从视频中提取一个声道并重新封装，解决部分视屏只有左边声音的问题

conv.sh

#!/bin/sh

############
# require:
# - ffmpeg
# - faad
# - sox
############

aac="audio.aac"
wav="audio.wav"
outl="outl.wav"
video="video.avi"
left="1"
right="2"
raw_video=$1


extra_video() {
    echo -e "ffmpeg -i $raw_video -vcodec copy -an $video\n\n"
    ffmpeg -i $raw_video -vcodec copy -an $video
}

extra_audio() {
    echo -e "ffmpeg -i $raw_video -acodec copy -vn $aac\n\n"
    ffmpeg -i $raw_video -acodec copy -vn $aac
}

convert_aac_to_wav() {
    echo -e "faad -o $wav $aac\n"
    faad -o $wav $aac
}

split_left_channel() {
    echo -e "sox $wav $outl remix $left\n"
    sox $wav $outl remix $left
}

package_to_mp4() {
    ffmpeg -i $outl -i $video -vcodec copy -strict -2 -acodec aac $raw_video
}

clean_up() {
    rm -f $aac $wav $outl $video
}

main() {
    extra_video
    extra_audio
    convert_aac_to_wav
    split_left_channel
    package_to_mp4
    clean_up
}
main
#!/bin/sh

aac="audio.aac"
wav="audio.wav"
outl="outl.wav"
video="video.avi"
left="1"
right="2"
raw_video=$1


extra_video() {
    echo -e "ffmpeg -i $raw_video -vcodec copy -an $video\n\n"
    ffmpeg -i $raw_video -vcodec copy -an $video
}

extra_audio() {
    echo -e "ffmpeg -i $raw_video -acodec copy -vn $aac\n\n"
    ffmpeg -i $raw_video -acodec copy -vn $aac
}

convert_aac_to_wav() {
    echo -e "faad -o $wav $aac\n"
    faad -o $wav $aac
}

split_left_channel() {
    echo -e "sox $wav $outl remix $left\n"
    sox $wav $outl remix $left
}

package_to_mp4() {
    ffmpeg -i $outl -i $video -vcodec copy -strict -2 -acodec aac $raw_video
}

clean_up() {
    rm -f $aac $wav $outl $video
}

main() {
    extra_video
    extra_audio
    convert_aac_to_wav
    split_left_channel
    package_to_mp4
    clean_up
}
main