[MPlayer-users] dvd pts timestamp resets are different without audio?

[Reimar Döffinger]

On Thu, Oct 27, 2011 at 10:49:16AM -0600, Roger Pack wrote:
> On Thu, Oct 27, 2011 at 4:42 AM, Nico Sabbi <nicola.sabbi at poste.it> wrote:
> > Roger Pack ha scritto:
> >>
> >> Hello all.
> >> Behold, I reveal a mystery.
> >> With some DVD's, if I play it "with audio", the PTS timestamp resets at
> >> 3498.03
> >> however, if I play it back with "-nosound" it says the reset occurs at
> >> 3499.40
> >
> > no, can't be. I don't know why, but timestamps are unaffected by the single
> > streams you play.
> 
> I agree, the MPEG timestamps you'd think would be consistent, though I
> did notice some mention under "-autosync" [1]
> "An uneven video framerate in a movie which plays fine with -nosound
> can often be helped by setting this to an integer value greater than
> 1."
> 
> I don't quite understand how sound can affect video timing, though maybe it can.
> I'm wondering if it's some "DVD format fluke" or something.  The DVD
> format seems like an odd duck.

Now you are talking about timing.
Previously you talked about time stamps.
Time stamps basically is what is stored in the video.
Timing is what you _might_ want to use them for, though sometimes it's
better not to do that.
Though in any way to do timing the other thing you need is a clock.
In MPlayer that usually is the audio clock. And autosync is to
try to clean that one up when it is very broken.