environment. These are listed below:
Refer to “Script Commands - alphabetical listing” for
descriptions of these commands.
Function
Description
Script command
get file size
Gets the given file’s size in
bytes.
get $filename size
get free space on disk
Gets the amount of free
space, in bytes, on the given
disk.
get $diskname free space
get environment
variable
Gets the given environment
variable.
getenv $envname
set environment
variable
Sets the given environment
variable.
setenv $envname
delete directory or file Deletes a directory or file. If
the file name has an “.ers”
extension, the raster file is
also deleted.
delete $dir|$file
list contents of
directory
Lists the contents of the
specified directory into an
array.
listdir
edit text file
Edits the given file name in a edit $filename
text editor. The file is created
if it doesn’t exist.
exit batch process
Exits the batch process and
exit
returns you to the ER Mapper
main window. See also
“Command line
arguments”.
278
Scripting language
Function
Description
Script command
file exists
Verifies the existence of the
if $filename exists
specified file and returns true
or false.
split string into array
Splits the given string into an split $string at $token
array of substrings at the
given token
format number of
digits after decimal
point
Formats a number to have a
specified number of digits
after the decimal point .
format $input_value
$precision
get ER Mapper version Returns the ER Mapper
get version_string|
number
version number as a string or version_number
as a number.
execute system
command
Executes a system command
system $command
system command
status dialog
Similar to the system syntax, system $command status
except that a progress dialog ["title"]
is created.
File name, extension
and path keywords
Returns the file name, path
and extension of a given file
specification
filename $string
dirname $string
fileext $string
Color keywords
You can use the color_red,
color_green and
color_blue keywords to get
the rgb (0-255) components
of a color variable.
$bg_color color_red
$bg_color color_green
$bg_color color_blue
Output.
Batch Engine
Input to batch
process
Output to screen
and/or disk
Script
ER Mapper
objects
The results of a batch process can be directed to an image window,
to a Batch Engine Dialog box, or to be saved as a file.
Scripting language
279
Output to image window
To view an algorithm on the screen, you have to copy it to a window
object. The following commands load an algorithm into the current
algorithm object, and then copy it to the current window.
load algorithm "test_algorithm.alg"
copy algorithm to window
Output to file
You can copy instances of the following object types to a file using
the ‘save’ command:
•
algorithm
•
formula
•
filter
Examples of the save commands are given below:
save
save
save
save
save
save
Output to Batch Engine
Output dialog (print
commands)
algorithm "my_alg.alg"
algorithm as dataset "my_image.ers"
algorithm as virtual dataset "my_image_vds.ers"
layer formula "my_form.frm"
formula "my_form.frm"
filter "my_filter.ker"
The Batch Engine Output dialog opens automatically when you use
‘print’ commands. New print commands append text to that what
exists in already open dialogs.
There are two print commands:
print no CR/LF
println CR/LF
By default, numbers are printed to 6 decimal places. Use the ~ to
specify a different number of decimals.
statement
280
result
print 1
1.000000
$var = 2
print $var
2.000000
Scripting language
statement
result
$text = "Hello World"
print $text
Hello World
$text = "Hello World"
print $text
println $text
Hello WorldHello World
print ~3 1
1.000
The print and println commands write to an output dialog by default.
Alternatively, you can print out to a file using:
set output to $filename
The print or println commands in a batch script after this set
command will create the file if it doesn’t already exist and write the
output to the end of the file.
To reset the output to write to a dialog use the following command:
set output to output window.
Warning dialog
You can use the ‘say warning’ command to open an ER Mapper
warning dialog box with a specified message. The following is an
example of its use:>
checkdataset:
if ($filename!= "") then goto DatasetOK
say warning "Please enter a filename"
goto wizard_page_1
DatasetOK:
Status dialog
You can create a status dialog box which indicates the progress, as
a percentage and/or as text, of any process the user has invoked.
This is usually used in wizards
...
ask action "Status" goto OpenStatus
...
OpenStatus:
open status
$percent = 20
say status $percent ”Opening image window\n”
....
goto wizard_page_1
Scripting language
281
The following commands create and write to a status or warning
dialog box.
There is only one status dialog. If it is already open, new
messages will be added to it.
Refer to “Script Commands - alphabetical listing” for
descriptions of the commands.
Script command
Description
open status
Opens status dialog
say status
Adds message to status dialog
delete status
Deletes status dialog
say warning
Opens warning dialog with a message.
Library of batch
scripts
Common batch script functions are stored in
%ERMAPPER%\batch\lib. These can be included in your scripts. For
example, if you include lib\BE_Startup.erb, you get $machine_type,
$ERMAPPER, $ERMBIN and $ERMSCRIPTS and a number of other
variables defined for you.
Browse through the directory to see what is available. Some of the
scripts include others, so study them to see how to include the code
in your script.
282
Scripting language
Scripting reference
This chapter lists and describes all the operators, functions,
variables, keywords and commands used in the ER Mapper batch
scripting language.
All variable names, label, and keywords are case insensitive.
Operators
The full suite of standard operators is available.
•
#: Specifies a comment line. For example,
# this is a comment
•
= * / + - %: Standard arithmetic operators: assignment,
multiplication, division, addition, subtraction, modulus
•
!= <> > >= < <= ==: Standard comparison operators: not
equal to, not equal to, greater than, greater than or equal to, less
than, less than or equal to, equal to
•
~: Specifies the number of decimal places to print for numbers.
For example,
print ~3 $var
prints $var to 3 decimal places.
Concatenation
•
(): For assigning operator precedence.
•
[]: Array specifier.
The Batch engine can add numbers to strings. Numbers are
converted into text and joined to the end of strings.
Example
$number = 6
$string = "datasetname"
$string = $string + $number + ".ers"
Mathematical
functions
Scripting reference
•
sin(x), cos(x), tan(x): The sine, cosine and tangent of the angle
x, with the angle specified in radians.
•
asin(x), acos(x), atan(x): The arcsine, arccosine and arctangent
of the angle x, with the angle specified in radians.
•
pow(x,y): The number x raised to the power of y.
•
log(x), exp(x): The natural log and exponent of x.
283
Variables
•
sqrt(x): The square root of x.
•
floor(x): The number x rounded down.
•
ceil(x): The number x rounded up.
•
min(x,y), max(x,y): The minimum and maximum of two
numbers x and y.
•
abs(x): The absolute value of x.
Variables have a $ leading character, followed by a letter and then
alphanumeric characters (including underscores).
Syntax:$variablename
Memory is allocated dynamically as assignments are made.
$var = 1
$var2 = $var
ER Mapper supports global name spaces for variables; i.e values set
in included scripts affect parent scripts.
Memory is freed as variables are deleted or when the script exits.
There are a number of types. Once a variable has been defined, its
type becomes fixed. For example, in the first statement below, the
assignment $a = 0 defines the variable $a as a number variable. The
second statement $a = "Hello" tries to assign a string to the number
variable and produces an error.
$a = 0
$a = "Hello"
The following types of variable are available.
•
Number: A floating point number. Numerical variables can use
the full suite of arithmetic operators: - * / + - %.
For example,
$var = 1 + 1
is equivalent to
$var = 2
$var2 = $var * 100
is equivalent to
$var2 = 200
•
String: Strings are enclosed in quotes. Allowable arithmetic
operators are: + +=
$hello = "Hello "
$world = "World"
$hello_world = $hello + $world
gives the result
284
Scripting reference
"Hello World"
•
•
•
•
•
Scripting reference
YesNo: Allowable values are:
•
yes or 1
•
no or 0
Mode: Allowable values are:
•
pseudocolor (or pseudo)
•
rgb
•
hsi
LayerType: Allowable values are:
•
pseudocolor
•
red
•
green
•
blue
•
hue
•
saturation (or sat)
•
intensity (or int)
•
classification (or class)
•
classdisplay
•
link
•
height
CoordSys: Allowable values are:
•
raw
•
en
•
ll
MosaicType: Allowable values are:
•
overlay
•
feather
285
•
•
•
•
•
•
•
286
PageViewMode: Allowable values are:
•
normal
•
layout
TransformType: Allowable values are:
•
linear
•
exp
•
log
•
hist
ViewMode: Allowable values are:
•
2d
•
perspective
•
flythu
FilterType: Allowable values are:
•
convolution
•
threshold
•
user
SuperSampleType: Allowable values are:
•
nearest
•
bilinear
References: You can also have string references to a:
•
Window
•
Algorithm
•
Layer
•
Formula
•
Transform
•
Filter
Color: A three part number variable which can be specified in two
ways:
Scripting reference
•
As a set of three numbers which represent the red, green and
blue components of the color. The syntax is:
$Color = [colorval] r,g,b
For example,
$Color = 124,5,5
$Color = colorval 124,5,5
•
As a string containing one of the named colors listed in the
ER Mapper color chooser. The syntax is:
$Color = colorval "known_color"
For example,
$Color = colorval "red"
•
•
Arrays
CellType: Allowable values are:
•
uint8
•
uint16
•
uint32
•
int8
•
int16
•
int32
•
ieee4
•
ieee8
MachineType: Can be used for creating system command paths,
etc. Allowable values are:
•
sun4
•
sun5
•
irix5
•
decalpha
•
hp
•
win32
You can have arrays of any type.
$array[1]
The array index can be a variable: $array[$var]. For example,
Scripting reference
287
$count = 3
$filename[$count] = "vegetation"
Multi-dimensional arrays are supported. For example,
$array[cars][red] = 1
You can specify the array index to start at any number, including
a negative value. We do, however, recommend that you restrict
this to 0 or 1.
Page size options
The page size options listed in the page setup dialog are special
strings that are recognised by ER Mapper. They can be included in a
listmenu chooser. For example,
$p_size_array[0] = "Custom"
$p_size_array[1] = "US Letter"
$p_size_array[2] = "US Legal"
$p_size_array[3] = "A1"
$p_size_array[4] = "A2"
$p_size_array[5] = "A3"
ask listmenu "Choose a page size from the list" "Page
size chooser" $p_size_array $p_size_choice
Keywords
288
ER Mapper supports the following keywords
above
absolute
action
active
actual
add
algorithm
all
annotation
as
ask
at
autovary_value
azimuth
background
band
bandchooser
bandmenu
batch
batch
begin
below
blue
border
bottom
build
cell
center
centre
class
classdisplay
classification
clip
close
color
color_blue
color_green
color_red
colorchooser
colorval
colour
colour_blue
colour_green
colour_red
colourchooser
colourval
cols
columns
constraints
container
contents
coord
coordinate
copy
count
current
dataset
datasets
datum
defaults
delete
description
dirname
down
Scripting reference
duplicate
edit
editable
elevation
else
end
equalise
equalize
exists
exit
extension
extention
extents
false
file
fileext
filename
filter
first
fit
format
formula
free
from
gaussian
geolink
geoposition
get
getenv
go
goto
green
hardcopy
height
horizontal
hsi
hue
if
image
in
include
info
init
int
intensity
items
job
justify
last
layer
left
limits
link
listmenu
listmenu_ exclusive
load
lut
lutmenu
main
match
matrix
mode
monocolor
monocolour
mosaic
move
name
new
newline
next
none
number
off
on
open
out
overview
page
parameters
params
path
point
pointer
postsampled
preference
preferences
previous
print
println
process
profile
program
projection
pseudo
pseudocolor
raster
realtime3d
red
relative
rgb
right
roam
roam
rows
sarturation
sat
save
say
scale
scattergram
screen
select
sep
separator
set
setenv
setup
shading
show
size
sizex
sizey
sleep
space
split
status
sunangle
supersample
surface
system
tempname
text
then
threshold_value
timestamp
title
Scripting reference
289
to
top
transform
transparency
traverse
true
truecolor
truecolour
turn
type
up
userfile
userfunc
vector
version_number
version_string
vertical
view
virtual
warning
width
width_pct
width_pixels
window
wizard
wizardpage
yesno
zoffset
Flow control
This section documents the flow control commands, with examples.
Labels
For labelling the program for ‘goto’s. (A ‘goto’ always refers to a label
within the same file; i.e local name space. This means that
ER Mapper can distinguish between a label in the main code and the
same on in an included file. Labels can be used for conditional or
unconditional control.
•
Syntax: labelname:
For example,
get_filenames:
Controls
•
goto: Unconditional control. For example,
label1:
goto label1
•
if ... then ... else: Conditional control. For example,
label1:
$var = 1
if ($var == 1) then goto label1
if ($var == 2) then goto label1 else goto label2
Explicit exit
if ($var == 1) then goto carryon
exit
carryon:
If you are running the batch script from the command line using
ermapper -b, the script must exit with a return code > 0 (e.g.
exit 1) to ensure that the ER Mapper application also exits. If
the script exits with exit or exit 0, then the command line
prompt will "hang" until you physically stop the ER Mapper
application.
290
Scripting reference
Looping
$count = 0
increment:
$count = $count + 1
if ($count <= 10) goto increment
Including files
Files must be specified by their absolute path or a path relative to
the ERMAPPER\batch directory. Please note that ER Mapper supports
forward (/) slashes for PC and Unix directory paths. It supports
backward slashes (\) on PCs only. To maintain portability between
platforms it is advisable to use forward (/) slashes.
•
Syntax: include "filename"
Example:
include "lib/BE_Startup.erb"
Error reporting
Some commands return an error code and text which are stored in
the following variables:
$ERROR: stores the error code
•
•
0 - successful
•
1 - unsuccesful
$ERROR_TEXT: stores the error text message
Commands that return an error code include: previous, next, first,
last, load, save
Script Commands
- Alphabetical
listing
This section lists all the script commands alphabetically, and
describes their operation and syntax.
absolute|relative path
Specifies whether the variable returned by ‘ask file’ or ‘ask link’ will be an absolute
filepath or relative to the current directory. The default is absolute.
Syntax: absolute|relative path
Example
relative path
ask file "File to contour:" ""$dsname ".ers,.alg" $dsname
Scripting reference
291
add (new) layer
Adds a new layer of the given type after the current layer in the current surface.
Syntax: add $stype|pseudocolor|red|green|blue|hue
|saturation|intensity|height|classification|classdisplay|link layer
$stype: Layer type variable: see “Variables” for allowed values.
Examples
add pseudocolor layer
This is the same as
new pseudocolor layer
add layer
add (new) transform (to layer)
Adds a transform of the given type after the current transform. If no type is specified,
it defaults to linear.
Syntax: add [$ttype|linear|exp|log|hist] transform
$ttype: Transform type variable: value can be linear, exp, log or hist
Examples
add transform
add linear transform
add filter (to layer)
Adds the current or specified filter to the current layer after the current filter.
Syntax: add [$ftype|convolution|threshold|user] filter|$fil
$ftype: Filter type variable: value can be convolution, threshold or user.
Examples
add $fil
add user filter
add formula (to layer)
Adds the current or specified formula to the current layer.
Syntax: add formula|$for
Example
add $form1
292
Scripting reference
add layer (to surface)
Adds the current or specified layer to the current surface, at the end of the layer list.
Syntax: add layer|$lay
Examples
add layer
add $new_layer
add surface (to algorithm)
Adds the specified surface to the current algorithm.
Syntax: add $srf
Example
add $add_surface
add transform (to layer)
Adds the specified transform after the current transform in the current layer.
Syntax: add $tra
Example
add $another_transform
add transform point
Adds a point to the current or specified transform at x, y.
Syntax: add transform|$tra point $x $y
$x $y: Numbers, representing point coordinates
Example
add transform point 20 40
add transform to layer input
Adds the specified transform after the current transform in the given stream input of
the current layer.
Syntax: add $tra to layer input $count
$count: Number representing layer input number
Example
$count = 2
add $tra1 to layer input $count
add $tra1 to layer input 2
Scripting reference
293
algorithm2 = algorithm1
Sets $alg2 to refer to $alg1.
Syntax: $alg2 = $alg
They refer to the same object, so deleting one of them will cause them both
to become invalid. Use the copy command to create separate objects.
ask action
Defines a button and the action to be carried out if it is selected by a user.
Syntax: Ask Action "Button_Name" [[Close] Goto Label]
"Button_Name": The text to appear on the button.
Close: (Optional). Closes the wizard before carrying out the ‘Goto Label’.
Goto Label: (Optional). Specifies the label to go to in the script if the user presses the
button. If omitted, the button is made inactive and shaded out.
Example
The following define the buttons used on the first page of a multi-page wizard
In the above example, the "Back" button will be greyed out because no
GoTo Label is specified.
Similarly, an action button can be put inside the user area of a form, for example:
Ask Action "Configure …" Goto Configure_form
There is a ‘Close’ parameter on the ‘Ask Action’ command, as well as an explicit
"Wizard Close" command. They are designed with different circumstances in mind. The
‘Close’ parameter on the ‘Ask Action’ command is primarily designed for quick error
pop-up windows, which generally report an error to the user, then pop down, and go
straight back to the page that needs more data entered.
294
Scripting reference
ask bandchooser
Creates a chooser dialog which lists the descriptions for all the bands in the specified
file.
Syntax: ask bandchooser "prompt text" "title" p_dsh_name
[single_band_flag consec_flag] $bandchoice
"prompt text" : The text which appears to the left of the drop down list.
"title": Title of the chooser dialog.
p_dsh_name: The dataset header file (.ers) name.
single_band_flag: (Optional) Specifies the number of bands that can be selected.
Can be either:
•
0 - multiple bands may be selected
•
1 - only one band may be selected
If it is not included it is set to 0 by default. If it is included the consec_flag
must also be included. If it is set to 1, the consec_flag should be set to 0.
consec_flag: (Optional) Automatically selects the both the real and imaginary bands
when one or the other is selected. This is designed specifically for specifying bands for
FFT. Can be either:
•
0 - has no effect
•
1 - select real and imaginary bands for FFT
If it is not included it is set to 0 by default. If it is included the
single_band_flag must also be included. If it is set to 1, the
single_band_flag should be set to 0.
single_band_flag and consec_flag are optional, but must be used together
(i.e. either none or both must be specified)
$band_choice: The variable into which the selected band or bands are stored as a
string.
Examples
ask bandchooser "Band Menu" "Band Menu Chooser" $filename1 0 1
$BANDSTRING
ask bandchooser "Band Menu" "Band Menu Chooser" $filename1
$BANDSTRING
This stores the choice as a string e.g. 1-3,5,7 and is intended for use with
FFT and classification wizards (i.e. wizards that run an executable which
takes a band list as an input parameter).
Scripting reference
295
ask bandmenu
Creates a drop down list of the descriptions for all the bands in the specified file. The
band list in the process diagram in the Algorithm dialog is an example of this.
Syntax: ask bandmenu "prompt text" p_dsh_name $bandchoice
"prompt text": The text which appears to the left of the drop down list.
p_dsh_name: The dataset header file (.ers) name.
$bandchoice: The band number of the chosen band.
Example
ask bandmenu "My menu" $filename $band_choice
ask colorchooser|ask colourchooser
Adds a color chooser button that will open the standard color chooser.
Syntax: ask colorchooser "prompt text" "title" $color
ask colourchooser "prompt text" "title" $color
"prompt text": The text which appears to the left of the drop down list.
"title": The title of the chooser.
$color: The ColorType variable in which the name of the chosen color is stored.
Example
ask colorchooser "Choose a color" "My color title" $colorchoice
ask datum
Adds a file chooser button that will open the standard datum chooser.
Syntax: ask datum "label" $datum_name
"label": The title of the chooser.
