[MPlayer-users] vobs and broken time codes/reference clock

[Nico Sabbi]

Il giorno ven, 08/05/2009 alle 22.16 -0700, Mike Castle ha scritto:
> The following may not all be mplayer related, but I'm hoping I can get
> some advice from users here as well.
> 
> I have a DVD where, when I use -dumpstream on it, results in a vob
> where, about 2/3rds of the way through the movie, the time code resets
> (amusingly enough at a scene that display a big REBOOT).
> 
> This also happens if I copy out the vob using libdvdnav's menus.c example code.
> 
> When I play the track using  mplayer dvdnav://30 (on the disc in
> question, I must use dvdnav: as dvd: does not work), it displays the
> time code accurately.   But on the dumped stream, -osdlevel 3 shows
> the movie to end around 1:10 or so, but actuallky plays a bit longer
> than that, then starts the counter down at 0:00 again.
> 
> When I use a tool like ccextractor on the vob
> (http://ccextractor.sf.net) to dump a .srt file, it displays a message
> like:
> 
>  73%  |  70:53
> Warning: Reference clock has changed abruptly (-4303 seconds), attempting to syn
> chronize
> Last sync PTS value: 387294997
> Current PTS value: 17607
> 
> 
> Well, ccextractor fixes the timestamps on the closed captioning, but
> of course, when I play back the vob using the .srt file, the last 3rd
> of the movie is all out of whack (instead redisplaying the ones from
> earlier in the movie).
> 
> 
> So, I would like to either have the ability to fix the vob or to avoid
> the problem in the first place.
> 
> I'm guessing that mplayer's dumpstream (at least for dvd's) is pretty
> much the same as the menus.c example:  Just take the packets from
> libdvdnav and put them straight to disk, with no mpeg2 processing at
> all.
> 
> >From what I understand, mencoder's tsaf option might work, but that
> would mean processing the .vob multiple times, once for each video and
> audio track, then remuxing them.  Or am I misreading the man page?
> 
> 
> In some research that I've done, it looks like a Windows tool named
> VideoRedo has a Quick Stream Fix facility would fixup the reference
> clock on streams like this,  But I have not, as yet, been able to find
> a tool that would work on unix.
> 
> 
> For the most part, I'm pretty happy with mplayer's -dumpstream
> facility.  If I'm missing something here, though, it'd be great to
> figure out what it was.
> 
> Any anyone has any recommendations on how to solve this problem, I'd
> be appreciative.
> 
> mrc

when playing dvds the time shown on the OSD is the time reported in the
IFO files (that is linear and correct), thus a value possibly different
from the PTSs in the VOB files. You can remux the audio and video
streams with mencoder -of mpeg -mpegopts format=dvd:tsaf ... , then dump
the vobsub information to get the palette values, dvdunauthor the subs
and finally dvdauthor the final mpg + subs + palette with dvdauthor.
Read the docs in dvdauthor to understand how to mux it all together.