[FFmpeg-devel] Exposing preroll and remainder info for aac and mp3.

[Michael Niedermayer]

On Mon, Jul 16, 2012 at 09:01:09AM -0700, Raymond Toy wrote:
> On Sun, Jul 15, 2012 at 7:21 AM, Michael Niedermayer <michaelni at gmx.at>wrote:
> 
> > On Mon, Jul 09, 2012 at 11:08:07AM -0700, Dale Curtis wrote:
> > > On Wed, Jul 4, 2012 at 2:21 PM, Michael Niedermayer <michaelni at gmx.at
> > >wrote:
> > >
> > > >
> > > > just posted a patchset implementing initial silence skiping for mp3
> > > > doing the same with mov/mp4 aac should be trivial, id need a reference
> > > > sample though to make sure the aac/mov/mp4 stuff is correct. Its easy
> > > > to get it wrong without a testcase ...
> > > >
> > > > the mp3 code should be compatible with lames way of indicating the
> > > > amount of padding.
> > > >
> > > >
> > > Thanks Michael! The AAC audio files from the demo page are good samples:
> > >
> > > MP3:
> > > http://rtoy.github.com/webaudio/codec-tests/resources/media/square3.mp3
> >
> > fixed initial silence skiping
> >
> >
> > >
> > > AAC:
> > > http://rtoy.github.com/webaudio/codec-tests/resources/media/square3.m4a
> >
> > posted a patch that will fix the initial silence on this as well
> > but this file is using just 1 of 3 ways by which mp4-aac can specify
> > the initial silence.
> >
> 
> Thanks for looking into this!
> 
> 
> > Implementing the other 2 is trivial but i dont want to implement them
> > without sample files to test with. It would have a high potential
> > to introduce bugs (noone would notice if we are 5 samples off)
> > do you happen to have samples that use the other variants ?
> >
> 
> Unfortunately, no.  Can you provide some hints on what the other ways are?

sure
one way is to use edit lists the other is to use Sample Group
Structures


>  I'll try to look around to see if I can something that can produce them.

thanks

[..]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

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