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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">I would assume you could accomplish this with PerlMagick…<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">and a quick internet search reveals:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><a href="http://stackoverflow.com/questions/2350740/how-do-i-replace-any-color-that-is-not-a-specific-color-using-perlmagick">http://stackoverflow.com/questions/2350740/how-do-i-replace-any-color-that-is-not-a-specific-color-using-perlmagick</a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">The basic syntax is
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal">use Image::Magick;<o:p></o:p></p>
<p class="MsoNormal">my $image = Image::Magick->new;<o:p></o:p></p>
<p class="MsoNormal">$image->Read('x.gif');<o:p></o:p></p>
<p class="MsoNormal">$image->Opaque(fill =><span class="pln"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">
</span></span><span class="str">'black'</span><span class="pun">,</span><span class="pln"> color
</span><span class="pun">=></span><span class="pln"> </span><span class="str">'red'</span><span class="pun">);</span><span class="pln"><o:p></o:p></span></p>
<p class="MsoNormal"><span class="pln">$image</span><span class="pun">-></span><span class="typ">Write</span><span class="pun">(</span><span style="font-size:10.0pt;font-family:"Courier New"">'</span>x_changed.gif<span class="str">'</span><span class="pun">);</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><a name="_MailEndCompose"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Robert Flach<o:p></o:p></span></a></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> Dfw-pm [mailto:dfw-pm-bounces+rflach=hrsmart.com@pm.org]
<b>On Behalf Of </b>Jerry Kassebaum<br>
<b>Sent:</b> Saturday, January 5, 2013 7:29 PM<br>
<b>To:</b> dfw-pm@pm.org<br>
<b>Subject:</b> [DFW.pm] Changing colors in a gif using cgi<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">How do I change colors in a gif using cgi or perl? In other words how do I read a file in binary or hex, change some bits or bytes, and write it back?<br>
<br>
A very simple file is attached if you want to use it.<br>
<br>
My long-term goal is to start with all black, then blacken every color except, say, a00000 to afffff, then everything except, say, 200000 to 2fffff AND a00000 to afffff, etc., until the user can guess what the picture is.<br>
<br>
Jerry Kassebaum<o:p></o:p></span></p>
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