ARRI Projection HDTV User's Manual

ALICE
COLOR MANAGEMENT
Instruction Manual
As of: April 2003
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Contents
Contents
Safety Instructions ......................................................... 3
3
The File Menu .................................................. 18
1
ALICE
ARRILASER Interactive Configuration Editor........... 5
4
Configuration................................................... 20
2
Operation.......................................................... 7
4.1
2.1
Viewer area....................................................... 7
Timeline............................................................. 8
Projectable Area ................................................ 9
Pixel Info............................................................ 9
Display Settings.................................................. 9
Naming Conventions in ALICE .......................... 20
Cinemascope geometries.................................. 20
Inter Positive fullap geometries ........................... 21
Loader LUTs for Color Management ................... 21
4.2
Input Format File Specification ........................... 22
Location of input format file ............................... 22
Syntax of input format file.................................. 22
4.3
Fine-tuning ALICE ............................................. 24
Memory Footprint............................................. 24
Multi Threading................................................ 24
4.4
4.4.1
4.4.2
4.4.3
4.4.4
Accessing DVS Disk Recorders .......................... 25
Browsing Disc Recorders................................... 25
Network Timeouts............................................. 26
Partition Change Policy..................................... 26
Command Line Interface Syntax......................... 27
2.2
2
Configuration Area .......................................... 11
Input Format..................................................... 11
Output Format.................................................. 12
Calibration ...................................................... 12
Crop Area....................................................... 13
Crop box handling with the aspect locked:......... 13
Crop box handling with the aspect unlocked: ..... 14
Right mouse button ........................................... 15
Deinterlace ...................................................... 16
Sharpen .......................................................... 16
CMS ............................................................... 17
5
Color Management for Video Look .................... 28
5.1
5.1.1
5.1.2
5.1.3
Operation from ALICE ...................................... 28
Configuration of CMS node in ALICE................. 28
Soft clip Parameter ........................................... 29
Display settings ................................................ 30
Caution:
This manual is an addendum to the existing
ARRILASER instruction manual.
Please make sure to read the ARRILASER
manual prior to continuing with this manual!
Contents
Safety Instructions
5.2 Configuration................................................... 32
5.2.1 Monitor Setup .................................................. 32
Calibration of the HD class A reference monitor.. 32
5.2.2 Film Setup........................................................ 32
5.2.3 Color Management Node................................. 33
The CMS node syntax ...................................... 33
Node type identifier and node arguments .......... 34
5.2.4 Soft clip Configuration File ................................ 35
Location of soft clip configuration file.................. 35
Syntax of soft clip configuration file.................... 35
Soft clip parameters demystified ........................ 37
5.3
Provided profiles .............................................. 37
3
4
Introduction 1
The ALICE offers the fastest, easiest and safest way to
generate a new image processing configuration file and
gives visual control over the whole image process from
the raw input sequence to the final images positioned
on the film. General input parameters like start/end
frame, calibration and loader-LUT can also be specified
and will be transferred to the GUI input window when
quitting and saving the ALICE window. Furthermore
additional information is provided about the input
images such as image type, pixel size and bit depth.
Analyzing and controlling tools further simplify the
configuration process.
The purpose of ALICE is
• to judge the quality of the input images
• to select the frame range visually
• to build a job and select appropriate job settings
with visual control of the final rendered images
positioned on the film.
• By choosing an ICC profile for the workstation monitor,
the effect on the actual output on film can be previewed.
This is especially helpful in transferring colors that lie
outside of the normally reproduced color space of the
choosen film. All results can be accurately previewed.
Introduction 1
1 ALICE
ARRILASER Interactive Configuration Editor
ALICE uses the same image processing as the image processing used during recording. Therefore, the results of image
processing operations previewed in ALICE are completely
identical to those being recorded later. Zooming in and out is
always done by replicating or omitting pixels to exclude
all possibility of inaccuracy of the displayed image.
5
Operation 2
viewer area •
• projectable area
• pixel info
film view •
processed view •
• display settings
original view •
timeline •
• home button
• configuration area
6
2.1 Viewer area
To start ALICE click the ALICE Button beneath the image
processing configuration list in the input tab of ALGUI.
Any preselected image processing file will be applied in
ALICE, as long as it is compatible with ALICE’s configuration.
