Reading the id3 length tag from a file

Is there any way I can read just the length from mp3 files?
I’ve been searching around, but only found things that are listing all id3 tags. I just want to grab the length of track.mp3

Sorry to reply with just a link (I’m on my iPad), however this should do what you need: http://www.zedwood.com/article/127/php-calculate-duration-of-mp3