title: Imagick+php UnableToOpenBlob with mp4 file
body: <p>I'm trying to make a simple Imagick operation on my local environment, like</p>
  
  <pre><code>$im = new Imagick("File.mp4[100]");
  </code></pre>
  
  <p>to prepare video file frame capture. Unfortunately I get a strange exception:</p>
  
  <blockquote>
    <p>UnableToOpenBlob `C:/Temp/magick-5924U7hGfaatgEtF.pam': No such file or directory @ error/blob.c/OpenBlob/2657</p>
  </blockquote>
  
  <p>I've made C:\Temp directory fully writable to "Everybody" - nothing changes.</p>
  
  <p>When I'm running <code>convert File.mp4[100] File.jpg</code> from command line operation succeeds, JPG file is generated.</p>
  
  <p>My environment:
  PHP Version 5.6.12
  Imagick module version  3.1.2
  ImageMagick version     ImageMagick 6.8.9-1 Q16 x86 2014-05-08 </p>