If not, or if no file is selected at all, ALICE will be opened
with default settings. Geometry, loader LUT and calibration
can be preselected before opening the ALICE window or
inside the ALICE window. If a chosen setting is not compatible
with the ALICE configuration default values will come up.
The viewer area includes the viewer window, timeline,
projectable area, pixel info and display settings. It offers a
visual control of the raw input sequence and is used to
create interactively the configuration parameters. A preview
shows the actual position of the final images on the film.
The ALICE window is separated into the viewer area
and the configuration area  photo.
• The ‘original’ view shows the original raw input
images.
Operation 2.1
2 Operation
• The ‘processed’ view accurately displays the effects
of the chosen filter and geometry settings (output
format, crop area, deinterlace, sharpen and CMS, if
activated).
• The ‘film’ view shows the processed images
positioned on the film for final control.
• The ‘timeline’ is simply a display of a frame range.
By default it is the length of the clip or sequence. It
does not limit or control the actual start/end
parameters saved in the jobscript.
7
Operation 2.1
Timeline
• To change the displayed frame range, enter the start/end
frame in the corresponding text field at the beginning
and end of the timeline  photo.
The ‘cur‘ field shows  photo the actual displayed
frame number. Typing a particular number in that
field will show this frame on the display.
The ´inc´ value  photo indicates the step width
for moving through the timeline using the arrow keys
on your keyboard. To skip frames, change the ‘inc’value numerically or by choosing the predefined
values in the drop down list.
• To reset the displayed frame range click on the home
button at the right end of the timeline. This will
refresh the images and reset the frame range.
8
• Additional keyboard shortcuts can be used.
Arrow left/right:
retreat/advance a step based on the frame
increment setting.
Page up/down:
retreat/advance by approx. a tenth of the timeline
range.
CTRL + arrow up/down:
double/half the increment value.
Display Settings
• By choosing an output format in the ‘projectable area‘
 photo, internally the corresponding ‘projector
mask’ is selected. The ‘projector mask‘, the ‘save title
area’ or both together can be activated. Additionally
the reserved region for the soundtrack and the frame
line can be displayed.
• Choose a zoom factor from the drop down list in the
‘display settings‘ area  photo to zoom in/out
(25% - 200%) or use the right mouse button or
keyboard shortcuts.
Right mouse button:
zoom in/out, fit, 100% (the mouse pointer must be
positioned in the viewer window!)
Keyboard shortcuts:
ctrl –/+ (numerical keypad), ctrl F (Fit), ctrl 0 (100%)
Note:
The areas are only seen in the film view and
have no effect on the processed images!
Pixel Info
• With the mouse pointer you can pinpoint the RGB
code values (CV). The x/y position is shown in the
upper left corner of the ‘pixel info‘  photo section.
Note:
In the ‘original’ view the original CVs from the
input images (8, 10, 12 or 16 bit) are displayed.
In the ‘processed’ view 16 bit RGB values are
shown, because internally all image processing
is done in 16 bit. The ‘film’ view shows the 10 bit
cineon CV as they are sent to the recorder.
Those values will change by changing the
loader LUT.
Operation 2.1
Projectable Area
Beneath the zoom factor drop down list the information
about the position of the upper left image corner (X,Y)
and the size (width, height) of the displayed image
part is shown  photo
.
While the image is usually displayed as a linear
image (exception: Cineon files), the ´view cineon´
button will display the image in cineon logarithmic
space, as they will be transferred to the recorder. In
that mode the influence of changing the loader LUTs
can be seen. The ´view cineon´ button is only
activated in the film view.
To judge the influence of the Color Management, use
the ‘proof‘ and the ´gamut´ button (see chapter 5).
9
Operation 2.2.
input format •
ouput format •
calibration •
• crop area
• CMS
• Sharpen
• Deinterlace
10
This chapter explains all available ALICE nodes and their
parameters in a systematic way according to the standard
GUI configuration. It is mainly intended as a reference.
In this window a configuration file for the image
processing can be build.
Note:
This configuration file works only together with
the chosen geometry.
See chapter 5.5, Image Processing of the ARRILASER Manual,
for a detailed description of the image processing function.
Input Format
• In the ‘input format‘ section  photo the size, bit
depth and pixel aspect ratio of the selected sequence
are displayed.
