#!/bin/bash

# Convert any video/audio stream that mplayer can play
# into a VCD-compatible Mpeg output file.
# Arguments: $1 - name of input
#            $2 - name of output

if [ $# -ne 2 ]; then
  echo "Usage:"
  echo "  tovcd <input file> <output prefix>"
  exit 1
fi

# Probe for width, height, and frame rate
tcprobe -i "$1" > fileinfo
WIDTH=`grep 'import frame size' fileinfo | \
  perl -e ' $line=<STDIN> ; $line =~ /import frame size: -g (\d+?)x\d+ /  ;  print $1' `
HEIGHT=`grep 'import frame size' fileinfo | \
  perl -e ' $line=<STDIN> ; $line =~ /import frame size: -g \d+?x(\d+) /  ;  print $1' `
FPS=`grep 'frame rate' fileinfo | \
  perl -e ' $line=<STDIN> ; $line =~ /frame rate: -f (.+?) \[/  ;  print $1' `

echo "Input file is $WIDTH x $HEIGHT at $FPS fps."

# If FPS is already 29.97 (NTSC) or 23.976 (NTSC film), leave it alone
if [[ $FPS == "29.970" ]];
then
  echo "Source is 29.970 fps (NTSC). Encoding as NTSC video."
  ADJUSTFPS=""
  ENCFPS="-F 4"
elif [[ $FPS == "23.976" ]];
then
  echo "Source is 23.976 fps (NTSC film). Encoding as NTSC film."
  ADJUSTFPS=""
  ENCFPS="-F 1"
else
  echo "Source is not at an NTSC frame rate. Adjusting FPS."
  ADJUSTFPS="yuvfps -r 30000:1001 -v 0 |"
  ENCFPS="-F 4"
fi

# If resolution is already 352x240, do not rescale
if [[ $WIDTH == "352" && $HEIGHT == "240" ]];
then
  echo "Source appears to be VCD resolution (352x240). No rescaling will be applied."
  ADJUSTSIZE=""
# See if source is VCD PAL (352x288) or (320x240)
# If so, just rescale; aspect ratio should be fine
elif [[ $WIDTH == "352" && $HEIGHT == "288" ]] || [[ $WIDTH == "320" && $HEIGHT == "240" ]];
then
  echo "Assuming a VCD PAL (352x288) or (320x240) correct 4:3 aspect ratio. Rescaling."
  ADJUSTSIZE="yuvscaler -O VCD -v 0 -n n |"
# Otherwise, assume a widescreen (16:9) aspect, and pad with black bars
else
  echo "Assuming source is widescreen (16:9) aspect ratio. Padding with black bars."
  ADJUSTSIZE="yuvscaler -O VCD -v 0 -n n -M WIDE2VCD |"
fi

echo "Creating and encoding video stream..."
mkfifo stream.yuv
mplayer -nosound -noframedrop -vo yuv4mpeg -vf pp=hb/vb/dr,hqdn3d "$1" &
eval `echo "cat stream.yuv | $ADJUSTFPS $ADJUSTSIZE nice -n 16 mpeg2enc -a 2 -f 1 $ENCFPS -v 0 -n n -H -o $2.m1v"`

echo "Creating WAV of audio stream..."
mplayer -vc dummy -vo null -ao pcm -aofile stream.wav "$1"
echo "Normalizing WAV audio..."
normalize --amplitude=-10dBFS stream.wav
echo "Encoding WAV..."
cat stream.wav | mp2enc -V -o "$2.mpa"

echo "Multiplexing audio and video together..."
tcmplex -i "$2.m1v" -p "$2.mpa" -o "$2.mpg" -m v

echo "Cleaning up..."
rm stream.yuv
rm stream.wav
rm "$2.m1v"
rm "$2.mpa"
rm fileinfo

echo "Done"