[MPlayer-dev-eng] nut seeking without an index

[Rich Felker]

On Thu, Sep 08, 2005 at 07:30:25PM +0200, Michael Niedermayer wrote:
> > > But obviously this isn't true at all for subtitle streams.
> > > The key condition is that you only need to find a keyframe for stream
> > > N if there will be another non-key frame for stream N before the
> > > following keyframe for stream N.
> > 
> > no, thats wrong, it depends upon the duration of the keyframe, the
> > current definition in nut is that it lasts until the next frame
> > theres no concept for "holes" in streams like you seem to somehow
> > have invented for subtitle streams, all problems here seem to be 
> > caused by that
> > just add a 0byte keyframe for subtitle streams every second where
> > there is nothing displayed or alternatively we could add some frame 
> > duration or end-of-frame support but these will be less easy
> 
> we could also place just 1 0byte keyframe at the point where subtitles
> disapear and handle this differently from other keyframes, its also
> easy to detect by the zero size in the index on the demuxer side ...

yes but i don't see how this alone prevents having to use insanely
long backward pointers..

> furthermore we could add such a 0byte keyframe at the very end instead
> of the last-pts to indicate stream length and the length of the last
> frame

i proposed this before, and like the idea a lot. however, i think it
should be set to indicate the duration of the final packet, if
possible. this makes it possible to seemlessly join multiple nut files
at playback time while still having the correct duration for the final
frame of the first file.

rich