Mencoder // ffmpeg flv file Audio-video sync problem

[krishnareddy]

I have installed MENCODER, FLVTOOLS2 and FFMPEG on my dedicated linux redhat server.

When i convert any files( say AVI) to FLV format ... some how the Video is faster than the audio.

I use the following to convert AVI file to FLV file.

mencoder ./Screenshots.avi -o test222.flv -of lavf -oac mp3lame -lameopts abr:br=56  -ovc lavc -lavcopts  vcodec=flv:vbitrate=400:mbd=2:mv0:trell:v4mv:cbp:last_pred=3 -of lavf -lavfopts format=flv -srate 22050

Can anyone help me what i should do ?

NOTE: VIDEO is very fast ... compared to AUDIO. This is my problem. I want proper sync.

Your help is highly appreciated

[tomlee59]

This is the ffmpegx forum, which is not exactly the same thing (it's a gui wrapper for ffmpeg and other tools). And it's been a very long time since I used ffmpeg, so this is a guess: Your command line doesn't include any info about framerate. From the description of your problem, it is apparently the source of your problem. So, find the frame rate of your source, and make sure that you convert to same. At minimum, you'll need to add a switch like "-ofps 24000/1001" or some such thing (replace 24000/1001 by the desired output framerate).

I'm sure others with more experience with ffmpeg will chime in with better advice shortly.

[krishnareddy]

Hi, thanks for your reply.

I have tried using your suggestion as follows.

mencoder ./Screenshots.avi -o test333.flv -of lavf -oac mp3lame -lameopts abr:br=56  -ovc lavc -lavcopts  vcodec=flv:vbitrate=400:mbd=2:mv0:trell:v4mv:cbp:last_pred=3 -of lavf -lavfopts format=flv -srate 22050 -ofps 24000/1001

BUT it does not help in anyway. The video is so fast and audio is normal - same as before

[krishnareddy]

Can any one help with this ?

[Case]

ffmpegX (the Mac GUI app) uses ffmpeg for FLV encodings, not mencoder. I suppose the developer did that for a reason.

[Case]

ffmpeg -i source.avi -y -map 0.0:0.0 -f flv -vcodec flv -b 400 -aspect 4:3 -s 320x240 -r ntsc-film -g 240 -me epzs -qmin 2 -qmax 15 -acodec mp3 -ab 56 -ar 22050 -ac 2  -map 0.1:0.1 -benchmark target.flv

flvtool2 -UP target.flv