$datum_name: A variable in which the chosen datum from the list is stored.
ask directory
Adds a button that will open a directory chooser.
Syntax: ask directory "label" $dir_name
"label": The title of the chooser.
$dir_name: A variable in which the chosen directory is stored. You can preset this as
a default directory.
Example
$dir_name = “C:\Program Files\ERDAS\ERDAS ER Mapper
7.2\examples”
ask directory "Directory:" $dir_name
296
Scripting reference
ask file
Adds a file chooser button to the alphanumeric entry field.
Syntax: ask file "prompt text" "default_directory" "default_file" ".ext"
$file_name
"prompt text": The text appears to the left of the entry box. If you don’t want a
prompt string use empty quotes: ""
"default_directory": (Optional). The default directory to show in the file chooser,
relative to the default directory for the file type. Omit this field if you specify a default
file.
"default_file": (Optional). A default file to show in the file chooser. Use the absolute
path name or path relative to the default directory for the file type.
".ext": A comma separated list of file extensions of the files to be listed in the file
chooser. Specify ".ANYRASTER" if you want to list all image files supported by ER
Mapper.
$file_name: A text variable for storing the file name selected using the file chooser.
Example
ask file "Input algorithm or dataset:" ".ers,.alg" $alg_name
You can only use the “default_file” parameter to specify .ers files. To
specify another file type as a default, initialize the $file_name variable with
the default file name. For example:
$outfile = "c:\temp\output.cc8"
ask file "Output dataset: " "" ".cc8" $outfile
ask gridlayermenu
Creates a drop down selection list of the descriptions for all the layers in the specified
gridding project file.
Syntax: ask gridlayermenu "prompt text" $project_file $layerchoice
"prompt text": The text which appears to the left of the drop down list.
$project_file: String containing the path and name of the gridding project file.
$layerchoice: The layer number of the chosen layer.
Example
ask gridlayermenu "Grid Layer:" $grid_project_filename
$grid_layer
Scripting reference
297
ask hardcopy
Asks the user to specify a hardcopy device. The two different types of drivers that are
available on the pc platform are erm_driver (ermapper hardcopy control files) and
win32_driver (win32 printer drivers). The driver_type option is ignored for unix
platforms (erm_driver is used regardless of the driver type).
Syntax: ask hardcopy erm_driver|win32_driver "prompt text"
erm_driver: Add button to open the Default Hardcopy chooser
win32_driver: Add button to open the Windows Print Setup dialog.
"prompt text": The text which appears above the entry box.
Example
ask hardcopy win32_driver “Please specify a printer driver”
ask link
Adds a dynamic link chooser button to the alphanumeric entry field.
Syntax: ask link "prompt text" chooser_program $var
"prompt text": The text that appears to the left of the entry box. If you don’t want a
prompt string use empty quotes:""
chooser_program: The dynamic link chooser program to run. This field is equivalent
to the sixth parameter in the dynamic link menu file. See the “Menu entry
parameters” and “Link chooser parameter” sections.
$varL: A variable for storing the chosen data.
Example
ask link "" "$$CHOOSER=arc_chooser $DEFAULT" $ws_file
298
Scripting reference
ask listmenu
Adds a list containing entries of any defined type.
Syntax: ask listmenu "prompt text" "title" $array_name $choice
"prompt text": The text which appears to the left of the drop down list.
"title": The title of the chooser.
$array_name: The name of the array which holds the choices to be listed in the
chooser.
$choice: A variable in which the chosen item from the list is stored.
You can only select one option. You can have lists of the following types (or a mixture
of them):
Scripting reference
•
String
•
Value
•
LayerType
•
Algorithm Mode
•
ViewMode
•
Coordinate Space Type
•
Mosaic Type
•
CellType
•
TransformType
•
SuperSampling Type
•
Filter Type
•
Color
•
Page Constraint Type
299
The page constraint information is the same as that used in the Page setup dialog.
Most items are listed in the choosers exactly as they are defined in the $array_name
elements. However, in cases when the resulting lists would not be easy to understand
some other property is used instead. The cases this applies to and the property that is
listed in the chooser for each case are shown below.
Variable type: Property listed in chooser
Window/Destination: title
Algorithm: name
Stream: desc
Formula: name
Filter: name
Surface: name
You can’t have lists of transforms.
If the index for the pointer is null, the item will not show up in the list.
Example
$ARRAY_VARIABLE[1] = red
$ARRAY_VARIABLE[2] = green
$ARRAY_VARIABLE[3] = blue
...
# set the default
$ARRAY_VARIABLE_CHOICE = $ARRAY_VARIABLE[2]
ask listmenu "Choose a layer type from the list" "Layer Chooser"
$ARRAY_VARIABLE $ARRAY_VARIABLE_CHOICE
ask listmenu_exclusive
The same as ask listmenu, but all the chooser entries are listed in the dialog with
exclusive radio buttons (not a drop down list). Thus, this is best used with small
numbers of options only.
Syntax: ask listmenu_exclusive "prompt text" $Array_name $choice
"prompt text": The text which appears to the left of the drop down list.
$array_name: The name of the array which holds the choices to be listed in the
chooser.
$choice: A variable in which the chosen item from the list is stored.
300
Scripting reference
ask lutmenu
Adds a list of color lookup tables to choose from and stores the selection in a string
variable.
Syntax: ask lutmenu "prompt text" $lut_choice
"prompt text": The text which appears to the left of the list.
$lut_choice: The name of the chosen lookup table is stored in a string variable.
Example
ask lutmenu "Color Lookup Table" $lut_choice
ask projection
Adds a file chooser button that will open the standard projection chooser.
Syntax: ask projection "label" $proj_name
"label": The title of the chooser.
$proj_name: A variable in which the chosen projection from the list is stored.
ask text|number
Adds an alphanumeric entry box to the container.
Syntax: ask text "prompt text" $text_input
ask number "prompt text" $number_input
"prompt text": The text appears to the left of the entry box. If you don’t want a
prompt string use empty quotes: ""
$text_input: A text variable.
$number_input: A number variable.
Example:
ask text "Please enter your name:"$name
ask yes/no
Adds a check box to the container.
Syntax: absolute|relative path
"prompt text": The text appears to the left of the check box. If you don’t want a
prompt string use empty quotes:""
$yesno_input: A Yes/No variable.
Example:
ask yesno "Center Horizontally" $do_center_horiz
Scripting reference
301
build absolute filespec
Builds the absolute file specification from a given relative file specification and its
parent directory
Syntax: build absolute filespec <parent_dir> <rel_file>
parent_dir: The path and name of the parent directory
rel_file: The name and path of the file relative to parent_dir
Example
println build absolute filespec "c:/Program Files/ERDAS/ERDAS ER
Mapper 7.2/examples" "Data_Types\\Airphoto\\RGB.alg"
build file path
Builds a complete path for a file from up to 4 given elements by inserting the correct
file separators.
Syntax: build file path <element_ 1> [<element_2> [<element_3>
[<element 4>]]]
element_ : The path element.
Example
println build file path "c:\\Program Files\\ERDAS\\ERDAS ER
Mapper 7.2\\examples" "Data_Types" "Airphoto" "RGB.alg"
build relative filespec
Builds file specification relative to its parent directory from a given absolute file
specification.
Syntax: build relative filespec <parent_dir> <abs_file>
parent_dir: The path and name of the parent directory
abs_file: The name and absolute path of the file
Example
println build relative filespec "c:/Program Files/ERDAS/ERDAS ER
Mapper 7.2/examples" "c:\\Program Files\\ERDAS\\ERDAS ER Mapper
7.2\\examples\\Data_Types\\Airphoto\\RGB.alg"
Color keywords
You can use the color_red, color_green and color_blue keywords to get the rgb (0255) components of a color variable.
Example
$bg_color = 230,23,56
$red = get $bg_color color_red
$blue = get $bg_color colour_blue
302
Scripting reference
container right|left justify
This is used to justify a button or a row of buttons in a container. It will not affect other
item types such as lists and files as these are placed so as to make best use of the
existing space.
Syntax: [Container] right|left justify
Example
container right justify
ask action "< Back"
ask action "Next >"
container above|below|left|right
Optional command specifies how this container is to be placed in relation to another
container. The default is for the container to be below the previously defined container.
Syntax: [Container] Above|Below|Left|Right "Name"
“Name”: String with name of other container
Example
container below "con1"
container begin|end
A container block defines the size, contents and layout of a single ‘container’ or ‘pane’
in a wizard page. Any number of containers can be defined though realistically there
will be only two or three per page.
Syntax: container begin “Name”
.........
container end
"Name": Name is the name of the container within the script. Each of the containers
on a single page (within a single Wizard block) must have a different name.
Example
container begin "con2"
container height_pct 20
container below "con1"
ask action "< Back"
ask action "Next >" goto wizard_page2
ask action "Cancel" close goto wizard_page2
container end
Scripting reference
303
container items
Optional command specifies the direction of placement of the items in a container defined
between this command and the next Container Items command. If omitted, the items
will be placed vertically.
Syntax: [Container] [Items] Horizontal | Vertical | Newline
Examples
Container Items Horizontal
Horizontal
container labels
Optional command specifies where the labels for an item in the container will appear.
The default is ‘above’.
Syntax: [Container] Labels_above | Labels_left
Example:
Container labels_above
container width|height
Optional command specifies the container width and height as a percentage of the
remaining space.
Syntax: [Container] width_pct | height_pct $Percentage_number
$Percentage_number: Number, representing percentage value.
Examples
Container width_pct 30
width_pct 30
convert file separator
Converts the file separators in a given file specification from English to native
and vice versa.
Syntax: convert <filespec> to english|native sep|separator
filespec: File specification to be converted.
Example
$fspec = "c:/Program Files/ERDAS/ERDAS ER Mapper
7.2/examples/Data_Types/Airphoto/RGB.alg"
convert $fspec to native sep
304
Scripting reference
copy algorithm
Copies the current or specified algorithm. The current algorithm pointer is updated to
point to the new algorithm.
Syntax: copy algorithm|$alg
Examples
copy algorithm to window
copy $alg to window
$alg_copy = copy $alg # Note: not the same as $alg_copy = $alg
$alg_copy = copy algorithm
copy algorithm from window
Copies the algorithm from the current or specified window to the batch engine and set
the current algorithm pointer to point to it.
Syntax: copy algorithm from window|$win
Examples
copy algorithm from window
copy algorithm from $win
copy algorithm to window
Copies the specified algorithm or that indicated by the current algorithm pointer to the
current window in ER Mapper. Aborts if there is no current window
Syntax: copy algorithm|$alg to window
Examples
copy $original_algorithm to window
copy algorithm from window
copy filter
Makes a copy of the current or specified filter but does not insert the new filter into a
layer.
Syntax: copy filter|$fil
Example
$fil = copy filter
copy formula
Makes a copy of the current or specified formula, but does not add it to a layer.
Syntax: copy formula|$for
Example
$for2 = copy formula
Scripting reference
305
copy layer
Copies the current or specified layer but does not insert it into a surface.
Syntax: copy layer|$lay
Examples
$temp_layer = copy layer
copy surface
Copies the current or specified surface, but does not add the new surface to any
algorithm
Syntax: copy surface|$srf
Example
$new_surface = copy $srf1
copy transform
Makes a duplicate of the current or specified transform but does not insert it into the
current algorithm.
Syntax: copy transform|$tra
Examples
copy $tra1
$tra2 = copy $tra1
copy window
Makes a duplicate of the current or specified window and its algorithm, and then runs
the algorithm to display the duplicate. The current window pointer is updated to point
to the new window.
Syntax: copy window|$win
Examples
copy window
copy $win
current algorithm
Sets the pointer to the current algorithm. Can also be used to check whether an
algorithm currently exists
Syntax: current algorithm
Examples
$curr_alg = current algorithm
if current algorithm then goto have_algorithm
306
Scripting reference
current filter
Sets the pointer to the current filter.
Syntax: current filter
Example
$fil = current filter
current formula
Sets the pointer to the current formula.
Syntax: current formula
Example
$for1 = current formula
current layer
Sets the pointer to the current layer. This can also be used to check whether a current
layer exists.
Syntax: current layer
Examples
$layer2 = current layer
if current layer then goto layer_ok
current surface
Sets the pointer to the current surface.
Syntax: current surface
Example
$curr_surface = current surface
current transform
Sets the pointer to the current transform.
Syntax: current transform
Example
$tra1 = current transform
Scripting reference
307
current window
Sets pointer to the current window. This can also be used to check whether an image
window currently exists.
Syntax: current window
Examples
$win = current window
if current window then goto window_ok
delete algorithm
Deletes all references to an algorithm. If the algorithm deleted was the current
algorithm, the current algorithm pointer will be set to point to the next algorithm if one
exists, or the previous one, or aborts.
Syntax: delete algorithm|$alg
Examples
delete algorithm
delete $change_algorithm
delete directory|file
Delete a directory or file. If the file name has an “.ers” extension, the raster file is also
deleted.
Syntax: delete $dir|$file
$dir: String with path and directory name
$file: String with path and file name
Example
$temp_file = “examples/tempfile.ers”
delete $temp_file
delete filter
Deletes the filter and all references to it.
Syntax: delete filter|$fil
Example
delete filter
delete formula
Deletes the current formula in the current layer.
Syntax: delete formula
Example
delete formula
308
Scripting reference
delete layer
Deletes the current or specified layer. When all layers in a surface are deleted, the
surface will also be deleted unless it is the only surface on the algorithm.
Syntax: delete layer|$lay
Examples
delete $layer1
delete layer
delete status (dialog)
Deletes the status dialog. Note that there is only one status dialog for the batch
engine.
Syntax: delete status
Example
delete status
delete surface
Deletes the current or specified surface from the current algorithm.
Syntax: delete surface|$srf
Examples
delete $add_surface
delete surface
delete transform
Deletes the current or specified transform, and all references to it.
Syntax: delete transform|$tra
Example
delete $tra1
delete window
Deletes the current or specified window and its algorithm. If the one deleted was
current it updates the current window and current algorithm to the next window and
next algorithm. If there is no next window it sets them to the previous window and
previous algorithm.
Syntax: delete window|$win
Examples
delete window
delete $win
Scripting reference
309
duplicate filter
Copies the current filter, and inserts the copy after the current filter.
Syntax: duplicate filter
Examples
duplicate $fil
$fil1 = duplicate filter
duplicate formula
Duplicates the current formula, and inserts the copy after the current formula.
Syntax: duplicate formula
Examples
$form1 = duplicate formula
duplicate layer
duplicate layer
Duplicates the current layer in the current surface. The new layer is inserted after the
current layer.
Syntax: duplicate layer
Examples
$lay1 = duplicate layer
duplicate layer
duplicate surface
Duplicates the current or specified surface within the current algorithm.
Syntax: duplicate surface|$srf
Examples
$new_surface = duplicate surface
duplicate surface
duplicate transform
Copies the current transform in the current layer, and inserts the copy after the current
transform.
Syntax: duplicate transform
Example
duplicate transform
310
Scripting reference
edit file
Edit the given file name in a text editor. The file is created if it doesn’t exist.
Syntax: edit $filename
$filename: String with path and text file name, including extension.
Example
$toolbarname = “c:\Program Files\ERDAS\ERDAS ER Mapper
7.2\batch\toolbar.erb”
edit $toolbarname
exists
Verify that a specified file exists.
Syntax: $filename exists
$filename: String with path and name of file.
Example
if "c:\temp\temp.alg" exists then goto file_exists
exit
Exit the batch process and return to ER Mapper.
Syntax: exit [$exit_no]
$exit_no: Integer with return code. Only used if you are running the batch script from
the command line using ermapper -b. The script must exit with a return code > 0
(e.g. exit 1) to ensure that the ER Mapper application also exits. If the script exits
with exit or exit 0, then the command line prompt will "hang" until you physically
stop the ER Mapper application.
Example
if ($var == 1) then goto carryon
exit
carryon:
Scripting reference
311
File name, extension and path keywords
You can use the filename, dirname and fileext keywords to respectively return the
file name, path and extension of a given file specification. If there is no extension,
filename or path component it returns a null string ““
Examples
$string = “\examples\Shared_Data\airphoto.ers”
$fname = filename $string# returns “airphoto.ers”
$dirname = dirname $string# returns “examples\Shared_Data”
$ext = fileext $string# returns “.ers”
If $string = “c:\”, then dirname $string would return “c:\”; i.e it
retains the trailing slash for volumes.
If $string = “/examples/Shared_Data/airphoto.ers” then dirname
$string would return “examples/Shared_Data”.
filter2 = filter1
Assigns specified filter (e.g. $fil1) to new variable (e.g. $fil2)
Syntax: $fil2 = $fil1
$fil2 and $fil1 refer to the same object, so deleting $fil1 will invalidate $fil2.
Use the copy or duplicate command to create a new object.
Example
$fil2 = $fil1
first|last|next|previous algorithm
Changes the current algorithm pointer to point to the first, last, next or previous
algorithm.
Syntax: first|last|next|previous algorithm
Examples
next algorithm
$alg2 = last algorithm
312
Scripting reference
first|last|next|previous filter
Sets the current filter to the first, last, next or previous filter in the current layer.
Optionally selects an input filter, and/or a filter type.
Syntax: first|last [input $n] [$ftype] filter
next|previous [$ftype] filter
$n: Number, representing input number
$ftype: Filter type variable: value can be convolution, threshold or user.
Example
last input 2 filter
next threshold filter
first|last|next|previous formula
Sets the current formula to the first, last, next or previous formula in the current layer.
Syntax: first|last formula
next|previous formula
Example
last formula
next formula
first|last|next|previous layer
Sets the current layer pointer to point to the specified layer in the current surface. Sets
$ERROR to 1 if fails; otherwise 0.
Syntax: first|last|next|previous layer
Examples
$layer1 = first layer
first layer
Scripting reference
313
first|last|next|previous transform
Sets the current transform to the first, last, next or previous transform in the current
layer. Optionally select an input transform, and/or a transform type.
Syntax: first|last [input $n] [$ttype] transform
next|previous [$ttype] transform
$n: Number representing layer input number
$ttype: Transform type variable: value can be linear, exp, log or hist
Examples
last transform
$lasttran = last input 2 transform
next linear transform
$nextlin = next linear transform
first|last|next|previous window
Updates the current window pointer to point to the oldest, newest, next oldest or next
newest window open. Sets $ERROR to 1 if fails; otherwise 0.
Syntax: first|last|next|previous window
Examples
next window
$winlast = last window
first|last|next|previous surface
Selects a surface within the current algorithm and makes it current.
Syntax: first|last|previous|next surface
Examples
first surface
next surface
fit page to hardcopy
Sets the page width and height of the current or specified algorithm to that of the
currently specified hardcopy device.
Syntax: fit [$alg] page to hardcopy
Example
fit $alg page to hardcopy
314
Scripting reference
format value precision
Formats a number to have a specified number of digits after the decimal point.
Syntax: format $input_value $precision
$input_value: Number, representing original data to be formatted
$precision: Number, representing required number of digits after the decimal point.
Example
$arg1_formatted = format $template_tl_e_extent 3
get (page) contents topleft|bottomright
Gets the page contents extents coordinates.
Syntax: get [$alg] contents topleft|bottomright northings|latitude|meters_y
get [$alg] contents topleft|bottomright eastings|longitude| meters_x
Example
$template_tl_e_extent = get $alg contents topleft eastings
get algorithm coordsys
Gets the algorithm’s coordinate system type.
