[MEncoder-users] Garbled sound while transcoding a video

[James Hastings-Trew]

Akshat Aranya wrote:
> Hi,
>
> I'm trying to use mencoder on Ubuntu Feisty to transcode videos. The
> video gets transformed OK but the audio is completely garbled. This
> happens no matter what kind of audio output I choose -- I've tried
> faac and mp3lame. The only way the audio is okay is if I just use the
> "-oac copy" option. Also, it does not matter what kind of video I try
> to transcode. Here's the command line that I'm using:
>
> mencoder a.avi -o b.avi -srate 44100 -oac mp3lame -lameopts
> vbr=0;br=96 -ovc lavc -lavcopts vcodec:mpeg4:vbitrate=96 -vf-add crop
> 586:352 -vf=add scale=240:144 -ofps 12.5 -ffourcc DIVX -noidx
> -force-avi-aspect 1.66666
Try this:
-af lavcresample=44100 -oac mp3lame -lameopts br=96:cbr

You can also put all of your video filters into one statement:
-vf crop=586:352,scale=240:144

Also, I am unsure why you want the -noidx option for your avi. Avi files 
without indexes are broken for a lot of applications. Perhaps you really 
want the -noodml option instead?

I could be wrong on this one, but I am under the impression that AVI 
headers do not store aspect ratio information (says so in the MEncoder 
docs in section 13.10) since the PAR of an AVI is always assumed to be 1:1.

One question though - why such ridiculously low bitrates for video?