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 Tuesday, May 09, 2006

SG16 completed work on a new scalable voice codec - G729.1 - that will significantly improve voice quality in VoIP calls by offering wideband quality. Wideband telephony gives more natural sounding voice and greatly improves intelligibility and listening comfort.

G.729.1 extends the ITU-T G.729 speech coding standard widely used in VoIP systems and is fully interoperable with it. It will allow smooth transition from narrow band (300-3400 Hz) "PSTN" quality telephony to high quality wideband (50-7000Hz) telephony over IP and efficient deployment in existing infrastructures.

G.729.1 can operate at 12 bit rates from 32 kbit/s down to 8 kbit/s with wideband quality above 14kbit/s to dynamically provide the optimum voice quality according to service and network constraints: The bit rate can be adjusted "on-the-fly" during a call by simple truncation of the "embedded" bitstream at any point of the communication chain such as gateways or other devices combining multiple data streams. This highly flexible bit rate adaptation will avoid network congestion and the dropping of packets that severely impair the overall quality.