Syntax: get algorithm|$alg coordsys
Examples
$coordsys = get algorithm coordsys
$coordsys = get $alg coordsys
get algorithm datum|projection
Gets the algorithm’s datum or projection type.
Syntax: get algorithm|$alg datum|projection
Examples
$datum = get algorithm datum
$proj = get $alg projection
get algorithm description
Gets the current or specified algorithm’s description.
Syntax: get algorithm|$alg description
Examples
$desc = get algorithm description
$desc = get $alg description
Scripting reference
315
get algorithm layer count
Gets the number of layers in the current or specified algorithm.
Syntax: get algorithm|$alg layer count
Examples
$count = get algorithm layer count
$count = get $new_alg layer count
get algorithm lut (color table)
Gets the algorithm’s pseudocolor LUT name.
Syntax: get algorithm|$alg lut
Example
$alg_lut = get algorithm lut
get algorithm mode
Gets the algorithm’s mode. Returns “pseudo”, “rgb” or “hsi”.
Syntax: get algorithm|$alg mode
Examples
$algorithm_mode = get algorithm mode
if (get algorithm mode == pseudo) then goto newmode
get algorithm mosaic type
Gets the algorithm’s mosaic type. Returns overlay or feather.
Syntax: get algorithm|$alg mosaic type
Example
$mtype = get algorithm mosaic type
get algorithm topleft|bottomright (extents)
Gets the algorithm’s extents. Returns number.
Syntax: get algorithm|$alg topleft|bottomright eastings| longitude|meters_x
get algorithm|$alg topleft|bottomright northings| latitude|meters_y
Example
$extent1 = get algorithm bottomright longitude
316
Scripting reference
get algorithm units|rotation
Gets the algorithm’s units or rotation. Rotation is in decimal degrees, units is a units
string.
Syntax: get algorithm|$alg units|rotation
Examples
$alg_units = get algorithm units
$alg_rotate = get $alg rotation
get English file separator
Returns the standard English file separator used by the host workstation or PC. This
would be “\” on a Win32 (PC) platform or “/” on a Unix platform.
Syntax: get english file sep|separator
Example
println get english file sep
get file size
Gets the given files size in bytes. $filename is an absolute path name.
Syntax: get $filename size
$filename: String with path and file name
Example
$filename = “c:\Program Files\ERDAS\ERDAS ER Mapper
7.2\examples\myfile.alg”
$filesize = get $filename size
get filter description
Gets the current or specified filter’s description.
Syntax: get filter|$fil description
Examples
$desc = get filter description
$desc = get $fil1 description
get (usercode) filter params
Gets the current or specified user filter’s parameters.
Syntax: get filter|$fil params
Example
$param = get $filter1 params
Scripting reference
317
get filter postsampled (flag)
Gets the current or specified filter’s post sampled process flag. Returns boolean value.
Syntax: get filter|$fil postsampled
Example
$fpost = get filter postsampled
get filter rows|cols
Gets the number of rows/columns in the current or specified filter.
Syntax: get filter|$fil rows|cols
Examples
$frow = get filter rows
$fcol = get $fil1 cols
get filter scale|threshold (value)
Gets the scale or threshold for the current or specified filter. Valid only on convolution
and threshold filters.
Syntax: get filter|$fil scale|threshold
Example
$value = get filter threshold
get filter userfile (filename)
Gets the current or specified user filter source file name. Valid only on usercode filters.
Syntax:get filter|$fil userfile
Example
$fnme = get filter userfile
get (usercode) filter userfunc (filename)
Gets the current or specified user filter function (.dll) name. Valid only on usercode
filters.
Syntax: get filter|$fil userfunc
Example
$funcname = get filter userfunc
get filter type
Gets the current or specified filter’s type. Returns convolution, threshold or user.
Syntax: get filter|$fil type
Example
$ftype = get filter type
318
Scripting reference
get free space (on disk)
Gets the amount of free space, in bytes, on the given disk.
Syntax: get $diskname free space
$diskname: String with path and directory name
Example
$diskname = “c:\Program Files\ERDAS\ERDAS ER Mapper
7.2\examples”
$free_space = get $diskname free space
get layer azimuth|elevation
Gets the layer sunshading azimuth or elevation. Returns degrees as a number.
Syntax: get layer|$layazimuth|elevation
Example
$angle = get layer elevation.
get layer band count
Gets the number of bands in the current or specified layer.
Syntax: get layer|$lay band count
Example
$band_count = get layer band count
get layer band description
Gets the nominated band description of the current or specified layer.
Syntax: get layer|$lay band $n description
$n: Number, representing band number
Example
$band_desc = get layer band 1 description
get layer cell sizex|sizey
Reads the current or specified layer cell horizontal or vertical size.
Syntax: get layer|$lay cell sizex|sizey
Examples
$cell_sizex = get $layer1 cell sizex
$cell_sizey = get layer cell sizey
Scripting reference
319
get layer cell type
Gets the current or specified layer’s image cell type.
Syntax: get layer|$lay cell type
Example
$lay_celltype = get layer cell type
get layer color
Gets the current or specified layer color. Valid only on link layers.
Syntax: get [layer|$lay] color
Examples
$layer_color = get color
$layer_color = get $layer color
get layer coordinates
Returns the EN or LL layer coordinates from the given cellX and cellY values.
Syntax: get layer x_coordinate|y_coordinate from $cellX $cellY
$cellX $cellY: Integers with X and Y cell coordinate values
Examples
$tlx
$tly
$brx
$bry
=
=
=
=
get
get
get
get
layer
layer
layer
layer
x_coordinate
y_coordinate
x_coordinate
y_coordinate
from
from
from
from
$StartColumn $StartRow
$StartColumn $StartRow
$EndColumn $EndRow
$EndColumn $EndRow
get layer dataset (filename)
Gets the current or specified layer’s image name.
Syntax: get layer|$lay dataset
Examples
$dsname = get layer dataset
if (get layer dataset !=““) then goto make_cdrape
get layer description
Gets the current or specified layer’s description.
Syntax: get layer|$lay description
Example
$lay_desc = get $layer1 description
320
Scripting reference
get layer editable (flag)
Gets the current or specified layer’s editable flag. Valid only on link layers. Returns true
or false.
Syntax: get layer|$lay editable
Example
$edit = get layer editable
get layer edit|init program (name)
Gets the current or specified layer’s edit|init program name.
Syntax: get layer|$lay edit|init program
Example
$init_program = get layer init program
get layer formula
Gets a copy of the current or specified layer’s formula. Returns a structure useable by
formula commands but not println.
Syntax: get layer|$lay formula
Example
$form = get $layer1 formula
get layer input filter count
Gets the number of input filters in the current or specified layer input.
Syntax: get layer|$lay input $index filter count
$index: Number representing input number.
Example
$count = get layer input $index filter count
get layer link extension
Gets the link file extension string for the current or specified layer.
Syntax: get layer|$lay link extension
Examples
$l_ext = get $layer1 link extension
if (get layer link extension == “.erv”) then goto process_vector
Scripting reference
321
get layer output transform count
Gets the number of output transforms in the current or specified layer.
Syntax: get layer|$lay output transform count
Example
$count = get $layer1 output transform count
get layer shading
Gets the current or specified layer’s shading value. Returns on or off
Syntax: get layer shading
Example
$shaded = get layer shading
get layer type
Gets the current or specified layer’s type. Returns a layer type value. See
“Variables”.
Syntax: get layer|$lay type
Example
$ltype = get layer type
get layer|$lay input count
Gets the number of inputs in the current or specified layer.
Syntax: get layer|$lay input count
Example
$count = get layer input count
get layer visibility
Determines if any part of the current or specified layer is turned on and lies within the
extents of the algorithm.
Syntax: get layer|$lay visibility
Example
$layer_visible = get $layer1 visibility
$layer_visible = get layer visibility
322
Scripting reference
get native path|file separator
Get the path or file separator used natively by the host workstation or PC.
Syntax: get native path|file sep|separator
Example
println get native path separator
println get native file sep
get page constraints
Get the page constraints of the current or specified algorithm. Returns zoom, page,
border or scale.
Syntax: get [$alg] page constraints
Example
$page_constraint = get $alg page constraints
get page scale
Gets the page scale of the current or specified algorithm.
Syntax: get [$alg] page scale
Example
$page_scale = get $alg page scale
get page size
Gets the page size of the current or specified algorithm. Returns string with page size;
e.g. “US Letter”.
Syntax: get [$alg] page size
Example
$page_size = get $alg page size
get page topleft|bottomright (extents)
Gets the page extents coordinates.
Syntax: get [$alg] page topleft|bottomright northings|latitude|meters_y
get [$alg] page topleft|bottomright eastings|longitude| meters_x
Example
$tl_e_extent = get $alg page topleft eastings
Scripting reference
323
get page top|bottom|left|right border
Gets the page borders of the current or specified algorithm.
Syntax: get [$alg] page top|bottom|left|right border mm|inches
Example
$page_top = get $alg page top border inches
get (algorithm) page view mode
Gets the page view mode (normal or page layout) of the current or specified algorithm.
Syntax: get [$alg] page view mode
Example
$pvmode = get page view mode
get page width|height
Gets the specified page parameter of the current or specified algorithm,
Syntax: get [$alg] page width|height inches|mm
Example
$page_width = get $alg page width mm
get preference
Gets the value of the preference name from the preference file. Returns specified
default value if entry does not exist.
Syntax: get preference "name"
$default_string|$default_number[boolean|integer|d
ouble]
“name”: String with name of entry in preference file. Suggested standard format is
“Class:Name:Variable.
$default_string: String with default value for entry
$default_number: Number with default value for entry
Example
$ImageVersion = get preference “Wizard:Image:Version” 1.0
324
Scripting reference
get preference (color)
Gets the color preference entry in the user’s preference file. Set to specified default
value if the entry does not exist.
Syntax: get preference "colorname" $red $green $blue
get preference "colorname" colorval $default_color|$red,$green,$blue
“colorname”: Color preference entry name
$red $green $blue: RGB numeric values for the default color.
$default_color: Default color specification in the form of a string (e.g. "red"), an RGB
triple (e.g. 255,0,0 for red), or a variable which has been set to a color specification.
Examples
$pref_color = get
$pref_color = get
$default_color
$pref_color = get
$pref_color = get
100,203,240
$pref_color = get
$pref_color = get
preference “my_color_pref” $default_color
preference “my_color_pref” colorval
preference “my_color_pref” colorval “green”
preference “my_color_pref” colorval
preference “my_color_pref” 100 203 240
preference “my_color_pref” 100,203,240
get surface description
Gets the current or specified surface description.
Syntax: get surface|$srf description
Examples
$desc = get surface description
$desc = get $srf1 description
get surface layer count
Gets the number of layers in the current or specified surface.
Syntax: get surface|$srf layer count
Examples
$layers = get surface layer count
$layers = get $srf layer count
get transform (limits)
Gets the current or specified transform’s limits. Returns a number.
Syntax: get transform|$tra input|output min|max
Example
$inmax = get transform input max
Scripting reference
325
get transform type
Gets the current or specified transform type. Returns linear, exp, log or hist.
Syntax: get transform|$tra type
Example
$trantype = get transform type
get (algorithm) view mode
Gets the view mode of the current or specified algorithm.
Syntax: get [$alg] view mode
Example
$vmode = get view mode
get (ER Mapper) version
Returns the ER Mapper version number as a string or as a number.
Syntax: get version_string|version_number
Examples
$version_string = get version_string# returns “5.7”
getenv (environment variable)
Get the given environment variable. This is from the current environment within ER
Mapper.
Syntax: getenv $envname
$envname: String with name of environment variable
Examples
$machine_type = getenv “ERM_MACHINE_TYPE”
$println “ERMSCRIPTS =” + getenv “ERMSCRIPTS
go algorithm
Runs the current or specified algorithm. This causes histograms etc. to be updated.
Syntax: go algorithm|$alg [width height][match]
width height: Resolution at which to run algorithm (default 400 400)
match: If specified, runs a histogram match.
Examples
go
go
go
go
326
algorithm
algorithm 50 50
$alg1 100 100
algorithm 400 400 match
Scripting reference
go background window
Runs the algorithm in the current or specified window as a background task.; i.e
performs a non-blocking go on the window.
Syntax: go background window|$win
Examples
go background window
go background $win
go window
Runs the algorithm in the current or specified window.
Syntax: go window|$win
Examples
go window
go $win
layer active
Checks whether the current layer is active, and returns TRUE (1) for active and FALSE
(0) for inactive
Syntax: layer active
Examples
$layer_is_on = layer active
layer2 = layer1
Assigns specified layer (e.g. $lay1) to another variable (e.g. $lay2)
$lay2 and $lay1 refer to the same object, so deleting $lay1 will invalidate
$lay2. Use copy or duplicate layer to have different objects.
Syntax: $lay2 = $lay1
Example
$lay2 = $lay1
Scripting reference
327
listdir
Lists the contents of the specified directory into an array, with each element being one
file. If a recursive listing is made, then the resultant strings will contain the full path,
otherwise they will just be the filename.
Syntax: listdir $directory [$extension] [recursive]
$directory: String defining the directory to list
$extension: Optional string limiting the list to files with a specific extension (eg.
"*.ers")
recursive: Specify this keyword to descend recursively into sub-directories, and list all
files in the directory tree. This returns filenames with their full path.
Examples
$array = listdir “e:\images” “.ers” recursive
load algorithm
Loads the given algorithm. Sets the current algorithm pointer to point to it. Sets
$ERROR to 1 if it fails; otherwise 0.
Syntax: load algorithm $name
$name: Algorithm filename; e.g. myalg.alg. Must be specified relative to the current
directory or include the absolute path.
Examples
$template_alg_name = “c:\Program Files\ERDAS\ERDAS ER Mapper
7.2\examples\templates\some.alg”
$template_alg_name = load algorithm $template_alg_name
$myfile = “..\..\examples\tutorial\my.alg”
load algorithm $myfile
load filter (filename)
Loads the current or specified filter from the given (.ker) file. The file name must
include the absolute or relative path.
Syntax: load filter|$fil $finame
$fname: String with path and name of filter (.ker) file
Examples
$finame = “filters\myfilter.ker”
load filter $finame
load $fil “filters\myfilter.ker”
328
Scripting reference
load formula (filename)
Loads the current or specified formula file.
Syntax: load formula|$for from $foname
$foname: String, with path and name of formula (.frm) file
Examples
load formula from “ratio\clay_ratio.frm”
$for = load formula from “ratio\clay_ratio.frm”
load layer formula (filename)
Loads the formula file into the current or specified layer’s formula.
Syntax: load layer|$lay formula $foname
$foname: String, with formula filename (.frm) and path.
Example
$form = “ratio\clay_ratio.frm”
load $layer1 formula $form
match transform [to $layer]
Matches the output transforms of all layers to the current or specified layer in the same
surface.
The algorithm must already contain output transforms for the layers being matched.
Use the slower go algorithm match command if the transforms do not exist.
Syntax: match transform [to $layer]
Examples
$temp_layer = first active raster layer
match transform to $temp_layer
first active raster layer
match transform
move layer
Moves the current or specified layer within the current surface to the given position
within its surface.
Syntax: move layer|$lay [to] up|down|top|bottom
Examples
move layer to top
move $layer up
Scripting reference
329
move surface
Moves the current surface within the current algorithm.
Syntax: move surface up|down|top|bottom
Example
move surface bottom
new algorithm
Creates a new (empty) algorithm. This will have 1 pseudocolor layer. The current
algorithm pointer is updated to point to the new algorithm
Syntax: new algorithm
Examples
new algorithm
$alg = new algorithm
new filter
Creates a new filter, but does not add it to any layer.
Syntax: new $ftype|convolution|threshold|user filter
$ftype Filter type variable: value can be convolution, threshold or user.
Example
$fil1 = new convolution filter
new formula
Creates a new formula.
Syntax: new formula
Example
$for1 = new formula
330
Scripting reference
new layer
Creates a new layer of the given type. This creates a floating layer which does not
belong to any surface in any algorithm. To add it to a surface use add layer. This could
be useful if you want to create a layer and duplicate it and change the processing
before adding it.
Syntax: new $layer_type|pseudocolor|red|green|blue|hue| saturation|
intensity|height|classification| classdisplay|link layer
$layer_type: Layer type variable: see “Variables” for allowed values.
Examples
$ltype = height
new $ltype layer
new pseudocolor layer
$new_layer = new pseudocolor layer
new surface
Creates a new surface but does not add it to any algorithm.
Syntax: new surface
Examples
new surface
$add_surface = new surface
new transform
Creates a new transform which then becomes the current transform.
Syntax: new $ttype|linear|exp|log|hist transform
$ttype: Transform type variable: value can be linear, exp, log or hist
Examples
new linear transform
%tran2 = new linear transform
new window
Opens a new image window, with a default algorithm. The current window pointer
points to the new window. The current algorithm pointer points to the new algorithm.
You can specify the position and size of the window.
Syntax: new window [x y w h]
x, y: The x,y coordinate of the top left corner of the window in screen pixels.
w, h: The width and height of the window in screen pixels.
Examples
new window
$win = new window 0 0 600 600
new window $Xoffset $Yoffset $windowwidth $windowheight
Scripting reference
331
next [active][raster|vector] layer (type)
Moves the pointer to the next layer of the type specified.With layers there are the
additional keywords ‘next’ and ‘active’.
Syntax: next [active][raster|vector] [$layer_type] layer
$layer_type: Layer type variable: see “Variables” for allowed values.
Examples
next
next
next
next
next
layer
active layer
active raster layer
active vector layer
red layer
open status (dialog)
Creates (if necessary) and opens the status dialog. This is useful for when the user has
pressed the close button on the status dialog. If "title" is included it is used as the title
of the progress dialog.
The wizard GUI may have a button labelled Status.
Syntax: open status ["title"]
"title": The text which appears in the title bar of the status dialog box.
Example
...
ask action "Status" goto OpenStatus
...
OpenStatus:
open status
goto wizard_page_1
open window
Open the designated dialog box on screen. If the dialog box is iconised, it will be uniconised.
Syntax: open main|algorithm|transform|filter|formula| sunangle|page
setup|annotation|defaults|preferences|
geoposition|processinfo|datasetinfo|scattergram|
traverse|realtime3d|job|profile|cell coordinate window
Example
open sunangle window
332
Scripting reference
print
Write to an output dialog (default) or file without a Carriage Return or Line Feed.
Syntax: print “String”|Number|$var
$var: Variable with string or number. By default, numbers are printed to 6 decimal
places.
The print and println commands write to an output dialog by default. Alternatively, you
can print out to a file using:
set output to $filename
The print or println commands in a batch script after this set command will create the
file if it doesn’t already exist and write the output to the end of the file.
Example
$text=”Hello World”
print $text
print “Hello World”
println
Write to an output dialog (default) or file with a Carriage Return or Line Feed.
Syntax: println “String”|Number|$var
$var: Variable with string or number. By default, numbers are printed to 6 decimal
places.
The print and println commands write to an output dialog by default. Alternatively, you
can print out to a file using:
set output to $filename
The print or println commands in a batch script after this set command will create the
file if it doesn’t already exist and write the output to the end of the file.
Example
$text=”Hello World”
println $text
println “Hello World”
Scripting reference
333
save algorithm
Saves the current or specified algorithm with the given name. Sets $ERROR to 1 if
fails; otherwise 0.