By default images of the size 1920x1080 are automatically recognized as HDTV 1080 (pixel aspect 1.0),
of 1280x720 as HDTV 1280 (pixel aspect 1.0),
of 720x486 as NTSC (pixel aspect 0.9385), and
images of the size 720x576 are recognized as either
PAL (pixel aspect 1.067) or PAL Plus (pixel aspect 1.416).
Operation 2.2.
2.2 Configuration Area
The right choice for PAL or PAL Plus must be
selected by the user
All other formats are taken as generic and a pixel
aspect of 1 is assumed. For modifying this default
selection please refer to chapter 4.
Start and end frame for the selected sequences are
taken from the ALGUI window.
• To change the recordable frame range, enter the start/
end frame in the corresponding text fields  photo.
11
Operation 2.2.
Output Format
Calibration
• The determination of the ‘output format’  photo is
a two-stage selection procedure:
• Select the actual ‘calibration‘  photo
and ‘loader LUT‘  photo for the used film stock
and lab and the format conversion look-up-table (LUT).
First the desired projection aspect ratio must be choosen
(i.e.: 1:2,35 CS means squeezed for projection with
cinemascope lenses).
All available geometries for this aspect ratio will appear
in the second drop down list. The pixel resolution
and the pitch size provides additional information
about the chosen output geometry.
A crop box with the appropriate aspect ratio will
appear on the display. Geometries which are not
available in the list can be generated in the ALGUI
geometry setup as described in chapter 5.2.2.2 of
the ARRILASER manual. Restarting the ALICE software
will place those new geometries in the list.
Note:
12
Changing the ‘output format’ will reset the
crop area to the maximum appropriate
settings to fit into the new ‘output format’.
The LUT converts the given files into the Cineon format.
Choose 10log, if the files are already in the Cineon
format. Those settings are taken from the ALGUI
input window; changes will be returned to the
ALGUI input window.
• ‘Intermed Positive’  photo:
Adds the necessary changes to the image processing
config file for intermed positive recording.
Necessary adjustments like flip the image, paste on
black background and invert the loader LUT (interposlut)
are automatically done. Results can be seen in the
film view. No other adjustments need to be done for
intermediate positive recording.
• With the crop node a ‘crop area‘  photo can be
specified by the x/y-size and the origin of the crop box in
relation to the original image.
By selecting a projection aspect ratio (e.g. 1.66) in the
‘output format’ node the maximum appropriate ‘crop area’
settings are adjusted automatically and, if necessary,
the image is auto scaled to fit into the chosen ‘output
format’.
Operation 2.2.
Crop Area
By default the x-size of the crop box is set to
maximum input image width and the image height is
selected according to the aspect ratio.
Crop box handling with the aspect locked:
CTRL + drag the center -> move the crop box.
ALT + drag the border -> vary the size fixed to its center.
Drag a corner
-> vary the size fixed
to the opposite corner.
Drag a side
-> vary the size fixed
to the opposite side.
13
Operation 2.2.
Crop box handling with the aspect unlocked:
If the image should not be cropped in order to get the
selected output format the ´lock aspect´ button  photo
can be switched off. This mode allows to only downsize
the aspect ratio starting from the chosen ratio in the
‘output format’ node. The result is a horizontallycentered image with a letterbox on both sides. Check in
the film view for the look. The projectable image height
remains constant according to the chosen projection
aspect ratio.
To enlarge the aspect ratio (e.g. 1.66 to 1.85) means to
decrease the projectable image height. To do so, change
the projection aspect ratio in the output node!
14
Drag a side
-> vary the size fixed
to the opposite side.
ALT + drag a side
-> vary the size and aspect
fixed to the center.
To reset the crop box to its default, to maximize or center
the crop box use the right mouse button, when the mouse
is located in the image area.
Operation 2.2.
Right mouse button:
15
Operation 2.2.
Deinterlace
The ‘deinterlace‘  photo node enables the merging
of two fields of video originated frames. There are no
arguments required.
• For quick comparison between ‘deinterlace’ on/off
toggle key D in the processed view mode. Pushing
down the key will disable the effect on the image and
the color of the icon will change to black & white. For
‘effect on’ release the key.
