[MPlayer-users] Re: trying to convert MJPEG

[John Brown]

Steve Kleene <skmpl <at> syrano.acb.uc.edu> writes:

[cut]
>  The commands I had intended to test are:
> 
> mencoder lizard.avi \
>   -oac twolame -twolameopts br=192 -srate 48000 -af lavcresample=48000 \
>   -ovc lavc -lavcopts vcodec=mpeg1video:vbitrate=1000:mbd=2:trell:vpass=1 \
>   -of rawvideo \
>   -o /dev/null
> 
> mencoder lizard.avi \
>   -oac twolame -twolameopts br=192 -srate 48000 -af lavcresample=48000 \
>   -ovc lavc -lavcopts vcodec=mpeg1video:vbitrate=1000:mbd=2:trell:vpass=2 \
>   -of lavf -lavfopts
format=mpg:i_certify_that_my_video_stream_does_not_use_b_frames \
>   -o lizard.mpg
> 
> I just tested these and got a file that still failed on XP.  The audio was
> fine.  There was video, but it was very defective (blotches of color all
> over).

You certify_that_your_video_stream_does_not_use_b_frames. Do you know if that is
really true? Instead of -of lavf -lavfopts try:

-of mpeg -mpegopts format=mpeg1
> 
> With one difference, I have been using the commands shown above successfully
> to rip files from DVD to MPEG, and they play fine on XP.  The one difference
> is that the second lines read just "-oac twolame".

>  I don't understand why
> the commands above (modified for audio parameters supported by twolame) don't
> work to convert the avi file (from an older video camera) to MPEG.

Perhaps the DVD audio sample rate (48000) and bitrate are acceptable to twolame,
but the video camera's (11025) is not, and has to be resampled.