Syntax: save algorithm|$alg $name
$name: Algorithm filename; e.g. myalg.alg. Must be specified relative to the current
directory or include the absolute path.
Examples
$alg_name = “c:\Program Files\ERDAS\ERDAS ER Mapper
7.2\examples\templates\some.alg”
save algorithm $alg_name
save $alg $alg_name
save algorithm as dataset
Saves the current or specified algorithm as a dataset, with the name stored in the
variable $dsname. If the optional parameters are not set, the default values which
would display in the Save as Dataset dialog will be used.
Syntax: save algorithm|$alg as dataset $dsname [$celltype $null_value
$nr_cells $nr_lines]
$dsname: String representing the path and name of dataset (.ers) file.
$cell_type: Cell type variable: value can be uint8, uint16, uint32, int8, int16, int32,
ieee4 or ieee8. e.g $cell_type = uint16 (not “uint16”)
$null_value: String representing the null_value to be used. It may be set to “none”.
$nr_cells: Number representing the number of columns of the image to include.
$nr_lines: Number representing the number of rows of the image to include.
Examples
save $alg as dataset $dsname
$celltype = u16int
save $alg as dataset $dsname $celltype $null_value $nr_cells
$nr_lines
save as dataset $dsname
save algorithm as dataset $dsname $celltype $null_value
$nr_cells $nr_lines
save $alg as dataset $dsname $celltype "none" $nr_cells
$nr_lines
334
Scripting reference
save algorithm as virtual dataset
Saves the current or specified algorithm as a virtual dataset with the given name. Sets
$ERROR to 1 if it fails; otherwise 0.
Syntax: save algorithm|$alg as virtual dataset $name
$name: Virtual dataset filename; e.g. myvds.ers. Must be specified relative to the
current directory or include the absolute path.
Examples
$vds_name = “c:\Program Files\ERDAS\ERDAS ER Mapper
7.2\examples\tutorial\somevds.ers”
save algorithm as virtual dataset $vds_name
save $alg as virtual dataset $vds_name
save filter (filename)
Saves the current or specified filter to the given (.ker) file.
Syntax: save filter|$fil $finame
$fname: String with path and name of filter (.ker) file
Example
$finame = “filters\myfilter.ker”
save filter $finame
save formula (filename)
Saves the current or specified formula to the formula file.
Syntax: save formula|$for to $foname
$foname: String, with path and name of formula (.frm) file
Example
save formula to “ratio\clay_ratio.frm”
save layer formula (filename)
Saves the current or specified layer’s formula to the formula file.
Syntax: save layer|$lay formula $foname
$foname: String with formula filename (.frm) and path.
Example
save $layer1 formula $form
Scripting reference
335
say status
Updates the status dialog with a message (if string) or updates the percent done gauge
to number (between 0 and 100%) or both.
Syntax: say status $number|$string
say status $number $string
$number: Number, representing percentage done
$string: String with status message
Examples
$percent = 80
say status $percent”Opening image window\n”
say status 100 “Finished”
say warning
Opens an ER Mapper warning dialog box
Syntax: say warning "text"
Example
checkdataset:
if ($filename!= "") then goto DatasetOK
say warning "Please enter a filename"
goto wizard_page_1
DatasetOK:
#carry on
select algorithm
Changes the current algorithm pointer to point to the specified algorithm.
Syntax: select $alg
Examples
select $window_alg
select filter
Sets the current filter to the specified filter.
Syntax: select $fil
Example
select $fil
336
Scripting reference
select formula
Sets the current formula to the specified formula.
Syntax: select $for
Example
select $for1
select layer
Sets the current layer pointer to point to the specified layer.
Syntax: select $lay
Example
select $layer1
select surface
Selects the given surface and makes it the current surface.
Syntax: select $srf
Example
select $window_surface
select transform
Sets the current transform to the specified transform.
Syntax: select $tra
Example
select $trans1
select window
Updates the current window pointer to point to the given window.
Syntax: select $win
Example
select $win
set (formula) input to band
Sets the current formula input to the image band given.
Syntax: set input $n1 to band $n2
$n1 $n2: Numbers, representing input and band numbers
Example
set input 1 to band 1
Scripting reference
337
set (page) contents bottomright from topleft
Calculates and sets the bottom right contents extents coordinate, based on the topleft
coordinate, page size, borders, and scale. This functionality makes the implementation
of map templates much easier because you do not need to change the page layout to
accommodate a different image.
Syntax: set [$alg] contents bottomright from topleft
Example
set $alg contents bottomright from topleft
set (page) contents extents to algorithm extents
Set the contents extents to the algorithm extents (where algorithm is the current
algorithm). This is equivalent to the "Snapshot" button on the Page Setup dialogue.
Syntax: set contents extents to [algorithm|$alg] extents
Example
set contents extents to $alg extents
set (page) contents topleft|bottomright
Sets the page contents extents coordinates to that specified by $value.
Syntax: set [$alg] contents topleft|bottomright northings|latitude|meters_y
[to] $value
set [$alg] contents topleft|bottomright eastings|longitude|meters_x [to] $value
$value: Number, representing extent value
Example
set $alg contents topleft eastings to $template_tl_e_extent
set algorithm coordsys changeable to (flag)
By default, when a layer is added to an algorithm or the data source of an existing
layer in the algorithm is changed, the algorithm's coordinate system will change to the
coordinate system of the layer's data source when the coordinate system of the layer's
datasource is not the same as the algorithm's coordinate system and not able to be
reprojected on the fly to the algorithm's coordinate system.
Calling this command with the flag set to FALSE will prevent the algorithm coordinate
system changing when a layer is added to an algorithm or the data source of an
existing layer in the algorithm is changed.
Syntax: set algorithm coordsys changeable to true|false
Example
set $alg coordsys changeable to true
set algorithm coordsys changeable to false
338
Scripting reference
set page autovary_value
This can be used to calculate one of the page setup variables based on the Constraints
setting. For example:
•
When the constraint is "Fixed Page: Extents from Zoom", this command
sets the scale to the largest that will fit on the page.
•
When the constraint is "Auto Vary: Page", this command sets the page size
to whatever is needed to fit in the desired scale and borders.
•
When the constraint is "Auto Vary: Borders", this command sets the
bottom and/or right border sizes to whatever is needed to accommodate
the specified scale and page size.
•
When the constraint is "Auto Vary: Scale", this command sets the scale to
whatever is needed to create a map with the specified page and border
sizes.
Syntax: set [$alg] page autovary_value
Example
set page autovary_value
set algorithm background (color)
Changes the algorithm’s background color to the given RGB values or to a value
specified by a variable.
Syntax: set algorithm|$alg background to $red $green $blue
set [algorithm|$alg] background to colorval $colorvariable
$red $green $blue: RGB numeric values for the required color.
$colorvariable: Color specification in the form of a string (e.g. "red"), an RGB triple
(e.g. 255,0,0 for red), or a variable which has been set to a color specification.
Examples
set algorithm background to 250 245 50
$red = 200
$green = 150
$blue = 30
set $alg background to $red $green $blue
set algorithm background to colorval 250 245 50
set background to color “red”
$background_color = “white”
set $alg background to colorval $background_color
Scripting reference
339
set algorithm coordsys
Sets the algorithm’s coordinate system type to the given type.
Syntax: set algorithm|$alg coordsys to $csys|raw|en|ll
$csys: Coordsys type variable: Value can be raw, en or ll
Examples
$csystem = en
set algorithm coordsys to $csystem
set $alg coordsys to en
set algorithm datum|projection
Sets the algorithm’s datum or projection to the given type. This will cause layers of an
incompatible type to be turned off within the algorithm.
Syntax: set algorithm|$alg datum to $datumname
set algorithm|$alg projection to $projname
$datumname: String representing required datum
$projname: String representing required projection.
Examples
$datum = “NAD27”
set algorithm datum to $datum
set algorithm datum to “NAD27”
set $alg projection to “NUTM11”
set algorithm description
Changes the current or specified algorithm description to the given text.
Syntax: set algorithm|$alg description to $text
$text: Algorithm description text string
Examples
$text = “This algorithm”
set $alg description to $text
set algorithm description to "Pseudocolor Aspect"
340
Scripting reference
set algorithm lut (color table)
Changes the pseudocolor LUT for the first surface in the algorithm to the given lut file.
Syntax: set algorithm|$alg lut [to] $lutname
$lutname: String representing color lookup table filename. It should be within the
ERMAPPER\lut directory and specified within quotes but without the file extension.
Examples
$lut = “greyscale”
set $alg lut to $lut
set algorithm lut to "greyscale"
set algorithm mode
Changes the processing mode for the first surface in the algorithm to the given mode.
Syntax: set algorithm|$alg mode to $mode|pseudo|rgb|hsi
$mode: String variable representing required mode, “pseudo”, “rgb” or “hsi”
Examples
set algorithm mode to rgb
$alg_mode = “hsi”
set $alg mode to $alg_mode
set algorithm mosaic type
Sets the mosaic type (where different datasets overlay) to the given type. Overlay
overwrites earlier layers with latter ones; Feather blends the border.
Syntax: set algorithm|$alg mosaic type to $mtype|overlay|feather
$mtype: Mosaic type variable: overlay or feather
Examples
$mtype = feather
set algorithm mosaic type $mtype
set algorithm mosaic type to feather
set algorithm supersample type
Sets the current or specified algorithm supersample type.
Syntax: set algorithm|$alg supersample type to $supertype|nearest|bilinear
$supertype: SuperSample type variable: value can be nearest or bilinear
Examples
$supertype = bilinear
set algorithm supersample type to $supertype
set $alg supersample type to nearest
Scripting reference
341
set algorithm topleft|bottomright (extents)
Sets the current or specified algorithm topleft and bottomright extent fields in
easting/northing, latitude/longitude or raw coordinate systems.
Syntax: set algorithm|$alg topleft|bottomright eastings|longitude|meters_x
to $number
set algorithm|$alg topleft|bottomright northings|latitude|meters_y to
$number
$number: Number, representing extents value.
Examples
$tl_east = 475912.476235
set algorithm topleft eastings to $tl_east
set algorithm topleft eastings to 475912.476235
set algorithm units|rotation
Sets the units or rotation to the given value.
Syntax: set algorithm|$alg units to $units
set algorithm|$alg rotation to $value
$units: String representing units: “meters”, “feet”, “yards”, “links”, “chains”, “roods”,
“brealy units” or “natural”
$value: Numerical value representing rotation in degrees
Examples
$units = “natural”
set algorithm units to $units
set $alg units to “natural”
$rotate = 0
set $alg rotation to $rotate
set algorithm rotation to 0
set filter description
Changes the current or specified filter description to the given text.
Syntax: set filter|$fil description to $text
$text: Filter description text string
Examples
$text = “This filter”
set $fil1 description to $text
set filter description to "High_pass"
342
Scripting reference
set filter matrix (element)
Sets an element of the current or specified filter matrix. Valid only on convolution and
threshold filters.
Syntax: set filter|$fil matrix $x $y $number
$x $y: Numbers, representing coordinates of element in matrix
$number: Number, value to set in element
Examples
$number = 4
set filter matrix 1 1 $number
set filter matrix 1 1 1
set (usercode) filter params
Set the current or specified user filter parameter string. Valid only on usercode filters.
Syntax: set filter|$fil params to $paramstring
$paramstring: String, with filter parameters
Example
$params = “$SYS_STDOUT”
set filter params to $params
set filter postsampled (flag)
Sets whether the current or specified filter can process resampled data, or source data.
Syntax: set filter|$fil postsampled true|falses
Example
$set filter postsampled false
set filter rows|cols
Sets the number or rows/columns for the current or specified filter to $number.
$number must be odd.
Syntax: set filter|$fil rows|cols [to] $number
$number: Number, representing number of rows or columns. Must be odd
Example
$filrows = 3
set filter rows to $filrows
set $fil1 cols to 3
Scripting reference
343
set filter scale|threshold
Sets the scale or threshold for the current or specified filter. Valid only on convolution
and threshold filters.
Syntax: set filter|$fil scale|threshold [to] $value
$value: Number, representing scale or threshold value
Example
$value = 1
set filter scale to $value
set filter scale to 1
set filter type
Sets the filter type of the current or specified filter.
Syntax: set filter|$fil type [to] $ftype|convolution|threshold|user
$ftype: Filter type variable: value can be convolution, threshold or user.
Example
$filtype = threshold
set filter type to $filtype
set $fil1 type to threshold
set (usercode) filter userfile (filename)
Sets the current or specified user filter source file, for a C usercode filter. Valid only on
usercode filters.
Syntax: set filter|$fil userfile [to] $filename
$filename: String with path and name of filter source (.c) file
Example
$fname = “usercode\kernel\c\newfilter.c”
set filter userfile to $fname
set $fil2 userfile to “usercode\kernel\c\newfilter.c”
set (usercode) filter userfunc (filename)
Sets the current or specified user filter function (.dll) name. Valid only on usercode
filters.
Syntax: set filter|$fil userfunc to $funcname
$funcname: String with path and name of filter function (.dll) file
Examples
$funcname = “usercode\kernel\c\win32\newfilter.dll”
set filter userfunc to $funcname
set $fil2 userfunc to “usercode\kernel\c\win32\newfilter.dll”
344
Scripting reference
set formula
Sets the current or specified formula ($formula is a string).
Syntax: set formula|$for to $formula
$formula: String, with formula
Examples
$formula = “i1 + i2”
set formula to $formula
set $for1 to “i1 + i2”
set layer azimuth|elevation
Sets the sun shade azimuth/elevation to the given value in degrees.
Syntax: set layer|$lay azimuth|elevation to $deg
$deg: Number, representing azimuth or elevation in degrees.
Example
set layer azimuth to 45
set layer color
Sets the current or specified layer color to the given RGB or color values. Valid only on
link layers.
Syntax: set layer|$lay color to $red $green $blue
set layer color to colorval $colorvariable
$red $green $blue: RGB numeric values for the required color.
$colorvariable: Color specification in the form of a string (e.g. "red"), an RGB triple
(e.g. 255,0,0 for red), or a variable which has been set to a color specification.
Examples
set layer color to 1.0 1.0 1.0
set $lay1 color to 1.0,1.0,1.0
$lay_color = “red”
set layer color to colorval $lay_color
set $layer1 color to colorval “red”
set layer color to colorval 123,155,100
Scripting reference
345
set layer dataset (filename)
Sets the image file name for the current or specified layer to $dsname.
Syntax: set layer|$lay dataset to $dsname
$dsname: String specifying the image name (within quotes), including the file
extension. The path should be either absolute or relative to the current directory
Example
$dsname = “examples\Shared_Data\testlayer.ers”
set $layer1 dataset to $dsname
set layer description
Changes the layer description to the text given.
Syntax: set layer|$lay description to $text
$text: String with layer description
Examples
$lay_desc = “First red”
set layer description to $lay_desc
set $layer1 description to “Second red”
set layer editable (flag)
Sets the editable flag for current or specified layer. Valid only for link layers.
Syntax: set layer|$lay editable [to] true|false
Example
set layer editable to true
set layer edit|init program (name)
Sets the current or specified layer’s edit/init program to the given name. Valid only on
link layers.
Syntax: set layer|$lay edit|init program to $fname
$fname: String, with program name.
Examples
set layer edit program to “erm_link”
set layer init program to “erminit_oracle”
346
Scripting reference
set layer formula
Sets the current or specified layer formula.
Syntax: set layer|$lay formula to $formula
$formula: String, with formula.
Examples
$form = “i1 + i2”
set layer formula to $form
set layer formula to "i1 + i2"
set layer input to band
Sets the designated layer input to the specified band number
Syntax: set layer|$lay input $n1 to band $n2
$n1 $n2: Number
Examples
set layer input 1 to band 1
set layer $input_no to band $band_no
set layer link extension
Sets the link file extension of the current or specified layer to the given string.
Syntax: set layer link extension to $extent
$extent: String with link extension.This field can take three forms:
"": no extension.
".erv": a normal file extension.
"erv_chooser": a program to generate a list of choices from which the user must
choose one.
Example
set layer link extension to “.erv”
set layer link type to monocolour|truecolour
Sets the link type of the current or specified layer to monocolour or truecolour. Valid
only on link layers. Note the English spelling of ‘colour’.
Syntax: set layer|$lay link type to monocolour|truecolour
Example
set layer link type to truecolour
Scripting reference
347
set layer shading on|off
Turns sunshading on/off for the current or specified layer.
Syntax: set layer|$lay shading on|off
Example
set layer shading on
set layer type
Changes the current or specified layer to the given type.
Syntax: set layer|$lay type to
$stype|pseudocolor|red|green|blue|hue|saturation|intensity|height|classifi
cation|classdisplay|link
$stype: Layer type variable: see “Variables” for allowed values.
Examples
$lay_type = hue
set layer type to $lay_type
set $layer1 type to green
set page center horizontal|vertical
Centers the contents of the page horizontally or vertically.
Syntax: set [$alg] page center horizontal|vertical
Example
set $alg page center horizontal
set page constraints
Sets the page constraints of the current or specified algorithm.
Syntax: set [$alg] page constraints to $constr|zoom|page|border|scale
$constr: Constraints variable: value can be zoom, page, border or scale
Examples
$page_constraint = border
set $alg page constraints to $page_constraint
set page constraints to scale
set page extents from contents
Calculates and sets the page extents of the algorithm based on the contents extents,
the borders, and the scale.
Syntax: set [$alg] page extents from contents
Example
set $alg page extents from contents
348
Scripting reference
set page scale
Sets the page scale to a specific number or the maximum scale possible.
Syntax: set [$alg] page scale to $scale|max
$scale: Number, representing scale value
Examples
$page_scale = 1000
set $alg page scale to $page_scale
set $alg page scale to max
set page scale to 1000
set page size
Sets the page size of the current or specified algorithm.
Syntax: set [$alg] page size to $size
$size: String with standard page size: value can be one of the following:
•
"US Letter”, "US Letter - landscape",
•
"US Legal”, "US Legal - landscape",
•
“A0”, "A0 - landscape",
•
“A1”, "A1 - landscape",
•
“A2”, "A2 - landscape",
•
“A3”, "A3 - landscape",
•
“A4”, "A4 - landscape",
•
“A5”, "A5 - landscape",
•
“A6”, "A6 - landscape",
•
“B3”, "B3 - landscape",
•
“B4”, "B4 - landscape",
•
“B5” or "B5 - landscape"
Examples
$page_size = “US Letter”
set $alg page size to $page_size
set page size to “US Letter”
Scripting reference
349
set page topleft|bottomright (extents)
Sets the page extents coordinates to that specified in the variable $value.
Syntax: set [$alg] page topleft|bottomright northings|latitude|meters_y [to]
$value
set [$alg] page topleft|bottomright eastings|longitude| meters_x [to] $value
$value: Number, representing extent value
Example
set $alg page topleft eastings to $tl_e_extent
set page top|bottom|left|right border
Sets the page borders.
Syntax: set [$alg] page top|bottom|left|right border to $number mm|inches
$number: Number, representing size in inches or millimeters
Examples
$page_top = 1.0
set $alg page top border to $page_top inches
set page top border to 1.0 inches
set (algorithm) page view mode
Sets the page view mode of the current or specified algorithm to normal or layout.
Syntax: set [$alg] page view mode to $pvmode|normal|layout
$pvmode: Page view mode variable: value can be normal or layout
Example
set $alg page view mode to layout
set page width|height
Sets the specified page size parameter of the current or specified algorithm.
