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

From: "codec issue tracker" <[email-masked]>
Date: Thu, 24 Jun 2010 15:22:22 -0000

#15: Efficiently combine pre-encoded audio
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 Reporter:  hoene@…                 |       Owner:     
     Type:  enhancement             |      Status:  new
 Priority:  minor                   |   Milestone:     
Component:  requirements            |     Version:     
 Severity:  Active WG Document      |    Keywords:     
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Comment(by hoene@…):

 [Roman Shpount]: I would like to remind that this issue is not about
 efficient VAD, but about efficiently combining pre-encoded streams. There
 are two use cases that I can think of:

 a. Conference servers, where the active speaker was determined by either
 receiver or decoder side VAD. As it was mentioned before, it is possible
 to implement an efficient decoder side VAD without implementing a complete
 decoder. If we can combine pre-encoded audio we can combine multiple
 streams on the conference server without going through decoder/encoder
 cycle greatly decreasing both CPU requirements and mixer delay.

 b. Announcement and IVR servers, where a small set of pre-encoded
 announcements are played to the user. Standard network or IVR
 announcements can be encoded once and efficiently inserted or combined
 into audio stream. If pre-encoded audio is supported and the client
 supports AVT tones, it is trivial to develop a very efficient IVR server
 which does not require any CODEC encoding or decoding.

-- 
Ticket URL: <https://svn.tools.ietf.org/wg/codec/trac/ticket/15#comment:3>
codec <http://tools.ietf.org/codec/>