Sharpen
The ‘sharpen‘ node  photo applies a sharpening process
on the image. The details of the sharpening process are
determined either by choosing a predefined kernel file and
following the description of the convolution node (see
chapter 5.5.2.4 of the ARRILASER manual), or by choosing
variable and using the unsharp masking as described in
chapter 4 of the Release Notes CLIF 3.5/ALGUI 3.44. In
this case a filter size and strength must be choosen. Filter
strength is set in percentage and can be varied from 0 to
200. To judge the sharpening effect set the display settings
to 100%. For quick comparison between sharpen on/off
toggle key S in the processed view mode.
16
The Color Management system (‘CMS‘  photo) node
is used to apply high quality profiles for standard devices
such as Sony HD Monitor and Kodak Vision print stock
projected by a xenon lamp in order to bring the colors of
the film output close to what can be seen on the monitor.
• In the ‘CMS‘ node a monitor profile (M) and a print
film profile (P) is selected.
Operation 2.2.
CMS
For images with high saturated colors the soft clip can
be adjusted by choosing one of the prepared soft clip
settings from the list. See chapter 5 Color Management
for Video look for more detailed information on the
Color Management. To judge the CMS settings switch
the proof button on. For quick comparison between
CMS on/off toggle key C.
Note:
This node is key protected and only available,
when the Color Management option has been
purchased.
Note:
The toggle on/off feature for ‘Deinterlace’,
‘Sharpen’ and CMS only works in the
processed view!
17
The File Menu 3.
3 The File Menu
‘Preferences’ has three tabs:
• Appearance:
to adjust the background, perforation, film,
soundtrack and frame line color in the film view.
Transparency of soundtrack and frame line can also
be adjusted. The general ALICE font can be changed
as well.
• Color Management:
The profile for your workstation monitor can be
selected here. It is necessary to make a selection in
order to use the ´proof´ button. Settings for the out-ofgamut display can also be modified in this dialog
(see chapter Color Management for Video look for
more detailed information).
• Network:
Available DVS hard disk recorders as well as
appropriate network timeouts can be determined in
this dialog (see chapter 4.4 Accessing DVS Disk
Recorders for more detailed information).
18
• ‘Save configuration as…’
will open the file menu. The actual image processing
configuration can be saved without leaving ALICE.
• ‘Save job as…’ will save the actual job (including all
settings from the ALGUI) without leaving ALICE. You
will first be asked to save the image processing
configuration file for that new job and then be
prompted to save the job.
Note:
JPEG image saves the view as displayed, with
a size according to the present magnification
factor.
TIFF images are always saved in the true image
size, regardless of the magnification factor.
They also preserve the internal data range
used, so images with bit depth less than 16
will appear dim as TIFF files.
• Choose ‘Exit and save configuration’
or close the ALICE window with the X
to save the image processing configuration file and
exit ALICE.
The File Menu 3.
• ‘Select sequence’:
The file browser opens and the sequence can be
selected in the display. This change will also be
returned to the ALGUI, if ALICE is left with saving.
• ‘Save view as…’
is used to save the current view as a
- JPEG-image (8bit uncompressed or compressed)
with overlays, if activated or a
- TIFF-image (8 or 16 bit) without overlays.
Overlays are the ‘projector mask’ and the ‘save title
area’.
19
Configuration 4.
4 Configuration
4.1 Naming Conventions in ALICE
On startup, ALICE analyzes all configuration files, directories
and environment variables relevant for recording. In
addition to the information stored in the files, there are
some conventions for naming files. These are relevant
for ALICE only:
Cinemascope geometries
Geometry files with “CS” (in capital letters) in their file
name are assumed to define cinemascope geometries,
thus causing the recorded image to be warped for
anamorphic projection.
Example:
20
Format:
xSize:
ySize:
xOffset:
CS_2K1828x1556
1828
1556
220
yOffset:
xOrigin:
yOrigin:
pitch:
pullDown:
0
1797
2514
1200.0
18960
Geometry files named ‘ipfullap*.cfg‘ are used as
fullap geometries for intermed positive recording. For
each supported pitch there must be one (and not more
than one) ip fullap geometry file. ALICE is installed with
ip fullap geometries for all supported pitches.
