[FFmpeg-devel] [PATCH] avformat/matroskaenc: Allow changing the time stamp precision via option

[Nicolas George]

Michael Fabian 'Xaymar' Dirks (12021-05-20):
> Well, it's a combination of many things really, not bad math itself.
> 1ms works perfectly for the frame rates of 1, 2, 4, 5, 8, 10, 20, 25,
> 40, 50, 100, 125, 200, 250, 500, and 1000. For any other rate, you
> will have to look at the actual timestamp of N clusters and M blocks,
> where N and M are undefined. N and M are undefined because there is no
> solution that works for every rate, other than having a per-track
> rational time base
> (https://github.com/ietf-wg-cellar/matroska-specification/pull/425).
> 
> If there were zero dropped/skipped frames in the encoding process (we
> have a packet for every frame), then it can be worked around by
> looking ahead for 1 second, but that is a lot to ask from an
> application just to know the actual rate.

Why would an application need to know the actual frame rate with so much
precision?

> Matroska is far from perfect as it is right now, so more vocal input
> on the IETF standardization process for Matroska/WebM might be
> helpful.

To be really helpful, it is necessary to understand the issue properly.
In my experience, most people who complain about the precision of
timestamps are using them wrong.

Regards,

-- 
  Nicolas George
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