title: ImageMagick convert pdf to jpeg has poor text quality after upgrading ImageMagick version to 6.7.8
body: <p>After upgrading <code>ImageMagick</code> text quality got degraded when convert pdf to jpeg:</p>
  
  <p><strong>Old image</strong>
  <img src="https://i.stack.imgur.com/90lQg.jpg" alt="enter image description here"></p>
  
  <p><strong>New Image</strong>
  <img src="https://i.stack.imgur.com/Lh5Mt.jpg" alt="enter image description here">
  Conversion command: <code>convert foo.pdf foo.jpeg</code></p>
  
  <p><strong>Old ImageMagick version:</strong></p>
  
  <pre><code>[root@home]#  convert -version
  Version: ImageMagick 6.2.8 05/07/12 Q16 file:/usr/share/ImageMagick-6.2.8/doc/index.html
  Copyright: Copyright (C) 1999-2006 ImageMagick Studio LLC
  </code></pre>
  
  <p>generated files size:</p>
  
  <pre><code>-rw-r--r-- 1 root root 139K Apr  2 16:11 foo-0.jpeg
  -rw-r--r-- 1 root root 130K Apr  2 16:11 foo-1.jpeg
  -rw-r--r-- 1 root root 334K Mar 24 14:27 foo.pdf
  </code></pre>
  
  <p><strong>After upgrading ImageMagick</strong></p>
  
  <pre><code>[root@home]#  convert -version
  Version: ImageMagick 6.7.8-10 2012-08-17 Q16 http://www.imagemagick.org
  Copyright: Copyright (C) 1999-2012 ImageMagick Studio LLC
  Features: OpenMP
  </code></pre>
  
  <p>generated files size:</p>
  
  <pre><code>-rw-r--r-- 1 root root  60K Apr  2 16:11 foo-0.jpeg
  -rw-r--r-- 1 root root  55K Apr  2 16:11 foo-1.jpeg
  -rw-r--r-- 1 root root 334K Mar 24 14:27 foo.pdf
  </code></pre>
  
  <p>I've tried using <a href="http://www.imagemagick.org/script/command-line-options.php#antialias" rel="noreferrer"><code>antialias</code></a> flag:</p>
  
  <pre><code>convert -antialias  foo.pdf foo.jpeg
  </code></pre>
  
  <p>Which did nothing, I've tried setting an higher <a href="http://www.imagemagick.org/script/command-line-options.php#quality" rel="noreferrer"><code>quality</code></a>:</p>
  
  <pre><code>convert -quality 100 foo.pdf foo.jpeg
  </code></pre>
  
  <p>and <a href="http://www.imagemagick.org/discourse-server/viewtopic.php?f=6&amp;t=17658" rel="noreferrer">super sampling</a>:</p>
  
  <pre><code>convert -density 288 -background white -alpha off foo.pdf -resize 25%  foo.jpeg
  </code></pre>
  
  <p>both gave bigger files and better results, but ran more time and had lower quality that the old ImageMagick version.</p>
  
  <p>any advises?</p>
  
  <h2><a href="https://docs.google.com/file/d/0B7lQLM2Zf1UDUDNHaVNFQ2lfV00/edit?usp=sharing" rel="noreferrer">Link to the file</a></h2>