[FFmpeg-devel] [PATCH] Fix empty G-VOP header decoding in MPEG-4

[Anatoly Nenashev]

On 09.02.2011 23:30, Anatoly Nenashev wrote:
> On 08.02.2011 22:00, M?ns Rullg?rd wrote:
>> Anatoly Nenashev<anatoly.nenashev at ovsoft.ru>  writes:
>>
>>> Hi all!
>>> There are some cameras which send mpeg-4 streams with empty G-VOP 
>>> header.
>>> This part of stream looks like this:
>>> ... 00 00 01 B3 00 00 00 01 B6 ...
>>> Sample file uploaded in issue 2592.
>>> FFmpeg reports "header damaged" and ignores first I-frame in G-VOP.
>>> Attached patch fix this problem.
>>>
>>> Anatoly.
>  [...]
>>> Looking at this, I wonder why this is there at all.  The s->time_base
>>> field is only used to incorrectly set the pts field of the decoded
>>> frame (now I understand why those values always are wrong).  The
>>> actual PTS is passed from the input packet to the pkt_pts field of the
>>> output frame.
>>>
>>> IMO this nonsense should be removed.  The time_code field in the
>>> bitstream has nothing to do with PTS.
>>>
>
> Hmm... So, if I understand you clearly, we just can ignore GOP header 
> as done in attached patch.
>
>    
Or this version would be better.

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