title: How to set a fixed width, maximum height using sorl-thumbnail (in Django)
body: <p>I can't work out if it's possible to create the following thumbnail using sorl-thumbnail in a django template:</p>
  
  <ul>
  <li>Fixed width, upscaled if necessary.</li>
  <li>Maximum height.  If the resized image is shorter than the max height than I don't mind.</li>
  <li>I don't want to crop the image width-wise but I don't mind cropping it height-wise.</li>
  </ul>
  
  <p>If I were able to do this in two steps, I would:</p>
  
  <ul>
  <li>Resize the image to x width, allowing upscaling.</li>
  <li>Crop the image to fit within a rectangle x by y.</li>
  </ul>
  
  <p>The best I can do is this, which gets the width looking good but doesn't crop the height.</p>
  
  <pre><code>{% thumbnail banner "1010" crop="center" as im %}&lt;img id='banner' src='{{ im.url }}'/&gt;{% endthumbnail %}
  </code></pre>
  
  <p>Any ideas?</p>