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Code:
/usr/bin/mencoder '/home/leedsplt/public_html/video/skateboard_trick.wmv' -o /home/leedsplt/public_html/flvideo/11946002111122988016.flv -of lavf -oac mp3lame -lameopts abr:br=56 -ovc lavc -lavcopts vcodec=flv:vbitrate=500:mbd=2:mv0:trell:v4mv:cbp:last_pred=3 -srate 22050 -ofps 24 -vf harddup
See FAQ

Video Not Playing
Video not getting converted to flv