title: How do I set the interlaced flag on an MKV file so that VLC can automatically play it back deinterlaced?
body: <p>I've got an MKV file whose source is interlaced NTSC MPEG-2 video. I converted it to H.264 MKV with HandBrake, but this process did not set the "interlaced" flag in the MKV file.  The content <em>is</em> interlaced—and I do want it to stay interlaced because it looks much better playing back as 60 fields-per-second content with on-the-fly deinterlacing than it does as 30 frames-per-second content that's been deinterlaced at encode-time.</p>
  
  <p>I tried this...</p>
  
  <pre><code>mkvpropedit -e track:v1 -a interlaced=1 foo.mkv
  </code></pre>
  
  <p>which <em>did</em> indeed set the interlaced bit...</p>
  
  <pre><code>|+ Segment tracks
  | + A track
  |  + Video track
  |   + Pixel width: 704
  |   + Pixel height: 480
  |   + Display width: 625
  |   + Display height: 480
  |   + Interlaced: 1
  </code></pre>
  
  <p>But when I play the video with VLC with Deinterlace set to Automatic, it doesn't think the video is interlaced and therefore doesn't do the deinterlacing.</p>
  
  <p>What am I doing wrong?</p>
  
  <p>Software versions:<br>
  HandBrake 0.9.5<br>
  mkvpropedit v5.0.1<br>
  Mac OS X 10.7.3</p>