[MPlayer-users] Mencoder Audio Synchronization

[D Richard Felker III]

On Fri, Apr 23, 2004 at 11:28:21AM -0700, Herb Wartens wrote:
> Hi Everyone...
> I am using an AthlonXp 2100+
> with an Nvidia GeForce 4400
> on a Slackware-current box
> 
> Movies that I download from other sites
> and DVDs play fine on my machine
> However whenever I encode my own DIVX movies my audio is always out of synch
> with the video
> 
> Here is part of a small script that I wrote to encode videos:
> 
> ----------------------------------
> 
> rm -rf frameno.avi
> 
> # Encode Audio
> /usr/bin/nice -n 19 mencoder dvd://1 -ovc frameno -o frameno.avi -oac mp3lame
> -lameopts abr:br=160 -alang en
> 
> # Encode Video Pass 1
> /usr/bin/nice -n 19 mencoder dvd://1 -oac copy -o /dev/null -ovc lavc -lavcopts
> vcodec=mpeg4:vbitrate=1024:vhq:v4mv:trell:vpass=1:keyint=128 -ofps 23.976 -vf
> pp=fd,crop=720:358:0:58
> 
> # Encode Video Pass 2
> /usr/bin/nice -n 19 mencoder dvd://1 -oac copy -o final_movie.avi -ovc lavc
> -lavcopts vcodec=mpeg4:vbitrate=1024:vhq:v4mv:trell:vpass=2:keyint=128 -ofps
> 23.976 -vf pp=fd,crop=720:358:0:58
> 
> ----------------------------------
> 
> Can anyone tell me what is going on with this?  Can anyone tell me how to
> improve the encoding process so that my audio comes out properly in my movies? 
> Any help would be great...
> Thanks

Try getting rid of the frameno pass. It's known to be buggy and cause
a/v desync in some cases. At the very least, you need to use the same
-ofps for all three passes!

Rich