[FFmpeg-devel] base av_read_frame() function for seeking in mpegps files
Sat Jul 25 13:01:59 CEST 2009
zhentan feng wrote:
> I am not clear why the parser return the wrong frame size when fist call
> av_read_frame() after seek.
> anyone explain it futher?
Well, there is probably a bug in the parser and seeking routine. I'm
currently trying to get seeking in MPEG-TS working, but it also has its
issues. There was a problem with determining proper start position of
the frame, for instance, which caused some problems. Another problem is
that the seeking routine simply picked a position within the file
approximately with specified timestamp, but didn't care about
constraints or key frames. I'm just working on this topic.
I'm afraid that MPEG-PS has a similar bug or bugs, but I don't know the
code. I don't know if anyone can "explain" it as why it doesn't work
(else it would be already fixed long time ago). So you'll have to read
the spec and analyze the code to find the bug. See also Michael's post
regarding frame/packet distribution.
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