[MEncoder-users] mencoder and dvdauthor

[D Richard Felker III]

On Mon, Dec 13, 2004 at 12:50:03PM +1100, Peter Hartshorn wrote:
> On Mon, 13 Dec 2004 12:51 pm, D Richard Felker III wrote:
> > On Mon, Dec 13, 2004 at 08:24:55AM +1100, Peter Hartshorn wrote:
> > > This is what I do:
> > >
> > > two pass encoding, mpeg2 video, ac3 audio, mpeg container
> > >
> > > 	mencoder -ovc frameno -oac lavc -lavcopts acodec=ac3:abitrate=448
> > > rip.avi -o frameno.avi
> >
> > the audio prepass (frameno) is a very bad idea, imo. you really need
> > to use vf_harddup with mpeg output; otherwise if there are any
> > 'duplicate frame' messages you'll have a broken mpeg file as output,
> > and broken a/v sync. and the frameno nonsense is incompatible with any
> > filters that affect frame dropping, which includes vf_harddup.
> 
> I've found that using -noskip and -mc 0 for all passes removed any sync 
> problems.

This will work, _IF_ your DVD is nicely mastered. Many DVDs are
missing a short segment of sound at the beginning of each chapter or
vob file, and if so, you'll get an increased a/v desync by this amount
every chapter, which will total up to more than a second by the end of
the movie.

If you haven't encountered this, good, you're lucky. :)
But be careful, I've found several DVDs like that.

Rich