[MEncoder-users] [BUG] a-v sync problems with pullup, softskip (only on some DVDs)

[Corey Hickey]

D Richard Felker III wrote:

> I meant extra/fewer skips or dups at the very start of the encode.
> 

At the very beginning not much is different between the two.

Without pullup mencoder duplicates two frames and skips two frames. With 
pullup mencoder duplicates two frames, skips one frame, and doesn't 
start duplicating very many until frame 638, after which it duplicates 
dozens. If you want to see the details check:
http://fatooh.org/files/mpbug/desync2/big-nopullup.log.bz2
and:
http://fatooh.org/files/mpbug/desync2/big-pullup.log.bz2

> 
>>I also just noticed something I hadn't before: when using pullup
>>mencoder reports "Could not get buffer from pullup!" four times. I just
> 
> 
> This is very bad and should never happen.. It means something is going
> radically wrong with the buffer management. Can you help me isolate
> the problem so I can see it happen on a small clip? If not, I'll try
> to come up with a patch that would help make a more useful debug log
> for me to read when it happens, or I might even download the big file
> if this problem proves to be very elusive..
> 

I'll definitely do what I can to assist. I'll mess around with dd some 
more and see what I can come up with. If I can find a smaller clip I'll 
compile from cvs and see if your recent patch changes anything.

 > I looked at it and this clip is very strange. probably the motion is
 > so tiny and so aliased that pullup is getting confused about which
 > fields match better..

Interesting... I just checked and the sets of duplicate frames 
correspond perfectly with the text fading in the distance.

Roughly:
820 - 950 -- "Star Wars" fades
2221 - 2400 -- the first paragraph fades
2500 - 2700 -- the rest fades

Thanks,
Corey