title: Get aplitude curve from audio
body: <p>I am using libmpg123 library for parsing and decoding mp3 song, but I want draw something like this:
  <a href="http://img.photobucket.com/albums/v627/Flabbergast/jurafirstCDpressing-1.jpg" rel="nofollow">http://img.photobucket.com/albums/v627/Flabbergast/jurafirstCDpressing-1.jpg</a></p>
  
  <p>How can I get an amplitude from mp3 song? I am trying to find solution in a lot of pages but without good result.
  Thanks for your answer</p>