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Video Protocols and Resolution Configuration for CP Conferencing

Video Resolutions in AVC-based CP Conferencing

The Collaboration Server always attempts to connect to endpoints at the highest line rate defined for the
conference. If the connection cannot be established using the conference line rate, the Collaboration Server
attempts to connect at the next highest line rate at its highest supported resolution.
Depending on the line rate, the Collaboration Server sends video at the best possible resolution supported
by the endpoint regardless of the resolution received from the endpoint.
The video resolution is also defined by the Video Quality settings in the Profile.
The combination of frame rate and resolution affects the number of video resources required on the MCU
to support the call.
The following resolutions are supported:
CIF 352 x 288 pixels.
SD 720 x 576 pixels
HD 720p 1280 x 720 pixels.

Video Display with CIF, SD and HD Video Connections

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.
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 Collaboration Server transmits HD
and receives SD or lower resolutions.
In panoramic Video Layouts:
SD: Participants that send CIF also receive CIF.
HD: the Collaboration Server transmits HD and receives SD or lower resolutions, the
Collaboration Server scales images from SD to HD resolution.
The following video resolution information applies to AVC Conferencing Mode.
For a description of resolutions for SVC Conferencing Mode see Defining SVC and Mixed CP and
SVC Conference Profiles on page 74.