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TANDBERG 770/880/990 MXP
3.11.5Dual Stream (DuoVideoTF/H.239)
(Optional feature - not available on all systems)
With Dual Stream you have the opportunity to show two different live video streams simultaneously, main video and one additional source. This is handy when showing a presentation. You see the live presentation and the live video of the presenter simultaneously. When you start a presentation, Dual Stream starts automatically if both local and remote system supports Dual Stream. If one of the systems does not support Dual Stream, no second video stream will be established and your presentation will be shown as your main video.
Dual Stream is available on all systems with Natural Presenter Package installed. H.239 is the new ITU standard defining how to send two video sources simultaneously.
Example:
Start a meeting with main camera as video source. Press the presentation key on the remote control to start a PC presentation.
PC will appear as a Dual Video Stream in addition to main camera. End the Dual Stream presentation by pressing presentation key again.
In Presentation Settings, you can set Presentation Start to Manual. That means that Dual Stream will not start automatically.
Example:
Start a meeting with main camera as video source. Press the presentation key on the remote control to start a PC presentation.
A dialog box appears where you can choose to show PC as Dual Video Stream or not. This is handy if you not always want to use Dual Stream.
Dual Stream and Bandwidth
Using Dual Stream, the quality automatically downspeeds to the optimal bandwidth. This means that you need higher quality to allocate enough bandwidth for the two video streams. Dual Stream borrows bandwidth from main video stream. When Dual Stream is closed, the bandwidth is returned to the main video.
Note that when selecting the Document Camera or PC, the system will automatically request floor when connected to a MCU conference as MultiSite host* or connected to an external MCU.
* Not available on all systems.
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