#!/bin/bash

if [ -z "$1" ]; then
	echo "Usage: $0 dvd-device"
	exit 1
fi

mplayer 2> /dev/null \
	-quiet -ao null -vo null -frames 0 -identify -dvd-device "$1" dvd:// | \
	grep 'ID_DVD_TITLE_[0-9]*_LENGTH'