[NUT-devel] NUT spec review - chapters

[Rich Felker]

On Sun, Feb 10, 2008 at 05:56:32AM +0100, Michael Niedermayer wrote:
> On Sat, Feb 09, 2008 at 10:54:13PM -0500, Rich Felker wrote:
> [..]
> > > Having seperate timebases for begin and end would be better than above. But
> > > the most important part you forgot is that chapers
> > > might end at slightly different spots in streams. If you want to specify
> > > this exactly then this change wont get you any closer to it. If you dont
> > > you can as well just always use the chapter start/end of the video or audio
> > > stream. Its not much less accurate and theres no overlap/gap problem.
> > 
> > Indeed, you can use the same timebase for all the chapter boundaries,
> > but this seems rather limiting and artificial.
> 
> I dunno, 
> Chapter 1 begin video frame 500, end audio sample 99000
> Chapter 2 begiin subtitle sample 87, end video sample 876
> 
> looks a little strange, having it all in one timebase looks better IMHO,
> also theres the issue that practically every demuxer will convert it
> immedeatly after loading to a common timebase. I would at least in
> lavf, its too much of a mess to work with such timestamps.

It could be converted to the gcd timebase by the demuxer
implementation. Lame implementations also just might use double or
something...

> > > Iam very strogly against breaking compatibility to move from one restricted
> > > system which you thought sufficient in the past to a slightly differen one
> > > you consider sufficient now.
> > 
> > Alright. Even though there is no implementation of chapters at this
> > time..
> 
> hmm, well if thats true we might be able to cheat but i still think that
> maybe this isnt all that much of an improvment.
> being able to specify chapters in any timebase one wants seems sufficient.
> Having a timebase per timestamp seems like an overkill ...

That's probably okay too...

Rich