eBUS SDK Programmer`s Guide

eBUS SDK Programmer`s Guide
PLEORA TECHNOLOGIES INC.
eBUS SDK
Programmer’s Guide
Installing, Uninstalling, and Starting the Software Applications
a
Copyright © 2012 Pleora Technologies Inc.
These products are not intended for use in life support appliances, devices, or systems where malfunction of these products can
reasonably be expected to result in personal injury. Pleora Technologies Inc. (Pleora) customers using or selling these products for
use in such applications do so at their own risk and agree to indemnify Pleora for any damages resulting from such improper use or
sale.
Trademarks
PureGEV, eBUS, iPORT, vDisplay, and all product logos are trademarks of Pleora Technologies. Third party copyrights and
trademarks are the property of their respective owners.
Notice of Rights
All information provided in this manual is believed to be accurate and reliable. No responsibility is assumed by Pleora for its use.
Pleora reserves the right to make changes to this information without notice. Redistribution of this manual in whole or in part, by
any means, is prohibited without obtaining prior permission from Pleora.
Document Number
EX001-017-0001, Version 3.0, 9/17/12
Table of Contents
About this Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
What this Guide Provides. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Related Documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
List of Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Introducing the eBUS SDK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Assumed Knowledge. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Technical Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
GigE Vision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
GenICam . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Supported Integrated Development Environments (IDEs), Compilers, and
Operating Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
eBUS SDK Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Sample Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Sample Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Accessing the Sample Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Application Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
API Class Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Design and Development Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Using the eBUS SDK API . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Basic Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Advanced SDK Functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Window UI Components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
System Level Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Bandwidth Overhead Calculation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Single Ethernet Frame Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Calculating Ethernet Bandwidth. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
List of UDP Ports on the GigE Vision Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Host-Side Port Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Building and Distributing an eBUS SDK Application . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
eBUS Driver Installer API . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
i
Appendix A — eBUS SDK Primitives and Classes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Appendix B — Layered Representation of the eBUS SDK . . . . . . . . . . . . . . . . . . . . . . . 83
Appendix C — log4cxx Facility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
Reference: C++ eBUS SDK and .NET SDK Comparison . . . . . . . . . . . . . . . . . . . . . . . . 87
Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Enumeration Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
Error Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
Enumerators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Collections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Callbacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
Technical Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
ii
eBUS SDK Programmer’s Guide
Chapter 1
About this Guide
This chapter describes the purpose and scope of this guide, provides a list of complimentary guides,
definitions for some of the terms used in this guide.
The following topics are covered in this chapter:
• “What this Guide Provides” on page 2
• “Related Documents” on page 3
• “List of Terms” on page 3
About this Guide
1
What this Guide Provides
This guide provides information and instructions to developers who are integrating the Pleora
Technologies’ eBUS SDK with their own application in order to communicate with Pleora’s GigE Vision
compliant products. In this guide, you can review information about the underlying technology being
used, along with a high-level view of how the eBUS SDK fits into the system and your application.
Chapters 2-4 provide you with a high-level understanding of the eBUS SDK and of the standards and
technology on which it is based.
Chapter 5, “Sample Code” on page 11, provides a list of sample applications included with the eBUS
SDK installer.
Chapter 6, “Application Development” on page 17, provides you with the basic information you need to
develop an application using the eBUS SDK, including Application Programming Interface (API) class
descriptions and design guidelines.
Chapter 7, “System Level Information” on page 69, describes GigE Vision traffic and bandwidth
implications.
Guidelines for building and distributing user applications on Linux and Window platforms is included
in chapter 8, “Building and Distributing an eBUS SDK Application” on page 75.
The eBUS SDK supports C++, C#.NET, and VB.NET. This guide deals primarily with using the eBUS
SDK in the C++ programming language. For information about the eBUS SDK implementation varies
between C++ and C#.NET, see “Reference: C++ eBUS SDK and .NET SDK Comparison” on page 87.
Developers using this guide should have firm knowledge of PC hardware and software usage and
architecture, along with an understanding of the C++, C#.NET, VB.NET programming languages.
2
eBUS SDK Programmer’s Guide
Related Documents
The eBUS SDK Programmer’s Guide is complemented by the following guides. It is not necessary to read
these documents before using the eBUS SDK, but they do provide additional information.
• GEVPlayer Quick Start Guide
• GEVPlayer User Guide
• eBUS SDK C++API Help File
• eBUS SDK .NET API Help File
The eBUS SDK help files are available in the Windows Start menu (under Pleora Technologies Inc. >
eBUS SDK) or in Linux (/opt/pleora/ebus_sdk/share/doc).
• GigE Vision Specification available from the Automated Imaging Association (AIA) located at
www.visiononline.org.
You must be registered with the AIA and member of the GigE Vision standard group to have access to the
GigE Vision Specification.
• GenICam Specification located at: www.genicam.org.
• Pleora Custom Install Reference Guide
• eBUS Advanced Driver Configuration Reference Guide
• eBUS SDK Linux Software Guide
• Configuring Your Computer and Network Adapters for Best Performance Application Note
• Correcting Firewall Issues Application Note
• Establishing a Serial Bridge Application Note
List of Terms
The following table includes some of the terms, along with their definitions, used in this guide.
Table 1: Terms and Definitions
Term
Definition
API
Application Programming Interface
CCP
Control Channel Privilege
GenICam™
GENeric Interface for CAMeras
Standards group hosted by the European Machine Vision Association (EMVA)
GigE Vision®
GigE Vision is a camera interface standard developed using the Gigabit Ethernet
communication protocol
SDK
Software Development Kit
About this Guide
3
Chapter 2
Introducing the eBUS SDK
The eBUS Software Development Kit (SDK) is the latest software development kit from Pleora
Technologies. Supported under a variety of Linux and Windows operating systems, the eBUS SDK is
fully GigE Vision and GenICam compliant, and allows for rapid development of high-performance
vision applications. The performance of the eBUS SDK can be enhanced by using the eBUS Universal
Pro driver, introduced as part of eBUS SDK 2.0. This driver, compatible with all network interface cards
(NICs), decreases host CPU utilization and is optimized for image acquisition, in comparison to the NIC
manufacturer’s driver.
In addition to communication with video sources such as cameras and other sensors, the eBUS SDK can
manage video receiver devices such as the vDisplay family of GigE Vision devices.
This document focuses on how developers can use the eBUS SDK to allow their application to
communicate with GigE Vision devices.
Assumed Knowledge
This guide is intended for users with knowledge of:
• Computer hardware
• Software usage and architecture
• Computer programming (C++, C#.NET, or VB.NET)
Introducing the eBUS SDK
5
Chapter 3
Technical Overview
Knowledge of the GigE Vision and GenICam specifications is not required when using Pleora products;
however a high-level understanding of these specifications can be helpful to eBUS SDK users.
GigE Vision
GigE Vision is an image interface standard for video transfer and device control over Ethernet networks.
It ensures full interoperability between compliant products from different vendors.
More information about the GigE Vision standard can be found at www.visiononline.org.
GenICam
The goal of GenICam is to provide a generic programming interface for all kinds of cameras. Regardless
of the interface technology (for example, GigE Vision, Camera Link, 1394 DCAM, or USB, and so forth)
or the features that are implemented, the Application Programming Interface (API) should always remain
the same. It is important to note that the eBUS SDK acts like a wrapper around the GenICam library.
The GenICam standard consists of multiple modules according to the main tasks to be solved. The eBUS
SDK uses the following modules:
• GenApi. Used for configuring the camera
• Standard Feature Naming Convention (SFNC). Provides recommended names and types for
common features
More information about the GenICam standard can be found at http://www.genicam.org.
Technical Overview
7
The eBUS SDK provides video player software examples, such as GEVPlayer and NetCommand, that
you can use to access the available XML nodes.
The features exposed in the GenICam interface of a camera, or in other video sources, are controlled by
the camera manufacturer. If the camera you are working with does not expose a particular feature, we
recommend that you contact the manufacturer of that camera who may be able to modify the GenICam
XML file (and potentially the device’s firmware) to include the needed feature.
Supported Integrated Development Environments (IDEs), Compilers, and
Operating Systems
The eBUS SDK supports the following IDEs, compilers, and operating systems:
• An appropriate compiler or integrated development environment (IDE):
• Visual Studio 8 or Visual Studio 9 (if using C++)
• Version 4.0 of the .NET Framework, Microsoft Visual Studio 2010 (or later) (if using C#.NET
or VB.NET)
• Default development toolchain for Red Hat Enterprise Linux 6.1
• One of the following operating systems:
• Microsoft® Windows 7, 32 bit or 64-bit
• Microsoft Windows XP with Service Pack 3 (or later)
• Red Hat Enterprise Linux 6.1 32 bit and 64-bit
•
Depending on the incoming and outgoing bandwidth requirements, as well as the performance of each NIC,
you may require two NICs. For example, even though Gigabit Ethernet is full duplex (that is, it can
simultaneously manage 1 Gbps incoming and 1 Gbps outgoing), the computer’s bus may not have enough
bandwidth to support this. This means that while your NIC can accept four cameras at 200 Mbps each
incoming, and output a 750 Mbps stream on a single NIC (in theory), the NIC you choose may not support
this level of performance. A conventional PCI bus (32-bit at 33 MHz) does not provide enough bandwidth
to transmit a Gigabit Ethernet stream.
If you use the Linux operating system, you must install the SDK as Root.
8
eBUS SDK Programmer’s Guide
Chapter 4
eBUS SDK Architecture
The eBUS SDK can communicate with any GigE Vision-enabled device. The following diagram
demonstrates how the eBUS SDK communicates with a Pleora transmitter connected to a camera.
In this example, a user application using the eBUS SDK acts as a receiver that can be used to control and
stream video images from the GigE Vision transmitter, for example, a GigE Vision camera. When an
application using the eBUS SDK connects to a GigE Vision device, it caches a copy of the XML database
to the local memory. Device commands are sent and received though the GVCP command port. Images
are received through the GVSP streaming port.
eBUS SDK Architecture
9
The eBUS SDK software components interface with the following components
• User application
• Operating system
• Logging (to log event information)
• Driver (to receive image stream data) (optional)
• GenApi (to interpret the GenICam XML file format)
The GVCP/Device Control and GenICam software components make use of the GigE Vision Control
Protocol (GVCP) to communicate and control a GigE Vision Device. The GVSP/Streaming and eBUS
Universal Pro driver software component make use of the GigE Vision Stream Protocol (GVSP) to receive
data blocks such as images from the GigE Vision transmitter device.
10
eBUS SDK Programmer’s Guide
Chapter 5
Sample Code
To illustrate how you can use the eBUS SDK to acquire and transmit images and data, the SDK includes
sample code that you can use. The sample applications can be found in the Samples directory of the eBUS
SDK installation directory.
Most of the sample code provided for the eBUS SDK is written using the C++ programming language,
with the exception of the PvPipelineSample, PvSimpleUISample, and PvTransmitTestPatternSample
applications, which are also available as C#.NET and Visual Basic® .NET (VB.NET) samples.
Sample Code
11
Sample Applications
The following table provides a description of the sample code that is available for the eBUS SDK.
The following samples are available as C# samples in this release. Some samples are also available as
VB.NET samples.
Table 2: Sample Code
Type of application
that is created
Sample code
Function
GEVPlayerSample
Provides the source code for the GEVPlayer
application, used to detect, connect, configure
and display GigE Vision devices and stream
images from GEV transmitter devices.
User interface (UI)-based
NetCommandSample
Provides the source code for the NetCommand
application, used to detect, connect and
configure multiple GEV devices.
UI-based
PvBufferWriterSample
Writes the image content of a PvBuffer object
to the disk as either raw data or a standard
color BMP file.
Command line
This sample is only available for C++.
PvCamHeadSerialComLogSample
Provides basic device control and streaming
capabilities. It also allows monitoring the serial
communication between a Pleora GigE Vision
device and its camera head.
UI-based
This sample is only available for C++.
PvConfigurationReaderSample
This sample code illustrates how to use the
PvConfigurationReader and
PvConfigurationWriter classes. It illustrates
how to persist the state of your applications:
devices, streams configuration, custom strings,
and so forth.
Command line
This sample is only available for C++.
PvDeviceFindingSample
This sample illustrates how to use the
PvSystem, PvInterface, PvDeviceInfo and
PvDeviceFinderWnd classes to detect and
enumerate GigE Vision devices.
Command line
This sample is only available for C++.
PvDualSourceSample
Provides a user interface that lets you view
image streams from two sources
simultaneously.
UI-based
This sample is only available for C#.
12
eBUS SDK Programmer’s Guide
Table 2: Sample Code (Continued)
Sample code
Function
PvGenBrowserWndSample
Displays the GenICam features and settings for
the IP engine to which you connect, and
provides a display window for a single video
source.
Type of application
that is created
UI-based
This sample is only available for C#.
PvGenParameterArraySample
This sample shows how to discover and access
features of a GenApi node map built from a
GenICam XML file programmatically using
PvGenParameterArray.
UI-based
PvMulticastMasterSample
Connects to a GigE Vision device and initiates a
multicast stream (by default it transmits to
239.192.1.1, port 1042).*
UI-based
This sample code is used in conjunction with
the PvMulticastSlaveSample, which listens to
the multicast stream.
PvMulticastSlaveSample
Receives an image stream as a multicast slave
from a multicast master.*
UI-based
This sample is used in conjunction with the
PvMulticastMasterSample, which initiates the
multicast stream.
PvPipelineSample,
PvPipelineSampleVB
In step-by-step order, connects to a device,
displays an image stream, stops streaming,
and disconnects from the device.
UI-based. Available as a
C#.NET sample and a
VB.NET sample.
PvPlcAndGevEvents
This sample shows how to control and handle
PLC states and handle GEV events.
UI-based
This sample is only available for C++.
PvRecoverySample
Performs image acquisition with automatic
recovery support from problems such as
accidental disconnects, power interrupts, and
so on.
Command line
This sample is only available for C++.
PvRGBFilterSample
Grabs an image, converts it to RGB32, applies
filters and saves it disk.
Command line
Places an image in a buffer, converts it to
RGB32, applies an RGB and white balance
filter, and converts the image to a bitmap file.
This sample is only available for C++.
Sample Code
13
Table 2: Sample Code (Continued)
Type of application
that is created
Sample code
Function
PvSerialBridgeSample
Controls a serial device (usually a camera)
connected to a GigE Vision IP Engine from
either a camera configuration application or a
CLProtocol GenICam interface.
Command line
This sample is only available for C++.
PvSimpleUISample,
PvSimpleUISampleVB
Provides a basic user interface to connect to a
device, and receive and display an image
stream.
UI-based. Available as a
C#.NET sample and a
VB.NET sample.
This sample is a good starting point for creating
your own UI project.
PvStreamSample
Creates a PvStream for image acquisition.
Command line
This sample is only available for C++.
14
PvTransmitTestPatternSample,
PvTransmitTestPatternSampleVB
Transmits a test pattern to a given destination.
Command line.
PvTransmitTiledImage
Receives image streams from up to four GigE
Vision compatible transmitters (typically
cameras), tiles them into a single image feed,
and then transmits the tiled image stream to a
given destination.
UI-based
PvTransmitVideoSample
Captures images from either a file (such as a
WMV file) or a capture device (such as a
webcam) using OpenCV, and transmits it to a
given destination.
Command line
PvTransmitScreenSample
Captures the contents of the screen and
transmits it to a given destination.
