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VAD implementation in G.723.1?

Started by Unknown June 15, 2005
Hi,

I wanted to know how Voice Activity Detection (VAD) is handled in
G.723.1 speech codec. How silence is detected and what parameters are
passed to the decoder? Also what the decoder does in this case? I
appreciate any help on this.

hitesh_dj

The ITU web site sells the G.723.1 spec and code for a reasonable fee. 
(<$100 US).

A google search turned up the following:

   http://www.absoluteastronomy.com/encyclopedia/S/Sp/Speex.htm

A google GROUP search turned some good results too:

There are lots of companies selling the code on various CPU 
architectures.  There used to be a comp.speech UseNet group.  Check 
their archives too.

regards,

Dan

hitesh_dj@yahoo.com wrote:
> Hi, > > I wanted to know how Voice Activity Detection (VAD) is handled in > G.723.1 speech codec. How silence is detected and what parameters are > passed to the decoder? Also what the decoder does in this case? I > appreciate any help on this. > > hitesh_dj >
thanks Dan. I found some simple VAD algorithms on comp.speech but no
pointers on its implementation in G.723.1. I went thru' the G.723.1
rec. available at http://www.ece.cmu.edu/~ece796/documents/g723-1e.pdf
but it does not mention about VAD. I dont require any code or DSP
implementation. I just need the VAD algorithm as in G.723.1 in words.
any specific pointers?

hitesh_dj

Daniel A. Ash wrote:
> The ITU web site sells the G.723.1 spec and code for a reasonable fee. > (<$100 US). > > A google search turned up the following: > > http://www.absoluteastronomy.com/encyclopedia/S/Sp/Speex.htm > > A google GROUP search turned some good results too: > > There are lots of companies selling the code on various CPU > architectures. There used to be a comp.speech UseNet group. Check > their archives too. > > regards, > > Dan > > hitesh_dj@yahoo.com wrote: > > Hi, > > > > I wanted to know how Voice Activity Detection (VAD) is handled in > > G.723.1 speech codec. How silence is detected and what parameters are > > passed to the decoder? Also what the decoder does in this case? I > > appreciate any help on this. > > > > hitesh_dj > >