Syntax: set [$alg] page width|height [to] $number inches|mm
$number: Number, representing size in inches or millimeters
Examples
$page_width = 5
set $alg page width to $page_width inches
set $alg page width to 5 inches
350
Scripting reference
set pointer mode
Sets the mouse pointer to the specified mode: zoom, zoombox, roam(hand) or pointer.
Syntax: set pointer mode to zoom|zoombox|roam|pointer
Examples
set pointer mode to zoom
set pointer mode to zoombox
set pointer mode to roam
set preference
Adds or updates the preference ‘name’ entry in the user’s preference file as a string or
number.
Syntax: set preference "name" [to]
$string|$number[boolean|integer|double]
“name”: String with name of entry in preference file. The recommended format is
“Class:Name:Variable” .
$string: String with value for entry
$number: Number with value for entry
Examples
set preference “Wizard:Image:MainChoice” $page_main_choice
set preference “MACHINECONFIG_HAS-RUN” TRUE boolean
set preference (color)
Sets the color preference entry in the user’s preference file.
Syntax: set preference "colorname" to $red $green $blue
set preference "colorname" to colorval $color|$red,$green,$blue
“colorname”: Color preference entry name
$red $green $blue: RGB numeric values for the required color.
$color: Color specification in the form of a string (e.g. "red"), an RGB triple (e.g.
255,0,0 for red), or a variable which has been set to a color specification.
Examples
set
set
set
set
set
Scripting reference
preference
preference
preference
preference
preference
“my_color_pref”
“my_color_pref”
“my_color_pref”
“my_color_pref”
“my_color_pref”
to
to
to
to
to
155 203 200
155,203,200
colorval $new_color
colorval “green”
155,203,200
351
set surface description
Changes the current or specified surface description to the given text.
Syntax: set surface|$srf description to $text
$text: Surface description text string
Examples
$text = “This surface”
set $srf1 description to $text
set surface description to "Main surface"
set surface lut (color table)
Sets the Color Table for the current surface.
Syntax: set surface lut [to] $lut
$lut: String representing color lookup table filename. It should be within the
%ERMAPPER%\lut directory and specified within quotes but without the file extension.
Examples
set surface lut to $new_lut
set surface lut to “pseudocolor”
set surface mode (color)
Sets the color mode for the current surface.
Syntax: set surface mode [to] $surface_mode|rgb|hsi|pseudo
$surface_mode: Mode type variable: value can be rgb, hsi or pseudocolor (or
pseudo)
Examples
$new_mode = rgb
set surface mode to $new_mode
set surface mode to pseudo
set surface name
Sets the current surface name to the given name.
Syntax: set surface name [to] $string
$string: String with surface name.
Examples
$surface_name = “Top surface”
set surface name to $surface_name
set surface name to “Bottom surface”
352
Scripting reference
set surface zscale|zoffset|transparency
Sets the Z Scale, Z Offset or transparency of the current surface to $value.
Syntax: set surface zscale|zoffset|transparency [to] $value
$value: Number representing required value.
Example
set surface transparency to 20
set transform clip
Applies a clip of $pct percent to the current or specified transform. If $pct is not
specified 99.0 is used.
Syntax: set transform|$tra clip [to $pct]
$pct: Number, representing percentage clip
Example
set transform clip to 90
set transform input|output min|max (limits)
Sets the current or specified transform input/output limits.
Syntax: set transform|$tra input|output min|max to $number
$number: Number, representing input/output limits
Examples
$inmax = 361
set transform input max to $inmax
set transform input max to 7
set transform limits (actual or percentage)
Sets the current or specified transform limits to $percent or actual.
Syntax: set transform|$tra limits to actual|$percent
$percent: Number, representing percentage
Example
set transform limits to actual
set transform limits to 50
Scripting reference
353
set transform to gaussian equalize
Applies a gaussian equalize operation to the current or specified transform. If the
gaussian envelope halfwidth is not specified a halfwidth of 3 standard deviations is
used.
Syntax: set transform|$tra to gaussian equalize [$halfwidth]
$halfwidth: Number, representing envelope halfwidth in standard deviations
Example
set transform to gaussian equalize
set transform to histogram equalize
Applies a histogram equalize operation to the current or specified transform.
Syntax: set transform|$tra to histogram equalize
Example
set transform to histogram equalize
set transform type
Sets the current or specified transform type.
Syntax: set transform|$tra type to $ttype|linear|exp|log|hist
$ttype: Transform type variable: value can be linear, exp, log or hist
Example
set transform type to linear
set view mode
Sets the view mode of the current or specified algorithm to 2D, 3D perspective or 3D
flythru.
Syntax: set [$alg] view mode to $vmode|2d|perspective|flythru
$vmode: ViewMode variable: value can be 2d, perspective or flythru
Example
set $alg view mode to perspective
set window geolink mode
Various geolink functionality.
Syntax: set window|$win geolink mode to none|window|screen| overview
Example
set window geolink mode to window
354
Scripting reference
setenv (environment variable)
Set the given environment.
This changes the current environment within ER Mapper.
Syntax: setenv $envname $value
$envname: String with name of environment variable
$value: String with value to set the environment variable to
Example
setenv “ERM_MACHINE_TYPE” “win32”
show image (in container)
Displays the specified image in the container.
Syntax: show image $filename
$filename: String with path and name of image file. path name can be absolute or
relative to the %ERMAPPER%\icons directory
Examples
$image = “standard_icons\image_main”
show image $image
show image “standard_icons\image_main”
Scripting reference
355
split string
Split the given string into an array of substrings at the given token. The array is
terminated by an empty string. Specifying empty double quotes as the split character
splits a string into an array of single letter elements.
$string = "first second third"
$array = split $string at " "
$array[1] -> "first"
$array[2] -> "second"
$array[3] -> "third"
$array[4] -> "" - terminator
$array[5] -> invalid
The first array index will always be a 1.
Syntax: split $string at $token
$string: String to be split
$token: String with character where string must be split
Example
$filenames = split $string at “\n”
surface active
Checks whether the current surface is active, and returns TRUE (1) for active, and
FALSE (0) for inactive.
Syntax: surface active
Examples
$surface_is_on = surface active
system command
Executes a system command from within the script.
Syntax: system $command [status [“Title”]]
$command: System command to be executed“&” at the end of the command will
make it run in the background.
status: Optional status dialog box
“Title”: String with status box title (optional)
Examples
$cmd = "ermbalance calcclip" + $balance_file_spec + “&”
system $cmd
system "ermbalance calcclip" + $balance_file_spec + “&”
356
Scripting reference
transform2 = transform1
Assign specified transform (e.g. $tra1) to another variable (e.g. $tra2).
$tra2 and $tra1 refer to the same object, so deleting $tra1 will invalidate
$tra2. Use the copy or duplicate transform command to create a separate
object.
Syntax: $tra2 = $tra1
Example
$tra2 = $tra1
turn layer on|off
Turns the current or specified layer on or off.
Syntax: turn layer|$lay on|off
Example
turn $layer1 on
turn surface on|off
Enables/Disables the current surface.
Syntax: turn surface on|off
Example
turn surface on
window2 = window1
Copies the window reference from win1 to win2, that is, both $win1 and $win2 point to
the same object.
Syntax: $win2 = $win1
Wizard close
The "Wizard Close" command is needed because you often can't automatically close a
wizard when the user presses the Finish button. You usually need to check the
necessary parameters have been entered. In this case you would check everything is
fine, and if it is, close the wizard using the "Wizard Close" command, and if it is not, go
back to the appropriate page of the wizard. You can use Exit to exit a script and close
down the wizard automatically but this is not recommended.
Syntax: Wizard close [name]
name: If you don’t specify a Name, all wizards are closed. If you specify a Name, then
the named wizard, and all sibling wizards created after it, are closed.
Scripting reference
357
WizardPage begin|end
This marks the beginning and end of a new wizard page. ‘WizardName’ is the name of
the wizard within the script. If it is a different name from the previous Wizard Block a
new wizard window is drawn; if it is the same as the name in the previous Wizard
Block, the previous window is redrawn with the new contents. WizardName is optional
for second and subsequent pages: if omitted it defaults to the name from the previous
Wizard Block.
Syntax: WizardPage begin "WizardName" title “title_text”
..... (container blocks)
WizardPage end
title "title_text": Specifies the title which will appear on the Title Bar of the wizard
page on screen. This should include the name of the Wizard (which indicates what it is
used for), followed by a hyphen and the step number. For example,
title "ClassificationWizard - Step 1 of 4"
container blocks: If no container block is defined a default container block the size of
the whole page will be included.
WizardPage end: Defines the end of the wizard page.
Example
WizardPage begin "WizardName"#title for first page
title "Page1Name" #if a new wizard
container begin "Image"
container information
#usually image info
...
#on first page
container end
container begin "DataEntry"
container information
...
container end
container begin "PageControls"
#control buttons
ask action "< Back"
ask action "Next >" goto label1
ask action "Cancel" close goto label2
container end
wizard close
WizardPage end
zoom
Zoom in or out using specified option.
Syntax: previous zoom
zoom in|out
zoom to all datasets|current datasets|all raster datasets|all vector
datasets|contents extents|page extents|page contents
Examples
previous zoom
zoom in
set pointer mode to roam
zoom to all datasets
zoom to page contents
358
Scripting reference
Sensor Platform Characteristics
This section provides details of various sensor platforms whose data
are supported by ER Mapper.
NOAA
•
SHORT NAME: NOAA_AVHRR
•
PLATFORM: NOAA
•
SENSOR: AVHRR(Advanced Very High Resolution Radiometer)
•
TYPE: Polar orbiting satellite.
•
DESCRIPTION: Designed to provide information for hydrologic,
oceanographic and meteorologic studies, although data provided
by the sensor does find application also to solid earth monitoring.
•
ALTITUDE: 700 - 1500 km
•
REPEAT CYCLE: 2 per day from two satellites
•
GROUND SWATH: 2700 km
•
NADIR RESOLUTION: 1.1 km
•
DYNAMIC RANGE: 10 bit
•
YSPECTRAL BANDS:
Band No.
Wavelength
(µ) microns
Bandwidth
(µ) microns
Central
Wavelength
(µ) microns
1
0.58-0.68
0.1
0.63
2
0.725-1.1
0.375
0.9125
3
3.55-3.93
0.38
3.74
4
10.3-11.3
1.0
10.8
5
11.5- 12.5
1.0
12.0
ERMAPPER SENSORTYPE FILE:
cameras_and_sensors\AVHRR.ers
AVHRR.ers file is as follows:
DatasetHeader Begin
Version = “1.0”
Name = “NOAA (AVHRR) satellite”
DataSetType = ERStorage
DataType = Raster
RasterInfo Begin
Sensor Platform Characteristics
359
CellType = Unsigned8BitInteger
NullCellValue = 0
CellInfo Begin
Xdimension = 1100
Ydimension = 1100
Xoverlap = 0
Yoverlap = 0
CellInfo End
NrOfBands= 5
BandId Begin
Value = “0.63”
Width = 0.1
Units = “um”
BandId End
BandId Begin
Value = “0.9125”
Width = 0.375
Units = “um”
BandId End
BandId Begin
Value = “3.74”
Width = 0.38
Units = “um”
BandId End
BandId Begin
Value = “10.8”
Width = 1.0
Units = “um”
BandId End
BandId Begin
Value = “12.0”
Width = 1.0
Units = “um”
BandId End
RasterInfo End
DatasetHeader End
Geoscan MSS
Mark 2
360
•
SHORT NAME: GEOSCAN_2
•
PLATFORM: Airborne scanner
•
SENSOR: Multi-spectral
•
DESCRIPTION: Has roll, pitch and yaw stabilisation; can record
UTM co-ordinates for each pixel; 6 calibration sources on
scanner; records image data onto optical disk media. Up to 10
bisible/NIR channels selectable from 32 standard detector
intervals between 480-1000 nm, plus 8 MIR channels of equal
width between 2.0 - 2.5 um, plus 6 TIR channels of equal width
between 8.0 - 12.0 um.
Sensor Platform Characteristics
•
MAX FOV(DEGREES): 92.16
•
MAX IFOV(DEGREES: 3 x 2.25
•
DYNAMIC RANGE: 8 or 12 bit (plus 8 bit gain and 8 bit offset)
•
SPECTRAL BANDS: Total of 24 bands. Typical configuration,
below.
Band No.
Bandwidth
(µ) microns
Central
Wavelength
(µ) microns
0.681-0.705
0.705-0.729
0.729-0.752
0.819-0.841
0.862-0.883
0.904-0.926
0.945-0.965
0.042
0.067
0.071
0.024
0.024
0.023
0.022
0.022
0.021
0.020
0.522
0.583
0.645
0.693
0.717
0.740
0.830
0.873
0.915
0.955
1.820-2.260
1.868-2.308
1.912-2.352
1.956-2.396
2.000-2.440
2.044-2.484
2.088-2.528
2.132-2.572
0.044
0.044
0.044
0.044
0.044
0.044
0.044
0.044
2.044
2.088
2.136
2.176
2.220
2.264
2.308
2.352
0.530
0.530
0.530
0.530
0.530
0.530
8.64
9.17
9.70
10.22
10.75
11.28
Wavelength
(µ) microns
VNIR
1
2
3
4
5
6
7
8
9
10
0.550-0.617
SWIR
11
12
13
14
15
16
17
18
TIR
19
20
21
22
23
24
ERMAPPER SENSORTYPE FILE:
cameras_and_sensors\Geoscan.ers
Geoscan2.ers file is shown below.
DatasetHeader Begin
Version = “1.0”
Name = “Geoscan Mark II 24 band scanner”
DataSetType = ERStorage
DataType = Raster
Sensor Platform Characteristics
361
CoordinateSpace Begin
ProjectionType = RAW
CoordinateSystem = RAW
CoordinateSpace End
RasterInfo Begin
CellType = Unsigned8BitInteger
NullCellValue = 0
CellInfo Begin
Xdimension = 3
Ydimension = 3
Xoverlap = 0
Yoverlap = 0
CellInfo End
NrOfCellsPerLine = 1024
NrOfBands = 24
BandId Begin
Value = “0.522”
Width = 0.042
Units = “um”
BandId End
BandId Begin
Value = “0.583”
Width = 0.067
Units = “um”
BandId End
BandId Begin
Value = “0.645”
Width = 0.071
Units = “um”
BandId End
BandId Begin
Value = “0.693”
Width = 0.024
Units = “um”
BandId End
BandId Begin
Value = “0.717”
Width = 0.024
Units = “um”
BandId End
BandId Begin
Value = “0.740”
Width = 0.023
Units = “um”
BandId End
BandId Begin
Value = “0.830”
Width = 0.022
Units = “um”
BandId End
362
Sensor Platform Characteristics
BandId Begin
Value = “0.873”
Width = 0.022
Units = “um”
BandId End
BandId Begin
Value = “0.915”
Width = 0.021
Units = “um”
BandId End
BandId Begin
Value = “0.955”
Width = 0.020
Units = “um”
BandId End
BandId Begin
Value = “2.044”
Width = 0.044
Units = “um”
BandId End
BandId Begin
Value = “2.088”
Width = 0.044
Units = “um”
BandId End
BandId Begin
Value = “2.136”
Width = 0.044
Units = “um”
BandId End
BandId Begin
Value = “2.176”
Width = 0.044
Units = “um”
BandId End
BandId Begin
Value = “2.220”
Width = 0.044
Units = “um”
BandId End
BandId Begin
Value = “2.264”
Width = 0.044
Units = “um”
BandId End
BandId Begin
Value = “2.308”
Width = 0.044
Units = “um”
BandId End
Sensor Platform Characteristics
363
BandId Begin
Value = “2.352”
Width = 0.044
Units = “um”
BandId End
BandId Begin
Value = “8.64”
Width = 0.530
Units = “um”
BandId End
BandId Begin
Value = “9.17”
Width = 0.530
Units = “um”
BandId End
BandId Begin
Value = “9.70”
Width = 0.530
Units = “um”
BandId End
BandId Begin
Value = “10.22”
Width = 0.533
Units = “um”
BandId End
BandId Begin
Value = “10.75”
Width = 0.533
Units = “um”
BandId End
BandId Begin
Value = “11.28”
Width = 0.533
Units = “um”
BandId End
RasterInfo End
DatasetHeader End
IRS-IC
364
•
SHORT NAME: IRS-IC (Indian Remote Sensing Satellite)
•
PLATFORM: IRS-IC satellite
•
SENSOR: There are three sensors, viz. Panchromatic Camera
(PAN), Linear Imaging and Self Scanning Sensor (LISS-III) and
Wide Field Sensor (WiFS)
•
TYPE: Three axis body stabilized satellite.
Sensor Platform Characteristics
•
DESCRIPTION: Provides a systematic and repetitive acquisition
of data of the Earth's surface under nearly constant illumination
conditions.
•
ORBIT: Near polar, sun synchronous; nominal 10:30 am
descending equatorial crossing.
•
ALTITUDE: 817 km
•
PERIOD: 101.35 min
•
REPEAT CYCLE: 14.2 orbits per day over 24 days (341
revolutions)
•
GROUND SWATH: The three sensors collect data with different
swaths:
•
•
Band No.
•
PAN: 70 km
•
WiFS: 148 km
•
LISS-III: 141 km (visible bands) 148 km (SWIR band)
RESOLUTION: PAN: 5.8 m
•
WiFS: 188.3 m
•
LISS-III: 23.5 m (visible bands) 70.5 m (SWIR band)
SPECTRAL BANDS:
Wavelength (µ)
microns
Bandwidth
(µ) microns
Central
Wavelength
(µ) microns
0.5-0.75
0.15
0.575
0.52-0.59 (green)
0.62-0.68 (red)
0.77-0.86 (NIR)
1.55-1.7 (SWIR)
0.07
0.04
0.09
0.15
0.555
0.64
0.815
1.625
0.62-0.68 (red)
0.77-0.86 (NIR)
0.04
0.09
0..64
0.815
PAN
1
LISS-III
1
2
3
4
WiFS
1
2
•
Sensor Platform Characteristics
ERMAPPER SENSORTYPE FILE:Three sensortype files:
•
cameras_and_sensors\IRS-1C_Pan.ers
•
cameras_and_sensors\IRS-1C_WiFS.ers
365
•
cameras_and_sensors\IRS-1C_LISS-3.ers
cameras_and_sensors\IRS-1C_Pan.ers is shown below.
DatasetHeader Begin
Version = "1.0"
Name = "IRS-1C Panchromatic Sensor"
DataSetType = ERStorage
DataType = Raster
RasterInfo Begin
CellType = Unsigned8BitInteger
NullCellValue = 0
CellInfo Begin
Xdimension = 5.8
Ydimension = 5.8
CellInfo End
NrOfBands= 1
BandId Begin
Value = "0.625"
Width = 0.125
Units = "um"
BandId End
RasterInfo End
DatasetHeader End
cameras_and_sensors\IRS-1C_WiFS.ers is shown below.
DatasetHeader Begin
Version = "1.0"
Name = "IRS-1C WiFS sensor"
DataSetType = ERStorage
DataType = Raster
RasterInfo Begin
CellType = Unsigned8BitInteger
NullCellValue = 0
CellInfo Begin
Xdimension = 188.3
Ydimension = 188.3
CellInfo End
NrOfBands= 2
BandId Begin
Value = "0.65"
Width = 0.06
Units = "um"
BandId End
BandId Begin
Value = "0.815"
Width = 0.09
Units = "um"
BandId End
RasterInfo End
366
Sensor Platform Characteristics
DatasetHeader End
cameras_and_sensorsIRS-1C_LISS-3.ers is shown below.
