[PATCH] Re: [Ffmpeg-devel] FFmpeg: H.264 decoding issue

[Matthias Hopf]

On Feb 21, 07 19:43:17 +0100, Michael Niedermayer wrote:
> > If the frames are still used in a progressive fashion afterwards (e.g.
> > because PAFF isn't implemented), a buffer overflow occurs.
> 
> if the headers in h.264 say PAFF then the damn decoder should return -1
> not set picture_structure ! until PAFF is implemented at least ...

Finally I got some time to look at this issue again, and with that
information it was actually pretty easy to (hopefully) fix this issue
for good.  I tested the applied patch with two problematic streams, and
both were transcoded without crash.

> theres no umv or edges in MPEG2 and no field pics in mpeg4 and for h.264
> draw_edges with interlacing is impossible IIRC as the edges depend on
> how they are used, h.264 certainly has 10 times mores messed up interlacing
> support then any previous codec

I assume so. I guess frame handling has to get additional complexity
when PAFF is implemented, until that happens, disabling decoding of PAFF
frames is certainly the way to go.

Cheers

Matthias

-- 
Matthias Hopf <mhopf at suse.de>      __        __   __
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