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 Thursday, December 07, 2006
Study Group 16 will start work in a new area, generic sound activity detection (GSAD).

Voice activity detection (VAD) is widely used in telecommunications networks as a means of differentiating between wanted and unwanted in-band audio signals, for example to obtain trunking efficiency in circuit multiplication equipment; to ensure correct operation of echo control and other signal enhancement devices etc.

The proposal for generic sound activity detection (GSAD) is motivated by two problems.

1.         With rapid changes in the telecommunication network environment, more and more multimedia services are being provided. Although the network is evolving from a voice to a multimedia network, most VAD algorithms are still mainly designed to handle voice signals and can not work properly in the presence of rich audio signals, which include voice, music, background environmental noise, information tones etc.

2.         Historically, VAD algorithms have been developed separately for individual network elements and applications, and there are currently numerous VAD algorithms. However, they are based on different principles, which make it difficult to provide common performance enhancements across all VADs.

Therefore it is seen as beneficial to develop a generic sound (rather than voice) activity detector, which can be applied across a range of applications. The benefits from a standardised GSAD are predicted to be:

           Enhanced performance to deal with new types of in-band audio signals

           Reduced development time and cost for new equipment requiring sound activity detection, eg codecs, circuit multiplication equipment, echo control, signal enhancement devices, VoIP gateways, terminal adapters etc.

         Opportunity for use in existing speech and audio coders which do not include VAD.