Subject: Re: [AVT] Sigalling for layered media -- do itgeneric or do itpayload specific

From: Andrea Lorenzo VITALI <[email-masked]>
Date: Tue, 06 Dec 2005 15:55:03 +0100

> But wouldn't that require a new RTP version including a priority field
> within the header?

This is a per-packet signaling where the header is extended. While I'm
talking about signaling via SDP. RTP should not be modified in any way.

> Or a high level payload format for all sub-payload formats using one generic
> header with priority-signaling?

Again, this is a per-packet signaling where the payload is extended. I
don't want to propose this solution.

> Both alternatives are not the best choice.

I agree with you.

> The SVC payload format will signal the dependency of layers and the
> importance of the RTP payload in a way that media aware middle-boxes will be
> able to interpret this information in an easy, fast and efficient way. 

It may be easy, fast and efficient but it is media dependent.

> That should be our main goal, not creating an all-in-one solution suitable
> for every purpose.

I'm not talking about a silver bullet. I don't want an "all-in-one"
aimed to nothing in particular (and, because of this, not efficient).

I would like to talk about a very specific signaling of dependency and
importance. The signaling should be media-independent. Should be done in
a similar way with respect to RFC 3388.

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   Andrea VITALI                            [email-masked]

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From: Andrea Lorenzo VITALI <[email-masked]>
Date: Tue, 06 Dec 2005 15:31:54 +0100

I agree with you.

   STMicroelectronics