encode with two sound tracks, and normalize mencoder and ffmpeg

#!/bin/sh
echo "***********************************************************"
echo  titre 4
echo "***********************************************************"

nice -19  mencoder dvd://4 -dvd-device /home/fabien/dora_dvd/ -o francais.mp3 -of rawaudio -ovc frameno -aid 129 -oac mp3lame -lameopts preset=96,aq=2 -af volnorm=1

nice -19  mencoder dvd://4 -dvd-device /home/fabien/dora_dvd/ -o anglais.mp3 -of rawaudio -ovc frameno -aid 128 -oac mp3lame -lameopts preset=96,aq=2 -af volnorm=1


nice -19 mencoder dvd://4 -dvd-device /home/fabien/dora_dvd  -sid 0  -nosound -ovc lavc -lavcopts vcodec=mpeg4:vhq:v4mv:vqmin=2:vbitrate=1093:vpass=1 -vf pp=de,crop=704:576:10:0    -o /dev/null
nice -19 mencoder dvd://4 -dvd-device /home/fabien/dora_dvd -sid 0 -nosound -ovc lavc -lavcopts vcodec=mpeg4:vhq:v4mv:vqmin=2:vbitrate=1093:vpass=2 -vf pp=de,crop=704:576:10:0    -o "/home/fabien/doratmp.avi"

nice -19 ffmpeg -i doratmp.avi -vcodec copy  -i francais.mp3 -acodec copy -i anglais.mp3 -y dora4.avi -acodec copy -newaudio

unlink doratmp.avi 2> /dev/null
unlink francais.mp3 2> /dev/null
unlink anglais.mp3 2> /dev/null