[MEncoder-users] Re: Converting wmv3 to flv

[Scott]

RC <rcooley <at> spamcop.net> writes:
 
> > -lavcopts vcodec=flv:vbitrate=250:autoaspect:acodec=mp3:
> 
> lavc mp3 just calls lame, so you're better off using -oac mp3lame
> directly instead.  Perhaps then it won't crash with 2ch audio.

I tried this but mencoder still crashes.  I actually noticed that it
wasn't the 2ch audio that was causing the problem.  I had a couple
2ch files work today, so I'm not entirely sure what the problem is
with some wmv3 files that causes mencoder to seg fault.
 
> > This works pretty well, but the audio is slightly out of sync with 
> > the video.
> 
> You can always try -mc 0 / -mc 0.01 / -mc 10 / etc. 

That actually worked pretty well for a couple files, but for others it
completely ruined the av sync.  This is so discouraging.  I just wish
there was one way to do this that would work for every file.

> 
> > mencoder movie.flv -ovc copy -oac copy -audiofile audiodump.mp3
> >  -o movie2.flv
> 
> Without "-of lavf" you're just encoding to an AVI file.

I've created a new command for this, but I get a Floating point exception
now.  Here's what I'm trying:

mencoder movie.flv -o movie2.flv -of lavf -ovc lavc -oac copy 
-lavcopts vcodec=flv -audiofile audio.mp3 -mc 0

I did get this to work for one file, but this other one just doesn't want
to do it.  I created movie.flv with this command:

mencoder movie.wmv -o movie.flv -of lavf -ovc lavc -oac lavc
-lavcopts vcodec=flv:vbitrate=250:autoaspect:mbd=2:mv0:trell:v4mv:cbp
:last_pred=3:predia=2:dia=2:precmp=2:cmp=2:subcmp=2:preme=2:turbo 
-vf scale=400:300 -nosound -ofps 15

I'm not sure if I should use -oac lavc or -oac copy in this case.  It may
not even matter because I'm using -nosound.  This does eliminate the
seg fault I mentioned above at least, but the resulting file is without
sound.

I've had one success case in all my tests, but now the floating point
exception is a real hurdle.

> > I think with mplayer I have to wait out the entire duration of the
> > video to get the  audiodump which is too long.
> 
> Nope.  Look at the output of mplayer when using "-ao pcm", it tells you
> how to speed-up audio output, using "-vc dummy" and a few other
> options.

-vc dummy worked great and I can now extract audio much quicker.


Thank you!
- Scott