[Libav-user] Is it possible to detect unused/invalid packets (without decoding)

[wm4]

On Wed, 28 Jan 2015 15:51:53 +0200
Anton Shekhovtsov <shekh.anton at gmail.com> wrote:

> 2015-01-28 15:34 GMT+02:00 Nicolas George <george at nsup.org>:
> 
> > Le nonidi 9 pluviôse, an CCXXIII, Max Vlasov a écrit :
> > > The idea was to read all packets saving pts and keyframe flag (without
> > > decoding) and make a list of them in order of ptses. After this we have a
> > > ready FrameCount and when one needs to jump to an exact frame number
> >
> > Why do people here always want to work with frame numbers? Frame numbers
> > are
> > unreliable, they are a remnant of the time where containers could only do
> > constant FPS.
> >
> > The correct way of identifying a frame is not its number, it is its
> > timestamp.
> >
> > Regards,
> >
> > --
> >   Nicolas George
> >
> > _______________________________________________
> > Libav-user mailing list
> > Libav-user at ffmpeg.org
> > http://ffmpeg.org/mailman/listinfo/libav-user
> >
> >
> Frames are important entities if the application is video editor.
> It wants to treat video as a sequence of images. It wants discrete timeline
> where each frame is a unit.
> How about buffering 40ms of video in memory? Vague. 40 frames? Required
> memory=frame_size*40. Simple. etc

Things like FFMS2 use a complete index and a cache for this.
L-SMASH-Works (which is a different project from L-SMASH)
does something similar and is more modern, AFAIK.