Example:
Format:
xSize:
ySize:
xOffset:
yOffset:
xOrigin:
yOrigin:
pitch:
pullDown:
2Kipfullap
2048
1583
0
0
1797
2352
1200.0
18960
Loader LUTs for Color Management
(see also chapter 5)
Loader LUTs are used to convert images to cineon code
values prior to recording. Since the cineon conversion is
built in the ICC profiles used for the Color Management,
Color Management will fail if incorrect loader LUTs are
selected. Therefore, ALICE automatically selects the
appropriate loader LUT if Color Management is turned
on. They are distinguished from other loader LUTs by
starting their name with CMS. If there is more than one
CMS LUT for a bit depth, the user can choose between
these LUTs, but will be prevented from selecting other
LUTs. ALICE is installed with CMS loader LUTs for each
bit depth, named cms08.lut, cms10.lut, cms12.lut and
cms16.lut.
Note:
Configuration 4.1.
Inter Positive fullap geometries
Do not change the loader LUT in the ALGUI, if
Color Management is selected.
21
Configuration 4.2.
22
4.2 Input Format File Specification
Location of input format file
Syntax of input format file
The fully qualified path and filename of the input format
file is specified in the environment variable ALICE_
INPUT_FORMAT_FILE.
The suggested location is
‘c:\al\alice\config\aliceInputFormats.cfg‘.
The syntax of the input format configuration file follows
the general syntax of ARRILASER configuration files, as
for example the film format file. Each entry defines a
valid input format that is a pixel aspect (pixel width/
pixel height) associated with an image size. Whenever
images of this size are selected, ALICE displays a
choice of pixel aspects, denoted by names, in the “Input
Format” drop down list. Instead of giving image width
of height in pixels, the keyword “any” denotes any
arbitrary width or height. Definitions using the keyword
“other” are selectable if (and only if) no other entry
matches the current image size.
# examples of entries for images scanned from
# cinemascope film, thus having a pixel aspect
# of 1:2 :
imageformat: 2k_cinemascope
xSize
: 2048
ySize
: 1556
pixelAspect : 0.5
ALICE uses the following internal rules to determine the
list of input formats:
It internally maintains a list of input formats, consisting
of the entries of the user defined file followed by
predefined HD and SD formats. For any given input
image, each format matching the size of the image is
displayed in the input format panel. If no format is
found in both the user defined and the internal list, a
generic format with pixel aspect 1.0 is assumed.
Configuration 4.2..
################################################
# ARRILASER ALICE Input Format Configuration File #
#
ARRI Film & TV
#
################################################
imageformat: generic_cinemascope
xSize
: any
ySize
: any
pixelAspect : 0.5
# PAL size image, but with square
# pixels
imageformat: PAL_square
xSize
: 720
ySize
: 576
pixelAspect: 1.0
23
Configuration 4.3.
24
4.3 Fine-tuning ALICE
Memory Footprint
Multi Threading
The amount of memory ALICE consumes depends on the
maximum image size to be processed, and the maximum
size of its internal image cache.
Besides running parallel to image loading and recording,
the image processing can operate multi-threaded to make
optimal use of the dual CPU system.
The image cache limit can be influenced by the
environment variable ALICE_MEM_FRACTION.
Its value is the percentage of the memory marked available to
the application by the operating system. Default is 0.25,
meaning that a quarter of the memory is the upper limit of
the image cache. Note that this is the image cache only,
not the total memory footprint of the application. The
environment variable can be set in
‘c:\cshell\login.csh‘.
When running ALICE at the same time as recording on
the same host computer, multi-threading can be switched
off by setting ALIP_THREADS to 0.
This affects both ALICE as well as image processing for
recording. Setting ALIP_THREADS to 1 turns on multithreading, while setting it to “auto” causes the multi
threading to be turned on, but to be disabled it temporarily
if both ALICE and aldaemon are running at the same time,
to allow interactive working with ALICE while computing
data-intensive recordings. The auto setting is also the
default if the environment variable is not set. The
environment variable can be set in
‘c:\cshell\login.csh‘.
Together with ALICE comes the possibility to directly access
DVS HDTV and SDTV disc recorders. Direct access to disc
recorders is also possible via the command line interface
(CLIF).
The direct frame access uses the DVS API, and does not
need the DVS virtual file system to be installed. Frames
are accessed as raw YUV data, and converted to RGB
by the ARRILASER software. The conversion follows the
DVS SMPTE274cgr matrices, thus converting the video
save range into full 16 bit range.
