[Theora-dev] A/V sync strategies

Keenan Pepper keenanpepper at gmail.com
Sat Mar 5 17:32:57 PST 2005

Ivan Popov wrote:
> I can not tell if your guess about the cause of the problem is right or not,
> but I'd appreciate if you can give a run the theora-encoder script
> and see if it breaks in the same way (it shouldn't).

Sorry, but I ran the script using the example_encoder from theora svn 
and mplayer 1.0pre6, and the sync is off by a quarter of a second after 
a half hour. I'm fairly sure I have the correct framerate, because I 
used "-f 24000 -F 1001", and the audio is actually lagging behind the 
video, indicating the frame rate should be lower than 24000/1001 on average.

> The script runs mplayer and as such does not make the sync a "Theora
> issue", the data which theoraenc is fed with should be correct
> and that's enough.

So this is a problem with mplayer then? I thought mplayer used feedback 
from the sound card and video driver to adjust the sync, which obviously 
cannot work when it's just dumping the raw material to a pipe.

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