3 # Many DVDs released in Australia are sped up from 24fps to 25fps.
4 # This script reverses the procedure, correcting the audio pitch.
5 # The video framerate is adjusted without re-encoding. The audio is
6 # slowed, volume normalised, down-mixed to stereo and encoded as mp3.
8 if [ -z "$1" -o -z "$2" ]; then
9 echo "Usage: $0 destdir infile [infile ...]"
17 function mux_replace_audio
{
22 trackid
="$(mkvmerge -i "$infile" | grep video | sed 's/^Track ID \(.\):.*$/\1/')"
23 mkvmerge
-o "${outfile}" --default-duration "${trackid}:${FORCEFPS}fps" --no-audio "$infile" "$audiofile"
26 function extract_audio
{
32 --ao pcm
:waveheader
:file=/dev
/stdout \
46 function encode_audio
{
54 function convert_file
{
57 tmpdir
="$(mktemp -d "${TMPDIR:-/var/tmp}/pal-XXXXXXXX
")"
58 audiofile
="${tmpdir}/audio.mp3"
60 extract_audio
"${infile}" | slow_audio | encode_audio
"${audiofile}"
61 mux_replace_audio
"${infile}" "${audiofile}" "${outfile}"
70 for infile
in "$@"; do
71 outfile
="$destdir/$(basename "$infile")"
73 if [ -f "$outfile" ]; then
74 echo "Not overwriting $outfile"
78 convert_file
"$infile" "$outfile"