[FFmpeg-devel] [RFC] Frame accurate seeking

Karl Blomster kalle
Wed Dec 30 16:07:19 CET 2009

Artur Bodera wrote:
>> Also, feature requests do not belong on this list, and even for a
>> feature request this lacks an exact description of _what_ you want.
> Sure, unless I provide a solution, which I did:
> http://github.com/lbrandy/ffmpeg-fas

FFmpegSource (http://code.google.com/p/ffmpegsource) does something similar. 
That is, provides a simplified API that gives you frame-accurate decoding but 
not much else. Some people find that quite useful, but from what I read about 
what you actually want to do, it won't help you at all.

> The use case is described here:
> http://archives.free.net.ph/message/20091228.114853.066bc91b.en.html
> I'm looking for a way to split a stream into parts without decoding it to
> rawvideo or transcoding 2 times. I thought it would be feasible using
> gop/fps calculations, but it seems that the time seeking is a bit "jerky"
> and -vframes does not help either when you need 2 matching chunks (the
> second one needs to start where the first one ended, frame-wise, and you can
> not seek by frames = dead in the water).

If you can accept splitting only at I(DR)-frames, mkvmerge can do this for you. 
    You can always demux/remux back to MP4 later. :V

Karl Blomster

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