Command line
PvTransformAndTransmitSample
Receives images from a GigE Vision device,
resamples it (to RGB 24 bits per pixel, 640x480
resolution), prints text on it using OpenCV, and
transmits it to a given destination.
Command line
PvTransmitRawSample
Transmits raw data to a given destination. This
sample code is used in conjunction with the
PvReceiveRawSample application.
Command line
PvReceiveRawSample
Receives raw data from a GigE Vision
transmitter. This sample code is used in
conjunction with the PvTransmitRawSample
application.
Command line
Available as a C++
sample and a .NET (UIbased) sample.
Available as a C++
sample and a .NET
sample.
eBUS SDK Programmer’s Guide
Accessing the Sample Applications
The sample code is installed on your computer in the Pleora Technologies Inc folder, as part of the eBUS
SDK.
To access the sample code (Windows operating system)
• To access the C++ sample code, on the Windows Start menu, click All Programs > Pleora
Technologies Inc. > eBUS SDK > C++ Code Samples Directory.
• To access the sample code for .NET based languages, on the Windows Start menu, click All
Programs > Pleora Technologies Inc. > eBUS SDK > .NET Code Samples Directory.
Windows Explorer opens to the location of the sample code.
You can also access the C++ sample code by navigating to the following location (on the computer running
the eBUS SDK):
C:\Program Files\Pleora Technologies Inc\eBUS SDK\Samples
And the sample code for .NET-based languages is available by navigating to the following location:
C:\Program Files\Pleora Technologies Inc\eBUS SDK\SamplesDotNet
To access the sample code (Linux operating system)
• Navigate to the following location:
/opt/pleora/ebus_sdk/share/samples
Sample Code
15
Chapter 6
Application Development
This chapter provides the information you need to successfully develop an application using the eBUS
SDK’s API.
This chapter is based on using the eBUS SDK in the C++ programming language. If you are creating a
C#.NET or VB.NET application, please consult “Reference: C++ eBUS SDK and .NET SDK Comparison” on
page 87 as you read the information in this chapter.
The following topics are covered in this chapter:
• “API Class Description” on page 18
• “Design and Development Guidelines” on page 19
• “Using the eBUS SDK API” on page 22
Application Development
17
API Class Description
The eBUS SDK API is comprised of a set of classes. The main classes are listed in the following table.
Table 3: API Class Descriptions
Class
Description
PvSystem, PvInterface, PvDeviceInfo
Locates devices on the network.
PvDevice (A class referring to a GigE Vision device)
GigE Vision controller.
PvTransmitterRaw
GigE Vision Transmitter used to transmit GigE Vision blocks.
This feature is GigE Vision compliant.
PvVirtualDevice
Used to provide basic GigE Vision device capabilities, such as
device discovery.
PvGenBoolean, PvGenCommand, PvGenEnum,
PvGenEventSink, PvGenFloat, PvGenFile,
PvGenInteger, PvGenRegister and PvGenString.
Provides access to various GenICam parameters based on the
class type.
PvConfigurationReader, PvConfigurationWriter
Control saving and loading settings and state information. You
can save the following in the same file:
For example, the PvGenBoolean class provides access to
parameters that are either true or false.
• One or more device configurations (all parameters)
• One or more stream configurations
• One or more generic PvGenParameterArray(s) (GenICam
nodemap state)
• User-specific custom strings
PvSerialPort, PvSerialPortIPEngine
Provides access to a serial port on a Pleora GigE Vision device.
PvIPEngineI2CBus (I2C serial controller)
Sends commands to your camera and receives the camera's
replies over an I2C bus connected to a Pleora GigE Vision
device.
Note: This class is not supported by non-Pleora devices.
18
PvBuffer, PvBufferConverter, PvBufferWriter
Controls the memory used to store blocks of data (typically
images) received from the GigE Vision device.
PvFilter, PvFilterDeinterlace, PvFilterRGB
Filters images.
PvStream, PvStreamRaw, PvStreamBase
Receives and controls the data stream from the GigE Vision
device to the PC.
PvStatistics
Provides access to stream statistics.
PvPipeline (PvBuffer management and acquisition
thread)
Makes driving a PvStream easier, but only applies to simple
acquisition scenarios.
PvWnd, PvDeviceFinderWnd, PvDisplayWnd,
PvGenBrowserWnd, PvTerminalIPEngineWnd
Provides access to various user interface classes.
For example, PvDeviceFinderWnd provides a user interface
class that locates GigE Vision devices.
eBUS SDK Programmer’s Guide
Table 3: API Class Descriptions (Continued)
Class
Description
PvString (String class)
Used to input and output strings to/from the eBUS SDK.
Supports both multi-byte and Unicode strings.
PvResult
Provides result information.
For more information, refer to,“Appendix A — eBUS SDK Primitives and Classes” on page 77, or the eBUS
SDK C++ Reference Guide.
“Appendix B — Layered Representation of the eBUS SDK” on page 83 describes how the each class is
organized by library layers.
Design and Development Guidelines
The following table provides important design and development guidelines.
Table 4: Design and Development Guidelines
Design component
Guideline
Asynchronous application
To avoid polling, and blocking, event listening classes are available to asynchronously
handle events.
Logging
During application development and debugging, logging can be an extremely useful
tool. The eBUS SDK makes use of log4cxx libraries to log events to a file or the console.
When an application is deployed, it should perform a minimal amount of application
logging.
• If more logging information is required to debug field issues, the logging level can
be increased as required to isolate the problem. The logging level should be
returned to normal once the problem is resolved. Refer to “Appendix B — Layered
Representation of the eBUS SDK” on page 83 for information on how to change
the logging level.
• Serial commands between the Pleora GigE Vision device and the camera head
can also be monitored through the PvDeviceEventSink Class (Refer to
PvCamHeadSerialComLogSample). Use the PvTerminalIPEngineWnd class to
directly communicate with the camera head.
Competing resources
It is important to choose the appropriate hard drives, NICs and other devices so that
you do not heavily load the system.
Pleora supplies a driver that can be used to improve the transfer between the NIC and
the user application.
Please refer to the Configuring Your Computer and Network Adapters for Best
Performance Application Note, available at the Pleora Technologies Support Center,
for more details.
Application Development
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Table 4: Design and Development Guidelines (Continued)
Design component
Guideline
Coding guidelines
Most methods return a value, which should be checked. Null pointers should always
be checked for reference types. For PvResult, you should test the result for success.
In most cases IsOK() should be used to test against specific PvResult::Code values.
IsSuccess(), IsFailure(), and IsPending() should only be used when queuing a buffer
in a PvStream.
Debugging guidelines
While debugging an application and setting a breakpoint, you might need to increase
the heartbeat timeout so that the GigE Vision device does not think it has lost
communication with the user application. You may either set
DefaultHeartbeatTimeout (before connecting to the device) or
GevHeartbeatTimeout (after connecting to the device) to a high enough value. Refer
to “Appendix B — Layered Representation of the eBUS SDK” on page 83 for more
information.
GEVPlayer
After the eBUS SDK is installed, we recommend that you become familiar with the
sample application, GEVPlayer.
GEVPlayer demonstrates a wide variety of eBUS SDK functionality, including, but not
limited to, image acquisition, serial communication, GenICam control, and event
monitoring. GEVPlayer is included with the numerous other sample applications.
We suggest that you become familiar with the GenICam browser in GEVPlayer. The
browser is the primary tool for controlling the camera and the GigE Vision device
functionality. GEVPlayer provides a solid example of how GenICam features are
modified and updated in a system.
You can customize GEVPlayer to suit your specific needs or create your own
application using the eBUS SDK.
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eBUS SDK Programmer’s Guide
Table 4: Design and Development Guidelines (Continued)
Design component
Guideline
Other sample applications
We recommend that you become familiar with the other sample applications that are
automatically installed in the following directories:
• Windows: C:\Program Files\Pleora Technologies Inc\eBUS SDK\Samples and
C:\Program Files\Pleora Technologies Inc\eBUS SDK\SamplesDotNet
• Linux: /opt/pleora/ebus_sdk/share/samples
The sample applications are installed in these directory locations if your installation
process is using the default installation directory.
These sample applications, along with the source code for the GEVPlayer application,
demonstrate most of the functionality available in the eBUS SDK. The sample
applications are focused on a single concept, which can help you develop a more
complete understanding of that concept.
System performance
considerations
You can take the following steps to optimize system performance:
• Adjust Network Interface Card and driver parameters:
•
Enable jumbo packets especially when using high data rates
•
Increase the Rx Descriptor for the NIC at high block rates
• Increase the number of PvPipeline buffers, which may help when buffer depth is
not large enough (an increase in CPU usage may indicated that buffer depth is
not large enough)
• Optimize PvStream parameters (refer to the Stream Control Application Note
available at the Pleora Technologies Support Center, for more details.).
• Use the eBUS Universal Driver when using large block size at high block rates.
The eBUS Universal Driver is optimized to decrease CPU usage.
The following application notes, available at the Pleora Technologies Support Center,
provide important information you can use to optimize your application with regards
to system performance:
• Stream Control Application Note
• Configuring Your Computer and Network Adapters for Best Performance
Application Note
• Correcting Firewall Issues Application Note
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Using the eBUS SDK API
This section provides information on basic eBUS SDK API services, as well as the more advanced services
and Windows GUI components.
Basic Services
You can use the following basic eBUS SDK API services, as outlined in this section:
• Detecting to GigE Vision devices
• Connecting to GigE Vision devices
• Configuring GigE Vision devices
• Receiving data from a GigE Vision transmitter
Detecting GigE Vision Devices
Detecting GigE Vision devices can be accomplished by:
• Using the PvDeviceFinderWnd UI class
- Or Programmatically using PvSystem, PvInterface and PvDeviceInfo.
You can also use the PvSystemEventSink class to perform a callback function. The
PvSystemEventSink class can be used to notify the application each time a new device is detected
and filter devices accordingly.
To detect a GigE Vision device using the PvDeviceFinderWnd GUI function
1. Create a UI-based GigE Vision device finder, for example a PvDeviceFinderWnd object.
2. Display the dialog box using PvWnd::ShowModal().
3. Retrieve the user’s selection (information about the selected GigE Vision device) using
PvDeviceFinderWnd::GetSelected() to retrieve an instance of PvDeviceInfo.
Code Example
C++
PvDeviceFinderWnd lFinderWnd;
if (! lFinderWnd.ShowModal().IsOK() )
{
return;
}
// When dismissed with OK, the device finder dialog keeps a reference
// on the device that was selected by the user. Retrieve this reference.
PvDeviceInfo* lDeviceInfo = lDeviceFinderWnd.GetSelected();
}
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eBUS SDK Programmer’s Guide
To programmatically detect a GigE Vision device using PvSystem, PvInterface and
PvDeviceInfo
1. Create a PvSystem object (This object represents the computer).
2. Set the maximum time to search for GigE Vision devices using SetDetectionTimeout().
3. Optionally, use a callback to filter out GigE Vision devices or connect to them more quickly.
For more information, refer to PvSystemEventSink.
4. Search for all GigE Vision devices through all available NICs on the PC, using Find().
5. Get the number of NICs on the PC, using GetInterfaceCount().
6. For each NIC on the PC:
• Get the Interface (PvInterface object), using GetInterface().
• Get the number of GigE Vision devices found under the NIC, using
PvInterface::GetDeviceCount().
• For each GigE Vision device:
• Get the GigE Vision device information (PvDeviceInfo object). Use
PvInterface::GetDeviceInfo().
• Test to see if the GigE Vision device is the one you seek, using
PvDeviceInfo::GetMACAddress(), PvDeviceInfo::GetIPAddress(), and other
PvDeviceInfo methods.
• Continue until you find the GigE Vision device you seek.
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Code Example
C++
PvSystem lSystem;
PvResult lResult;
PvDeviceInfo *lDeviceInfo = NULL;
// Find all GigE Vision devices on the network.
lSystem.SetDetectionTimeout( 200 );
lResult = lSystem.Find();
if( !lResult.IsOK() )
{
printf( "PvSystem::Find Error: %s", lResult.GetCodeString() );
return -1;
}
// Get the number of GEV Interfaces that were found using GetInterfaceCount.
PvUInt32 lInterfaceCount = lSystem.GetInterfaceCount();
// Display information about all found interfaces.
// For each interface, display information about all devices.
PvInterface * lInterface= NULL;
for( PvUInt32 x = 0; x < lInterfaceCount; x++ )
{
// Get pointer to each of interface.
lInterface = lSystem.GetInterface( x );
// Get the number of GigE Vision devices that were found using GetDeviceCount.
PvUInt32 lDeviceCount = lInterface->GetDeviceCount();
for( PvUInt32 y = 0; y < lDeviceCount; y++ )
{
lDeviceInfo = lInterface->GetDeviceInfo( y );
// Check if the device is the desired one
}
}
// Connect to the last GigE Vision device found.
PvDevice lDevice;
if( lDeviceInfo != NULL )
{
printf( "Connecting to %s\n",
lDeviceInfo->GetMACAddress().GetAscii() );
lResult = lDevice.Connect( lDeviceInfo );
if ( !lResult.IsOK() )
{
printf( "Unable to connect to %s\n",
lDeviceInfo->GetMACAddress().GetAscii() );
}
}
else
{
printf( "No device found\n" );
}
Connecting to GigE Vision devices
Use the following procedures to connect to a GigE Vision device.
To programmatically connect to an IP engine
1. Select a GigE Vision device.
For more information, see “To programmatically detect a GigE Vision device using PvSystem,
PvInterface and PvDeviceInfo” on page 23.
2. Get a reference to the selected GigE Vision device.
If using PvDeviceFinderWnd, use GetSelected().
3. Connect to the IP engine using PvDevice::Connect().
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eBUS SDK Programmer’s Guide
Code Example
C++
PvDeviceFinderWnd lFinderWnd;
if (! lFinderWnd.ShowModal().IsOK() )
{
return;
}
// When dismissed with OK, the device finder dialog keeps a reference
// on the device that was selected by the user. Retrieve this reference.
PvDeviceInfo* lDeviceInfo = lDeviceFinderWnd.GetSelected();
// Connect to the selected GigE Vision device.
if( lDeviceInfo != NULL )
{
printf( "Connecting to %s\n",
lDeviceInfo->GetMACAddress().GetAscii() );
PvDevice lDevice;
PvResult lResult = lDevice.Connect( lDeviceInfo );
if ( !lResult.IsOK() )
{
printf( "Unable to connect to %s\n",
lDeviceInfo->GetMACAddress().GetAscii() );
}
else
{
printf( "Successfully connected to %s\n",
lDeviceInfo->GetMACAddress().GetAscii() );
}
}
else
{
printf( "No device selected\n" );
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25
To connect with known connectivity information using PvDevice
1. Create a GigE Vision device controller using PvDevice.
2. Connect to the GigE Vision device using Connect(const PvString&,…).
3. The string can contain either any of; an IP address like “192.168.1.100”, a MAC address such as
“00:11:22:33:44:5F” or the device’s name (DeviceUserID) such as “MyDevice”.
Code Example
C++
PvDevice *aDevice = new PvDevice();
PvDeviceInfo lDeviceInfo;
aDevice->Connect("192.168.1.100");
if( !lResult.IsOK() )
{
printf( "PvDevice::Connect Error: %s", lResult.GetCodeString() );
return -1;
}
Connection Heartbeat/Link Status
A heartbeat message is sent periodically from the controller application to the GigE Vision device to
ensure that the connection between the application and the device still exists.
