[speex-dev] Query r/e multiple decoder reset...

Kerry L. Bonin kerry at vscape.com
Wed Dec 18 08:37:43 PST 2002

Hello!  I should have asked this earlier, but...  :)

We're returning to voice processing in our app now, in which we're trying 
to achieve n-way full duplex voice in a 3d environment.  Since Speex is a 
single voice stream CODEC, we've been looking at having each client upload 
its stream to the servers, which multiplex several spatially nearby active 
channels back down to the client.  (Like we did at OnLive where several of 
us once worked.)

To do this, we're looking at having ~4 decoders running per client to 
handle up to ~4 active downchannels.  The only catch is that these need to 
handle arbitrary sources. To achieve this, we seem to need to be able to 
reset a decoder to handle a stream from another source, ideally without 
having to free its resources, etc.

Is there any clean way to do this, and/or can such a function be added to 
the API?

Another query - we're currently running VAD in our layer above Speex.  Is 
there any way to query the encoder as to its VAD status after encoding?  It 
would be nice if we could leave all the raw data processing within Speex, 
all we're missing is a way to determine if a packet contained enough energy 
to warrant transmission.

Finally - has anyone looked at or be able to point me to papers on 
integration of vocal tract modeling into CELP systems?  I'm very interested 
in reproducing some of the intra-CODEC features we had at OnLive that 
allowed primitive mouth placement from the audio stream.  Its on our long 
term target list, and I was curious if anyone had any suggestions...


<p>--- >8 ----
List archives:  http://www.xiph.org/archives/
Ogg project homepage: http://www.xiph.org/ogg/
To unsubscribe from this list, send a message to 'speex-dev-request at xiph.org'
containing only the word 'unsubscribe' in the body.  No subject is needed.
Unsubscribe messages sent to the list will be ignored/filtered.

More information about the Speex-dev mailing list