Polycom 8 manual Video Conference Types

MGC WebCommander User’s Guide

Video Conference Types

Video Conferences can include both video and audio only participants. In a video conference, the participant can connect to the conference using different network connections: ISDN, H.323, ATM, MPI (serial connection) and T1-CAS (if the MCU is configured to accept T1-CAS participants in video conferences). One conference is defined for all the interface types. The usage of ATM, ISDN and H323 is defined per participant in the Participant Properties – Identification dialog box. The line rate for all participants is defined at the conference level, taking into account the maximum line rate possible with each network and endpoint.

Video conferences are categorized according to their video layout display (Video Session) and the method in which the video is processed by the MCU:

Video Switching - A conference in which all participants see the same picture (video). The current speaker is displayed in full screen on all the participants endpoints and the switching between participants is voice-activated; whenever a participant starts to speak, he or she becomes the conference speaker and is viewed on all screens. This conference type does not use the video card resources, therefore all participants in the conference must use the same line rate, and the same video settings.

This conference type does not use the MCU video resources.

In Video Switching conferences, the Highest Common Mechanism is enabled for the video parameters, allowing the system to select the best video parameters that can be supported by all the endpoints currently connected to the system, and to dynamically change them when a new endpoint joins or leaves the conference.

•Transcoding - A conference in which participants use different line rates, video, audio and data formats, while maintaining the highest video and audio capability that each participant can achieve with his or her endpoint. As in a Video Switching session, the current speaker is displayed in full screen on all the participants’ endpoints and switching between participants is voice-activated. Because each video participant is connected using the highest possible video quality, this conference type requires appropriate video card resources for processing inputs from the different endpoints. Transcoding is performed on the following: Line rate, restricted/non-restricted; Audio algorithm; Video format; Video frame rate; Aggregation mode (Bonding/H.221); different data rates

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