GigE Vision devices are controlled through the primary control channel. In order to control a device, an
application must lock the primary control channel by writing the required information to request either
controlled or shared access to the device using the Control Channel Privilege (CCP) register.
Taking control of a device by locking the CCP register is performed automatically when successfully
connecting a PvDevice to a GigE Vision device using the Connect() method. By default, Connect()
assumes PvAccessControl where other applications can still access the device in read-only mode without
write/control privileges. Other applications can read registers but cannot change the configuration or
request the device to start streaming. Only the application locked on the primary control channel can
perform these actions. When the application is connected as PvAccessControl, the eBUS SDK sends a
heartbeat to the device to keep the control channel active. The application is considered as the primary
one — no other application may control the device.
The GigE Vision device stays locked for that PvDevice until the CCP is released, for example, when
PvDevice::Disconnect() is called, or when no heartbeat has been received from the primary application
within the GevHeartbeatTimeout interval.
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eBUS SDK Programmer’s Guide
If you set a breakpoint in your application, and take time to trace through the code and investigate, you
will find that the heartbeat thread is as idle as the rest of the code. You should consider increasing the
value of the heartbeat timeout when debugging your code to prevent losing the connection when the
debugger stops at a breakpoint. You should set either the DefaultHeartbeatTimeout (before connecting
to the device), or GevHeartbeatTimeout (after connecting to the device), to a high enough value to avoid
losing the connection. Pleora suggests a value of 45000, which gives your application 45 seconds to issue
each heartbeat. The disadvantage of doing this is that if your application crashes, or you abruptly stop
debugging without properly disconnecting the PvDevice (which would have explicitly released the CCP),
it can take the GigE Vision device up to 45 seconds to detect that the controller is disconnected and then
release the CPP. If this happens, you can either wait the 45 seconds, or reset the device by power cycling.
Configuring a GigE Vision Device
The eBUS SDK facilitates the creation of an array representing the device’s GenICam parameters through
the use of:
• PvDevice::GetGenParameters().
• PvDevice::GetGenLink() (can be used to access an array of the PC side parameter settings).
There are also GigE Vision register addressable methods that can be used to control GigE Vision devices
through direct address reads and writes, for example, (PvDevice::ReadMemory() and
PvDevice::ReadRegister()).
Camera control can be accomplished by manipulating features in the GenICam node map, assuming
those features are exposed by the manufacturer.
The sample applications, GEVPlayer, and PvSimpleUI, provide examples of how to control GigE Vision
devices. You can write code similar to the sample code, provided below, to obtain the same results as the
sample applications.
Device Parameter and Stream Control
Use the following procedure to control features.
To control features
1. Get the list of features by using one of the following methods:
• PvDevice::GetGenParameters() (GigE Vision device’s settings)
• PvDevice::GetGenLink() (PC’s communication related settings)
• PvStream::GetParameters() (Image stream settings)
2. Get a reference to the feature using Get().
This returns a PvGenParameter instance.
3. If required, get the feature’s type using PvGenParameter::GetType().
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4. Optionally:
• Get/set the feature’s value. Use the GetValue/SetValue method for the feature’s type (for
example, PvGenInteger::GetValue(), PvGenFloat::SetValue(), and so forth).
• If the feature is a command, activate it using PvGenCommand::Execute().
• Get/set the feature’s value with one method (for example, GetIntegerValue, SetIntegerValue,
ExecuteCommand, and so forth).
Code Example
C++
// Connect to the GigE Vision device.
PvDevice lDevice;
// Connect to device.
…
…
//
// Get device parameters needed to control streaming.
PvGenParameterArray *lDeviceParams = lDevice.GetGenParameters();
// Negotiate the streaming packet size.
lDevice.NegotiatePacketSize();
// Create the PvStream object.
PvStream lStream;
// Open stream - have the PvDevice do it for us.
printf( "Opening stream to device\n" );
lStream.Open( lDeviceInfo->GetIPAddress() );
// Create the PvPipeline object
PvPipeline lPipeline( &lStream );
// Read the payload size from the device.
PvInt64 lSize = 0;
lDeviceParams->GetIntegerValue("PayloadSize",lSize);
// Set the Buffer size and the Buffer count
lPipeline.SetBufferSize( static_cast<PvUInt32>( lSize ) );
lPipeline.SetBufferCount( 16 );
// Increase for high frame rate without missing block IDs.
// Have to set the Device IP destination to the Stream.
lDevice.SetStreamDestination( lStream.GetLocalIPAddress(), lStream.GetLocalPort() );
// IMPORTANT: the pipeline needs to be "armed", or started before
// we instruct the device to send us images.
printf( "Starting pipeline\n" );
lPipeline.Start();
// Get stream parameters/stats
PvGenParameterArray *lStreamParams = lStream.GetParameters();
Continued on next page...
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eBUS SDK Programmer’s Guide
// TLParamsLocked is optional but when present, it MUST be set to 1
// before sending the AcquisitionStart command.
if (lDeviceParams->SetIntegerValue("TLParamsLocked",1).IsOK())
{
printf( "Setting TLParamsLocked to 1\n" );
}
printf( "Resetting timestamp counter...\n" );
lDeviceParams->ExecuteCommand("GevTimestampControlReset");
// The pipeline is already "armed", we just have to tell the device
// to start sending us images.
printf( "Sending StartAcquisition command to device\n" );
PvResult lResult = lDeviceParams->ExecuteCommand("AcquisitionStart");
// Acquire images until the user instructs us to stop
printf( "\n<press the enter key to stop streaming>\n" );
// Tell the device to stop sending images.
printf( "Sending AcquisitionStop command to the device\n" );
lDeviceParams->ExecuteCommand("AcquisitionStop");
// If present reset TLParamsLocked to 0. Must be done AFTER the
// streaming has been stopped.
if (lDeviceParams->SetIntegerValue("TLParamsLocked",0).IsOK())
{
printf( "Resetting TLParamsLocked to 0\n" );
}
// We stop the pipeline - letting the object lapse out of
// scope would have had the destructor do the same, but we do it anyway.
printf( "Stop pipeline\n" );
lPipeline.Stop();
// Now close the stream. Also optional but nice to have.
printf( "Closing stream\n" );
lStream.Close();
// Finally disconnect the device. Optional, still nice to have.
printf( "Disconnecting device\n" );
lDevice.Disconnect();
Programmable Logic Controller (PLC)
Some Pleora devices are equipped with Programmable Logic Controller (PLC) capabilities.
For a complete working sample of how to control the PLC, refer to the PvPlcAndGevEvents sample,
located at C:\Program Files\Pleora Technologies Inc\eBUS SDK\Samples.
• PvPlcAndGevEvents
• PvPlcDelayerSample
• PvRescalerSample
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Device Persistence
To save the device’s settings, including its IP configuration and the device name, you can leverage user
sets, which save this type of information to the device’s flash memory. The IP engine can be configured
so that, at the next power cycle, the device settings are automatically set to the previously saved
information. You can also restore the default settings at next power cycle, or at any time.
The following parameters are always saved persistently and are independent from the user set operations:
• GevPersistentIPAddress
• GevPersistentSubnetMask
• GevPersistentDefaultGateway
• GevCurrentIPConfigurationDHCP
• GevCurrentIPConfigurationPersistentIP
The following code example shows how to access the UserSet parameters.
Code Example
C++
PvString lValue;
PvGenEnum* lPvGenEnum;
PvGenCommand *lPvGenCommand;
// **********************************************************************//
// Save current settings into device flash memory and
// configure the device to restore those setting upon power up
// **********************************************************************//
lDevice.GetGenParameters()->SetEnumValue( "UserSetSelector", "UserSet1" );
lDevice.GetGenParameters()->ExecuteCommand( "UserSetSave" );
lDevice.GetGenParameters()->SetEnumValue( "UserSetDefaultSelector", "UserSet1" );
// ***************************************************************************//
// Reset to the default settings at next power up
// ***************************************************************************//
lDevice.GetGenParameters()->SetEnumValue( "UserSetDefaultSelector", "Default" );
Receiving Data from a GigE Vision Transmitter
This section discusses how data is received from a GigE Vision transmitter, such as a GigE Vision camera.
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eBUS SDK Programmer’s Guide
PvStream and PvPipeline
The PvStream class is used to receive a stream of image blocks flowing from the GigE Vision transmitter
to the computer receiving the images (image receiver).
The image receiver does not have to be the same computer that controls the GigE Vision device.
PvStream is usually only responsible for receiving images and attempting to retrieve buffers. Use
PvDevice to control the device and initiate the image stream acquisition.
PvStream can automatically send packet resend requests to the GigE Vision device, and in some cases
read some configuration registers to find out about device capabilities. However, it does not otherwise
CONTROL the device in any way.
An image stream can be received directly by the PvStream class or by the PvPipeline class. PvPipeline
uses PvBuffers that are handled by PvStream, which hides some of the complexity of buffer management
allowing for simpler code. If you want more control over the system, you can use PvStream directly.
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The following diagram illustrates how blocks are received from the transmitter.
GigE Vision stream packets are received by the data receiver and assembled to recreate a block (typically,
an image) in each PvBuffer (illustrated as a block). The RetrieveBuffer() method can then be used to
retrieve the next available PvBuffer. Once the application is done with the PvBuffer, it re-queues the
PvBuffer to the PvStream object to be re-used for another block.
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eBUS SDK Programmer’s Guide
Using PvStream
The following section describes how to configure a PvStream and a PvBuffer to receive through the data
receiver from the camera. The application must ensure that sufficient free buffers are available in the
stream so that the data receiver does not overflow. For optimal performance and to avoid losing images,
at least two buffers should be available in PvStream at all times. Add buffers immediately after removing
them, (see PvStreamBase::QueueBuffer() in the eBUS SDK API Help File), using
GetQueuedBufferCount(). In general, if images are received at 30 FPS, four buffers should be sufficient,
but this depends on various factors. The number of buffers varies based on the incoming data rate, data
size, processing to be done by the application, and speed of the PC (this includes CPU speed, memory
bus speed, and NIC to CPU interface speed). It is a good idea to increase the buffer count when handling
high frame rates, especially when missing block IDs are being observed.
To use PvStream to receive images
1. Create a stream object (PvStream object) using the PvStream constructor.
2. Open the stream using Open().
3. Create and configure buffers.
For more information, see the PvBuffer Class topic in the eBUS SDK API Help File.
Note: The eBUS SDK can allocate the memory, or you can attach to an existing memory pool. If
you are using an external memory pool, you can use PvBuffer::Attach(). For more information, see
PvBuffer::Attach() in the eBUS SDK API Help File.
4. Create a loop using your own code. In the loop:
• Queue buffers up to the maximum number of GetQueuedBufferMaximum() using
QueueBuffer.
• Retrieve a buffer and immediately queue another (to maintain GetQueuedBufferMaximum()
buffers in the queue). Use PvStreamBase::RetrieveBuffer() and PvStreamBase::QueueBuffer().
• Optionally, image stream statistics can be accessed. For more information, see the PvStatistics
topic in the eBUS SDK API Help File.
• Process the image contained in the PvBuffer.
• Test the success of the image acquisition. Use the aOperationResult parameter in
PvStream::RetrieveBuffer() or PvBuffer::GetOperationResult().
PvBuffer::GetOperationResult() lets you see the state of the buffer before trying to read the
data (image) where you may, for example, be missing packets.
• Retrieve a PvImage interface to the buffer using GetImage().
• Process the image using your own code. You can process the image in place by using:
• PvImage::GetAcquiredSize()
• PvImage::GetHeight() and PvImage::GetWidth()
• PvImage::GetOffsetX() and PvImage::GetOffsetY()
• PvBuffer::GetDataPointer()
• Continue queuing, retrieving, and processing buffers.
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• For optimal performance and to avoid losing images, at least two buffers should be available in
PvStream at all times. Add buffers immediately after removing them, (for more information, see
PvStreamBase::QueueBuffer() in the eBUS SDK API Help File), using
GetQueuedBufferCount().
• Optionally, get statistics about the image stream performance using GetParameters() and
PvGenParameterArray.
5. Close the stream using PvStream::Close().
Sample Code
• To view sample code for PvStream, view the PvStreamSample file located at C:\Program Files
(x86)\Pleora Technologies Inc\eBUS SDK\Samples.
Using PvStream and PvPipeline
The following section describes how to use PvStream and PvPipeline to receive PvBuffers from the data
receiver.
PvPipeline provides an intuitive interface on top of a PvStream or PvStreamRaw. The pipeline allocates
buffers, manages buffer size, and runs threads dedicated to pulling buffers out of a PvStream and making
them available to your application while ensuring sufficient buffers are queued in a PvStream.
When the output-queue of the PvPipeline is full, buffers are dropped and recycled as available buffers to
be queued in PvStream. Thus, it is important for the application to ensure that the PvPipeline is serviced
regularly.
Similar to PvStream, the PvPipeline is only responsible for receiving data. Starting the PvPipeline only
arms it; PvPipeline does not interact with the IP engine in any way.
Use PvDevice to control the device and initiate image acquisition.
To use PvPipeline to receive images
1. Create a stream object (PvStream object) using the PvStream constructor.
2. Open the stream using PvStream::Open().
3. Create a multi-buffer controller (PvPipeline object).
4. Optionally, set the buffer’s size using SetBufferSize(). The size to set is determined by reading the
GevPayloadSize on the device after setting Width, Height, and PixelFormat. (For more
information, see “Configuring a GigE Vision Device” on page 27.)
5. Optionally, set the number of buffers in the pipeline using SetBufferCount().
6. Start the Pipeline using PvPipeline::Start().
7. Get one or more image buffers (PvBuffer object) using RetrieveNextBuffer().
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eBUS SDK Programmer’s Guide
8. If the PvResult returned from RetrieveNextBuffer() is successful then, process the image in
PvBuffer.
• Retrieve a PvImage interface to the buffer by using GetImage().
• Test the success of the image acquisition. Use the aOperationResult parameter in
PvPipeline::RetrieveNextBuffer() or PvBuffer::GetOperationResult() to test the acquisition
operation on the PvBuffer.
• Process the image using your own code. You may process the image in place, if you wish by
using:
•PvImage::GetAcquiredSize()
•PvImage::GetHeight() and PvImage::GetWidth()
•PvImage::GetOffsetX() and PvImage::GetOffsetY()
•PvBuffer::GetDataPointer()
9. Continue retrieving, processing, and returning image buffers. Use RetrieveNextBuffer() and
ReleaseBuffer().
Failure to return the image buffer to the pipeline using ReleaseBuffer() can cause the PvPipeline to starve
from lack of buffers. In general, (30 FPS), four buffers should be sufficient, but this depends on various
factors. The number of buffers varies based on the incoming data rate, data size, processing to be
completed by the application, and speed of the computer (this includes CPU speed, memory bus speed,
and NIC-to-CPU interface speed). You should increase the buffer count when handling high frame rates,
especially when missing block IDs are being observed.
10. Stop the image acquisition using Stop().
Sample Code
• To view sample code for PvPipeline, view the PvPipelineSample file. For information about
accessing the sample code, see “Accessing the Sample Applications” on page 15.
Number of Buffers Queued into Data Receiver
In the eBUS SDK with the introduction of the eBUS Universal Pro and a new data receiver, the maximum
number of buffers that can be queued into the data receiver has been increased to 64. You should always
confirm this number by calling GetBufferQueuedMaximum().
If you are using PvPipeline, this is automatically handled for you, where “n” is the number of buffers used
by the PvPipeline. It is configured with the PvPipeline::SetBufferCount() method and the default buffer
count is 16.
