title: Converting SVG to another format fail due to delegate not being found
body: <p>I have PHP code running on Debian stretch with ImageMagick. It tries to convert SVG to another format. Here is how it starts</p>
  
  <pre><code>$im = new Imagick();
  $im-&gt;readImageBlob($svg);
  </code></pre>
  
  <p>The variable <code>$svg</code> contains valid SVG code in a string. If I copy this string to a text file with a <code>.svg</code> extension then it opens just fine. But <code>readImageBlob</code> throws an exception saying <code>no delegate for this image format</code>.</p>
  
  <p>I have seen similar questions solved by installing more packages to the system. But I've already installed <code>libxml2-dev</code>, <code>librsvg2-bin</code>, <code>libmagickcore-6.q16-3-extra</code> and <code>libfreetype6-dev</code>.</p>
  
  <p>I have no idea what else I am missing.</p>