Справочник Пользователя для Polycom 7.5
MGC Manager User’s Guide - Volume I
4-21
Video Conferences
Video Conferences can include both Video and Audio as well as Audio Only
participants. In a video session, participants can connect to the conference
using different network connections: ISDN, IP (H.323 and SIP), ATM and
MPI (serial connection). One conference is defined for all the interface types.
ATM, ISDN and IP usage is configured per participant, though the line rate
for all participants is defined per conference, taking into account the line rate
range and capacity available for each network and endpoint.
participants. In a video session, participants can connect to the conference
using different network connections: ISDN, IP (H.323 and SIP), ATM and
MPI (serial connection). One conference is defined for all the interface types.
ATM, ISDN and IP usage is configured per participant, though the line rate
for all participants is defined per conference, taking into account the line rate
range and capacity available for each network and endpoint.
Video Session Types
The video session type determines the video display options (full screen or
split screen with all participants viewed simultaneously) and the method in
which the video session is processed by the MCU (whether all participants
connect using the same line rate and video parameters without using video
resources, or each one uses the endpoint's capabilities).
split screen with all participants viewed simultaneously) and the method in
which the video session is processed by the MCU (whether all participants
connect using the same line rate and video parameters without using video
resources, or each one uses the endpoint's capabilities).
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,
while the speaker sees the previous speaker. 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. Since this conference type
does not use video card resources, all participants in the conference must use
the same line rate and video parameters such as video protocol, frame rate,
annexes and interlaced video mode.
current speaker is displayed in full screen on all the participants' endpoints,
while the speaker sees the previous speaker. 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. Since this conference type
does not use video card resources, all participants in the conference must use
the same line rate and video parameters such as video protocol, frame rate,
annexes and interlaced video mode.
In Video Switching conferences, the Highest Common Mechanism can be
enabled for the video parameters. This allows 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.
enabled for the video parameters. This allows 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 can use different line rates and video,
audio and data formats while maintaining the highest video and audio
capabilities that they can achieve with their endpoints. As in Video Switching
sessions, 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
audio and data formats while maintaining the highest video and audio
capabilities that they can achieve with their endpoints. As in Video Switching
sessions, 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