[MPlayer-users] BUG: mencoder dvd sync

[christopher j bottaro]

On Sunday 02 February 2003 04:15 am, Corey Hickey wrote:
> Well, I've run a few tests, and the problems only start to occur with
> builds made from after the change was made.
>
> Here are the results of CVS builds made from the following times:
>
> 2003-01-16 22:30 UTC --- Works fine.
> 2003-01-16 23:00 UTC --- Works terribly; encoder skips lots of frames,
> audio sync gets worse throughout file.
> 2003-01-16 23:30 UTC --- Has the same slight desync as today.


i wrote a little perl script to document when the av sync gets above +/-0.03.

here is the output from mencoder cvs compiled a few days ago:
mencoder -oac mp3lame -lameopts abr:br=96 -ovc frameno -o frameno.avi -ofps 
23.976 -dvd 1
99% done,    0 mins remaining
AV desync detected: range 11-134791, count 134780, avg 0.051929418311324
100% done, 0 mins remaining

so pretty much the entire movie is outta sync by an avg of 0.0519...

here is output from mencoder cvs snapshot 20021210:

mencoder -oac mp3lame -lameopts abr:br=96 -ovc frameno -o frameno.avi -ofps 
23.976 -dvd 1
 0% done,    0 mins remaining
AV desync detected: range 11-19, count 8, avg 0.037
 8% done,   17 mins remaining
AV desync detected: range 73-10798, count 10725, avg 0.0513603729603725
16% done,   14 mins remaining
AV desync detected: range 10814-21931, count 11117, avg 0.0511943869749031
23% done,   13 mins remaining
AV desync detected: range 21944-32032, count 10088, avg 0.0504846352101498
31% done,   11 mins remaining
AV desync detected: range 32047-43361, count 11314, avg 0.04972131872017
34% done,   10 mins remaining
AV desync detected: range 43376-46423, count 3047, avg 0.0492792911060067
38% done,    9 mins remaining
AV desync detected: range 46481-51646, count 5165, avg 0.0492526621490805
42% done,    8 mins remaining
AV desync detected: range 51649-56978, count 5329, avg 0.0494473634828301
51% done,    7 mins remaining
AV desync detected: range 56992-68704, count 11712, avg 0.0495035006830606
60% done,    5 mins remaining
AV desync detected: range 80129-80134, count 5, avg 0.0322
76% done,    3 mins remaining
AV desync detected: range 101481-101484, count 3, avg 0.034
84% done,    2 mins remaining
AV desync detected: range 112702-112705, count 3, avg 0.032
97% done,    0 mins remaining
AV desync detected: range 129873-129876, count 3, avg 0.034
99% done,    0 mins remaining
AV desync detected: range 134785-134798, count 14, avg 0.0545
100% done, 0 mins remaining

range refers to which frames, count means how many consecutive frames in that 
range, and avg is the avg av desync that mencoder spits out for those frames.

the dec 10th snapshot seems to do a bit better, but there are still large 
chunks that are outta sync by a significant amount...

the dvd being encoded is roadtrip.

so both old and new mencoder don't do well with this dvd.  sometimes old 
mencoder will encoded a dvd perfectly, while new mencoder won't and vice 
versa.  it stinks cuz i have to experiement to see which mencoder to use for 
which dvd.  it stinks even more when both mencoders don't work...=/

-- christopher