[FFmpeg-devel] [PATCH] avformat/matroskaenc: do not write timebase as framerate

wm4 nfxjfg at googlemail.com
Sat Apr 28 21:05:06 EEST 2018

On Sat, 28 Apr 2018 19:52:38 +0200
Carl Eugen Hoyos <ceffmpeg at gmail.com> wrote:

> 2018-04-28 19:24 GMT+02:00, wm4 <nfxjfg at googlemail.com>:
> > If the API user doesn't set avg_frame_rate, matroskaenc will write the
> > current timebase as "default duration" for the video track. This makes
> > no sense, because the "default duration" implies the framerate of the
> > video. Since the timebase is forced to 1/1000, this will make the
> > resulting file claim 1000fps.
> >
> > Drop it and don't write the element. It's optional, so it's better not
> > to write it if the framerate is unknown.  
> (Isn't it default frame duration?)

The Matroska "spec" calls it DefaultDuration.

> Please mention ticket #6386 if you commit.

So if this was known to you, and you even made a patch, why did you
never send the patch to the list?

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