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Driver and Stream Settings
PvStream makes use of the IP stack to retrieve IP (GVSP) packets which make up a particular block
(typically an image). Depending on the system requirements, it is important to note that it may be
necessary to tune the system for optimal performance.
Table 5: Driver and Stream Settings
Recommended action
Benefits
For Windows OS
Install Universal Pro Filter Driver
Decreases CPU usage
Enable Jumbo Packet option on NIC
Decreases network overhead, and CPU usage (lowers the number of
interrupts).
Set large Rx Descriptor on NIC
Decreases likelihood of losing packets
Interrupt Moderation
Allows the adapter to moderate interrupts.
For Linux OS
Set Jumbo Packets on NIC
Important when large blocks are used > 1500 bytes
Set large Rx Descriptor on NIC
Decreases likelihood of losing packets
Set large Rx Socket size on IP stack
Decreases likelihood of losing packets (use set_socket_buffer_size.sh)
Set root as running level (optional)
Running as root switches the schedulers you are running on Linux.; the
application runs in a more deterministic and stable fashion.
Some communication settings are available in order to modify the behavior of the image stream.
GEVPlayer’s Image Stream Control window is a good place to become familiar with the features and their
descriptions.
All parameters and statistics are accessed through PvStream::GetParameters(). The stream control
configuration settings differ depending on the driver being used.
Stream Statistics
The eBUS SDK stream statistics provides the application information such as image count, average
bandwidth, and missing block IDs, for example. The statistics for a PvStream object are provided through
the GenICam interface.
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eBUS SDK Programmer’s Guide
Code Example
C++
//****************************************************************************//
// Retrieve the up-to-date statistics values at any time you like
//
//****************************************************************************//
PvInt64 lV1, lV2, lV3;
lStream.GetParameters()->GetIntegerValue( "ImagesCount", lV1 );
lStream.GetParameters()->GetIntegerValue( "BytesCount", lV2 );
lStream.GetParameters()->GetIntegerValue( "BlockIDsMissing", lV3 );
printf( "Images count: %lld bytes count %lld missing block IDs: %lld",lV1, lV2, lV3 );
• The stream statistics are cumulative values which are reset by executing the PvStatistics::Reset
command.
• Even though the example above shows how to retrieve integers, some statistics are expressed as
floating point values. To handle these statistic types, use PvGenFloat and
PvGenParameterArray::GetFloatValue().
Application Development
37
Block Acquisition
Blocks (image) may be received by one or multiple receivers. In the case of one receiver, a unicast
connection is sufficient (point to point). In the case of multiple receivers, an IGMP-compliant switch can
be used to multicast the same block (image) to multiple receivers.
Three types of acquisition are possible using the eBUS SDK,
• Unicast Acquisition
• Remote Unicast Acquisition
• Multicast Acquisition
Unicast Acquisition
1. Once connected, get the GigE Vision device’s GenICam parameters using
PvDevice::GetGenParameters().
2. Configure how the GigE Vision device grabs images. Relevant GenICam features include:
• Width
• Height
• PixelFormat
3. Configure your PC(s) to receive blocks through PvStream.
4. Configure your PvDevice's streaming destination using PvDevice::SetStreamDestination().
The parameters passed identify the location to which the image data should be transmitted. The
destination consists of an IP address (unicast or multicast) and a port number.
5. Lock the interface for streaming. Set TLParamsLocked feature of the GigE Vision device’s
GenICam interface to “1”.
All Pleora devices use TLParamsLocked as an Integer, some third-party GigE Vision devices define it as a
Boolean.
GenICam has the concept of locking features using the TLParamsLocked node. Any feature can link to this
node. When TLParamsLocked is set to 1, all features linked to this feature cannot be changed. As an
example of a typical use case, you can set TLParamsLocked to 1 before AcquisitionStart and 0 after
AcquisitionStop. This protects the streaming related parameters from being changed during streaming.
The features linked to this node are determined by the GenICam XML supplied by the device manufacturer.
6. Use the AcquisitionStart function of the GigE Vision device’s GenICam interface to start the image
stream from the device.
7. When required, use the AcquisitionStop feature of the GigE Vision device’s GenICam interface to
stop image acquisition.
8. Set TLParamsLocked feature of the GigE Vision device’s GenICam interface to 0.
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eBUS SDK Programmer’s Guide
Code Example
C++
// Connect PvDevice as above
// Open PvStream as above
// ...
// Instruct device to stream to our PvStream object
lDevice.SetStreamDestination(
lStream.GetLocalIPAddress(),
lStream.GetLocalPort() );
// Read payload size from the devices GenICam interface. Optional, could also be
// computed locally or automatically handled by the PvPipeline after missing a frame
// with BUFFER_TOO_SMALL
lDevice.GetIntegerValue("PayloadSize", lPayloadSizeValue);
// Instantiate, start pipeline
PvPipeline lPipeline;
lPipeline.SetBufferSize( lPayloadSize );
lPipeline.Start();
// Lock device parameters
lDevice.SetIntegerValue("TLParamsLocked", 1);
// Instruct device to start acquisition
mDevice.ExecuteCommand("AcquisitionStart");
// Acquisition loop
while ( ... )
{
PvBuffer *lBuffer = NULL;
// Retrieve buffer from pipeline
PvResult lResult =
lPipeline.RetrieveNextBuffer( &lBuffer );
// If retrieve succeeded
if ( lResult.IsOK() )
{
if ( lBuffer->GetOperationResult.IsOK() )
{
//
// Do something with the buffer…
//
}
// IMPORTANT!!
lPipeline.ReleaseBuffer( lBuffer );
}
}
// Instruct device to stop acquisition
mDevice.ExecuteCommand("AcquisitionStop");
// Unlock device parameters
lDevice.SetIntegerValue("TLParamsLocked", 0);
// Cleanup
lPipeline.Stop();
lStream.Close();
lDevice.Disconnect();
Sample Code
• To view sample code for PvPipeline, view the PvPipelineSample file. For information about
accessing the sample code, see “Accessing the Sample Applications” on page 15.
Application Development
39
Remote Unicast
A remote unicast setup is made up a management entity (PC) configuring a GigE Vision transmitter. A
receiver then connects with a unicast address to the unit and receives the blocks.
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eBUS SDK Programmer’s Guide
Code Example
C++
//**************************************************************************//
// Step 1: Set the Communication parameters before connecting //
//**************************************************************************//
// For an example for setting DefaultHeartTimeout, see the
// “Access Communication Settings” section
//**************************************************************************//
// Step 2: Connect to device
//**************************************************************************//
PvDevice lDevice;
// method 1: Connect using the device info lDeviceInfo obtained in the
// "Detect and Select Device" section
lDevice.Connect(lDeviceInfo, aAccessType );
// method 2: Connect using the IP Engine's IP address; in this example it is
// "192.168.1.128"
lDevice.Connect("192.168.1.128", aAccessType );
// method 3: Connect using IP Engine's MAC address; in this example it is
// “00:11:1C::00:76:0A” The format "00-11-1C-00-76-0A also works.
lDevice.Connect("00:11:1C:00:76:0A", aAccessType );
//**************************************************************************//
// Step 3: Set up the stream packet size. Only the device controller can do
// this. If you skip this step, the current value of GevSCPPacketSize on
// the device is used.
//**************************************************************************//
// Option A: Perform auto negotiation to find largest packet size that can be
// used on the network link. At the completion of this call, GevSCPPacketSize
// is set to the largest possible packet size; if NegotiatePacketSize() fails,
// it is set to 1476 lDevice.NegotiatePacketSize( 0, 1476 );
//
//
//
//
Option B: Set a value that you know works well. In the case of multicasting
or remote unicast, this is good practice, as auto negotiation does not test
all stream receivers to determine the largest packet size that can be used
lDevice.GetGenParameters()->SetIntegerValue( “GevSCPSPacketSize”,1476 );
//**************************************************************************//
// Step 4: Set up proper streaming networking topology
//**************************************************************************//
//
//
//
//
//
Scenario 2: Remote unicast controller -- this application controls the
device and does not receive the image data. In this example the stream goes
to destination IP address 192.168.1.89 and port 2001. As this application
does not receive image data, there is no need to create a stream object
lDevice.SetStreamDestination( "192.168.1.89" , 2001 );
// Scenario 3: For Remote unicast data receiver -- this application does not
// control the device and only receives the image data. It expects image data
// coming in from the NIC with IP address: 192.168.1.89 on port 2001
// This application does not need to connect to the device, but still needs to
// know the device's IP address to open the stream
lStream.Open(lDeviceInfo ->GetIPAddress(), 2001, 0, "192.168.1.89" );
Application Development
41
Multicast Acquisition
A multicast setup is made up of a management entity (PC or vDisplay) configuring a GigE Vision
transmitter to send block data to a multicast group granted by an IGMP Ethernet switch. GigE Vision
receivers may then connect to the multicast group and receive the blocks.
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eBUS SDK Programmer’s Guide
On Controller (master) PC
1. Connect to the IP engine using PvDevice::Connect().
2. Set the streaming destination to the multicast groups IP and port.
3. Lock device parameters.
4. Execute the AcquisitionStart command from the device’s GenICam interface.
The application receiver (slave) should receive images from the GigE device transmitter.
5. Execute the AcquisitionStop command from the devices GenICam interface.
6. Unlock the devices parameters.
7. Cleanup.
Code Example
C++
//**************************************************************************//
// Step 1: Set the Communication parameters before connecting //
//**************************************************************************//
// For an example for setting DefaultHeartTimeout, see the
// "Access Communication Settings" section //
**************************************************************************//
// Step 2: Connect to device
//**************************************************************************//
PvDevice lDevice;
// method 1: Connect using the device info lDeviceInfo obtained in the
// "Detect and Select Device" section
lDevice.Connect(lDeviceInfo, aAccessType );
// method 2: Connect using the IP Engine's IP address; in this example it is
// "192.168.1.128"
lDevice.Connect("192.168.1.128", aAccessType );
// method 3: Connect using IP Engine's MAC address; in this example it is
// “00:11:1C::00:76:0A” The format “00-11-1C-00-76-0A also works.
lDevice.Connect("00:11:1C:00:76:0A", aAccessType );
//**************************************************************************//
// Step 3: Set up the stream packet size. Only the device controller can do
// this. If you skip this step, the current value of GevSCPPacketSize on
// the device is used.
//**************************************************************************//
// Option A: Perform auto negotiation to find largest packet size that can be
// used on the network link. At the completion of this call, GevSCPPacketSize
// is set to the largest possible packet size; if NegotiatePacketSize() fails,
// it is set to 1476 lDevice.NegotiatePacketSize( 0, 1476 );
// Option B: Set a value that you know works well. In the case of multicasting
// or remote unicast, this is good practice, as auto negotiation does not test
// all stream receivers to determine the largest packet size that can be used
lDevice.GetGenParameters()->SetIntegerValue( "GevSCPSPacketSize",1476 );
//**************************************************************************//
// Step 4: Set up proper streaming networking topology
//**************************************************************************//
// Scenario 4: Multicast master -- this application controls the device.
lDevice.SetStreamDestination( "239.192.1.1" , 1042 );
// In case this application also receives image data it opens the stream
// otherwise it does not need to create a stream object
lStream.Open(lDeviceInfo ->GetIPAddress(), "239.192.1.1" , 1042)
Application Development
43
Sample Code
• To view sample code for PvMulticastMaster, view the PvMulticastMasterSample file. For
information about accessing the sample code, see “Accessing the Sample Applications” on page
15.
On streaming (slave) PCs
1. Open PvStream to listen for devices on the same multicast groups IP and port.
2. Create and start a PvPipeline.
3. Retrieve PvBuffer pointers from PvPipeline, and re-queue the pointer when done.
It is important to do re-queue the pointer, otherwise there will not be enough buffers in the
PvPipeline.
4. Disconnect from the GigE Vision device using PvDevice::Disconnect.
Code Example
C++
//**************************************************************************//
// Step 1: Set the Communication parameters before connecting
//
//**************************************************************************//
// For an example for setting DefaultHeartTimeout, see the
// "Access Communication Settings" section
//**************************************************************************//
// Step 2: Connect to device
//**************************************************************************//
PvDevice lDevice;
// method 1: Connect using the device info lDeviceInfo obtained in the
// "Detect and Select Device" section
lDevice.Connect(lDeviceInfo, aAccessType );
// method 2: Connect using the IP Engine's IP address; in this example it is
// "192.168.1.128"
lDevice.Connect("192.168.1.128", aAccessType );
// method 3: Connect using IP Engine's MAC address; in this example it is
// “00:11:1C::00:76:0A” The format “00-11-1C-00-76-0A also works.
lDevice.Connect("00:11:1C:00:76:0A", aAccessType );
//**************************************************************************//
// Step 3: Set up the stream packet size. Only the device controller can do
// this. If you skip this step, the current value of GevSCPPacketSize on
// the device is used.
//**************************************************************************//
// Option A: Perform auto negotiation to find largest packet size that can be
// used on the network link. At the completion of this call, GevSCPPacketSize
// is set to the largest possible packet size; if NegotiatePacketSize() fails,
// it is set to 1476 lDevice.NegotiatePacketSize( 0, 1476 );
// Option B: Set a value that you know works well. In the case of multicasting
// or remote unicast, this is good practice, as auto negotiation does not test
// all stream receivers to determine the largest packet size that can be used
lDevice.GetGenParameters()->SetIntegerValue( "GevSCPSPacketSize",1476 );
//**************************************************************************//
// Step 4: Set up proper streaming networking topology
//**************************************************************************//
// Scenario 5: Multicast slave -- this application does not control the device
// and only receives image data. This application does not need to connect to
// the device, but still needs to know the device's IP Address
lStream.Open(lDeviceInfo ->GetIPAddress(), "239.192.1.1" , 1042)
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eBUS SDK Programmer’s Guide
Sample Code
• To view sample code for PvMulticastSlave, view the PvMulticastSlaveSample file. For
information about accessing the sample code, see “Accessing the Sample Applications” on page
15.
Using a GigE Vision Transmitter to Send GigE Vision Data
The eBUS SDK provides the capability to send GigE Vision data to GigE Vision receivers, using the
Video Server API. The Video Server API is a component of the eBUS SDK that transmits video over the
network from a computer to one or more alternate destinations, in a GigE Vision® compliant manner.
The Video Server API does not currently support the GigE Vision packet resend capability.
To configure a GigE Vision transmitter to send GigE Vision data
1. Create a PvBuffer pool.
Note: You can use the eBUS SDK to allocate the memory for a buffer, or you can attach buffers to
an existing memory pool (allocated by another method). If you are using an existing memory pool,
you can use PvBuffer::Attach(). For more information, see PvBuffer::Attach() in the eBUS SDK
API Help File.
2. Optionally, initialize the transmitter with the PvBuffer pool just created by calling
PvTransmitterRaw::LoadBufferPool().
3. Create an instance of PvTransmitterRaw.
4. Bind the PvBuffer pool to the PvTransmitter.
Note: LoadBufferPool() is an optional method that provides the transmitter with a set of buffers
that can be retrieved immediately by calling RetrieveFreeBuffer().
5. Optionally create a PvVirtualDevice instance so the application can respond to discovery requests
by the receivers.
• Call PvVirtualDevice::StartListening() to listen on a specific network interface.
Note: Only one PvVirtualDevice() instance can exist on a NIC, however multiple
PvTransmitterRaw() instances can exist on a NIC. The number of PvTransmitterRaw()
instances is based on the amount of network bandwidth that is available.