DatasetHeader Begin
Version = "1.0"
Name = "IRS-1C LISS-3 sensor"
DataSetType = ERStorage
DataType = Raster
RasterInfo Begin
CellType = Unsigned8BitInteger
NullCellValue = 0
CellInfo Begin
Xdimension = 23.5
Ydimension = 23.5
CellInfo End
NrOfBands= 4
BandId Begin
Value = "0.555"
Width = 0.07
Units = "um"
BandId End
BandId Begin
Value = "0.65"
Width = 0.06
Units = "um"
BandId End
BandId Begin
Value = "0.815"
Width = 0.09
Units = "um"
BandId End
BandId Begin
Value = "1.625"
Width = 0.075
Units = "um"
BandId End
RasterInfo End
DatasetHeader End
LANDSAT 4 or
LANDSAT MSS
Sensor Platform Characteristics
•
SHORT NAME: Landsat_4 or Landsat_MSS
•
PLATFORM: Landsat
•
SENSOR: Multispectral Scanner (MSS) & Thematic Mapper (TM)
•
TYPE: Second generation earth resources satellite system
•
DESCRIPTION:Spacecraft at lower altitude than first generation,
to assist in achieving higher resolution and to aid shuttle
recovery.
367
•
ORBIT:Near polar, sun synchronous; nominal 9:30 am
descending equatorial crossing.
•
ALTITUDE:705 km
•
PERIOD:98.9 min
•
REPEAT CYCLE:14.56 orbits per day over 16 days (233
revolutions)
•
GROUND SWATH:185 m
•
IFOV81.5 m
•
NADIR RESOLUTION:56 x 56 m (MSS)
•
DYNAMIC RANGE:7 bits (MSS), 6 bits ( MSS 0.8 - 1.1 um), 8 bits
(TM)
•
SPECTRAL BANDS:
Band No.
Wavelength
(µ) microns
Bandwidth
(µ) microns
Central
Wavelength
(µ) microns
0.5-0.6
0.6-0.7
0.7-0.8
0.8-1.1
0.1
0.1
0.1
0.3
0.55
0.65
0.75
0.95
0.45-0.52
0.52-0.60
0.63-0.69
0.76-0.90
1.55-1.75
2.08-2.35
10.4-12.5
0.07
0.08
0.06
0.14
0.2
0.27
2.1
0.485
0.56
0.66
0.83
1.65
2.215
11.45
MSS
1
2
3
4
TM
1
2
3
4
5
7
6
•
ERMAPPER SENSORTYPE FILE:Two sensortype files:
•
cameras_and_sensors\Landsat_4.ers
•
and cameras_and_sensors\Landsat_MSS.ers.
These files are equivalent, they have been so named for
convenience.
cameras_and_sensors\Landsat_4.ers is shown below.
DatasetHeader Begin
Version = “1.0”
Name = “Landsat 4 (MSS) satellite”
368
Sensor Platform Characteristics
DataSetType = ERStorage
DataType = Raster
RasterInfo Begin
CellType = Unsigned8BitInteger
NullCellValue= 0
CellInfo Begin
Xdimension = 81.5
Ydimension = 81.5
Xoverlap = 0
Yoverlap = 0
CellInfo End
NrOfBands= 4
BandId Begin
Value = “0.55”
Width = 0.1
Units = “um”
BandId End
BandId Begin
Value = “0.65”
Width = 0.1
Units = “um”
BandId End
BandId Begin
Value = “0.75”
Width = 0.1
Units = “um”
BandId End
BandId Begin
Value = “0.95”
Width = 0.3
Units = “um”
BandId End
RasterInfo End
DatasetHeader End
LANDSAT 5 or
LANDSAT TM
Sensor Platform Characteristics
•
SHORT NAME: Landsat_5 or Landsat_TM
•
PLATFORM: Landsat
•
SENSOR: Multispectral Scanner (MSS) & Thematic Mapper (TM)
•
TYPE: Second generation earth resources satellite system
•
DESCRIPTION: Spacecraft at lower altitude than first generation,
to assist in achieving higher resolution and to aid shuttle
recovery.
•
ORBIT: Near polar, sun synchronous; nominal 9:30 am
descending equatorial crossing.
369
•
ALTITUDE: 705 km
•
PERIOD: 98.9 min
•
REPEAT CYCLE:14.56 orbits per day over 16 days (233
revolutions)
•
NADIR X OVERLAP:
•
NADIR Y OVERLAP:
•
GROUND SWATH: 185 m
•
IFOV: 82.5 m
•
NADIR RESOLUTION:30 x 30 m (TM), 120 x 120 m (TM 104. 12.5 um)
•
DYNAMIC RANGE:7 bits (MSS), 6 bits ( MSS 0.8 - 1.1 um), 8 bits
(TM)
•
SPECTRAL BANDS:
Band No.
Wavelength
(µ) microns
Bandwidth
(µ) microns
Central
Wavelength
(µ) microns
0.5-0.6
0.6-0.7
0.7-0.8
0.8-1.1
0.1
0.1
0.1
0.3
0.55
0.65
0.75
0.95
0.45-0.52
0.52-0.60
0.63-0.69
0.76-0.90
1.55-1.75
2.08-2.35
10.4-12.5
0.07
0.08
0.06
0.14
0.2
0.27
2.1
0.485
0.56
0.66
0.83
1.65
2.215
1
MSS
1
2
3
4
TM
1
2
3
4
5
7
6
•
ERMAPPER SENSORTYPE FILE: Two sensortype files:
•
cameras_and_sensors\Landsat_5.ers and
•
cameras_and_sensors\ Landsat_TM.ers.
These files are equivalent, they have been so named for
convenience. cameras_and_sensors\Landsat_5.ers is
shown below:
DatasetHeader Begin
Version = “1.0”
370
Sensor Platform Characteristics
Name = “Landsat 5 (TM) satellite”
DataSetType = ERStorage
DataType = Raster
RasterInfo Begin
CellType = Unsigned8BitInteger
NullCellValue= 0
CellInfo Begin
Xdimension = 30.0
Ydimension = 30.0
Xoverlap = 0
Yoverlap = 0
CellInfo End
NrOfBands= 7
BandId Begin
Value = “0.485”
Width = 0.07
Units = “um”
BandId End
BandId Begin
Value = “0.56”
Width = 0.08
Units = “um”
BandId End
BandId Begin
Value = “0.66”
Width = 0.06
Units = “um”
BandId End
BandId Begin
Value = “0.83”
Width = 0.14
Units = “um”
BandId End
BandId Begin
Value = “1.65”
Width = 0.2
Units = “um”
BandId End
BandId Begin
Value = “11.45”
Width = 2.1
Units = “um”
BandId End
BandId Begin
Value = “2.215”
Width = 0.27
Units = “um”
BandId End
RasterInfo End
DatasetHeader End
Sensor Platform Characteristics
371
LANDSAT 7
•
SHORT NAME: Landsat_7
•
PLATFORM: Landsat
•
SENSOR: Enhanced Thematic Mapper (ETM+)
•
TYPE: Third generation earth resources satellite system
•
ORBIT: Near polar, sun synchronous; nominal 10:00 am
descending equatorial crossing.
•
ALTITUDE: 705 km
•
PERIOD: 98.884 min
•
REPEAT CYCLE: 14.56 orbits per day over 16 days (233
revolutions)
•
GROUND SWATH: 185 Km
•
IFOV 170Km
•
NADIR RESOLUTION: 30 x 30 m (TM), 120 x 120 m (TM 104. 12.5 um)
•
DYNAMIC RANGE: 8 bits (ETM+)
•
SPECTRAL BANDS:
Band Number
Spectral
Range(microns)
Ground Resolution(m)
1
0.45 to 0.515
30
2
0.525 to 0.605
30
3
0.63 to 0.690
30
4
0.75 to 0.90
30
5
1.55 to 1.75
30
6
10.40 to 12.5
60
7
2.09 to 2.35
30
Pan
SPOT
372
0.52 to 0.90
15
•
SHORT NAME: SPOT_HRV
•
PLATFORM: SPOT
•
SENSOR: High Resolution Visible (HRV).
Sensor Platform Characteristics
•
SPOT 4 has two HRV sensors and an additional very wide angle
vegetaion instrument.
•
TYPE: Earth Resource Satellite System
•
DESCRIPTION: The SPOT HRV instruments consist of a linear
array of charge coupled device (CCD) detectors. Each detector
in the array scans a strip in the along track direction - this
reduces the need for mechanical scanning and a wide swath can
be imaged. A higher spatial resolution is also possible due to the
long effective dwell time.
The vegetation instrument in SPOT 4 uses the same spectral
bands as the HRV-IR instruments (B2, B3 and mid-IR) plus an
additional band known as B0 (0.43-0.47 µm) for oceanographic
applications
•
ORBIT: Sun synchronous, 98.7 degrees inclination 10:30 am
nominal equator crossing.
•
ALTITUDE: 832 km
•
REPEAT CYCLE: 26 days
•
NADIR X OVERLAP:
•
NADIR Y OVERLAP:
•
GROUND SWATH: 117 km (Richards) 185 km (Harrison)
•
NADIR RESOLUTION: 20 x 20 m (MSS), 10 x 10 m
(Panchromatic).
•
In SPOT 4 the Panchromatic band has been replaced by having
(MSS) band 2 also operate with a 10 x 10 m resolution.
•
DYNAMIC RANGE: 8 bits
•
SPECTRAL BANDS:
Band No.
Wavelength
(µ) microns
Bandwidth
(µ) microns
Central
Wavelength
(µ) microns
0.50-0.59
0.61-0.68
0.79-0.89
1.58-1.75
0.09
0.07
0.1
0.17
0.545
0.645
0.84
1.665
MSS
1
2
3
4 (SPOT 4)
Panchromatic (not in SPOT 4)
0.51-0.73
•
Sensor Platform Characteristics
0.22
0.62
ERMAPPER SENSORTYPE FILE:Two sensortype files:
373
•
cameras_and_sensors\ SPOT_XS.ers and
•
cameras_and_sensors\SPOT_PAN.ers.
cameras_and_sensors\SPOT_PAN.ers is shown below:
DatasetHeader Begin
Version = “1.0”
Name = “Spot 1 panchromatic”
DataSetType = ERStorage
DataType = Raster
RasterInfo Begin
CellType = Unsigned8BitInteger
NullCellValue = 0
CellInfo Begin
Xdimension = 10.0
Ydimension = 10.0
CellInfo End
NrOfBands= 1
BandId Begin
Value = “0.65”
Width = 0.16
Units = “um”
BandId End
RasterInfo End
DatasetHeader End
The cameras_and_sensors\SPOT_XS.ers is shown below
DatasetHeader Begin
Version = “1.0”
Name = “Spot 1 multispectral”
DataSetType = ERStorage
DataType= Raster
RasterInfo Begin
CellType = Unsigned8BitInteger
NullCellValue = 0
CellInfo Begin
Xdimension = 20.0
Ydimension = 20.0
CellInfo End
NrOfBands= 3
BandId Begin
Value = “0.545”
Width = 0.09
Units = “um”
BandId End
BandId Begin
Value = “0.645”
Width = 0.07
Units = “um”
BandId End
374
Sensor Platform Characteristics
BandId Begin
Value = “0.84”
Width = 0.1
Units = “um”
BandId End
RasterInfo End
DatasetHeader End
Sensor Platform Characteristics
375
376
Sensor Platform Characteristics
Data suppliers
Sample images include those obtained by Earth Resource Mapping
for development and testing purposes as well as for general
distribution with the ER Mapper software.
Earth Resource Mapping, the developers of ER Mapper, do not
provide the service of a bureau for remote sensed and geophysical
data. In order to promote both the flexibility of ER Mapper and the
images available, we approached the image processing community
and suppliers of remote sensed and geophysical data to provide a
sample of their data for testing purposes and/or as part of the
distributed product.
The sources of images shown below is by no means exhaustive, but
is complete in the sense that remote sensed and geophysical images
are commercially available from the organizations listed.
Australian Centre for
Remote Sensing (ACRES)
The Australian Centre for Remote Sensing provides Landsat TM and
MSS data products and has established a series of ACRES
distributors throughout Australia. Each distributor holds a complete
copy of the ACRES catalogue (image and data), a range of sample
products, price lists, order forms and information material.
For details of the nearest distributor in your state, contact:
Australian Centre for Remote Sensing
Dunlop Court, Fern Hill Park
BRUCE ACT 2617
PO Box 2 BELCONNEN ACT 2616
Telephone: (02) 6201 4201
Facsimile: (02) 6201 4366
http://www.ga.gov.au/acres/index.jsp
Australian Geological
Survey Organisation
(AGSO)
AGSO provided gridded aeromagnetic, aeroradiometric and gravity
grid values images. Located and gridded data for various areas of
Australia are available from the Australian Geological Survey
Organisation (AGSO)on magnetic tape. Orders for these images
should be addressed to:
Australian Geological Survey Organisation (AGSO)
GPO Box 378
CANBERRA ACT 2601
Telephone: (02) 6249 9111
Facsimile: (02) 6249 9999
http://www.agso.gov.au
Department of Mineral
Resources TAS
Department of Mineral Resources provides point data and vector
data with AMG coordinates of the Fingal Tier region. Open-file and
contract data is available from:
Department of Mineral Resources
Gordons Hill Road
PO Box 56
ROSNY PARK TAS 7018
Data suppliers
377
Telephone: (03) 6233 8333
Facsimile: (03) 6233 8338
http://www.mrt.tas.gov.au
Earth Observation
Satellite Company
Earth Observation Satellite Company (EOSAT) operates the U. S.
Landsat system of remote sensing satellites, and distributes data
through a network of international ground stations, representatives,
and field offices. Since 1972, Landsat satellites have acquired over
2.5 million multispectral images of the earth’s surface. For
information on EOSAT products and services, contact:
Space Imaging
12076 Grant St.
Thornton, CO 80241
Telephone: 1-303-254-2000
Facsimile: 1-303-254-2215
http://www.spaceimaging.com
Eurimage
Eurimage is a distributor of satellite imagery and related products
throughout the European community. They are a service oriented
company that concentrates on meeting the growing need for
environmental information. Eurimage provides products in both
digital and photographic formats, including raw data, standard
processed products, enhanced products, geocoded products, and
cartographic maps derived from satellite imagery. For more
information, contact:
Eurimage
Viale E. D’Onofrio, 212
00155 Rome, Italy
Telephone: +39-06-40 69 45 55
Facsimile: +39-06-40 69 42 31/32
http://www.eurimage.com
GeoImage Pty Ltd
GeoImage are official distributors of ACRES Thematic Mapper and
MSS digital and image products and offer advice on the best type of
products for individual applications. They can also supply copies of
digital data and slide sets of the Queensland Department of Resource
Industries open-file geophysical data. Image products and digital
data on any type of magnetic media can be purchased directly from:
GeoImage Pty Ltd
13/180 Moggill Rd,
Taringa, Brisbane QLD
P.O Box 789, Indooroopilly QLD 4068
Telephone: (07) 3871 0088
Facsimile: (07) 3871 0042
http://www.geoimage.com.au
378
Data suppliers
Intera Information
Technologies Corporation
Intera is a leader in providing spatial information solutions to
petroleum and other resource industries, and to governments.
Intera is a specialist in the aquisition and use of radar data for many
different applications. For more information on Intera products and
services, contact:
Intera
5th Floor
3609 South Wadsworth Blvd.
Denver, Colorado, USA 80235
Telephone: (303) 985-9900
Facsimile: (303) 985-4111
http://www.hartpub.com/bg/vd/7c.htm
Kevron Geophysics Pty
Ltd
Kevron Aerial Surveys provides high resolution airborne magnetic
and aeroradiometric geophysical data. Data and client surveys are
available from:
Kevron Geophysics Pty Ltd
10 Compass Road
Jandakot Airport
PERTH WA 6164
Telephone: (08) 9417 3188
Facsimile: (08) 9417 3558
http://www.kevron.com.au
National Geophysical
Data Center
NGDC is the archival center for the airborne geophysical and remote
sensing images collected in 1988 along the eastern side of the
Osgood Mountains, Humboldt County, Nevada USA, an area that
includes a string of disseminated gold deposits know as the Getchell
Trend. The digital data are available from:
National Geophysical Data Center
NOAA, NESDIS (E/GC1)
325 Broadway
Boulder, Colorado USA
Telephone: (303) 497 6826
Facsimile: (303) 497 6513
http://www.ngdc.noaa.gov
RADARSAT International,
Inc.
RADARSAT International (RSI) processes and distributes data from
the Landsat and SPOT satellites collected in Canada, and also
distributes SPOT data collected anywhere in the world for the
Canadian market. In addition, RSI is the sole source in North
America for data from the European ERS-1 satellite. RADARSAT will
also market and distribute data from Canada’s RADARSAT satellite
due to be launched in 1994. For more information on RSI data
products, contact:
13800 Commerce Parkway
MacDonald Dettwiler Building
Richmond, British Columbia
V6X 2W2 Canada
Data suppliers
379
Telephone: (604) 244-0400
Facsimile: (604) 244-0404
http://www.rsi.ca
Satellite Remote Sensing
Services
The Satellite Remote Sensing Services provides facilities for the
acquisition, processing and analysis of remotely sensed data from
earth resources satellites, weather satellites, airborne scanners and
other sensors. For further information contact:
Department of Land Administration
65 Brockway Road
Floreat WA 6014
PO Box 471
Wembley WA 6014
Telephone: (08) 9340 9330
Facsimile: (08) 9383 7142
http://www.rss.dola.wa.gov.au/
SPOT Imaging Services
Pty Ltd
SPOT Imaging Services provides SPOT panchromatic and
multispectral imaging products. Each SPOT scene represents a
ground area of 60 km x 60 km. The resolution is 10 m in the
panchromatic mode and 20 m in the multispectral mode. Scenes are
distributed either in the form of magnetic tapes or as photographic
products by SPOT Imaging Services and their distributor network.
SPOT Imaging Services also provides image maps and Digital Terrain
Models derived from SPOT stereo data.
Singapore
SPOT ASIA
73, Amoy Street,
Singapore 0106
Republic of Singapore
Telephone: (65) 227 55 82
Facsimile: (65) 227 62 31
Australia
Spot Imaging Services Pty Ltd
P O Box 197
ST LEONARDS NSW 2065
Telephone: (02) 9906 1733
Facsimile: (02) 9906 5109
http://www.spotimage.com.au
USA
SPOT Image Corporation
1897 Preston White Drive
RESTON, VA., 22091
USA
Telephone: (703) 620 2200
Facsimile: (703) 648 1813
Europe
380
Data suppliers
16 bis, avenue Edouard-Belin
31030 Toulouse cedex/France
Telephone: (33) 61 53 99 76
Facsimile: (33) 61 28 18 59
SSC Satellitbild
Swedish Space Corporation (SSC) Satellitbild markets and
distributes high quality satellite imagery products and related
services and support. Their products include satellite image maps,
sensor composite satellite image maps, precision corrected satellite
imagery, and DTMs. They also offer project and consultancy services
in areas such as natural resources mapping and forest management
planning. For more information, contact:
SSC Satellitbild
P.O. Box 816
S-981 28
KIRUNA, Sweden
Telephone: +46 (0)980 671 00
Facsimile: +46 (0)980 160 44
http://www.zacom.se
USGS
The EROS Data Center receives, processes, and distributes earthimage data acquired by satellite and aircraft and investigates new
uses for such data.
