[Ffmpeg-devel] av_seek_frame() on a h264 encoded MP4 file

Jack Jansen Jack.Jansen
Mon Dec 5 14:01:20 CET 2005


I try to do an av_seek_frame() on an mp4 movie with a H264 track  
inside it. This fails, because somehow the file contains an edit list  
(I'm not sure I understand this bit, because I didn't create any edit  
lists in the file). But, what is worse is that the call to  
av_seek_frame() leaves the stream in a funny state: the frames I read  
have weird blocky color effects, which doesn't go away until about 10  
seconds later (the next I frame, maybe?).

I tried debugging this but I got lost: initially I thought  
av_read_frame_flush() was to blame (which could be the case if it  
flushed the initial I frame), but my workaround of calling  
av_seek_frame(m_con, -1, 0, AVSEEK_FLAG_BYTE) after the first  
av_seek_frame call failed didn't work.

So now I turn to you: any idea what could be going on here? I can  
provide the mp4 file if needed.
--
Jack Jansen, <Jack.Jansen at cwi.nl>, http://www.cwi.nl/~jack
If I can't dance I don't want to be part of your revolution -- Emma  
Goldman






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