#!/bin/bash

# Determine the length of a media file by playing it.
#
# mplayer's AUDIO lines look like this:
# AUDIO: 44100 Hz, 2 ch, s16le, 128.0 kbit/9.07% (ratio: 16000->176400)

printrate=0
while getopts r opt;do
 case $opt in
  r)    printrate=1;;
 esac
done
shift `expr $OPTIND - 1`

for file; do
	
	mplayer -vo null -vc dummy -ao pcm:waveheader:file=>(
			wc -c |sed 's/^/WAVESIZE: /'
		) "$file" </dev/null 2>&1 |
	{ awk '/^AUDIO: [0-9]+ Hz/ {
			rate=$2
			channels=$4;
			bitspersample=gensub("[^0-9]","","g",$6);  }
	     /^WAVESIZE: [0-9]+/ { wavesize=$2 }
	     END {
			OFMT="%f"
			if ('"$printrate"') { printf "%s ", rate }
			print 8 * wavesize / ( rate * channels * bitspersample ) }'
	  echo "$file";
	} | paste - -
done