6. Use PvTransmitterRaw::Open() to open a connection to the destination GigE Vision receiver.
7. Call PvTransmitter::ResetStats() to reset the transmitter statistics.
8. Call PvTransmitter::SetMaxPayloadThroughput() to set the desired effective throughput.
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45
9. In a loop:
• Call PvTransmitterRaw::RetrieveBuffer() to retrieve a free buffer from the list of available
buffers.
• Copy the data to the newly retrieved buffer.
• Call PvTransmitterRaw::QueueBuffer() to queue the buffer to the transmitter.
Note: PvTransmitterRaw::QueueBuffer() is an asynchronous method call (with its own thread)
that can potentially return before the PvBuffer is sent out of the system.
Do not access the PvBuffer after it is queued to the transmitter (because the SDK no longer owns the
buffer). Doing so may result in corrupt data.
If you are not using the buffer pool, you can use PvBuffer.GetOperationalResult() to determine if the buffer
was sent out properly.
10. To gracefully stop transmission.
• Call PvTransmitterRaw::AbortQueuedBuffer() to abort transmission of currently queued
PvBuffers.
• In a loop call PvTransmitterRaw::RetrieveFreeBuffer and delete all reclaimed PvBuffers.
• Call PvVirtualDevice::StopListening() to stop the device from listening.
• Call PvTransmitter::Close() to close the transmitter instance.
Code Example
C++
// Allocate transmit buffers
PvBufferList lBuffers;
PvBufferList lFreeBuffers;
for ( PvUInt32 i = 0; i < lConfig.GetBufferCount(); i++ )
{
// Alloc new buffer
PvBuffer *lBuffer = new PvBuffer();
lBuffer->GetImage()->Alloc( lWidth, lHeight, lPixelFormat );
// Set to 0
memset( lBuffer->GetDataPointer(), 0x00, lSize );
// Add to both buffer list and free buffer list
lBuffers.push_back( lBuffer );
lFreeBuffers.push_back( lBuffer );
}
// Create transmitter, set packet size
PvTransmitterRaw lTransmitter;
lTransmitter.SetPacketSize( lConfig.GetPacketSize() );
Continued on next page...
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eBUS SDK Programmer’s Guide
// Create virtual device (used for discovery)
PvVirtualDevice lDevice;
lDevice.StartListening( lConfig.GetSourceAddress() );
cout << "Listening for device discovery requests on " << lConfig.GetSourceAddress() << endl;
// Open transmitter - sets destination and source
PvResult lResult = lTransmitter.Open(
lConfig.GetDestinationAddress(), lConfig.GetDestinationPort(),
lConfig.GetSourceAddress(), lConfig.GetSourcePort() );
if ( !lResult.IsOK() )
{
cout << "Failed to open a connection to the transmitter." << endl;
return 1;
}
// Used to transmit at a steady frame rate
PvFPSStabilizer lStabilizer;
// Acquisition/transmission loop
while(IsTransmitting)
{
// Step 1: Copy image data to a free buffer
// Are there buffers available for transmission?
if ( lFreeBuffers.size() > 0 )
{
// Retrieve buffer from list
PvBuffer *lBuffer = lFreeBuffers.front();
lFreeBuffers.pop_front();
// Copy the image to the free buffer, user defined CopyToPvBuffer method
CopyToPvBuffer( lBuffer );
// Queue the buffer for transmission
lTransmitter.QueueBuffer( lBuffer );
}
// Step 2: Retrieve free buffer(s) and add to free buffer pool
PvBuffer *lBuffer = NULL;
while ( lTransmitter.RetrieveFreeBuffer( &lBuffer, 0 ).IsOK() )
{
// Queue buffers back in available buffer list
lFreeBuffers.push_back( lBuffer );
}
}
// Close transmitter (will also abort buffers)
lTransmitter.Close();
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47
Advanced SDK Functionality
The following section provides you with steps to configure advanced SDK functionality.
Using the PvAcquisitionStateManager to Control the Image Stream and Lock the
GenICam Node Map
The PvAcquisitionStateManager class controls the starting and stopping of the stream, and locks the
GenICam node map features while video is streaming. For detailed information about how the
PvAcquisitionStateManager class works with the AcquisitionStart, AcquisitionStop, and
TLParamsLocked GenICam features, see the eBUS SDK API Help File.
To use the PvAcquisitionStateManager to control the image stream and lock the
GenICam node map
1. The container class declaration (in this case PvSimpleUISampleDlg) needs to inherit from
PvAcquisitionStateEventSink.
2. The container class implementation (in the code example we are using PvSimpleUISampleDlg):
•
•
•
•
Creates the acquisition state manager.
Registers the callback.
Implements the callback.
Acts upon the state change.
Code Example
C++
class PvSimpleUISampleDlg : public CDialog, PvGenEventSink, PvAcquisitionStateEventSink
{
:
:
// PvAcquisitionStateEventSink implementation
void OnAcquisitionStateChanged( PvDevice* aDevice, PvStreamBase* aStream, PvUInt32
aSource, PvAcquisitionState aState );
:
:
PvAcquisitionStateManager *mAcquisitionStateManager;
:
:
}
// Create acquisition state manager
mAcquisitionStateManager = new PvAcquisitionStateManager( &mDevice, &mStream );
// Register callback
mAcquisitionStateManager->RegisterEventSink( this );
// Callback implementation
void PvSimpleUISampleDlg::OnAcquisitionStateChanged( PvDevice* aDevice, PvStreamBase* aStream,
PvUInt32 aSource, PvAcquisitionState aState )
{
// Add some code to act upon the state change.
}
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eBUS SDK Programmer’s Guide
Using the PvFPSStabilizer Class to Specify the Frame Rate that is Displayed
The PvFPSStabilizer class allows you to display video at a desired frame rate, even though the frame rate
of the video received by the SDK may be faster, or be subject to jitter. This class is not part of the core of
the eBUS SDK. It is provided as a utility class shared by some Pleora samples.
To use this class, instantiate an object and call the IsTimeToDisplay() method each time a new buffer is
received and specify the desired frame rate.
This class does not directly influence the behavior of the display. It assumes that a frame was displayed
each time IsTimeToDisplay() returns true. IsTimeToDisplay() returns true when — dependent on the
specified frame rate target and the previous times IsTimeToDisplay() returned true — it is time to display
a frame.
To use the PvFPSStablizer class to specify the frame rate that is displayed
1. Start acquisition.
2. Reset the history using the Reset() method of the PvFPSStablizer class.
3. When a new buffer is received, call the IsTimeToDisplay() method to determine if
PvDisplayWnd::Display should be called.
The IsTimeToDisplay() method is used to determine if displaying a frame now would bring the
stream closer to the desired display frame rate (the aTargetFPS property).
If the IsTimeToDisplay() method returns true, call PvDisplayWnd::Display.
Code Example
C++
if ( mStabilizer.IsTimeToDisplay( mTargetFPS ) )
mDisplayWnd->Display( *aBuffer, mVSync );
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49
Persisting Configuration Settings
PvConfigurationWriter and PvConfigurationReader let you save and load settings and state
information. You can save:
• The state of the GigE Vision device and stream states, for example, all parameters.
• Your own custom strings.
To save your state information
1. Create a configuration writer, using PvConfigurationWriter constructor.
2. Store the state information in the configuration writer.
• For GigE Vision device settings (PvDevice objects), using Store(PvDevice,PvString).
• For stream settings (PvStream objects), using Store(PvStream,PvString).
3. Optionally, store your own state information, using Store(PvString,PvString).
4. Save the stored information to disk, using Save().
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eBUS SDK Programmer’s Guide
To load your GigE Vision device settings (PvDevice object) or stream receiver (PvStream
object) state from disk
1. Create a configuration reader using PvConfigurationReader.
2. Load the file from disk, using Load().
3. Retrieve all devices/streams or access them by name, that is:
• Get the number of configurations by using the following methods:
• GetDeviceCount()
• GetStreamCount()
• GetStringCount()
You can either retrieve all devices/streams or access them by name, if you know which name to look for. It
depends what the application needs.
• Get the name of a configuration by using the following methods:
• GetDeviceName()
• GetStreamName()
• GetStringName()
4. Apply a configuration to an object by using the following methods:
• Restore(PvUInt32,PvDevice*)
• Restore(PvUInt32,PvStream &)
• Restore(PvUInt32,PvString &)
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51
Code Example
C++
PvDevice lDevice;
PvStream lStream;
// Connect and detect to device and stream
…
//**************************************************************************//
//
Save all settings into the persistent file (XML format) on PC
//
//**************************************************************************//
PvConfigurationWriter lWriter;
lWriter.Store( &lDevice, "MyDevice" );
lWriter.Store( &lStream, "MyStream" );
lWriter.Store( "Some custom string content", "MyString" );
// Optional save a custom string
lWriter.Save( "MyConfigFile.pvcfg" );
//*************************************************************************//
//
Load the persistent file and apply the settings
//
//*************************************************************************//
PvConfigurationReader lReader;
lReader.Load( "MyConfigFile.pvcfg" );
lReader.Restore( "MyDevice", &lDevice );
lReader.Restore( "MyStream", lStream );
// Load custom string from configuration file
PvString lString;
lReader.Restore( lString, "MyString" );
• Communication settings are saved and loaded at the same time the device's settings are saved and loaded.
• Devices are identified by their MAC addresses in the device and stream configuration containers. Their IP
addresses are not saved.
• If the PvDevice object used in the restore operation is already connected or opened, only the device control
settings are applied (the SDK does not disconnect and reconnect to the original device). If the PvDevice object is
not connected, the configuration reader object tries to find the original device on the network and connects to it
before restoring the device's control settings.
• If the PvStream object used in the restore operation is already opened, only the stream's control parameters are
applied. If the PvStream object is not opened, the configuration reader object tries to open the PvDevice object
before restoring the stream's control parameters.
• It is possible to save more than one device, stream and/or string in a single configuration file. Individual device/
stream/string instances can either be referred to by index or name.
• As the container supports more than one device/stream/string, they can be retrieved based on their position in
the container or they can be named.
Sample Code
• To view sample code for PvConfigurationReader, view the PvConfigurationReaderSample file
located at C:\Program Files (x86)\Pleora Technologies Inc\eBUS SDK\Samples.
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eBUS SDK Programmer’s Guide
Link Status and Device Recovery
The following section describes how the eBUS SDK manages its connection with devices.
eBUS SDK Connection Lost and Recovery Mechanism
The eBUS SDK keeps the link with the device alive by sending heartbeat packets. When the device does
not receive a heartbeat, the connection is declared lost and the recovery process starts.
The eBUS SDK provides a very flexible recovery mechanism. It is based on callbacks to notify the
application of connection status changes so that the application can take appropriate action.
Device Recovery
Device Callbacks are achieved by implementing methods from the PvDeviceEventSink class. After
connecting a PvDevice, use the RegisterEventSink() method to register the callback PvDeviceEventSink
instance.
Table 6: Device Recovery Callbacks
Notification
Description
OnLinkDisconnected
Notification that the connection to the device has been lost. This happens when the
heartbeat thread of PvDevice fails to read the CCP register of the device.
This notification is sent to the application even if automatic device recovery is
disabled.
OnLinkReconnected
Notification that the connection to the device has been automatically restored. The
notification states that device control was regained; The notification does not specify
whether the cable was unplugged, or that the device was power cycled, for example.
This notification is only received if the connection was restored. Connection is only
automatically restored if device recovery is enabled.
To enable automatic device recovery, set the LinkRecoveryEnabled GenICam Boolean of
PvDevice::GetGenLink() to True. It is set to False by default.
If device recovery is enabled, you receive the following notifications when a device is disconnected, and
then reconnected:
• OnLinkDisconnected. The device connection has been lost.
• OnLinkReconnected. The device has been reconnected.
If recovery is disabled and the connection to the device is lost, you receive only an OnLinkDisconnected
event.
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53
PC to Device Communication Link Settings
Some communication settings, described in the following table, are available in order to modify the
behavior of the communication link.
Table 7: Communication Settings
Communication
setting
Description
HeartbeatTimeout
The application, for example GEVPlayer, sends periodic heartbeats to the GigE Vision
device. The length of time between heartbeats is based on the HeartbeatInterval value
set. If the device does not send an acknowledgement before the heartbeat expires,
then the link between the application and the device is deemed to be disconnected.
HeartbeatInterval
Time in milliseconds between each heartbeat sent to the GigE Vision device.
MCTT
The amount of time (in milliseconds) that the GigE Vision device must wait before either
timing out or receiving acknowledgment for a message (interrupt).
MCRC
The number of retransmissions allowed when the GigE Vision device times out waiting
for acknowledgement of a message (interrupt).
AnswerTimeout
The amount of time the GigE Vision Device can take to respond to a command from the
application.
CommandRetryCount
The number of times a command is attempted before it is considered to be a failed
command.
LinkRecoveryEnabled
Used to attempt to automatically reconnect to a device when the connection is lost.
GEVPlayer’s Communication Control window is a good place to get familiar with all the features and
their descriptions.
The communication parameters are accessed through PvDevice::GetGenLink() (not
PvDevice::GetGenParameters(), which is for device control parameter access).
The following communication parameters are available either before or after the device connects.
Table 8: Communication Parameters
54
Communication parameters
Available
Description
DefaultHeartbeatTimeout
At connection
At connection, the DefaultHeartbeatTimeout value is
used to set the devices GevHeartbeatTimeout.
GevHeartbeatTimeout
After connection
If you would like to change the heartbeat timeout after
connecting to the device, change the
GevHeartbeatTimeout.
DefaultMCTT
At connection
At connection, the DefaultMCTT value is used to set
the device’s GevMCTT.
GevMCTT
After connection
If you would like to change the messaging timeout
value after connecting to the device, change the
GevMCTT.
eBUS SDK Programmer’s Guide
Table 8: Communication Parameters
Communication parameters
Available
Description
DefaultMCRC
At connection
At connection, the DefaultMCRC value is used to set
the device’s GevMCRC.
GevMCRC
After connection
If you would like to change the count retransmissions
after connecting to the device, change the GevMCRC.
AutoNegotiation and DefaultPacketSize are not automatically used at connection time. The application
needs to call PvDevice::NegotiatePacketSize() to let the eBUS SDK negotiate the maximum packet size
or set the device feature GevSCPSPacketSize as the DefaultPacketSize.
The AnswerTimeout, CommandRetryCount, HeartbeatInterval and LinkRecoveryEnabled parameters
can be changed before and after connecting to the device.
You may also override the command and messaging ports as shown below.
Table 9: Command and Messaging Ports — Before and After Connection
Before connection
After connection
When ForcedCommandPortEnabled is set to True,
ForcedCommandPort can be set
CommandPort is set to the value of
ForcedCommandPort
When ForcedMessagingPortEnabled is set to True,
ForcedMessagingPort can be set
MessagingPort is set to the value of
ForcedMessagingPort
Event Sinks
PvSystemEventSink: Auto-find Controller
PvSystemEventSink contains a callback that lets you define what happens when a PvSystem object finds
a GigE Vision device. The actual behavior is for you to define, but you could use this class to:
• Automatically filter GigE Vision devices that you (programmatically) determine are inappropriate.
• Begin displaying available GigE Vision devices before the search timeout expires, in the same way
that PvDeviceFinderWnd does, for example.
To comply with the auto-find controller (PvSystemEventSink object) interface
1. Create a class (MySink) that inherits from PvSystemEventSink (you can also extend an existing
class).
