Display Server in DIST Systems
WinCC OA VIDEO is basically DIST capable, i.e. allows access to video streams as well as the use of sequences and scenarios in WinCC OA panels (by means of VideoEWO). The access to video streams of a DIST system by means of vimacc DisplayServer (or vimacc Workstation) is not directly possible.
In the following you can find instructions of how to access video streams of a DIST system. This applies as of the software version 2.2.10.29 provided by Accellence.
Restrictions
Unique Camera Numbers
The procedure described below generates copies of camera data points from the DIST system in the respective video project to which the corresponding DisplayServer Workstation instances belong.
In order to maintain the uniqueness of the camera data points as well as the corresponding stream IDs in the vimacc system, it must be ensured during project planning that the camera numbers remain unique in the overall network.It is therefore important to ensure during configuration that each camera number in the connected system is only used in one of the video projects at a time, e.g. by means of number ranges.
Identical Plant Keys
As is generally the case for the DIST suitability of WinCC OA VIDEO, it must be ensured that identical plant keys are used in the different video projects (and the associated vimaccOA systems). If this is not the case, no video streams can be retrieved or decoded.
Status Information
Status information about the corresponding cameras or streams is not available in the DisplayServer video project or in vimacc itself. As a result, the cameras are displayed with a black camera in the vimacc workstation, for example (which corresponds to the symbol for "Streaming on demand").
CameraDP_Synchronizer.ctl
As described in the introduction, for the DIST functionality of the DisplayServer, the camera data points must be transferred from the DIST system to the corresponding video project.
For this purpose, the video subproject of the WinCC OA-version contains a script that continuously synchronizes the required stream information at runtime. The link parameters in the camera data points are automatically extended by the parameter adl=1 which instructs the VideoManager not to transfer the configuration to the vimacc configuration database, but to directly add corresponding stream entries to the ActiveDeviceList of the vimacc runtime environment (Config).
This makes the stream information available to the vimacc DisplayServers (and vimacc workstations) without requiring additional camera licenses for the DIST cameras in the video project.
Installation
For each connected DIST system (with video streams to be used), a CTRL manager must be created in the video project of the display servers with the script CameraDP_Synchronizer.ctl. Add also the name of the DIST system to the CTRL script.
For example, for the DIST system dist_2:
Synchronization
If the CTRL script was set up correctly and a DIST connection to the corresponding system exists (or is established), the camera data points are automatically synchronized.
For example:
Use in vimacc
All data points with parameter adl=1 in the link DPE are written by the VideoManager to the ActiveDeviceList of the vimacc runtime environment (Config).
This makes the video streams available in the camera tree of the vimacc workstation or they can be shown on the DisplayServer as usual using a CMD request.