U. S. Geological Survey
EROS Data Center
Sioux Falls, SD 57 198
Telephone: (05) 594 6151
http://edcwww.cr.usgs.gov
USA state index maps and information about available aeromagnetic
and aeroradiometric maps and profiles can be obtained from the
Branch of Geophysics.
Branch of Geophysics
U. S. Geological Survey
Mail Stop 964
Box 25046, Federal Center
Denver, CO 80225
Telephone: (303) 236 1343
http://www.usgs.gov/network/
Data suppliers
381
382
Data suppliers
Index
Symbols
# symbol in configuration files 10
$$ALG Parameter
in Dynamic Links menu file 187
& in menu files 163
.bar toolbar files 161
.dcf digitizer configuration files 194
.dig digitizer session files 195
.dtp digitizer type file 191
.dtp digitizer type files 192
.dxf files, linking to 8
.erm menu files 161
.ers file (raster header file) 8
.erv file (vector header file) 8
.ker filter files 135
.ldd map composition files 167
|ask colourchooser 296
Numerics
24 bit RGB output of hardcopy engine 209
A
accelerator keys in menus 163
ACRES 377
add transform (type) 270
adding and displaying a Dynamic Link 62
adding Dynamic Links 60
adding the menu option for Dynamic Links 65,
186
Advanced Very High Resolution Radiometer
sensor characteristics 359
aeromagnetic data suppliers 377
aeroradiometric data suppliers 377
aeroradiometric geophysical data suppliers
379
AGSO 377
airborne geophysical data suppliers 379
airborne magnetic data suppliers 379
Airborne scanner Geoscan characteristics 360
algorithm .alg file format 105, 113
algorithm commands in scripts 263
Algorithm types in map composition .ldd files
171
AlgorithmImagePS in map composition .ldd
files 174
AllLightsOff
in .alg algorithm files 119
AllowedValues Block
in map composition .ldd files 171
Index
Altek digitizers 193
angles in parameter specifications 12
ARC/INFO
example Dynamic Link PostScript generation program 89
linking to 8
arguments
initialization program 68
PostScript generation program 70
arguments for Dynamic Links 68
Array
in .ker filter files 128
arrays in parameter specifications 11
ASCII format
for digitizer coordinates 196
aspect ratio in hardcopy 211
Atmospheric
in raster dataset header files 35
AttitudeKappa
in raster dataset header files 36
AttitudeOmega
in raster dataset header files 36
AttitudePhi
in raster dataset header files 36
Australian Centre for Remote Sensing 377
Australian data suppliers 377
Australian Geological Survey Organisation
377
Author
in .alg algorithm files 113
AverageHeight
in raster dataset header files 34
AVHRR sensor characteristics 359
B
BackGroundColor
in .alg algorithm files 114
BackgroundColour Block
in hardcopy .hc files 158
BackGroundColourSet
in .alg algorithm files 114
band_range specifying for command line importing 215
BandId Block
in raster dataset header files 29
BandID Blocks
in .frm formula files 132
Band-Interleaved-by Line data format 44,
213
BandNumber
in .frm formula files 132
BATCH
in menu and toolbar files 162
383
batch scripting
actions 257
algorithm commands 263
batch script library 282
cell type 287
color keywords 279
controls 290
dialog boxes 248
documentation 225
ER Mapper objects 253
example script 229
example wizard script 234
file name, extension and path keywords
279
filter commands 273
flow control 290
formula commands 272
getting started 226
image manipulation 254
input in scripts 247
language and commands, see scripting
language
layer commands 267
page setup commands 275
page size chooser 288
page view mode commands 276
preferences commands 277
print commands 280
run script from command line 228
see also wizards 239
status dialog 281
surface commands 265
transforms commands 270
using preferences to remember settings
251
variables 284
view mode commands 276
warning command 336
warning dialog 281
window commands 262
wizards 250
wizards page layout 236
BaudRate
in .dcf digitizer configuration files 194
Begin-End blocks 13
BIL (Band-Interleaved-by Line) data format
44, 213
blocks
file syntax 13
Bottom
in .alg algorithm files 120
BottomBorder
in .alg algorithm files 118
BottomRightCorner Block
384
in .alg algorithm files 116
Boundingbox in map composition .ldd files
174
box syntax in vector data files 55
button action command in batch scripting 294
ButtonDown
in .dtp digitizer type file 192
buttons
Color 62
Dataset chooser 61
Dynamic Link chooser 61
Dynamic Link layers 60
Edit 62
Open Annotation Editor 62
ButtonUp
in .dtp digitizer type file 192
ByteOrder
in raster dataset header files 23
in vector dataset header files 50
C
C
code 135
function arguments 147
function format 144
user defined function name 144
C function source code 143
C programming language in Dynamic Links 18
Calcomp digitizers 193
CalibrationDate
in raster dataset header files 31
CALLBACK
in menu and toolbar files 162
callback options available 163
CameraManufacturer
in raster dataset header files 30
CameraModel
in raster dataset header files 30
CanEdit
in .alg algorithm files 126
CANVASHEIGHT argument in PostScript generation programs 92
CANVASWIDTH argument in PostScript generation programs 92
cartographic maps suppliers 378
Cell type in batch scripting 287
cell_range specifying for command line importing 215
ChooseGcpsFromDigitizer
in raster dataset header files 34
ChooseGcpsFromImage
in raster dataset header files 34
chooser button for Dynamic Links 61
Index
chooser program for Dynamic Links 66
choosing for Dynamic Links 62
choosing the data source for a Dynamic Link
63, 187
chroma correction in hardcopy 210
CLibrarySwitches
in configuration file config.erm 104
color
and Dynamic Links 73
creating color lookup tables 151
hardcopy 211
in hardcopy or printing 211
color chooser button 62
color compression in hardcopy or printing 209
color lookup table files 155
Color types in map composition .ldd files 172
ColorMode
in .alg algorithm files 121
Columns
in .ker filter files 128
command line
running batch scripts 228
Comments
in .alg algorithm files 113
in .dig digitizer session files 195
in .dtp digitizer type file 191
in ER Mapper files 10
in hardcopy .hc files 159
compiling libermapper programs on PC 140
compression of images in hardcopy 210
ConfigFile
in .dig digitizer session files 195
container blocks in wizards 358
container right|left|justify 241
Continuous mode for digitizers 196
ControlPoints
in raster dataset header files 34
ConvertToGreyscale
in .alg algorithm files 114
convolution 135
convolutions, See filters 127
coordinate conversion utility programs 221
coordinates in pixels in Dynamic Link PostScript 101
CoordinateSpace Block
in .alg algorithm files 115
in vector dataset header files 51
CoordinateType
in .alg algorithm files 116
in raster dataset header files 24
in vector dataset header blocks 51
Correction Block
in raster dataset header files 35
385
D
data file
raster datasets 21
data formats 15
data source 62
choosing for Dynamic Links 63
defining in algorithms 105
data suppliers in Australia 377
data suppliers in Europe 378
database
adding links to the menu file 183
databases
links to 16
DataBits
in .dcf digitizer configuration files 195
DataFile
in raster dataset header files 23
in vector dataset header files 50
Dataset
in .alg algorithm files 122
Dataset Chooser
in Dynamic Links menu file 187
Dataset chooser button 61
DatasetHeader Block
in raster header files 21
in vector header files 49
datasets
importing 15
raster data files 44
vector data files 54
vector header files 47
DataSetType
in raster dataset header files 22
in vector dataset header files 49
DataType
in raster dataset header files 22
in vector dataset header files 50
dates in parameter specifications 12
Datum
in .alg algorithm files 115
in raster dataset header files 24
in vector dataset header blocks 51
datum
specifying for command line importing 219
DBMS
Dynamic Links to 20, 59
debugging Dynamic Links 73
DefaultHardcopy
in configuration file config.erm 104
DefaultHistStyle
in configuration file config.erm 104
DefaultHSILUT
in configuration file config.erm 103
DefaultRGBLUT
Index
in configuration file config.erm 103
DefaultRtShade
in configuration file config.erm 104
deleting files and directories in scripts 278,
308
Department of Mineral Resources TAS data
suppliers 377
Description
in .alg algorithm files 113, 122, 123
in .frm formula files 131
in .ker filter files 127
in .lut lookup table files 156
in Dynamic Links menu file 185
in map composition .ldd files 169
device DPI in PostScript 100
dialog boxes, creating with scripts 248
digitizer
configuration file .dcf format 194
coordinates 196
modes 196
session file .dig 195
support 196
digitizer type file .dtp 191
DigStringLength
in .dtp digitizer type file 191
dimensions in points in Dynamic Links 97
direct editing of external data using Dynamic
Links 59
disk2tape utility program 222
DisplayBBox
in .alg algorithm files 119
dithering in hardcopy or printing 209
DoOptimisation
in configuration file config.erm 104
DoStaticShade
in .alg algorithm files 122
DotsPerInchAcross
in hardcopy .hc files 157
DotsPerInchDown
in hardcopy .hc files 157
dpiX PostScript variable 95
dpiY PostScript variable 95
DrawMode
in .alg algorithm files 118
DTMs data suppliers 381
dump_cct utility program 222
dynamic compilation on PC 135
Dynamic Link Overlay Entries in .alg algorithm
files 125
Dynamic Link to ARC/INFO 89
Dynamic Links 16
adding 60
adding the menu option 65, 186
arguments 68
386
choosing a data source 62
choosing the data source 66, 187
creating 64
debugging 73
displaying the data 84
example 75, 80, 89
examples 20, 59
extracting the data 64
georeferenced overlays 60
initializing 63, 66
initializing the link 62
inside 62
introduction 59
layer buttons 60
link initialization program 67, 68
error reporting 69
example 69
menu options 65
multiple 59
output of data chooser program 66
output of link initialization program 68
page relative overlays 60
PostScript 64, 95, 97
generation program 70
error reporting 71
output 71
printing 72
procedure for displaying 62
Read/Write 59
supplied with ER Mapper 19
to DBMS 20
to vector files 20
using existing 62
dynamiclinks.erm Dynamic Link menu file 186
dynamiclinks.erm file format 65
E
Earth Observation Satellite Company data
suppliers 378
EarthCurvature
in raster dataset header files 35
ecw_compress image compression command
222
ecw_compress_gui image compression command 223
edit button 62
EDIT flag
in Dynamic Links menu file 186
EDIT parameter in Dynamic Link menu file 65
Edit program
in Dynamic Links menu file 186
editable links 59
editing filenames in scripts 278, 311
Index
EnforceAspectRatio
in configuration file config.erm 104
environment variables
getting a value in scripts 278, 326
setting in scripts 278, 355
EOSAT data suppliers 378
ER Mapper raster translator 15
erm_arc_layer Dynamic Link chooser program
89
erm_tapeutil utility program 221
ERMConfig Block
in configuration file config.erm 103
ermhe hardcopy engine 198
erminit_en0, example link initialization program 80
ermps_arc Dynamic Link PostScript generation program 91
ermps_example, PostScript generation program 76
ermps_table_circle, example Dynamic Link
PostScript generation program 84
EROS data suppliers 381
errors
in Dynamic Link initialization programs 69
in Dynamic Link PostScript generation programs 71
ERS-1 data suppliers 379
ervecmacro.erm file 101
Eurimage data suppliers 378
European data suppliers 378
example
algorithm file 105
batch script 229
complex dataset header file 39
dataset header file 38
Dynamic Link chooser program 89
Dynamic Link initialization program 69
Dynamic Link to ARC/INFO 89
Dynamic Links 59
file syntax 13
formula .frm file 131
Georeferenced dataset header file 39
hardcopy .hc file 157
hardcopy filter program 200
importing raster files 216
importing vector files 219
Landsat dataset header file 38
lookup table file 155
map composition .ldd files 178
map item .ldd file 169
PostScript 96
PostScript in Dynamic Links 99
Table of data shown as circles Dynamic
Link 78
387
user Dynamic Link 75
vector header files 53
wizard script 234, 240
Example User Dynamic Link menu option 75
exit from batch scripts 311
exiting in scripts 290
ExposureCenterX
in raster dataset header files 36
ExposureCenterY
in raster dataset header files 36
ExposureCenterZ
in raster dataset header files 36
Extents Block
in vector dataset header blocks 52, 53
external data formats, linking to 8
External Link Chooser
in Dynamic Links menu file 188
EyeXYZ
in .alg algorithm files 119
F
Far
in .alg algorithm files 120
FFTInfo Block
in raster dataset header files 37
Fiducial point block
in raster dataset header files 31
FiducialInfo Block
in raster dataset header files 30, 31
file exists 279
file extensions 7
file format
map composition .ldd files 167
menu files 161
raster files 7
toolbar files 161
vector files 7
File name, extension and path keywords 312
file syntax example 13
file_skip specifying for command line importing 216, 218
FileExtent
in .alg algorithm files 126
FileFormat
in vector dataset header blocks 52
filmwriter specification files 157
filter program
example 200
filter programs in printing or hardcopy 197,
199
FilterProgram
in hardcopy .hc files 158
FilterProgramName
Index
in .alg algorithm files 126
filters
C 129
convolution 135
defining in algorithms 105
file format 142
script commands 273
threshold filter 135
Fixed Parameter
in Dynamic Links menu file 187
fixed text syntax in vector data files 56
FlagPosition
in .dtp digitizer type file 192
FlyFar
in .alg algorithm files 120
FlyFOV
in .alg algorithm files 120
FlyNear
in .alg algorithm files 120
Font type in map composition .ldd files 172
Formula
in .alg algorithm files 123
in .frm formula files 131
formula
functions 143
script commands 272
Formula Sub-Blocks
in .alg algorithm files 123
FormulaArg Blocks
in .alg algorithm files 124
in .frm formula files 131
formulae
defining in algorithms 105
free space, finding out in scripts 278, 319
from72pt PostScript variable 97
fromdevpt PostScript variable 97
fromgeo utility program 221
G
Gamma Block
in hardcopy .hc files 158
gdt_conv utility program 221
Generate block
in map composition .ldd files 174
geocoded data suppliers 378
GeoImage Pty Ltd data suppliers 378
geolinking
in scripts 263, 354
geophysical data suppliers 378
georeferenced data 60
georeferenced layers 60
Geoscan MSS Mark 2 sensor characteristics
360
388
GIS
adding links to the menu file 183
Dynamic Links to 59
GivenOrthoInfo Block
in raster dataset header files 36
GMT (Greenwich Mean Time) in date specifications 12
goto commands in scripts 290
graphics format printing specification files 157
gravity data suppliers 377
Grid in map composition .ldd files 176
GTCO digitizers 193
H
hardcopy
aspect ratio 211
chroma correction 210
color 211
color compression 209
configuring the /etc/printcap file 211
creating a filter program 199
device independent output 197
device specific format 210
dithering 209
ermhe engine 198
image compression 210
output format 199
output program 210
output size 211
processing and filter programs 197
processing stages 197
strip printing 198
subsampling and supersampling 211
HardcopyInfo
in hardcopy .hc files 159
header file
for raster and vector data 7
for vector datasets 47, 48
HeaderOffset
in raster dataset header files 24
HeadMatrix
in .alg algorithm files 119
HeightI PostScript variable 95
HRV sensor characteristics 372
I
if ... then ... else commands in scripts 290
image compression in hardcopy 210
image file compression 222
images
importing 15
importas2482 example command line importing 219
Index
importascii example command line importing
216
importbil example command line importing
217
importcct example command line importing
217
importdisimp example command line importing 217
importdola example command line importing
217
importgeoimage example command line importing 219
importing
command line switches 214, 218
raster and vector files 15, 213
raster file examples 216
vector file examples 219
importusgs example command line importing
218
including files in scripts 291
InitialisationProgram
in .alg algorithm files 126
initialization
arguments to program 68
example program 80
Initialization program
in Dynamic Links menu file 186
Initialization program for Dynamic Links 65
initializing Dynamic Links 62, 63, 66, 67
INPUTVECTOR 148
integers in parameter specifications 11
Intera data suppliers 379
InterfaceType
in .ker filter files 129
invert inverting utility program 213, 219
IRS-IC sensor characteristics 364
K
Kernel Blocks
in .alg algorithm files 125
Kernel Sub-Blocks
in .alg algorithm files 123
Kevron Geophysics Pty Ltd data suppliers 379
keywords
in parameter specifications 12
L
labels in scripts 290
LANDSAT 4 sensor characteristics 367
LANDSAT 5 sensor characteristics 369
LANDSAT 7 sensor characteristics 372
Landsat data suppliers 378, 379
Landsat MSS data suppliers 378
389
LANDSAT MSS sensor characteristics 367
Landsat TM and Landsat MSS data suppliers
377
LANDSAT TM sensor characteristics 369
LastCharacter
in .dtp digitizer type file 191
LastUpdated
in .alg algorithm files 114
in raster dataset header files 23
in vector dataset header files 50
layers script commands 267
Left
in .alg algorithm files 120
LeftBorder
in .alg algorithm files 118
LegendRule block
in map composition .ldd files 169
LensSerialNr
in raster dataset header files 31
libermapper programs, compiling on a PC 140
Line mode for digitizers 196
line_range specifying for command line importing 215
Linepath in map composition .ldd files 174
LinePrinter
in configuration file config.erm 103
Link chooser
in Dynamic Links menu file 186, 187
link initialization program 68
links
choosing a data source 63, 187
to DBMS 20
to vector files 20
LinkType
in .alg algorithm files 126
list all image files 297
List types in map composition .ldd files 172
LoadMethod
in .lut lookup table files 156
lookup tables
creating 151
file format 155
Lookup value for pseudocolor display 155
LookupTable
in .alg algorithm files 121
loops in scripts 291
LUT
file entries 155
in .lut lookup table files 156
M
machine type, determining in scripts 287
makelut, color lookup table generation 151
Index
MANAGERELATIVEPATHS dynamic link chooser option 188
map composition .ldd files 167
map item object definition files 167
map_box and map_polygon object item definition files 167
map_box syntax in vector data files 57
map_polygon syntax in vector data files 57
MaterialAmbient
in .alg algorithm files 120
MaterialDiffuse
in .alg algorithm files 120
MaterialShininess
in .alg algorithm files 120
MaterialSpecular
in .alg algorithm files 120
MaximumDotsAcross
in hardcopy .hc files 158
MaximumDotsDown
in hardcopy .hc files 158
MaximumInputValue
in .alg algorithm files 124
MaximumOutputValue
in .alg algorithm files 125
menu .erm files 161
menu entries in Dynamic Links menu file 183
Menu option
in Dynamic Links menu file 185
menu options
adding for Dynamic Links 65
specifying keyboard selection keys 163
Menu/button option
in menu and toolbar files 161
MenuButtonDescription
in .alg algorithm files 125
mergeers merging utility program 213
MinimumInputValue
in .alg algorithm files 124
MinimumOutputValue
in .alg algorithm files 125
ModelMatrix
in .alg algorithm files 119
Monocolor PostScript 65, 73
Monocolour PostScript
effect on performance 101
MosaicType
in .alg algorithm files 114
MSS sensor characteristics 367
multispectral data suppliers 378, 380
N
Name
in .alg algorithm files 113, 120, 123
390
in .dcf digitizer configuration files 194
in .dig digitizer session files 195
in .frm formula files 131
in .ker filter files 127
in .lut lookup table files 156
in hardcopy .hc files 157
in map composition .ldd files 170
in raster dataset header files 23
