title: AVURLAsset getting video size
body: <p>This is pretty frustrating. I'm trying to get the size of an AVURLasset, but try to avoid <code>naturalSize</code> since Xcode tells me, this is deprecated in iOS5. </p>
  
  <p>But: What's the replacement?</p>
  
  <p>I can't find any clue on how to get the video-dimensions without using «naturalsize»...</p>