title: Reading video file metadata with ruby
body: <p>I am working on a app and I let users to upload videos.
  The problem is I need to get the width and height of the videos after users submitted the form, but couldn't find a way to do it.</p>
  
  <p>Users can upload any video type, avi, mpeg, mov, flv..</p>
  
  <p>I just need to get width and height metadata of the video, but so far I couldn't find a ruby function or a gem.</p>
  
  <p>thanks.</p>