title: ffmpeg webm vs mp4 quality issue
body: <p>I have a series of <code>.jpg</code> files in a directory that I want to turn into the movie with <code>ffmpeg</code>.  When I make a <code>.mp4</code> file of all the jpegs, the video quality is pretty much the same as the original images.  When I make a <code>.webm</code> file though, it looks very blocky.  These are the two commands I'm using:</p>
  
  <pre><code>$ ffmpeg -i %10d.jpg -s 640x480 -r 16 test.mp4
  
  $ ffmpeg -i %10d.jpg -s 640x480 -r 16 test.webm
  </code></pre>
  
  <p>I know next to nothing about video encoding so any help would be appreciated.</p>