[FFmpeg-devel] [PATCH] fix timestamps in vc1testenc

Kostya kostya.shishkov
Tue Dec 7 09:09:31 CET 2010

On Tue, Dec 07, 2010 at 08:21:28AM +0100, Reimar D?ffinger wrote:
> On Tue, Dec 07, 2010 at 08:18:38AM +0100, Reimar D?ffinger wrote:
> > Hello,
> > this muxer currently when writing the timestamps does not take into
> > account the stream time base, leading to completely "random" scaling
> > of the frame time at least when using mencoder.
> > Below patch rescales the pts values like other muxers do.
> Note that I think the demuxer is broken, too.
> It does av_set_pts_info on the fps value in the header, but like
> for WMV that value is just a kind of average, and rounded to
> full FPS on top, it really should only set r_frame_rate and always
> got by pts.
> However I do not know if there are any (particularly the official test
> streams) where this might cause an issue.

The spec says that if you gor FPS value value != escape (0xFFFF IIRC)
then it should use constant frame rate otherwise it's VFR with time_base

And I wonder why all muxers should rescale PTS.

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