2. Declare the OnDeviceFound() method.
3. Define the code for the OnDeviceFound() method.
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To use the auto-find controller (PvSystemEventSink object)
1. Create an instance of your sink class using MySink (for example).
2. Find GigE Vision devices as you normally would (see PvSystem in the eBUS SDK API Help File),
but before using PvSystem::Find(), register your MySink class using
PvSystem::RegisterEventSink().
3. Once you’re done finding GigE Vision devices, unregister the event sink, using
PvSystem::UnregisterEventSink().
Code Example
C++
class MySink: public PvSystemEventSink
{
virtual void MySink::OnDeviceFound(
PvInterface *aInterface, PvDeviceInfo *aDeviceInfo,
bool &aIgnore );
};
void MySink::OnDeviceFound(
PvInterface *aInterface, PvDeviceInfo *lDeviceInfo,
bool &aIgnore )
{
if( lDeviceInfo != NULL )
{
//Handle the device found accordingly
//…
}
}
int deviceFind()
{
MySink mySink;
PvSystem aSystem;
aSystem.RegisterEventSink(&mySink);
PvResult lResult;
PvDeviceInfo *lDeviceInfo = 0;
// Find all GigE Vision devices on the network.
aSystem.SetDetectionTimeout( 100 );
lResult = aSystem.Find();
if( !lResult.IsOK() )
{
printf( "PvSystem::Find Error: %s", lResult.GetCodeString() );
return -1;
}
return 0;
}
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eBUS SDK Programmer’s Guide
Parameter callbacks - PvGenEventSink
To create a callback that runs when the feature's value changes:
1. Get the feature through the following steps:
• Use PvGenParameterArray::Get() to get specific feature object.
• Get the feature’s type using PvGenParameter::GetType().
• Optionally:
• Get/Set the feature’s value. Use the GetValue/SetValue method for the feature’s type (for
example, PvGenInteger::GetValue(), PvGenFloat::SetValue(), etc.)
• If the feature is a command, activate it using PvGenCommand::Execute().
2. Create a subclass of PvGenEventSink.
3. In your new class, override PvGenEventSink::OnParameterUpdate().
To use PvGenEventSink, PvGenParameter instances must register to the event sink using
PvGenParameter::RegisterEventSink().
Sample Code
• To view sample code for PvGenEventSink, view the GEVPlayerSample file located at
C:\Program Files (x86)\Pleora Technologies Inc\eBUS SDK\Samples.
Force GigE Device IP address
Use PvDevice::SetIPConfiguration() method when you wish to change the GigE Vision device’s IP
address. This is especially necessary when the device and the NIC are not on the same subnet.
As PvDevice::SetIPConfiguration() method is performed through a broadcast command, it works on
devices that are not reachable because of their IP configuration, but are on the same physical network.
The gateway parameter is optional and set by default to “0.0.0.0”.
You do not need to detect and select the device to set its IP address.
Code Example
C++
// Change the IP configuration of a device
PvDevice::SetIPConfiguration(
"00-11-22-33-44-55", // Device MAC address
"192.168.138.62", // New IP address of the device
"255.255.255.0", // New subnet mask of the device
"192.168.138.1" ); // New gateway of the device
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57
Serial Device Control
The GigE Vision device is connected to a camera head and may also be connected to other peripherals.
The eBUS SDK provides the following API classes which allow you to perform serial communication
with the camera head or other peripherals.
• PvSerialPortIPEngine
• PvIPEngineI2CBus for an I2C addressable peripheral
• PvSerialBridge
PvSerialPortIPEngine
Provides access to the serial ports on a GigE Vision device.
PvSerialPortIPEngine allows you to perform serial communications through Pleora’s GigE Vision
devices. PvSerialPortIPEngine is not supported by non-Pleora devices.
In some cases, use of the PvSerialPortIPEngine class to directly access the camera head interferes with the
synchronization between the GigE Vision device and the camera head. As an example, the SB-Pro IP
engine uses the serial port to communicate with the camera head of a Sony Block camera. If you use
PvSerialPortIPEngine at the same time, you may interfere with the communication exchanges.
To use a serial port
1. Connect to a device using any of the PvDevice::Connect() methods.
2. Open a serial port to the device using PvSerialPortIPEngine::Open().
3. Write to the serial port using PvSerialPortIPEngine::Write().
4. Read from the serial port using PvSerialPortIPEngine::Read().
5. Finally close the serial port using PvSerialPortIPEngine::Close().
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eBUS SDK Programmer’s Guide
To check if a GigE Vision device supports a specific serial port
1. Connect to a device using any of the PvDevice::Connect methods.
2. Use the PvSerialPortIPEngine::IsSupported() static method.
Code Example
C++
// Get device parameters need to control streaming
PvGenParameterArray *lParams = lDevice.GetGenParameters();
// Configure serial port - this is done directly on the device GenICam interface,
not on the serial port object! We use Uart0, 9600 N81
lParams->SetEnumValue( "Uart0BaudRate", "Baud9600" );
lParams->SetEnumValue( "Uart0NumOfStopBits", "One" );
lParams->SetEnumValue( "Uart0Parity", "None" );
// For this test to work without attached serial hardware we enable the port
loopback
lParams->SetBooleanValue( "Uart0Loopback", true );
// Open serial port
PvSerialPortIPEngine lPort;
PvResult lResult = lPort.Open( &lDevice, PvIPEngineSerial0 );
if ( !lResult.IsOK() )
{
printf( "Unable to open serial port on device: %s %s\n",
lResult.GetCodeString().GetAscii(), lResult.GetDescription().GetAscii() );
return false;
}
printf( "Serial port opened\n" );
// Make sure the PvSerialPortIPEngine receive queue is big enough
lPort.SetRxBufferSize( 2 << TEST_COUNT );
PvUInt32 lSize = 1;
for ( int lCount = 0; lCount < TEST_COUNT; lCount++ )
{
// Allocate test buffers
unsigned char *lInBuffer = new unsigned char[ lSize ];
unsigned char *lOutBuffer = new unsigned char[ lSize ];
// Fill input buffer with random data
for ( PvUInt32 i = 0; i < lSize; i++ )
{
lInBuffer[ i ] = ::rand() % 256;
}
// Send the buffer content on the serial port
PvUInt32 lBytesWritten = 0;
lResult = lPort.Write( lInBuffer, lSize, lBytesWritten );
if ( !lResult.IsOK() )
{
// Unable to send data over serial port!
printf( "Error sending data over the serial port: %s %s\n",
lResult.GetCodeString().GetAscii(),
lResult.GetDescription().GetAscii() );
return false;
}
printf( "Sent %i bytes through the serial port\n", lBytesWritten );
Continued on next page...
Application Development
59
//
//
//
//
//
Wait until we have all the bytes or we timeout. The Read method only
times out if not data is available when the function call occurs,
otherwise it returns all the currently available data. It is possible
we have to call Read multiple times to retrieve all the data if all the
expected data hasn't been received yet.
// Your own code driving a serial protocol should check for a message
// being complete, whether it is on some sort of EOF or length. You should
// pump out data until you have what you are waiting for or reach some
//timeout.
PvUInt32 lTotalBytesRead = 0;
while ( lTotalBytesRead < lSize )
{
PvUInt32 lBytesRead = 0;
lResult = lPort.Read( lOutBuffer + lTotalBytesRead, lSize - lTotalBytesRead,
lBytesRead, 100 );
if ( lResult.GetCode() == PvResult::Code::TIMEOUT )
{
printf( "Timeout\n" );
break;
}
// Increment read head
lTotalBytesRead += lBytesRead;
}
// Validate answer
if ( lTotalBytesRead != lBytesWritten )
{
// Did not receive all expected bytes
printf( "Only received %i out of %i bytes\n", lTotalBytesRead,
lBytesWritten );
}
else
{
// Compare input and output buffers
PvUInt32 lErrorCount = 0;
for ( PvUInt32 i = 0; i < lBytesWritten; i++ )
{
if ( lInBuffer[ i ] != lOutBuffer[ i ] )
{
lErrorCount++;
}
}
// Display error count
printf( "Error count: %i out of %i (%.3f%%)\n", lErrorCount, lBytesWritten,
(double)lErrorCount / (double)lBytesWritten * 100.0 );
}
// Free test buffers
delete []lInBuffer;
delete []lOutBuffer;
// Grow test case
lSize *= 2;
}
// Close serial port
lPort.Close();
printf( "Serial port closed\n" );
PvIPEngineI2CBus
Some Pleora cameras, sensors, or peripherals can be controlled using I2C. The PvIPEngineI2CBus class
is not supported by non-Pleora devices.
In this case, the PvIPEngineI2CBus lets you send commands to your camera and receive the camera’s
replies.
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eBUS SDK Programmer’s Guide
I2C uses the concept of a master and slave, where the master controls the clock and initiates reads and
writes. For PvIPEngineI2CBus, the GigE Vision device is the I2C master. The I2C slave is typically a
camera, but could be any I2C-capable device connected to the GigE Vision device.
The PvIPEngineI2CBus methods manage the GigE Vision device and camera communication required
to send a message to the camera and to read back replies. For example, the BurstWrite() method involves
the following transaction:
1. Your application calls BurstWrite().
2. The eBUS SDK passes the entire message to the GigE Vision device using Ethernet.
3. BurstWrite() blocks.
4. GigE Vision device to camera: [Start condition] aSlaveAddress [Write - SDA low]
5. Camera to GigE Vision device: Acknowledge
6. GigE Vision device to camera: [First 8 bits of aBuffer]
7. Camera to GigE Vision device: Acknowledge
8. GigE Vision device to camera: [Next 8 bits of aBuffer]
9. Camera to GigE Vision device: Acknowledge
...
10. GigE Vision device to camera: [Last 8 bits of aBuffer]
11. Camera to GigE Vision device: Acknowledge
12. GigE Vision device to camera: [Stop condition]
13. GigE Vision device reports the successful transmission of the message to the PC (via Ethernet).
14. BurstWrite() method unblocks (returns).
To send I2C-protocol serial commands to your camera
1. Create an I2C serial controller using PvIPEngineI2CBus.
2. Send a command to the camera using BurstWrite().
3. Test to ensure the message sent succeeded by checking the PvResult returned by BurstWrite().
4. Retrieve the camera’s reply using BurstRead().
5. Test to ensure the message retrieval succeeded by checking the PvResult returned by BurstRead().
6. Test the content of the message from the camera by using aBuffer and aBufferSize parameters and
your own code.
Sample Code
• To view sample code for PvI2CSample, view the PvI2CSample file located at C:\Program Files
(x86)\Pleora Technologies Inc\eBUS SDK\Samples.
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61
PvSerialBridge
Bridges a computer serial port or Camera Link DLL to an IP engine serial port.
This class is only available for the Windows operating system.
PvSerialBridge is bidirectional, it can either:
• Take data from a computer’s serial port or eBUS SDK Camera Link DLL (clserpte.dll) and send it
to an IP engine serial port.
• Or, take data from an IP engine’s serial port and send it a computer serial port or eBUS SDK
Camera Link DLL.
Depending on the Start method that is used, the bridge is either started as a serial bridge or Camera Link
DLL bridge.
Statistics can be retrieved about a bridge: count of transmitted and received bytes.
The serial port can be used with a stand-alone application, usually a camera configuration application
relying on a serial port (ie: COM1, COM2, etc.) to interact with the camera. The port selected by the
application must be connected with a NULL modem to the port used by the bridge. It can be two real
serial ports connected together or two virtual ports with a serial port emulation software/driver.
The Camera Link DLL can be used with a stand-alone application, usually a camera configuration
application, relying on the API described in the Camera Link standard used to interface a serial port.
Instead of being the serial port of a frame grabber here it is the serial port of a Pleora IP engine.
For more information, see the Establishing a Serial Bridge Application Note, available at the Pleora
Technologies Support Center.
Image Saving
PvBufferWriter lets you save image buffers (PvBuffer objects) to the disk. The image buffer can be saved
as a Windows Bitmap file (RGB 32) or in raw format, regardless of the original image pixel type.
The raw format has no header (width, height, pixel format, etc.) it just contains the raw image data as in the
PvBuffer/PvImage.
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eBUS SDK Programmer’s Guide
To save an image buffer to disk
1. Acquire an image.
For more information, see “To use PvStream to receive images” on page 33.
2. Create an instance of PvBufferWriter::PvBufferWriter().
3. Save the image to disk using Store().
Code Example
C++
PvBufferWriter lWriter;
// Save as WindowsBitmap
lWriter.Store( lBuffer, "image.bmp", PvBufferFormatBMP );
// Save as raw data
lWriter.Store( lBuffer, "image.raw", PvBufferFormatRaw );
Sample Code
• To view sample code for PvBufferWriterSample, view the PvBufferWriterSample file located at
C:\Program Files (x86)\Pleora Technologies Inc\eBUS SDK\Samples.
Pixel Format Conversion
The PvBufferConverter class converts an image buffer with one pixel type to another pixel type. With
the eBUS SDK, you simply use a PvBuffer- Converter to which you pass an input and output buffer. This
converts the pixel type from one of the defined GigE Vision pixel types to RGB. It automatically converts
the content of the input buffer to the output buffer, using the pixel type of the output buffer. You don’t
have to select a specific pixel converter; it is automatically managed for you.
The pixel converter does not perform tap reconstruction, nor Bayer pattern offset adjustment. Deinterlacing
is managed by the PvFilterDeinterlace class. Not all pixel type conversion are supported, use
IsConversionSupported().
Application Development
63
To change an image’s format
1. Acquire an image.
For more information, see “To use PvStream to receive images” on page 33.
2. Create an image-format converter (PvBufferConverter object) using
PvBufferConverter::PvBufferConverter().
3. Test to see if you can convert your image to your preferred pixel type using
IsConversionSupported().
For your source pixel type, use PvBuffer::GetPixelType(); for your destination, select an
enumeration from PvPixelType.h.
4. Create a destination buffer.
For more information, see the PvBuffer Class Reference topic in the eBUS SDK API Help File. (you
define the destination image’s pixel type during this step).
5. Optionally, configure options such as Bayer filtering, using SetBayerFilter().
6. Convert the image to the new pixel type using Convert().
Code Example
C++
//****************************************************************************//
//
Create converter object and a destination buffer of RGB32bit pixel format
//
//****************************************************************************//
PvBufferConverter lConverter;
PvBuffer lOutput;
lOutput.Alloc( lSizeX, lSizeY, PvPixelWinRGB32 );
lConverter.Convert( lBuffer, &lOutput );
Sample Code
• To view sample code for PvRGBFilter, view the PvRGBFilterSample file located at C:\Program
Files (x86)\Pleora Technologies Inc\eBUS SDK\Samples.
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eBUS SDK Programmer’s Guide
Window UI Components
The following list includes predefined display UI component classes that can be used to display and
interactively control the device’s attributes:
• PvDeviceFinderWnd: can be used to find all GigE Vision devices on a network and lets the user
select one.
• PvGenBrowserWnd: can be used to monitor and control GenICam features.
• PvDisplayWnd: can be used to display the contents of an image.
• PvTerminalIPEngineWnd: can be used to directly communicate from the PC to a serial based
component that is part of the GigE Vision device.
• PvSerialBridgeManagerWnd: A user interface for configuring PvSerialBridge instances of a
PvDevice.
Display Images - PvDisplayWnd
The PvDisplayWnd class is used to display a PvBuffer.
To display images
1. Decide if you want the display in a standalone window or embedded as an element of a window you
control.
