Re: [codec] #15: Efficiently combine pre-encoded audio

Jean-Marc Valin <jean-marc.valin@octasic.com> Wed, 12 May 2010 15:56 UTC

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Subject: Re: [codec] #15: Efficiently combine pre-encoded audio
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Benjamin M. Schwartz wrote:
> The cheapest solution, of course, is transmit-side activity detection.
> Maybe we need to specify a way for a receiver to request that the
> transmitter employ (or not employ) VAD.

I think you can do better than an encoder VAD. All you need to do is make 
sure that the relevant information you need for a VAD can easily be decoded 
from the bit-stream without having to do a full decoding. For example, if 
you're able to easily extract the gain and spectral envelope, you can do a 
VAD based on that without even having to look at the other parameters in 
the bit-stream.

	Jean-Marc