[FFmpeg-devel] [PATCH] Only output necessary NAL units in H.264 extradata in SDP

Luca Abeni lucabe72
Sun Apr 5 21:53:12 CEST 2009

Hi Loren,

On Sat, 2009-04-04 at 05:56 +0000, Loren Merritt wrote:
> >    sprop-parameter-sets:
> >        This parameter MAY be used to convey
> >        any sequence and picture parameter set NAL
> >        units (herein referred to as the initial
> >        parameter set NAL units) that MUST precede any
> >        other NAL units in decoding order.  The
> >        parameter MUST NOT be used to indicate codec
> >        capability in any capability exchange
> >        procedure.
> >
> > The way I interpret this, only SPS and PPS are allowed. Am I getting this
> > right?
> If I interpret it literally, then not even SPS/PPS are allowed.

So, now I am confused... Which NALs should go in "sprop-parameter-sets"?
(I am asking because I intended to commit the patch, but after reading
your comment I want to be sure).

When I originally read the RFC, I somehow got the impression that all
the NALs contained in the extradata are allowed to be in
sprop-parameter-sets. Now, re-reading the RFC I see that it mentions
"sequence and picture parameter set NAL units", which I assume to be SPS
and PPS... Is this wrong?


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