Avaya Scopia XT Series User Manual page 69

H.245
H.245 is the protocol used to negotiate call parameters between endpoints, and can control a remote
endpoint from your local endpoint. It is part of the H.323 set of protocols.
H.261
H.261 is an older protocol used to compress CIF and QCIF video resolutions. This protocol is not
supported by the XT Series.
H.263
H.263 is an older a protocol used to compress video. It is an enhancement to the H.261 protocol.
H.264
H.264 is a widespread protocol used with SIP and H.323 endpoints, which defines video compression.
Compression algorithms include 4x4 transforms and a basic motion comparison algorithm called P-
slices. There are several profiles within H.264. The default profile is the H.264 Baseline Profile, but
H.264 High Profile uses more sophisticated compression techniques.
H.264 Baseline Profile
See H.264
H.264 High Profile
H.264 High Profile is a standard for compressing video by up to 25% over the H.264 Baseline Profile,
enabling high definition calls to be held over lower call speeds. It requires both sides of the transmission
(sending and receiving endpoints) to support this protocol. H.264 High Profile uses compression
algorithms like:
• CABAC compression (Context-Based Adaptive Binary Arithmetic Coding)
• 8x8 transforms which more effectively compress images containing areas of high correlation
These compression algorithms demand higher computation requirements, which are offered with the
dedicated hardware available in Scopia
videoconferencing requires that both the sender and receiver's endpoints support it. This is different from
SVC which is an adaptive technology working to improve quality even when only one side supports the
standard.
H.320
H.320 is a protocol for defining videoconferencing over ISDN networks.
User Guide for Avaya Video Collaboration Solution for IP Office
Version 8.3
on page 69.
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Solution components. Using H.264 High Profile in
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Glossary of Terms for Scopia Solution | 69