National Geophysical Data Center data suppliers 379
navigation buttons container in wizards 238
Near
in .alg algorithm files 120
NGDC data suppliers 379
No Parameter
in Dynamic Links menu file 187
NOAA 359
NorthArrow in map composition .ldd files 176
NrEntries
in .lut lookup table files 156
Number types in map composition .ldd files
171
O
object syntax in vector files 55
objects in vector files 55
OkOnSubsampledData
in .ker filter files 128
open standards for file and data formats 7, 18
operators in scripting language 291
Option separators
in menu and toolbar files 163
Oracle, linking to 8
orthorectification 27
output in scripts 280
output of Dynamic Links data chooser program 66
output of Dynamic Links initialization program
68
output of Dynamic Links PostScript generation
program 71
output program for hardcopy 210
output size in hardcopy 211
OutputProgram
in hardcopy .hc files 158
oval syntax in vector data files 55
P
page relative data 60
page relative layers 60
page setup
script commands 275
page size chooser in batch scripting 288
Index
page view mode 276
page view mode, determining in scripts 286
PageConstraint
in .alg algorithm files 117
PageHeight
in .alg algorithm files 118
PageSize Block
in .alg algorithm files 116
PageViewMode
in .alg algorithm files 113
PageWidth
in .alg algorithm files 117
panchromatic data suppliers 380
Paper Types
in hardcopy .hc files 159
Parameter types in map composition .ldd files
171
parameters
in Dynamic Links menu file 185
in ER Mapper files 10
syntax 10
Parity
in .dcf digitizer configuration files 194
performance and accuracy in PostScript Dynamic Links 100
petroleum data suppliers 379
photocopier specification files 157
PlatformType
in raster dataset header files 30
plotter specification files 157
Point mode for digitizers 196
point syntax in vector datasets 55
polygon syntax in vector data files 56
PolyLens
in raster dataset header files 35
polyline syntax in vector data files 56
Port
in .dcf digitizer configuration files 194
PostScript
adding links to the menu file 183
commands
moveto 95
converting data in Dynamic Links 62
device DPI 100
dimensions in pixels 95
example code 96
file size effects on performance 100
functions in ER Mapper 98
in Dynamic Links 18, 64, 95
interpretation in Dynamic Links 95
linking to 8, 59
Monocolor or Truecolor 65, 73
effect on performance 101
performance and accuracy 100
391
using existing 101
variable canvas size 95
variables 97
dpiX 95
dpiY 95
from72pt 97
fromdevpt 97
HeightI 95
WidthI 95
variables defined in ER Mapper 95
PostScript conversion program 70
PostScript generation program 64
PostScript generation program call
in Dynamic Links menu file 185
PostScript type
in Dynamic Links menu file 185
PostScriptPrinter
in configuration file config.erm 103
preferences
script commands 277
printer specification files 157
printing
output program 210
output size 211
processing and filter programs 197
processing stages 197
see also hardcopy 197
printing Dynamic Links 72
printing in scripts 280
printing output format 199
ProcessFirst in map composition .ldd files 174
Program call
in menu and toolbar files 162
Projection
in .alg algorithm files 116
in raster dataset header files 24
in vector dataset header blocks 51
projection
specifying for command line importing 219
pseudocolor
creating color lookup tables 151
lookup table files 155
PSExecInclude Block
in map composition .ldd files 177
PSLibInclude Block
in map composition .ldd files 177
R
radar data suppliers 379
RADARSAT International, Inc. data suppliers
379
RadialLens
in raster dataset header files 35
Index
raster datasets
data files 44
header file 21
header files 21
importing 15
raster file format 7
integrating data 15
raster image
importing 213
raster images
header files 21
import switches 214
importing 15
importing examples 216
Read/Write Dynamic Links 59
real numbers in parameter specifications 11
RegionInfo Block
in raster dataset header files 31
RegionName
in raster dataset header files 32
RegistrationCellX
in raster dataset header files 27
RegistrationCellY
in raster dataset header files 27
RegistrationCoordinate block
in raster dataset header files 28
remote sensing data suppliers 379
RGBcolour Block
in .alg algorithm files 126
Right
in .alg algorithm files 120
RightBorder
in .alg algorithm files 118
rmoveto
PostScript command 95
Rotation
in .alg algorithm files 116
in raster dataset header files 25, 34
in vector dataset header blocks 52
rotation
specifying for command line importing 219
Rows
in .ker filter files 128
RSAC data suppliers 380
run length limited image compression in hardcopy 210
S
Satellite Remote Sensing Services data suppliers 380
SCALE
in raster dataset header files 36
Scale
392
in .alg algorithm files 118
ScaleBar in map composition .ldd files 175
Scalefactor
in .ker filter files 128
ScreenAxesRotn
in .alg algorithm files 119
scripting language
absolute|relative path 291
add (new) layer 267, 292
add (new) transform (to layer) 292
add filter 273
add filter (to layer) 292
add formula 272
add formula (to layer) 292
add height layer 244
add layer 267
add layer (to surface) 293
add surface (to algorithm) 265, 293
add transform (to layer) 270, 293
add transform point 270, 293
add transform to layer input 270, 293
algorithm2 = algorithm1 263, 294
ask 248
ask action 235, 241, 250, 294
ask bandchooser 249, 295
ask bandmenu 242, 249, 296
ask begin 231
ask colorchooser 249, 296
ask datum 249, 296
ask directory 249, 296
ask end 231
ask file 231, 249, 297
ask gridlayermenu 250, 297
ask hardcopy 250, 298
ask link 250, 298
ask listmenu 250, 299
ask listmenu_exclusive 241, 249, 300
ask lutmenu 250, 301
ask projection 301
ask text|number 250, 301
ask yes/no 238, 250, 301
build absolute filespec 277, 302
build file path 277, 302
build relative filespec 277, 302
color keywords 302
color_blue (keyword) 279, 302
color_green (keyword) 279, 302
color_red (keyword) 279, 302
concatenation 283
container above|below|left|right
241,
251, 303
container begin|end 235, 241, 251, 303
container items 241, 251, 304
container labels 251, 304
Index
container right|left justify 251
container right|left|justify 303
container width|height 241, 251, 304
convert file separator 304
convert to english|native 278
copy algorithm 263, 305
copy algorithm from window 235, 262,
305
copy algorithm to window 232, 245, 262,
305
copy filter 273, 305
copy formula 272, 305
copy layer 267, 306
copy surface 265, 306
copy transform 270, 306
copy window 255, 262, 306
current algorithm 254, 263, 306
current filter 254, 273, 307
current formula 254, 272, 307
current input 254
current layer 254, 267, 307
current surface 254, 266, 307
current transform 254, 270, 307
current window 254, 262, 308
delete algorithm 263, 308
delete directory|file 278, 308
delete filter 273, 308
delete formula 272, 308
delete layer 267, 309
delete status (dialog) 282, 309
delete surface 266, 309
delete transform 270, 309
delete window 262, 309
dialog box
title 231, 248
dirname (keyword) 279, 312
duplicate filter 273, 310
duplicate formula 272, 310
duplicate layer 267, 310
duplicate surface 266, 310
duplicate transform 270, 310
edit file 311
edit text file 278
error codes 291
execute system command 279
exists 311
exit 290, 311
exit batch process 278
file exists 279
fileext (keyword) 279, 312
filename (keyword) 279, 312
filter2 = filter1 312
filterl2 = filter1 273
first|last|nex|previous surface 314
393
first|last|next|previous algorithm 263,
312
first|last|next|previous filter 273, 313
first|last|next|previous formula 272, 313
first|last|next|previous layer 267, 313
first|last|next|previous surface 266
first|last|next|previous transform 270,
314
first|last|next|previous window 262, 314
fit page to hardcopy 275, 314
format number of digits after decimal
point 279
format value precision 315
get (algorithm) page view mode 276, 324
get (algorithm) view mode 277, 326
get (ER Mapper) version 326
get (page) contents topleft|bottomright
275, 315
get algorithm coordsys 264, 315
get algorithm datum|projection 264, 315
get algorithm description 263, 315
get algorithm layer count 264, 316
get algorithm lut 264
get algorithm lut (color table) 316
get algorithm mode 264, 316
get algorithm mosaic type 264, 316
get algorithm topleft|bottomright (extents) 264, 316
get algorithm units|rotation 264, 317
get english file separator 278, 317
get environment variable 278
get ER Mapper version number 279
get file size 278, 317
get filter description 273, 317
get filter matrix 273
get filter params 273, 317
get filter postsampled (flag) 273, 318
get filter rows|cols 273, 318
get filter scale|threshold (value) 274, 318
get filter type 274, 318
get filter userfile (filename) 274, 318
get filter userfunc 274, 318
get free space (on disk) 278, 319
get layer azimuth|elevation 268, 319
get layer band count 268, 319
get layer band description 268, 319
get layer cell size 268, 319
get layer cell type 268, 320
get layer color 267, 320
get layer coordinates 268, 320
get layer dataset (filename) 235, 268,
320
get layer description 268, 320
get layer edit|init program (name) 268,
Index
321
get layer editable (flag) 268, 321
get layer formula 268, 321
get layer input count 268
get layer input filter count 268, 321
get layer input transform count 268
get layer link extension 268, 321
get layer output filter count 268
get layer output transform count 268, 322
get layer shading 268, 322
get layer type 268, 322
get layer visibility 322
get layer|$lay input count 322
get native path|file separator 278, 323
get page constraints 275, 323
get page scale 275, 323
get page size 275, 323
get page top|bottom|left|right border
275, 324
get page topleft|bottomright (extents)
275, 323
get page width|height 275, 324
get preference 277, 324
get preference (color) 277, 325
get surface description 266, 325
get surface layer count 266, 325
get transform (limits) 325
get transform input|output min|max 271
get transform type 271
getenv (environment variable) 326
go algorithm 264, 326
go background window 262, 327
go window 262, 327
goto 290
if ... then ... else 232, 290
include "filename" 291
keywords 288
labels 290
layer active 268, 327
layer2 = layer1 267, 327
list contents of directory 278
listdir 278, 328
load algorithm 232, 264, 328
load filter (filename) 274, 328
load formula (filename) 272, 329
load layer formula (filename) 269, 329
looping 291
mathematical functions
abs(x) 284
asin(x), acos(x), atan(x) 283
ceil(x) 284
floor(x) 284
log(x), exp(x) 283
min(x,y), max(x,y) 284
394
pow(x,y) 283
sin(x), cos(x), tan(x) 283
sqrt(x) 284
move layer up|down|top|bottom 269, 329
move surface up|down|top|bottom 266,
330
new algorithm 264, 330
new filter 274, 330
new formula 272, 330
new layer 269, 331
new surface 266, 331
new transform 271, 331
new window 231, 262, 331
next layer 269
next layer (type) 332
open status (dialog) 282, 332
open window 262, 332
operators 283
!= > >= 283
# 283
() 283
= * / + - % 283
~ 283
previous zoom 263, 358
print 280, 333
println 281, 333
save algorithm 264, 334
save algorithm as dataset 264, 334
save algorithm as virtual dataset 264, 335
save filter (filename) 274, 335
save formula (filename) 272, 335
save layer formula (filename) 269, 335
say 231, 241
say status 282, 336
say warning 244, 281, 282, 336
select algorithm 264, 336
select filter 274, 336
select formula 272, 337
select layer 269
select surface 266, 337
select transform 271, 337
select window 231, 263, 337
set (formula) input to band 337
set (page) contents bottomright from
topleft 275, 338
set (page) contents extents to algorithm
extents 276, 338
set (page) contents topleft|bottomright
275, 338
set algorithm background (color) 264, 339
set algorithm coordsys 264, 340
set algorithm coordsys changeable to
(flag) 338
set algorithm datum|projection 264, 340
Index
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
set
395
algorithm description 264, 340
algorithm lut (color table) 264, 341
algorithm mode 265, 341
algorithm mosaic type 265, 341
algorithm supersample type 265, 341
algorithm topleft|bottomright (extents) 265, 342
algorithm units|rotation 265, 342
environment variable 278
filter description 274, 342
filter matrix (element) 274, 343
filter params 274, 343
filter postsampled (flag) 274, 343
filter rows|cols 274, 343
filter scale|threshold 274, 344
filter type 274, 344
filter userfile (filename) 274, 344
filter userfunc (funcname) 274, 344
formula 272, 345
input to band 272
layer azimuth|elevation 269, 345
layer color 269, 345
layer dataset (filename) 244, 269,
346
layer description 244, 269, 346
layer edit|init program (name) 269,
346
layer editable (flag) 269, 346
layer formula 269, 347
layer input 245
layer input to band 269, 347
layer link extension 269, 347
layer link type to monocolour|truecolour 269, 347
layer shading on|off 269, 348
layer type 269, 348
output to filename|window 281, 333
page autovary_value 275, 339
page center horizontal|vertical 275,
348
page constraints 275, 348
page extents from contents 276, 348
page scale 276, 349
page size 276, 349
page top|bottom|left|right border
276, 350
page topleft|bottomright (extents)
276, 350
page view mode 276, 350
page width|height 276, 350
pointer mode 263, 351
preference 277, 351
preference (color) 277, 351
surface description 266, 352
surface lut (color table) 266, 352
surface mode 266
surface mode (color) 352
surface name 266, 352
surface zscale|zoffset|transparency
266, 353
set transform clip 271, 353
set transform input|output min|max (limits) 271, 353
set transform limits (actual or percentage)
271, 353
set transform output limits to input limits
271
set transform to gaussian equalize 271,
354
set transform to histogram equalize 271,
354
set transform type 271, 354
set view mode 245, 277, 354
set window geolink mode 232, 263, 354
setenv (environment variable) 355
show image 239, 241, 251
show image (in container) 355
split string into array 279, 356
surface active 266, 356
system command 356
system command status dialog 279
transform2 = transform1 270, 357
turn layer on|off 269, 357
turn surface on|off 266, 357
variables 284
arrays 287
color 286
coordsys 285
filtertype 286
layertype 285
machinetype 287
mode 285
mosaictype 285
number 284
page size options 288
pageviewmode 286
references 286
string 284
supersampletype 286
transformtype 286
viewmode 286
yesno 285
window2 = window1 262, 357
wizard begin|end 241
wizard close 251, 357
wizardpage begin|end 251, 358
zoom in|out 263, 358
zoom to 263, 358
set
set
set
set
set
Index
SenseDate
in raster dataset header files 23
in vector dataset header files 50
sensor_type specifying for command line importing 216
SensorInfo Block
in raster dataset header files 29
SensorName
in raster dataset header files 23
SensorType
in raster dataset header files 30
set 341, 342
Sharp JX730 example hardcopy filter program
200
SourceDataset
in raster dataset header files 23
splitting strings in scripts 279, 356
SPOT data suppliers 379, 380
SPOT Imaging Services Pty Ltd data suppliers
380
SPOT sensor characteristics 372
spreadsheets
links to 16, 59
SSC Satellitbild data suppliers 381
Stats Block
in raster dataset header files 32
status dialog 281
StatusPosition
in .dtp digitizer type file 192
StopBits
in .dcf digitizer configuration files 194
Stream Blocks
in .alg algorithm files 121
StreamInput
in .frm formula files 131
StreamInput Sub-Blocks
in .alg algorithm files 123
StreamInputID
in .alg algorithm files 123
String types in map composition .ldd files 171
strings, splitting in scripts 279, 356
sub-blocks
file syntax 13
submenus
in the Dynamic Links menu 185
Submenus in menu files 162
SubRegion
in raster dataset header files 32
subsampling and supersampling in hardcopy
production 211
SunAngle
in .alg algorithm files 122
SunAzimuth
in .alg algorithm files 122
396
SuperSampling
in .alg algorithm files 114
Surface Blocks
in .alg algorithm files 120
surface script commands 265
system command, executing in scripts 279
T
Table of data shown as circles, example Dynamic Link 78
tabular data
dynamic links to 59
tape utility programs 221
tape_struct utility program 222
tape2disk utility program 222
testing Dynamic Links and import and export
utilities 18
text strings in parameter specifications 11
ThreeDInfo Block
in.alg algorithm files 118
threshold filter 135
scripting language
match transform 271, 329
togeo utility program 221
Tool tips text
in menu and toolbar files 162
toolbar .bar files 161
Top
in .alg algorithm files 120
TopBorder
in .alg algorithm files 118
TopLeftCorner Block
in .alg algorithm files 116
Transform Point Coordinate Block
in .alg algorithm files 125
Transform Sub-Blocks
in .alg algorithm files 124
transforms
defining in algorithms 105
script commands 270
Transparency
in .alg algorithm files 121
Truecolor PostScript 65, 73
effect on performance 101
TurnRate
in .alg algorithm files 119
Type
in .alg algorithm files 122, 124
in .ker filter files 128
in map composition .ldd files 170
in raster dataset header files 31
in vector dataset header blocks 52
TypeFile
Index
in .dig digitizer session files 195
U
Units
in .alg algorithm files 116
in .frm formula files 132
in configuration file config.erm 103
in raster dataset header files 25, 29
in vector dataset header blocks 52
UseAverageHeight
in raster dataset header files 34
user code
C library switches 147
filter file format 142
filter object file 143
linking 147
on PC 135
UserCodeFileName
in .ker filter files 129
UserFunctionName
in .ker filter files 129
UserParameter Block
in map composition .ldd files 170
USERSTATS 148
USGS data suppliers 381
V
Value
in .frm formula files 132
in raster dataset header files 29
variable aspect ratio in PostScript Dynamic
Links 97
variable text syntax in vector data files 56
variables in scripting language 284
vector datasets
data file 47, 54
header file examples 53
header files 47, 48
importing 16, 213
vector file format 7
data integration 16
vector files
Dynamic Links to 20
vector header files
examples 53
vector images
command line import switches 218
importing 16, 213
vector objects
in datasets 55
syntax 55
VectorInfo Block
in vector dataset header blocks 52
397
Velocity
in .alg algorithm files 119
verify existence of specified file 279, 311
Version
in .alg algorithm files 113
in .lut lookup table files 155
in configuration file config.erm 103
in raster dataset header files 22
in vector dataset header files 49
view mode
script commands 276
view mode, determining in scripts 286
ViewMatrix
in .alg algorithm files 119
ViewMode
in .alg algorithm files 113
W
warning command in batch scripting 336
warning dialog 281
WarpControl Block
in .dig digitizer session files 196
in raster dataset header files 32
WarpType
in raster dataset header files 34
Width
in .frm formula files 132
in raster dataset header files 29
WidthI PostScript variable 95
WindowAspectRatio
in .alg algorithm files 119
wizards
ask and show commands 238
container block 237, 358
container navigation buttons 238
example script 234, 240
general guidelines for creating 239
information container 236
navigation container 236
navigation container buttons 238
page layout 236
show image command 239
user input container 236
WizardPage Block 237
X
Xdimension
in raster dataset header files 28
XPosition
in .dtp digitizer type file 192
Y
Ydimension
Index
in raster dataset header files 28
YES/NO types in map composition .ldd files
171
YPosition
in .dtp digitizer type file 192
Z
ZOffset
in .alg algorithm files 121
zoom 358
zooming in scripts 358
ZScale
in .alg algorithm files 121
ZScale in map composition .ldd files 176
398
Index
399
Index
400
Index

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project