4.4.1 Browsing Disc Recorders
To make disc recorders visible in the sequence dialog
panels, define their host names or ip addresses in the
‘preferred disc recorders‘ section within the ‘network‘ tab
in ALICE preferences. The entry is a comma separated list
of the disk recorders. Disk recorders can be specified by
ip addresses or by name. If specifying names, make sure
there is a domain name server entry for the disc recorders,
or list them in the windows host file
‘c:\winnt\system32\drivers\etc\hosts‘.
Configuration 4.4.1.
4.4 Accessing DVS Disk Recorders
Since the conversion is done at a very early processing
stage, the images are seen by the ARRILASER software
as 16 bit RGB images. They also require 16 bit LUTs for
recording, regardless of being stored as 8 or 10 bit
YUV on the disc recorder. Also, YUV data exported
from the disc recorder as YUV16 can be read, if given
the file extension ‘.yuv16‘.
25
Configuration 4.4.2.
4.4.2 Network Timeouts
4.4.3 Partition Change Policy
Whenever browsing file servers or disc recorders with
the ‘Open Sequence‘ dialog in ALICE, or the ‘Browse”
dialog in the ALGUI, waiting for inactive servers can be
annoying. Therefore timeouts can be adjusted in the
network tab  photo of the preferences panel of
ALICE.
On DVS disc recorders, frames of different sizes are stored
in different partitions. Only one partition can be active
at a time, and only frames on active partitions can be
accessed.
When accessing a DVS disc recorder, the check if the
recorder is reachable is done by sending a ping request
to its host. A value of 0 disables checking, connections
to unreachable disc recorders will then timeout by the
DVS defaults.
The timeout is ignored whenever loading images from
the disc recorder, both by ALICE and CLIF. Therefore, it
does not affect recording.
26
Since changing the active partition will prevent all other
applications and real time operations to be stopped, the
ARRILASER software can be allowed or forbidden to
automatically switch to the partition it needs.
If the environment variable AL_DR_PARTITION_CHANGE
is set to 1, both CLIF and ALICE will switch partitions
without notice. If unset or set to 0, CLIF will never
change partitions, while ALICE will ask the user. The
environment variable can be set in
‘c:\cshell\login.csh‘.
Frames on a disc recorder can be accessed by the
alexpose command as files, using the protocol-like
filename convention:
‘dr://<host name>/<partition name>/<clip
name>/<frame number>‘
e.g.
‘dr://mydiscrecorder/PART1/testclip/42‘
means frame 42 within the clip testclip. Frame
enumerations starts with frame 0.
Note:
This is a name convention built in the CLIF and
ALGUI software, not a protocol. Therefore, no
extra drives have to be installed to use this
feature.
Although the DVS software allows the creation
of partition and clip names containing ‘/‘ or
‘\‘, these will not work. The reserved clip
name ‘.‘ (a single dot) shall also be avoided.
Configuration 4.4.4.
4.4.4 Command Line Interface Syntax
Omitting the clip name addresses the complete
partition, e.g.
‘dr://mydiscrecorder/PART1/500‘
27
Color Management 5.
28
5 Color Management for Video Look
5.1 Operation from ALICE
5.1.1
Configuration of CMS node in ALICE
• Choose monitor profile ‘sony_hd‘ from the list
beside M
• Choose print film profile vision from the list beside P
• Choose soft clip parameter from the list beside clip
If you have your own ICC profiles, copy them into the
folder ‘c:\al\ipconfig\icc‘. After restarting ALICE
they will appear in the profile selection list beside M
and P.
As the color gamuts of film and monitor are different,
not all colors that are visible on the monitor can be
reproduced on film. In order not to lose too much detail
in those areas, it is required that either the lightness or
the chromaticity of these areas is reduced.
In the list of soft clips a preselection of recommended
soft clips can be found. As using a soft clip will not only
affect the out-of-gamut colors, but also the colors that
are just within the gamut, the lowest possible soft clip
should be taken.
The strength of the softclip is dictated by the out-ofgamut colors in the sequence to record. For judging the
softclip, use the proof and the gamut function in the
process view ( see 5.1.3 ).
