Local Conference Mixing; Voice Activity Detection (Vad) - Polycom Version 1.4.x 17 Administrator's Manual

Sip 1.4.0 soundpoint/soundstation ip sip
Table of Contents

Advertisement

Administrator Guide - SoundPoint
Central
(boot
server)
Local

3.3.3 Local Conference Mixing

The phone's audio processing subsystem contains a flexible three-party conferencing
capability
external protocol signaling is involved.

3.3.4 Voice Activity Detection (VAD)

The purpose of VAD is to conserve network bandwidth by detecting periods of rela-
tive "silence" in the transmit data path and replacing that silence efficiently with spe-
cial packets that indicate silence is occurring. For those compression algorithms
without an inherent VAD function, such as G.711, the phone is compatible with the
comprehensive codec-independent comfort noise transmission algorithm specified in
RFC 3389. This algorithm is derived from G.711 Appendix II, which defines a com-
fort noise (CN) payload format (or bit-stream) for G.711 use in packet-based, multi-
media communication systems. The phone generates CN packets (also known as
Silence Insertion Descriptor (SID) frames) and also decodes CN packets, efficiently
regenerating a facsimile of the background noise at the remote end.
Central
(boot
server)
2. On SoundStation IP
42
This restriction will be removed in future releases.
®
®
IP / SoundStation
Configuration file:
ipmid.cfg
Web Server
(if enabled)
Local Phone User
Interface
2
. This feature can be used to set up local three-party conferences where no
Configuration file:
ipmid.cfg
®
4000, conferences are not available if the G.729 codec is enabled on the phone.
Copyright © 2004 Polycom, Inc.
IP
Set the jitter buffer tuning parameters including minimum
and maximum size and shrink aggression.
For more information, see 4.6.1.6.1.2 Codec Profiles
<profiles/> on page 79.
Set the jitter buffer tuning parameters including minimum
and maximum size and shrink aggression.
Navigate to: http://<phoneIPAddress>/coreConf.htm#au
Changes are saved to local flash and backed up to <Ethernet
address>-phone.cfg on the boot server. Changes will per-
manently override global settings unless deleted via the
Reset User Settings menu selection.
None.
Enable or disable VAD and set the detection threshold.
For more information, see 4.6.1.6.10 Voice Activity
Detection <VAD/> on page 86.
Features

Advertisement

Table of Contents
loading

Table of Contents