[theora] ffmpeg2theora 0.25 synchronization issues when converting from .mov

[Jason Self]

I have also been experiencing problems with A/V sync ever since I  
started using ffmpeg2theora well over a year ago. It seems to be  
longstanding problem. Have you tried it with a recent build of FFmpeg  
proper? I did and continued to have A/V sync problems.

This seems to point the finger squarely at FFmpeg itself, not  
ffmpeg2theora. I've reported it to the Ffmpeg developers, but no one  
seems interested in addressing it.

I also mentioned it to the ffmpeg2theora developer but have not  
received a reply.

Something that I found interesting is that another video encoder  
(HandBrake - http://handbrake.fr) makes use of libavcodec and  
libavformat from the FFmpeg project and doesn't have these problems.  
I'm not sure what they do differently, although this may provide a  
clue: http://trac.handbrake.fr/wiki/LibHandBrakeSync.

That said, perhaps there could be some type of community effort to  
address the sync problems instead? I can provide copies of problematic  
media if anyone is interested. In consideration of how long this has  
been happening, how little interest there seems to be in addressing  
it, and how much it would benefit the Theora community, I would be  
happy to offer up a bounty with my own money to anyone that is willing  
to address the problem once and for all.

On Sep 30, 2009, at 11:32 PM, Juhani Jaakola  
<juhani.jaakola at kolumbus.fi> wrote:

> Yes, I have the same problem. I have tested versions 0.24 and 0.25.
>
> Please see thread "[theora] Accelerated video output with  
> ffmpeg2theora 0.24" in the archives of this mailing list.
>
> I have an AVI container with this stream:
>
>    Stream #0.0: Video: rawvideo, yuyv422, 720x576, 25.02 tbr, 25.02  
> tbn, 25.02 tbc
>
> Regards, JJ
>
> Andrew Chew [andrew at okashistudios.com] kirjoitti:
>> Has anyone noticed this?  I have a video made with Final Cut Pro,
>> which I convert to .mov via Compressor.  This .mov file plays back
>> fine in Quicktime.  But when I then use ffmpeg2theora to convert to
>> ogv, the video seems to play back too fast compared to the audio (I'm
>> using VLC 1.0.2, the latest I believe, to play back the ogv file, and
>> I also have an app that uses the recently released libtheora 1.1, and
>> I see the same sped-up video as with VLC).
>>
>> I'm wondering if it's a known problem, or if I'm the first to see  
>> this.
>> _______________________________________________
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>
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