loudness

#!/bin/bash

show_help() {
echo 'Usage: loudness scan [OPTION] [FILE]

`loudness` scans audio files according to the EBU R128 standard. It can output loudness and peak information.
This is a wrapper for ebur128 from the ebumeter debian package using ffmpeg to decompress the file temporarly before scanning.

Main operation mode:
  scan                       Output loudness and peak information.

Global options:
  -h, --help                 Display this text.
  --lufs                     Use absolute units. Default
  --full                     Print internal values as well.
  --prob                     Write cumulative probability file.
'
exit
}
if [ $# -lt 2 ]; then
	show_help
fi
if [ "$1" == "scan" ]; then
	case "$2" in
	-h)	show_help
		;;
	--help)	show_help
		;;
	--full)	opts="--full"
		;;
	--prob)	opts="--prob"
		;;
	--lufs)	opts="--lufs"
		;;
	*)	opts="compat" 
		;;
	esac
	if [ $# -eq 3 ]; then
		shift 1
	fi
	if [ -z "$(which ffmpeg)" ]; then
		echo "Error: ffmpeg binary not found!"
		exit 1
	fi
	if [ -z "$(which ebur128)" ]; then
		echo "Error: ebur128 binary not found!"
		exit 1
	fi
	filename="`basename \"$2\"`"
	tempdir="`mktemp -d`"
	ffmpeg-progress "$2" "$tempdir/test.wav" 1>&2 
	if [ -e "$tempdir/test.wav" ]; then
		if [ $opts = "compat" ]; then
			loudness="`ebur128 --lufs \"$tempdir/test.wav\" | head -n 1 | cut -d':' -f2 | sed 's/^ *//'`"
			echo -e "$loudness, $filename\n$loudness"
		else
			loudness="`ebur128 $opts \"$tempdir/test.wav\"`"
			echo -e "$filename\n$loudness"
		fi
	fi
	rm -rf $tempdir 1>/dev/null 2>&1
else
	show_help
fi