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Content channel video support

The IP VCR supports an additional video stream known as the content channel to or from each connected endpoint if the Content status field on the Settings > Content page is Enabled ( see Configuring content settings). Therefore, there are potentially three media streams between each endpoint and the IP VCR: audio, main video and content channel video. In general, the main video channel is used for motion video (i.e. high frame rate streams) and the content channel for less dynamic video such as an accompanying presentation - this is typically a high resolution, low frame rate video stream.

Support for content channel video on the IP VCR encompasses:

Recording content

When an endpoint is being recorded, that endpoint may open a content channel video stream, in addition to its main video channel. The IP VCR records both video channels, and both are available when that recording is played back.

When using the Recording console, the presence of content channel video is indicated by a "Content" icon on the right of the screen.

In a point-to-point recording, only one of the recorded endpoints is able to supply the content channel at any one time. Specifically, this means that if one endpoint is supplying the content channel stream then it must stop transmitting video before the other endpoint can start. (However, see the Automatic content handover field on the Settings > Content page.) This is in contrast to the main video channel, which both endpoints are able to transmit and receive simultaneously without restriction.

Playing back content channel video

If a recording includes a content channel video stream, that content channel stream can be played back to either other endpoints or to users viewing a recording via streaming.

Playing back to H.323/SIP endpoints

Stored content channel video can only be played back to an endpoint if that endpoint is capable of receiving a H.239 video stream (H.323 endpoints) or a BFCP stream (SIP endpoints) in addition to its main video channel. When playing back a recording which includes content channel video, an endpoint without this capability will see just the main video channel unless Playback content in main video channel is Enabled on the Settings > Content page.

Streaming content channel video

Recorded content channel streams can be played back to users' desktops via web browser-based streaming in addition to the recorded main video and audio streams. When streaming, users have the choice of playing back just the audio and main video streams, just the recorded content channel, or both together.

The play back of content channel video is accomplished through use of a Java applet, and therefore Java must be installed on any machine wanting to view the recorded content channel.

Creating customized MPEG and Windows Media Video format files

The MPEG and WM Converter Tool is a tool that converts recorded files to MPEG-1 or Windows Media Video (.wmv) format. It is available from the Support area of the web site. The MPEG and WM Converter Tool enables you to create MPEG videos or Windows Media videos that include up to two video streams and/or the content channel. The resulting encoded MPEG/'.wmv' files can be stored on PCs or servers and can be viewed via streaming applications on users' desktops.

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