[FFmpeg-user] converting to AAC audio duration changes

Jeanne Rich jrich at laika.com
Tue Sep 17 19:02:12 CEST 2013

Hi Mark
> I believe the other interesting thing about AAC compressed audio is
> that the audio frames overlap and the output audio is the sum of two
> overlapping two half frames. That gives a problem at the start (and
> the end) of the audio where the AAC has to be extended (backwards, for
> the start) by half a frame such that the start (and end) of the audio
> is at the right audio level.

So if I try to concat 2 movies together, is that why I am coming up with an extra frame?
and the duration directive in the concat demuxer, basically does nothing in this case?

Is there any filter that can be applied to adjust for the overlapping frames?


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