Subject: [Sipping] Media grouping in transcoding framework

From: "Geir Arne Sandbakken" <[email-masked]>
Date: Thu, 10 Mar 2005 19:20:17 +0100

Gonzalo,

Just to recap our brief discussion.

The framework document talks about end-points invoking services on a
stream basis for the Third Party Call Control Transaction model. It
could be useful to have some language that addresses stream grouping in
the framework document.  One use case is audio and video lip sync.  You
might want the transcoder to handle both streams - even if one doesn't
need transcoding - to avoid over extending the jitter buffer for the
recipient.

Geir Arne 

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From: "Gaurav Kulshreshtha" <[email-masked]>
Date: Thu, 10 Mar 2005 14:36:33 -0500

Geir,

I agree with your idea that an endpoint may want to invoke transcoding on
certain streams or all streams. It would be helpful to have some of
describing this idea to the transcoder. 

gkul

  _____  

From: [email-masked] [mailto:[email-masked]] On Behalf
Of Geir Arne Sandbakken
Sent: Thursday, March 10, 2005 1:20 PM
To: Gonzalo Camarillo
Cc: SIPPING LIST
Subject: [Sipping] Media grouping in transcoding framework

Gonzalo,

The framework document talks about end-points invoking services on a stream
basis for the Third Party Call Control Transaction model. It could be useful
to have some language that addresses stream grouping in the framework
document.  One use case is audio and video lip sync.  You might want the
transcoder to handle both streams - even if one doesn't need transcoding -
to avoid over extending the jitter buffer for the recipient.

Geir Arne

---

From: "Medhavi Bhatia" <[email-masked]>
Date: Thu, 10 Mar 2005 14:58:31 -0500

I guess the document needs to get down to the detail of RTP sessions being
transcoded. Could you describe the jitter buffer problem in some detail
which happens when we transcode one of the RTP sessions in the session. 

  _____  

Gonzalo,

Geir Arne

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From: Gonzalo Camarillo <[email-masked]>
Date: Fri, 11 Mar 2005 00:34:39 +0200

Hi,

as a clarification, this mechanism applies to a single transcoder. The 
transcoder is in the media path, and it decides which streams needs to 
be transcoded.

If folks want to do complicated stuff like sending a video to a 
transcoder and the audio to a different one, they can use the 3pcc model.

Gonzalo

Medhavi Bhatia wrote:
> I guess the document needs to get down to the detail of RTP sessions
> being transcoded. Could you describe the jitter buffer problem in some
> detail which happens when we transcode one of the RTP sessions in the
> session. 
> 
>  
> 
>   _____  
> 
> From: [email-masked] [mailto:[email-masked]] On
> Behalf Of Geir Arne Sandbakken

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