Color Management 5.1.2
5.1.2 Soft clip Parameter
29
Color Management 5.1.3.
Note:
• Go to file-preferences-Color Management. Choose
workstation profile: ‘sony_hd.icm‘.
There it can be judged, if the loss of resolution in those
areas is acceptable, or not. If not, a soft clip can be
applied. Using a soft clip, it is recognizable, that more
colors are different to the original, but at the same time
more detail can be achieved in back.
5.1.3 Display settings
Proof:
Since the color profiles directly generate cineon data,
judging the effect of the Color Management on the
screen can be difficult. Therefore, the proof mode
allows for simulating the appearance of the recorded
image on the workstation monitor.
• To use the proof-mode, an ICC profile for the monitor
has to be selected in preferences.
30
It is also handy to select the HDTV monitor as
workstation monitor, regardless of the fact that
it is not a HD monitor, since this display allows
checking the effect of clipping out-of-gamut
colors easily by using the ‘C’ toggle key.
Gamut:
The out-of-gamut colors can also be indicated separately, if
the gamut box is tocked. This will highlight the areas
which are out-of-gamut.
Be aware that in these areas clipping can occur.
These areas can be reduced by changing the soft clip
parameters. The way of highlighting can be modified in
the preferences-Color Management dialog. There the color
fixed color:
All out-of-gamut pixels are drawn with the out-of-gamut
color selected in preferences.
blend to fix color:
The color of all out-of-gamut pixels is smoothly blended
with the out-of-gamut color selected in preferences. The
mixing ratio depends on the distance of the color to the
gamut, so that colors being far outside the film gamut
finally are displayed in the out-of-gamut color only.
color distance mask:
In gamut pixels are displayed as gray, while out-ofgamut pixels are blended between the gray and the
original color. The more saturated a color appears in
this view, the more it is out-of-gamut. Note that since the
blending is done between the gray and the original
color, turning proof on has no effect herewith.
Color Management 5.1.3.
in which those areas are indicated can be choosen
(preferable a color which is not so present in the images)
and how to show the distance of those colors to the gamut.
31
Color Management 5.2.
5.2 Configuration
5.2.1 Monitor Setup
5.2.2 Film Setup
Calibration of the HD class A reference monitor
The vision print film profile is established under the
following circumstances:
The HD Monitor that has been used for the color timing
shall be calibrated according to the following guidelines:
• The color temperature shall be 6500K
• 100% white shall be at a luminance of 80 cd/m2.
• 20% gray shall be at a luminance of 2.2 cd/m2
32
Y
U
V
20% gray
2.2 cd/ m2
240
512
512
100% white
80 cd/m2
940
512
512
Note:
• Recorder calibrated to carlos.aim
• Printed on Kodak Vision print stock
• LAD frame (Aqua 0015) printed to
1.09 1.06 1.03 densities
The following two test images are needed for the
calibration procedure:
calibration image luminance
• Recorded on Kodak 5242 intermediate film stock
We recommend the use of a high quality color
calibration sensor, e.g. a Philips PM 5639.
The CMS node syntax
The Color Management node is part of the ARRILASER
image processing system. It allows the use of all features
of the Color Management through its scripting interface.
Please refer to chapter 5.5, Image Processing Software
Engine of the ARRILASER manual for detailed description
of the image processing itself.
The CMS node creates a 3D lookup table from the ICC
profile specified as monitor and recorder profile.
The monitor profile is taken as input profile, the recorder
profile as output profile.
An optional gamut compression can be activated by
specifying one of the presets defined in the soft clip
configuration file.
Also, the rendering intent can be influenced by specifying
either ‘absolute’, ‘relative’, ‘perceptual’ or ‘saturation’.
For a detailed explanation of rendering intents refer to
the ICC home page www.color.org. The only intent
supported by ALICE is ‘absolute’.
Color Management 5.2.3.
5.2.3 Color Management Node
33
Color Management 5.2.3.
34
Node type identifier and node arguments
The Color Management node is identified by the
keyword ‘CMS’.
