[FFmpeg-devel] [PATCH] Allow autodetecting PS and SBR for AAC without extradata.

Reimar Döffinger Reimar.Doeffinger at gmx.de
Tue Aug 16 20:07:48 CEST 2011


On Tue, Aug 16, 2011 at 08:45:50AM +0000, Carl Eugen Hoyos wrote:
> Michael Niedermayer <michaelni <at> gmx.at> writes:
> > On Wed, Aug 10, 2011 at 09:02:08PM +0200, Reimar Döffinger wrote:
> > > This was possible before and was broken when this code was added.
> 
> > > +        ac->m4ac.sbr = -1;
> > > +        ac->m4ac.ps  = -1;
> 
> > iam CCing that to alex, as i think he wrote this and might have some
> > comments
> 
> Alex believes he has written above patch:
> http://lists.libav.org/pipermail/libav-devel/2011-August/009401.html

Did someone actually test it?
With only that any broken (well, as long as it is not too broken)
first frame will cause the configuration to be locked and after
that you will run straight into the
"Implicit SBR was found with a first occurrence after the first frame."
message.
Without the other part of my patch this will only work with some
theoretical perfect streams, but not with any real-world raw streams.
Sample attached.
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