2. Create a display control (PvDisplayWnd object).
3. Optionally set the window’s position by using SetPosition().
4. Optionally, set the background color using SetBackgroundColor().
5. Make the display controller appear.
• To embed the display in your own application (a window you control yourself), use Create().
• In Windows, the second parameter of PvDisplayWnd.Create() must have a unique
resource ID, i.e. it is not used by any other controls of the parent window.
• In Linux, it is required to pass a QWidget pointer to the first parameter of
PvDisplayWnd.Create(). You do not need any input for the second parameter.
• To open the display in a modal window, use ShowModal().
• To open the display in a modeless window, use ShowModeless().
Application Development
65
6. Make an image appear in the display area using Display().
7. Optionally, update the image (show a movie by displaying many images sequentially, for example)
using additional calls to Display().
8. Optionally move the window.
• For standalone windows use SetPosition().
• For embedded windows, move the parent window, then force the display control to update to its
new location using UpdateBounds().
9. Close the window using Close().
• The eBUS SDK does not provide zoom or pan functionality programmatically. However, it is possible for
the you to zoom and pan using your keyboard and mouse.
• It is not necessary to convert the buffer in order to display it. The PvDisplayWnd class takes in the raw
buffer and converts it to the native video adapter pixel format to display. It is the most efficient way of
displaying a buffer. The buffer conversion is performed by the display using the video adapter memory
as the destination. If you use your own converter, you have to convert to a memory buffer and then
have the display copy that buffer to the video adapter memory.
• If you need to apply a PvFilterRGB class to your image for display purposes, set the converter of the
PvDisplayWnd' class o use the PvFilterRGB object you have configured. Then, the PvDisplayWnd
class applies the filter automatically on every image being displayed.
• If the standalone display window is created by a Windows console application, call the
PvDisplayWnd::DoEvents() method from the main thread of a console application in a loop.
• See the GEVPlayerSample and PvSimpleUISample files for complete, working examples of how to
embed a display into your own dialog.
• In Linux the Qt library is used for eBUS SDK GUI functions including display. As of eBUS SDK 2.0, the
Qt display does not yet support zooming and panning.
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eBUS SDK Programmer’s Guide
Code Example
C++
//********************************************************************//
// Option 1: Display in the embedded window of application
//********************************************************************//
lDisplayWnd.Create( GetSafeHwnd(), 10000 );
lDisplayWnd.SetPosition( 20, 20, 400, 300 );
lDisplayWnd.SetPosition( ;
lResult =lDisplayWnd.SetBackgroundColor( 0x00, 0x00, 0x20);
//
// ***************************************************************************//
// Option 2: Display in a stand alone window //
// ************************************************************************** //
PvDisplayWnd lDisplay;
lDisplay.SetPosition( 0, 0, 640, 480 );
lDisplayWnd.SetBackgroundColor( 0x00, 0x00, 0x20);
lDisplayWnd.SetTitle("My Display");
lDisplay.ShowModeless();
// Setup the PvFilterRGB for PvDisplayWnd's converter (optional)
PvFilterRGB lFilterRGB;
PvBufferConverter &aConverter = lDisplayWnd.GetConverter();
aConverter.SetRGBFilter( lFilterRGB );
// Display a retrieved image
lDisplayWnd.Display( *lBuffer );
// To close the display window
lDisplayWnd.Close( );
Sample Code
• To view sample code for window UI components, see the GEVPlayerSample and the
PvSimpleUISample files. For information about accessing the sample code, see “Accessing the
Sample Applications” on page 15.
Application Development
67
Chapter 7
System Level Information
This section provides you with important information you need to know when configuring your system
to ensure efficient video data transmission.
The following topics are covered in this chapter:
• “Bandwidth Overhead Calculation” on page 70
• “List of UDP Ports on the GigE Vision Device” on page 72
• “Host-Side Port Control” on page 73
System Level Information
69
Bandwidth Overhead Calculation
This section provides you with information to assist you with calculating Ethernet bandwidth
requirements. To understand the overall bandwidth requirements, it is helpful to understand the contents
of a single Ethernet Frame.
Single Ethernet Frame Size
The following table shows you sizes of the components contained in an Ethernet frame transferred on an
Ethernet link or cable.
The open source network protocol analyzer software, Wireshark, is often used to capture Ethernet frame
information for debugging purposes. Information captured by Wireshark is shown below in blue.
Table 10: Ethernet Frame Information
Preamble
Start-offramedelimiter
7 octets of
10101010
1 octet of
10101011
MAC
destination
MAC
source
Ethertype
/length
6 octets
6 octets
2 octets
Payload
CRC32
46-1500/
9000 octets
4 octets
Minimum size: 64 bytes
Maximum size, small packets: 1518 bytes
Maximum size, jumbo packets: > 9018 bytes
Minimum size: 72 bytes
Maximum size, small packets: 1526 bytes
Maximum size, jumbo packets: 9026 bytes
The following table shows you the individual sizes of the GigE Vision Stream Protocol (GVSP) and Pleora
protocol UDP components.
Table 11: UDP Information
70
Items
Size (bytes)
IP header
20
UDP header
8
Protocol header
8 for GigE Vision Stream Protocol (GVSP)
User data payload
Could be data of image, leader, trailer, or dummy padding
Ethernet payload padding
Could be non-zero to ensure the Payload size is equal to or larger
than 46.
eBUS SDK Programmer’s Guide
Based on the information shown in the tables above, we know that the Ethernet frame size is the size of
the GVSP payload, plus 62 bytes.
• From the Wireshark frame information, shown in blue in the UDP Information table, the User Datagram
part of the image frame contains the Protocol header + User data payload + Ethernet payload padding.
• In eBUS SDK, the GevSCPSPacketSize is the payload size including IP header, UDP header, GVSP
header, and User data payload. For easy calculation, GevSCPSPacketSize = 36 bytes + User data
payload.
• In GigE Vision protocol, for each image frame, there is always one leader and trailer packet. The last
image data packet only contains image data and no padding. So the last image data packet could be
smaller than the rest of the full size image data packets.
Calculating Ethernet Bandwidth
This section provides an example of how to calculate the Ethernet bandwidth required to transfer images
that are 640 pixels x 480 pixels, in mono 8 format, at 200fps, along with the UDP overhead. In this
example, the image data payload size is set to 1440 bytes per packet which corresponds to:
GevSCPSPacketSize =36 bytes +1440 bytes =1476 bytes per packet
One image frame size is 640x480 =307200 bytes. (307200 bytes / (1440 bytes per packet)) = (213
packets) x (1440 bytes per packet) + 480 bytes means that for each image frame there are 213 full image
data packets and one partial image data packet. The Ethernet frame size is shown in the following table.
Table 12: Ethernet Frame Size
Ethernet frame size (bytes)
GigE Vision protocol
Leader
92
Payload packets
1502x213
Last payload packet
542
Trailer*
72
Total
320632
* There are 2 bytes of Ethernet Payload padding for the trailer.
System Level Information
71
Table 13: Data Rate and Bandwidth
Bytes/s
MB/s
Image data rate
(307200 bytes / frame) x
(200 frame / second) =
61440000 bytes /
second
58.59
Ethernet bandwidth
required for GigE Vision
protocol
(320632 bytes / frame) x
(200 frame / second) =
64126400 bytes /
second
61.16
Bandwidth over head
(%)
4.39
Note: Bandwidth
overhead decreases to
approximately 0.5% when
jumbo frames are used.
List of UDP Ports on the GigE Vision Device
The following table identifies ports available on Pleora GigE Vision devices.
Table 14: UDP Ports
Name in GEV protocol
Pleora device using GigE Vision protocol
GVCP
3956*
Message
4
Stream channel #0
20202. Note that this could be changed in future.
Stream channel #1
20203
* Port 3956 is for any GigE Vision device as define in the GigE Vision Specification.
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eBUS SDK Programmer’s Guide
Host-Side Port Control
When your GigE Vision compliant application, for example the Pleora sample application GEVPlayer,
connects to a GigE Vision device using the method PvDevice::Connect(), or when the application opens
a PvStream, the eBUS SDK uses, by default, any host-side UDP ports assigned by the operating system.
When the application takes control of the GigE Vision device, there are three host-side UDP ports the
application can control. They are the command link (used to send commands to the IP engine),
messaging channel (used to send messages from the IP engine to the application), and stream destination
UDP ports.
The command link and messaging channel host-side UDP port can be configured through the command
link parameters.
The stream destination port can be configured by passing the port number as the aDataPort of
PvStream::Open().
System Level Information
73
Chapter 8
Building and Distributing an eBUS SDK Application
To develop an application on a Windows-based operating system, please see Creating a new C/C++
project in the eBUS SDK API Help File.
To develop an application on Linux, please refer to the eBUS Linux Software Guide.
The environment variable $(PUREGEV_ROOT) can be used to reference the base directory location.
To distribute the application, refer to the Custom Install Guide.
eBUS Driver Installer API
This sample shows how to display or install eBUS drivers to the network adapters on a given computer
from your own application (through the eBUS driver installation API) instead of using the Driver
Installation Tool. The Driver Installation Tool is built around the same SDK. Some customers have been
developing their own Driver Installation Tool.
Building and Distributing an eBUS SDK Application
75
Chapter 9
Appendix A — eBUS SDK Primitives and Classes
This chapter provides you with descriptions of eBUS SDK primitives and classes, and provides the
following information in table format:
• “eBUS SDK Primitives” on page 77
• “eBUS SDK Classes” on page 78
Table 15: eBUS SDK Primitives
Primitive
Description
PvUInt8
Unsigned integer, 8 bits
PvInt8
Signed integer, 8 bits
PvUInt16
Unsigned integer, 16 bits
PvInt16
Signed integer, 16 bits
PvUInt32
Unsigned integer, 32 bits
PvInt32
Signed integer, 32 bits
PvUInt64
Unsigned integer, 64 bits
PvInt64
Signed integer, 64 bits
Appendix A — eBUS SDK Primitives and Classes
77
Table 16: eBUS SDK Classes
Class
Description
PvBuffer
Used to hold data received from the device through a PvStream. Can manage
its own internal memory buffer (Alloc/Free) or be attached to an external
memory buffer (Attach/Detach).
PvBufferConverter
Used for image buffer conversion from any GigE Vision pixel type to a pixel type
that can be displayed.
PvBufferWriter
Used to save image buffers to the hard drive. Supports saving raw data (as
contained in the buffer) and can also save to RGB32 bitmaps.
When saving to RGB32 bitmaps, on-the-fly pixel conversion is performed if
required.
PvConfigurationReader
Used to read pvcfg configuration files and restore saved PvDevice, PvStream,
PvString and raw PvGenParameterArray content.
A pvcfg configuration file contains XML data.
PvConfigurationWriter
Used to write pvcfg configuration files holding complete PvDevice, PvStream,
PvString and raw PvGenParameterArray state information.
A pvcfg configuration file contains XML data.
PvDevice
(Host-side representation of a
GigE Vision device)
Used to control a GigE Vision device. Use the Connect/Disconnect methods to
connect a PvDevice to your GigE Vision device. The GenICam interface of the
device can be retrieved using the GetGenParameter method. It returns a
PvGenParameter- Array pointer. This GenICam interface is built at runtime from
an XML file that is downloaded automatically from the device. The host-side
communication link parameters are also configured through a
PvGenParameterArray that can be retrieved using the GetGenLink method.
The register map of the device can be directly accessed using the
ReadRegister, WriteRegister, ReadMemory and WriteMemory methods,
although this is reserved for more advanced applications and requires
knowledge of the register map specific to each GigE Vision camera or device.
See PvDeviceEventSink (in the eBUS SDK API Help File) for information on
how to receive raw messaging channel events from the device.
PvDeviceEventSink
Provides an event sink interface. Classes that need to receive event
notifications should inherit PvDeviceEventSink, and should be registered
through PvDevice::RegisterEventSink() in order to receive PvDevice
notifications. Use these notifications to be informed of raw messaging channel
events or unexpected disconnection events.
PvDeviceFinderWnd
Used to display a modal dialog displaying all GigE Vision devices on the
network and prompting the user to select one.
(GUI component)
Displayed using ShowModal. Returns OK if the user selected a device and
dismissed the dialog using the OK button. The selected device can be retrieved
in the form a PvDeviceInfo pointer using GetSelectedDevice.
Available on both Qt and MFC versions of PvGUI library.
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eBUS SDK Programmer’s Guide
Table 16: eBUS SDK Classes (Continued)
Class
Description
PvDeviceInfo
Contains information about a device detected on the network.
Can be retrieved from either a PvInterface of PvDeviceFinderWnd.
Can be used to connect a PvDevice to a GigE Vision device through the
Connect method.
PvDisplayWnd
(GUI component)
Used to display the contents of an image buffer. Typically used as a standalone modeless window or embedded in a dialog.
Available in the PvGUI library as either a Qt-based (OpenGL accelerated) or
MFC-based (DirectX accelerated) control.
PvFilter
Used for image processing.
PvFilterDeinterlace
Used to de-interlace image buffer content. Can either work on a buffer
containing the Even and Odd fields or from a pair of buffers containing the
Even and then Odd fields.
PvFilterRGB
Used to apply a RGB independent gain and offset to any RGB buffer,
PvGenBoolean
Can be true or false. Inherits from PvGenParameter.
(IBoolean GenICam parameter)
Displayed in the GenICam browser as a combo box having true and false as
possible values.
PvGenBrowserWnd
Attach a PvGenParameterArray() using the SetGenParameterArray() method.
(GenICam browser GUI
component)
Available on Qt and MFC PvGUI versions of the PvGUI library.
PvGenCommand
Cannot be read or written, but can be triggered using the Execute() method.
Inherits from PvGenParameter.
(ICommand GenICam parameter)
Displayed in the GenICam browser as a button that can be activated.
PvGenEnum
(IEnumeration GenICam
parameter)
PvGenEnumEntry
Holds a group of possible values each having unique string and integer values.
Inherits from PvGenParameter.
Displayed in the GenICam browser as a combo box containing all the possible
enumeration entry strings.
Represented by both a unique string and integer value.
(One possible value of a
PvGenEnum)
PvGenEventSink
Interface you inherit one of your classes from in order to receive GenICam
parameter invalidation events.
In order to receive these notifications you need to register your class using the
RegisterEventSink() method of PvGenParameter().
PvGenFile (GenICam file model
implementation)
Allows the reading/writing of a file to a GenICam node map (typically the
device’s) as long as it follows the standard GenICam model.
PvGenFloat
Represents a floating point value. Inherits from PvGenParameter.
(IFloat GenICam parameter)
Displayed in the GenICam browser as a text edit with a spin button.
Appendix A — eBUS SDK Primitives and Classes
79
Table 16: eBUS SDK Classes (Continued)
Class
Description
PvGenInteger
Represents an integer value. Inherits from PvGenParameter.
(IInteger GenICam parameter)
Displayed in the GenICam browser as a text edit with a spin button.
PvGenParameter
Contains common properties like GetName() and GetDescription().
(Base class for all PvGen
specialized types)
PvGenParameterArray
(An eBUS SDK abstraction of a
GenApi node map)
Contains a group of parameters that can be referred to by name or index.
Provides helper methods that can be used to query and cast PvGen
parameters in the right type and get/set values on PvGen parameters using a
single line of code. Can be attached to a PvGenTreeBrowserWnd GUI object to
allow dynamic interaction with the content of the GenApi node map.
