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

"Benjamin M. Schwartz" <bmschwar@fas.harvard.edu> Wed, 12 May 2010 17:02 UTC

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Date: Wed, 12 May 2010 12:43:57 -0400
From: "Benjamin M. Schwartz" <bmschwar@fas.harvard.edu>
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To: Jean-Marc Valin <jean-marc.valin@octasic.com>
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Cc: codec@ietf.org
Subject: Re: [codec] #15: Efficiently combine pre-encoded audio
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On 05/12/2010 12:37 PM, Jean-Marc Valin wrote:
> Benjamin M. Schwartz wrote:
>> I think I failed to communicate that by VAD I mean _not sending packets_
>> during inactivity. For the packets that are sent, the overhead should
>> average much less than 1 bit per frame.
>
> What you're describing is called DTX (discontinuous transmission).

Oops. Right.  What I'm trying to say is that DTX, based on encoder-side 
VAD, also greatly reduces the (average) computational burden on a 
conference mixer.  Of course, if everyone's really talking at once then 
VAD can't help.

--Ben