Argument
Type
Default
monitor profile
string
-
ICC profile to be used
as monitor profile
recorder profile string
-
ICC profile to be used
as recorder profile
soft clip
-
soft clip parameters
to be used (optional)
intent
string
string
-
Example:
# example configuration file showing
# the use of the Color Management node
# with default settings, as used in ALICE
Description
rendering intent
to be used (optional)
node: CMS
monitorprofile: hdmonitor.icm
recorderprofile: arrilaser.icm
# example configuration file showing
# the use of the Color Management node
# with soft clip
node: CMS
monitorprofile: hdmonitor.icm
recorderprofile: arrilaser.icm
soft clip: weak
Syntax of soft clip configuration file
Colors outside the recorder gamut cannot be recorded
without changes, since they do not exist on film. By
default, these colors are hard clipped into the recorder
gamut. To smoothly clip these colors, a compression of
the monitor gamut has to be done. The strength of the
compression can be controlled by the parameters given
in the soft clip configuration file. This chapter explains
the syntax and use of this file.
The syntax of the soft clip configuration file follows the
general syntax of ARRILASER configuration files, as for
example the film format file.
Location of soft clip configuration file
The fully qualified path and filename of the soft clip
configuration file has to be specified in the environment
variable ALIP_SOFTCLIP_FILE (set under ‘c:\cshell\
login.csh‘), and consistently in the ALGUI startup file
‘Arri.txt‘. The default location is
‘c:\al\ipconfig\icc\alsoftclip.cfg‘.
################################################
#
ARRI Film & TV
#
################################################
# example of an entry using the same settings
# for all colors
softclip: all_the_same
dL: 25%
dC: 25%
# example of color specific entry
softclip: different
dL: 25%
dC: 25%
Color Management 5.2.4.
5.2.4 Soft clip Configuration File
dC.R 10%
dL.M 10%
35
Color Management 5.2.4
For each entry in the soft clip configuration file, the
following parameters are valid:
soft clip
name of the setting, used as value of soft clip parameter of the CMS node. Example: “mysoftclip”.
DL
dC
dL.R
dL.G
dL.B
dL.C
dL.M
dL.Y
dC.R
dC.G
dC.B
dC.C
dC.M
dC.Y
luminance difference, used for each color if not specified color specific
chroma difference, used for each color if not specified color specific
luminance difference for red
luminance difference for green
luminance difference for blue
luminance difference for cyan
luminance difference for magenta
luminance difference for yellow
chroma difference for red
chroma difference for green
chroma difference for blue
chroma difference for cyan
chroma difference for magenta
chroma difference for yellow
The color specific settings (dL.R , etc.) always take
precedence over the color independent setting (dL),
regardless of the order of the arguments. This means,
there is no difference in specifying e.g. dL.R before or
after dL .
36
Gamut compression can be achieved in general by reducing
the chroma of colors, thus moving colors slightly towards
the gray axis.
In the case of recording CRT monitor images to film, due
to the fact that film gamut reaches its maximum chroma at
lower levels of lightness than the monitor gamut, carefully
reducing lightness also moves colors into the film gamut.
Best results are achieved by balancing chroma and lightness
reduction. The soft clip parameters specify the amount of
change in terms of the perceptual difference between the
two gamut’s, e.g. setting dC.R to 50% reduces red
chroma by 50% of the difference between the pure red
of the monitor and film gamut, respectively.
Both chroma and lightness change depending on hue,
chroma and lightness, so that dark and unsaturated colors
are affected less than bright, highly saturated colors.
For colors at which the film chroma is greater than the
monitor chroma, the chroma difference should be 0 or
negative to gain gamut compression, otherwise gamut
extension would be the effect. This is especially true for
yellow.
5.3 Provided profiles
Provided with the color management are the following
ICC profiles:
profile name:
sony_hd.icm
description:
Sony BVM –D24 class A HDTV studio monitor,
HDTV video safe range
device dependent RGB values:
16 bit RGB values,
representing the SMPTE260M video safe YUV range.
That means:
RGB=0 matches YUV=64,512,512 and
RGB=65535 matches YUV=940,512,512
for 10bit YUV.
Color Management 5.3.
Soft clip parameters demystified
profile name:
vision.icm
description:
Kodak Vision print stock projected by a xenon lamp
37
technical data are subject to change without notice
© ARRI 2003
available languages:
English
ARNOLD & RICHTER CINETECHNIK
Türkenstraße 89 • D-80799 München
Phone +49-089-3809-0 • Fax +49-089-3809-1244
www.arri.com