title: ffmpeg settings for converting to mp4 from ogg for HTML5 video
body: <p>I'm trying to convert OVG to MP4 H.264 valid format for use in HTML5 video.
  I tryid this:</p>
  
  <pre><code>ffmpeg -i video_source_file.ogv -vcodec libx264 -vpre ipod640 -b 250k -bt 50k -acodec libfaac -ab 56k -ac 2 -s 480x320 video_out_file.mp4
  </code></pre>
  
  <p>But the generated format is invalid for Internet Explorer 9 and 10. Other H.264 videos works fine. VLC says that the generated video is H.264.</p>
  
  <p>It only happens when I try to convert ogv/ogg valid videos to mp4 H.264.</p>
  
  <p>I also tried many options in ffmpeg2theora, but it appears only to convert files to theora. I thought this might help, but I could not generate a valid H.264.</p>
  
  <p>How to make it work?</p>