[MPlayer-DOCS] CVS: main/DOCS/man/en mplayer.1,1.813,1.814

[Diego Biurrun]

Reimar Döffinger writes:
> > > > > @@ -682,6 +682,8 @@
> > > > >  .B \-sstep <sec>
> > > > >  Display one frame every <sec> seconds.
> > > > >  Useful for slideshows.
> > > > > +This uses normal seeking, and thus is just as inexact (i.e. with most formats
> > > > > +you will get one frame between every <sec> and <sec> + 120 seconds).
> > > > 
> > > > 120 sec is 2 minutes. Is -sstep really that inacurate?
> > > 
> > > Well, I guess I should have written "with some files" instead of "with
> > > most formats". But yes, you usually can seek only to keyframes and e.g. with many
> > > DivX files I have they are sometimes 2 mins or further apart (maybe those are bad encodes
> > > but still).
> > 
> > this is nonsense, i've never seen keyframes more than 20 seconds or so
> > apart, and even that's extreme. imo you're thinking 120 _seconds_
> > instead of 120 _frames_ (which is a common minimal keyframe interval;
> > typical is 250-300).
> 
> Actually yes and no. I have to admit that I thought of 400 frames. No
> idea how I got to that 120 seconds... Shows how much I was thinking
> before replying :-(.
> I changed it to say 20 seconds (the inaccuracy can actually be almost
> twice the keyframe interval), but I guess that description could still be improved...

I've removed our guesses about keyframe intervals, some quick testing
with a few samples indicate much lower keyframe intervals and random
failures.  No estimate is better than a wildly inaccurate one.

Diego