Polycom DOC2702A User Manual

Polycom RealPresence Collaboration Server (RMX) 1500/2000/4000 Administrator’s Guide 

Polycom, Inc.

Although any combination of CIF, SD and HD connections is supported in all CP 

conferences, the following rules apply:
•

In a 1X1 Video Layout:
—

SD: If the speaker transmits CIF, the MCU will send CIF to all participants, 

including the SD participants. In any other layout the MCU will transmit to each 

participant at the participant’s sending resolution.

—

HD: The MCU transmits speaker resolution (including input from HD 

participants) at up to SD resolution. If 1x1 is the requested layout for the entire 

duration of the conference, set the conference to HD Video Switching mode. 

•

In asymmetrical Video Layouts:
—

SD: A participant in the large frame that sends CIF is displayed in CIF.

—

HD: Where participants’ video windows are different sizes, the RMX transmits HD 

and receives SD or lower resolutions.

•

In panoramic Video Layouts:
—

SD: Participants that send CIF also receive CIF.

—

HD: the RMX transmits HD and receives SD or lower resolutions, the RMX scales 

images from SD to HD resolution.

The H.264 High Profile is a new addition to the H.264 video protocol suite. It uses the most 

efficient video data compression algorithms to even further reduce bandwidth requirements 

for video data streams.
Video quality is maintained at bit rates that are up to 50% lower than previously required. 

For example, a 512Kbps call will have the video quality of a 1Mbps HD call while a 1Mbps 
HD call has higher video quality at the same (1Mbps) bit rate.

•

H.264 High Profile is supported with MPMx cards only.

•

H.264 High Profile is supported in H.323, SIP and ISDN networking environments.

•

H.264 High Profile is supported in Continuous Presence conferences at all bit rates, video 

resolutions and layouts.

•

H.264 High Profile is the first protocol declared by the RMX, to ensure that endpoints 

that support the protocol will connect using it.
Setting minimum bit rate thresholds that are lower than the default may affect the video 

quality of endpoints that do not support the H.264 High Profile.

•

For monitoring purposes, the RMX and endpoint H.264 High Profile capability is listed 

in the Participant Properties - H.245 and SDP tabs for H.323 participants and SIP 

participants respectively. 

For more information see "IP Participant Properties” on page

.

•

H.264 High Profile is not supported:
—

In MPM and MPM+ card Configuration Modes

H.264 High-Profile should be used when all or most endpoints support it.