title: ImageMagick `convert -composite` working on some, not on others
body: <p><strong>The problem</strong></p>
  
  <p>I'm running a convert command on a bunch of different images. Mostly, it's working just fine, but I noticed that a couple of images weren't being watermarked, as if the <code>-composite</code> command wasn't even there.</p>
  
  <p><strong>The command</strong></p>
  
  <pre><code>convert src.jpg -colorspace RGB -resize 1500x1500\&gt; -strip watermark.png -composite out.jpg
  </code></pre>
  
  <p>The <code>-colorspace</code>, <code>-resize</code>, and <code>-strip</code> commands are not really necessary in this test. But I get the same results if I remove them:</p>
  
  <pre><code>convert src.jpg watermark.png -composite out.jpg
  </code></pre>
  
  <p><strong>The image files</strong></p>
  
  <p><a href="http://files.mattalexander.me/imtest.zip" rel="nofollow">http://files.mattalexander.me/imtest.zip</a></p>
  
  <pre><code>*** ~: unzip -l imtest.zip
  Archive:  imtest.zip
    Length      Date    Time    Name
  ---------  ---------- -----   ----
          0  2010-11-13 18:54   imtest/
      22676  2010-11-18 11:12   imtest/out.jpg
         48  2010-11-13 18:54   imtest/run
      23293  2010-11-13 18:47   imtest/src.jpg
      76232  2010-11-13 18:47   imtest/watermark.png
  ---------                     -------
     122249                     5 files
  </code></pre>
  
  <p><strong>Software versions</strong></p>
  
  <p>Server #1</p>
  
  <pre><code>*** ~: cat /etc/issue
  Ubuntu 9.10 \n \l
  *** ~: uname -a
  Linux *** 2.6.31-22-server #67-Ubuntu SMP Sat Oct 16 19:03:54 UTC 2010 x86_64     GNU/Linux
  *** ~: convert --version
  Version: ImageMagick 6.5.1-0 2009-08-27 Q16 OpenMP http://www.imagemagick.org
  Copyright: Copyright (C) 1999-2009 ImageMagick Studio LLC
  </code></pre>
  
  <p>Server #2</p>
  
  <pre><code>*** ~: cat /etc/issue
  CentOS release 5.5 (Final)
  Kernel \r on an \m
  *** ~: uname -a
  Linux *** 2.6.18-194.8.1.el5.028stab070.5 #1 SMP Fri Sep 17 19:10:36     MSD 2010 i686 i686 i386 GNU/Linux
  *** ~: convert --version
  Version: ImageMagick 6.2.8 10/20/10 Q16 file:/usr/share/ImageMagick-6.2.8/doc/index.html
  Copyright: Copyright (C) 1999-2006 ImageMagick Studio LLC
  </code></pre>