The main PvGenParameterArray objects in the eBUS SDK are:
• PvDevice::GetGenParameters() for the main device GenICam
interface, built from the GenICam XML downloaded from the
device
• PvDevice::GetGenLink() for the communication channel
parameters (host-side) of a PvDevice, built from a static GenICam
XML bundled in the PvDevice library
• PvStream::GetParameters() for the stream parameters and
statistics, built from a static GenICam XML bundled in the
PvStream library
PvGenRegister (IRegister
GenICam parameter)
Represents a contiguous section of a register map.
While the parameter can be visible in the GenICam browser, it is not possible
to interact with the content of a PvGenRegister.
PvGenString
(IString GenICam parameter —
represents a string.)
Displayed in the GenICam browser as a plain text edit control.
PvInterface
Represents one network interface card on the system.
(Component of device discovery)
PvSystem enumerates all network interface cards represented by PvInterface
objects.
PvInterface objects can in turn enumerate all GigE Vision devices accessible
through their related network interface cards as PvDeviceInfo objects.
PvIPEngineI2CBus
80
Used to control an I2C bus attached to an GigE Vision device.
eBUS SDK Programmer’s Guide
Table 16: eBUS SDK Classes (Continued)
Class
Description
PvPipeline
Provides buffer management and an acquisition thread on top of a PvStream
object.
Buffers are retrieved from the pipeline using RetrieveNextBuffer(). Once no
longer needed (processing completed) the buffers need to be returned to the
pipeline using ReleaseBuffer().
We recommend allocating the buffers to the device’s PayloadSize (GenICam
parameter) value when initiating streaming using the SetBufferSize() method.
By default 16 buffers are used by PvPipeline. Using more buffers reduces the
odds of dropping frames at the pipeline output but at the expense of using
more memory and increasing potential latency. Use SetBufferCount() to
change the number of buffers used by the pipeline.
Even though PvPipeline can be used in most applications, it is recommended
to use a PvStream directly if you are working at high frame rates or when you
need to customize the pipeline behavior.
PvResult
Class representing function return values.
PvSerialPort
Provides a unified interface for serial port transmit and receive operations that
does not change for different serial port implementations.
(Base class for
PvSerialPortIPEngine)
PvSerialPortIPEngine
Used to interact with the serial ports on Pleora-based GigE Vision devices.
Supports UART, as well as Bulk interfaces (which can be configured as either
UART or USRT). For Bulk interface mode over I2C, use PvIPEngineI2CBus
instead. The serial port is not configured through the PvSerialPortIPEngine
object. Use the PvDevice GenICam interface instead. IsSupported() can be
used to query if a device supports a specific serial interface. Open() is used to
open a serial port through a PvDevice. Write() and Read() are used to send and
receive data through the serial port.
PvStatistics
Streaming statistics interface of a PvStreamRaw object. A pointer to the
PvStreamRaw statistics can be retrieved using the GetStatistics() method.
When using PvStream, the statistics are only provided through the
PvStream::GetParameters().
PvStream
Stream object that can be configured and that can provide its statistics
through a GenICam interface. Use GetGenParameters() to retrieve the
GenICam interface. Unlike PvStreamRaw, PvStream requires GenApi to be
deployed in the system.
PvStreamBase
Base class of both PvStream (GenICam) and PvStreamRaw (pure C++)
streaming classes. Provides core capabilities like queuing and retrieving
buffers.
PvStreamRaw
Stream object that can be configured and is providing its statistics directly
through a C++ interface, bypassing the GenICam interface.
It is recommended to use PvStream instead whenever possible.
Appendix A — eBUS SDK Primitives and Classes
81
Table 16: eBUS SDK Classes (Continued)
Class
Description
PvString
String class used to push and retrieve strings in and out of the eBUS SDK. Its
main goal is to provide a unified interface for both multi-byte and unicode and
to prevent string type mismatches between an application and the eBUS SDK.
PvString is not meant as a complete string class for eBUS SDK users. It
provides only basic capabilities to achieve its eBUS SDK input and output
goals.
PvSystem
Represents the host system in the PvSystem, PvInterface, and PvDeviceInfo
device finder architecture. Use the Find() method to discover devices.
PvSystem enumerates each network interface card. Use GetInterfaceCount()
and GetInterface() to retrieve pointers to PvInterface objects. Use
GetDeviceCount() and GetDeviceInfo() on retrieved PvInterface pointers to get
discovered devices in the form of PvDeviceInfo pointers.
PvSystemEventSink
Used for device found callbacks.
To use it, inherit your class from PvSystemEventSink and override the
OnDeviceFound() method.
Your method is called immediately after a device is found, before
PvSystem::Find() completes.
It can be used to report devices before the discovery timeout is elapsed (like
PvDeviceFinderWnd does) but can also be used to filter out devices by setting
the aIgnore parameter of the callback to true.
PvTerminalIPEngineWnd
Used to interact with the serial port on a GigE Vision device GigE Vision device.
Consists of a pair of transmit and receive text controls that can be used to
interact live with a serial port.
It does not require a serial port on the PC; just a connected PvDevice. All
available serial ports on the PvDevice are displayed in a combo box that the
user can dynamically select.
PvTransmitterRaw
Class for transmitting blocks using the GigE Vision streaming protocol.
PvVirtualDevice
Virtual GigE Vision device.
Used to provide basic GigE Vision device capabilities such as device discovery.
Can complement the PvTransmitterRaw class by allowing you to open a data
receiver connection using PvStream or PvStreamRaw.
PvWnd
(Base class for all GUI
components)
Provides common methods to control the title, move, open and close dialogs
and controls.
Use ShowModal() to create a modal dialog. A modal dialog prevents the user
from interacting with the other windows and dialogs of the application. The
device finder as used by GEVPlayer is a modal dialog.
Use ShowModeless() to create a modeless dialog. A modeless dialog lets the
user interact with other dialogs and windows of the application. The GenICam
tree browser of GEVPlayer is a modeless dialog.
Use Create() to create the window as a child control of a specific window.
GEVPlayer creates its PvDisplayWnd in such a way, nesting it in its main dialog.
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eBUS SDK Programmer’s Guide
Chapter 10
Appendix B — Layered Representation of the eBUS
SDK
This section provides an overview of the eBUS SDK in the form of a table. Each SDK layer depends on
the layer below.
An application that only requires streaming data and that does not require GenICam functionality from
a device is really only required to use the PvStreamRaw library. In this case the application would need
Layers 1 to 3.
An application that needs to control and stream data from a GenICam capable GEV device typically uses
the core layers 1 to 6.
Layers 7 and 8 are helper libraries, which can be developed by the customer if they choose not to use the
ones supplied by the eBUS SDK.
Appendix B — Layered Representation of the eBUS SDK
83
Figure 1: Layered Representation of the eBUS SDK
84
eBUS SDK Programmer’s Guide
Chapter 11
Appendix C — log4cxx Facility
The eBUS SDK makes use of the log4cxx facility to log events.
The logcfg file can be used to control the event log’s destination and level.
For more information about log4cxx, go to http://logging.apache.org/log4cxx/index.html.
If you are using Windows, the file is located in C:\Program Files\Common
Files\Pleora\log4cxx\default.logcfg
If you are using Linux, the file is located in /opt/pleora/ebus_sdk/lib/log4cxx/default.logcfg
You can also use the $PT_LOG_CONFIG environment variable to force the specific path of the logcfg
file. To do this, modify the following line, in the Example.log file, by adding “R”:
log4j.rootLogger=info, stdout, R
RootLogger is the parent category of all log4cxx categories. It is also possible to control logging through
categories. Pleora provides all categories in the log4cxx configuration files, but they are commented out.
Removing the comment enables logging for specific categories.
You can configure the following logging levels:
• info
• warning
• error
• fatal
Commonly used destinations (appenders) include:
• R - RollingFileAppender
• stdout- ConsoleAppender
Appendix C — log4cxx Facility
85
The Rolling file appender (R) attributes can also be modified.
Other loggers can also be added.
log4j.appender.R.File=${APPDATA} /example.log
${APPDATA} is C:\Users\<user name>\AppData\Roaming on Windows 7 and C:\Documents and
Settings\<user name>\Application Data on Windows XP. Note that this folder is hidden by default in
Windows explorer. You can reveal this folder by changing your Windows settings to reveal hidden folders
and files.
• Ensure that your process has permissions to write to the directory you point to.
• In Linux, the home folder shortcut(~) is not supported.
• Enabling the log degrades the overall performance of the system and it should only be done for
debugging purposes. You should enable only the datapoints that are absolutely necessary for
debugging purposes.
• For Windows 7 and Vista, it may be necessary to open the configuration file as a member of the
Administrators group.
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eBUS SDK Programmer’s Guide
Chapter 12
Reference: C++ eBUS SDK and .NET SDK Comparison
This chapter outlines the differences between the C++ version of the eBUS SDK and the C# version.
The following topics are covered in this chapter:
• “Types” on page 88
• “Properties” on page 88
• “Enumeration Types” on page 89
• “Error Management” on page 89
• “Enumerators” on page 91
• “Collections” on page 91
• “Callbacks” on page 92
The eBUS SDK .NET API Help File provides detailed information about the .NET classes available in the
Chapter. The Help file is available from the Windows Start menu (All Programs > Pleora Technologies Inc.
> eBUS SDK > eBUS SDK .NET API).
Reference: C++ eBUS SDK and .NET SDK Comparison
87
Types
The eBUS SDK types used in C++ are replaced by native .NET types. For example, PvString (which is
used to input and output strings to/from the eBUS SDK) is replaced with a string.
Table 17: .NET Equivalent of eBUS SDK C++ Types
C++ type
Replaced by the following .NET
type
PvString
String
PvInt64
Int64
PvUInt64
UInt64
PvInt32
Int32
PvUInt32
UInt32
PvInt16
Int16
PvUInt16
UInt16
PvUInt8
UInt8
Properties
The Get and Set methods in C++ are replaced by properties in the .NET version of the eBUS SDK. A
property internally defines Get and Set methods but it is only accessed through its property name. This
is because Get and Set methods without properties are not commonly used in .NET.
Exceptions to this rule are the Get and Set methods that require additional parameters (for example,
accessing values in the GenICam node tree). Because these methods cannot be replaced with properties,
they remain the same as their C++ counterparts.
C++
PvSerialPort lPort;
PvUInt32 lSize = lPort.GetRxBufferSize();
lPort.SetRxBufferSize( lSize );
C#
PvSerialPort lPort = new PvSerialPort();
UInt32 lSize = lPort.RxBufferSize;
lPort.RxBufferSize = lSize;
88
eBUS SDK Programmer’s Guide
Enumeration Types
Typed native .NET enumerations (not to be confused with GenICam enumerations) are used to wrap
C++ enumerations. The same underlying C++ values are used when defining the .NET enumerations.
.NET enumerations are different from C++ enumerations in the following ways:
• They throw an exception when you attempt to set them to an unsupported integer value.
• They can be converted to strings and the strings can be parsed and turned into an enumeration
value.
• They can be enumerated in statements, such as foreach statements.
Error Management
The .NET version of the eBUS SDK uses exceptions for error management, whereas the C++ version uses
methods that return error codes. For example, the eBUS SDK uses a void return type and throws a
PvException object when an error occurs, whereas the C++ version returns a PvResult object.
A PvException object contains a Result property, which is the PvResult that the method would have
returned. The ToString and Description members of PvException are adapted to return a string-based
representation of the PvResult containing the error code and description.
The only exception to this rule is streaming methods that manage buffers in the PvStreamBase,
PvPipeline, and PvTransmitterRaw classes. For performance reasons try/catch and exception
management are not used to handle these errors. For these methods, there is no change from the C++
approach — these methods return a PvResult object.
C++ eBUS SDK methods that have a PvResult return value and take a reference to a parameter to return
the true return value, now simply return the return value (or are implemented as properties). A good
example is the GetValue method of the PvGenParameter class.
C++
PvInt64 lValue = 0;
PvResult lResult = lInteger.GetValue( lValue );
if (!lResult.IsOK())
{
// ...
}
C#
try
{
Int64 lValue = lInteger.Value;
}
catch (PvException lEx)
{
// ...
}
Reference: C++ eBUS SDK and .NET SDK Comparison
89
C++
PvResult lResult = lDevice.Connect( "192.168.138.164" );
if ( !lResult.IsOK() )
{
// ...
}
lResult = lStream.Open( "192.168.138.164" );
if ( !lResult.IsOK() )
{
// ...
}
lResult = lPipeline.Start();
if ( !lResult.IsOK() )
{
// ...
}
C#
try
{
lDevice.Connect( "192.168.138.164" );
lStream.Open( "192.168.138.164" );
lPipeline.Start();
}
catch (PvException lEx)
{
// ...
}
90
eBUS SDK Programmer’s Guide
Enumerators
Some eBUS SDK classes are containers for other objects that can be enumerated. .NET interfaces are
implemented for these classes to allow the program to go through all of the objects with a foreach
statement:
• The PvInterface class enumerates PvDeviceInfo objects.
• The PvSystem class enumerates PvInterface objects.
• The PvGenEnum class enumerates PvEnumEntry objects.
• The PvGenParameterArray enumerates PvGenParameter objects.
C# (Without an Enumerator)
UInt32 lCount = lArray.Count;
for (UInt32 i = 0; i < lCount; i++)
{
PvGenParameter lP =
lParameterArray.Get(i);
// …
}
C# (With an Enumerator)
foreach (PvGenParameter lP in lArray)
{
// ...
}
Collections
The C++ version of the eBUS SDK has collection classes such as PvStringList, PvPropertyList, and
PvParameterList. In .NET, native List templates are used instead, such as List<string>, List<PvProperty>,
and List<PvParameter>.
Reference: C++ eBUS SDK and .NET SDK Comparison
91
Callbacks
All C++ eBUS SDK callbacks or virtual methods used as callbacks are implemented in PvDotNet as .NET
events of typed delegates.
Registering to an event is done in .NET using the += operator next to an event. The IntelliSense® feature
of Visual Studio then automatically generates an event handler in the .NET code.
This rule ensures that the callback mechanism is as expected by .NET users. It also leverages the
automated code generation performed by Visual Studio to help developers quickly and effortlessly hook
up events to their own code.
C++
class MyClass : PvDeviceEventSink
{
void OnLinkDisconnected( PvDevice *aDevice )
{
// ...
}
}
MyClass lMyObject;
lDevice.RegisterEvenSink( &lMyObject );
// ...
lDevice.UnregisterEventSink( &lMyObject );
C#
private void Device_OnLinkDisconnected( PvDevice aDevice)
{
// ...
}
lDevice.OnLinkDisconnected += new OnLinkDisconnectedEvent(Device_OnLinkDisconnected);
// ...
lDevice.OnLinkDisconnected -= new OnLinkDisconnectedEvent(Device_OnLinkDisconnected);
92
eBUS SDK Programmer’s Guide
Chapter 13
Technical Support
At the Pleora Support Center, you can:
• Download the latest software.
• Log a support issue.
• View documentation for current and past releases.
• Browse for solutions to problems other customers have encountered.
• Get presentations and application notes.
• Get the latest news and information about our products.
• Decide which of Pleora’s products work best for you.
To visit the Pleora Support Center
• Go to www.pleora.com and click Support Center.
If you have not registered yet, you are prompted to register.
Accounts are usually validated within one business day.
If you have difficulty finding an existing solution in the knowledge base, post a question by clicking Log a
Case. Provide as many specific details about your system and the nature of the issue as possible.
Technical Support
93
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