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I find that vlc (a la ffmpeg) doesn't implement the divx codec properly in some cases.

In vlc, some of the videos that i have get slower the farther along you are in the playback stream. Yet with the Divx Player, the media plays back fine.

It's only for some media, but it's a problem nonetheless. I suspect that it may have something to do with it being a somewhat reverse-engineered codec in ffmpeg?



DivX video is just standard MPEG-4 ASP, if ffmpeg doesn't play it in time and absolutely bit-perfectly then file a bug.


Incorrect audio-sync was a known issue back in the early days of MPEG4 encoding.

Getting it right was very, very hard, and some tools even came with options to "tweak" the output-stream to get things synched up, specifically tailored for the behaviour of the Frauenhofer MP3 decoder.

I suspect some videos encoded using these tools may render and synch "incorrectly" on newer players not aware of the workaround done in the past to make improper codecs behave properly, even though they may be 100% within spec.

I'm guessing the DivX-player (which sounds like a very stuck in the past kind of thing) uses old codecs and are able to account for this, by not following spec while rendering these "tweaked" video-files.


Hello,

I would be very interested to fix all that.

Please mail me to give me samples, and I'll do my best to fix it.




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