[MEncoder-users] Timestamp on audio and video frames?

[Levente Novák]

On Tue, 2007-06-05 at 01:49 -0700, RC wrote:
> On Tue, 05 Jun 2007 09:23:13 +0200
> Levente Novák <lnovak at dragon.unideb.hu> wrote:
> 
> > But why? Is not timestamp the exact time when a frame was grabbed?
> 
> No.  Timestamps are just relative values of the difference between
> audio and video. eg. 0, 0.1, 0.2, etc. They have nothing to do with
> real-world time.
> 

OK, I see.

> > But as there are more audio samples than video ones, after a long
> > while, there is a desync (video lag), but a non linear one.
> 
> That should not be happening at all, even with your CPU at 100%.  
> 

Yes, too bad it happens though. Maybe it has something to do with the
lavf muxer I must use to get raw DV. I will try grabbing to AVI DV and
see whether there is some improvement.

> >   what is MEncoder doing without -mc0 and -noskip specified in order
> >   to main- tain the sync?)
> 
> -mc should have no effect when capturing from a TV tuner card, only
> when playing video/audio in a container like avi/mpeg.  I did not
> realize that was your issue. 

So you say it doesn't matter what I use for recording? I don't think so
because without -mc 0 I got skipped frames (or duplicate ones, I don't
remember exactly).

Levente