#!/bin/bash

SourceFile="$1"
if [ ! -r "$SourceFile" ] ; then
    echo "Usage: $0 <image> [<lameopts>]"
    exit 1
fi

BaseName="$(basename "$SourceFile" | sed 's/\(.*\)\..*/\1/')"
Original="$BaseName.original.png"

if [ ! -r "$Original" ] ; then
    echo "making $Original ..."
    convert "$SourceFile" -colorspace gray "$Original" || exit 1
else
    echo "using the existing version of $Original"
fi

Dimensions="$(identify "$Original" | tr ' ' '\n' | egrep '[0-9]+x[0-9]+' | head -1 | tr x ' ')"
convert "$Original" mp3img.gray || exit 1

shift
BaseName="$BaseName.$(tr -d ' \n\t\v' <<< "$*")"
lame -r -s 24 --resample 24 --bitwidth 8 -m m $* mp3img.gray "$BaseName.mp3" || exit 1
lame --decode -x -t "$BaseName.mp3" mp3img.gray || exit 1
python -c "import sys;sys.stdout.write('P5\n$Dimensions\n255\n'+''.join([chr((ord(c)+128)&255) for c in sys.stdin.read()[::2]]))" <mp3img.gray >mp3img.pgm
convert mp3img.pgm "$BaseName.png" || exit 1
rm -f mp3img.{gray,pgm}