title: Using multiprocessing with the PIL
body: <p>I have some code that does (independent) operations on a bunch of Python Imaging Library (PIL) Image objects. I would like to try and speed this up using parallel processing, so I read up on the multiprocessing module below:</p>
  
  <p><a href="http://docs.python.org/library/multiprocessing.html" rel="nofollow">http://docs.python.org/library/multiprocessing.html</a></p>
  
  <p>But it's still not very clear to me how to use multiprocessing for this problem.</p>
  
  <p>Conceptually, it looks like I could use a multiprocessing.Queue of Image objects and use a Pool of workers. But the Image objects seem 'unpickelable':</p>
  
  <pre><code>UnpickleableError: Cannot pickle &lt;type 'ImagingCore'&gt; objects
  </code></pre>
  
  <p>Is there a better way to process PIL images in parallel? </p>