[FFmpeg-devel] [Ffmpeg-user] chroma errors on movie file.

[Baptiste Coudurier]

Baptiste Coudurier wrote:
> Hi Aurelien,
> 
> Aurelien Jacobs wrote:
>> On Fri, 10 Aug 2007 07:43:27 +0200
>> Benjamin Larsson <banan at ludd.ltu.se> wrote:
>>
>>> gga wrote:
>>>> gga wrote:
>>>>> Using latest svn ffmpeg, this file:
>>>>> http://www.encuadre.com.ar/videos/manfredi/OLOCOONS_O3.mov
>>>>>
>>>>> results in ffmpeg decoding the video incorrectly, with errors about
>>>>> chroma, among others.  This is using an svq3 codec.
>>>>> Can anyone confirm?
>>>>>
>>>> Oh yes, I should mention this is with ffplay itself.  mplayer or vlc
>>>> will read the file fine with their demuxers/decoders.
>>>>
>>>>
>>> Works for me without any visible errors with an old ffplay version. Get
>>> lots of errors with a fairly new one. So the report seems to be valid.
>> Confirmed. The bug seems to be demuxer related. It works fine with
>> mplayer's native demuxer but don't work with mplayer -demuxer lavf.
>> Baptiste ?
> 
> It seems, yes. I'll be in vacation tonight for 2 weeks, so I won't have
> any computer to look at it :/
> 

Ok, problem is that "fiel" atom parsing overwrites extradata in
mov_read_extradata (overwrite 'SMI ' atom), so decoder fails to decode
stream. Attached patch makes mov_read_extradata appending atoms in
extradata. svq3 decoder will search for 'SEQH' sequence (contained in
'SMI ') in extradata.

Michael is it ok for you ?

-- 
Baptiste COUDURIER                              GnuPG Key Id: 0x5C1ABAAA
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