title: How to extract key frames from video?
body: <p>I need to extract all <a href="http://en.wikipedia.org/wiki/Video_compression_picture_types" rel="nofollow">keyframes (I-frames)</a> from mp4-video as array of <a href="http://msdn.microsoft.com/ru-ru/library/system.drawing.bitmap.aspx" rel="nofollow">Bitmaps</a>.</p>
  
  <p>I've tryed different ffmpeg wrappers: <a href="http://ffmpegdotnet.codeplex.com/" rel="nofollow">FFMpeg.NET</a>, <a href="http://code.google.com/p/ffmpeg-sharp/" rel="nofollow">FFMpeg-Sharp</a>, <a href="http://www.intuitive.sk/fflib/" rel="nofollow">FFLib.NET</a>. But all of this projects work only under Windows (maybe I'm wrong, but I can't compile it under my linux machine).</p>
  
  <p>So, how can I solve this problem under linux with Mono?</p>