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If the image already has a colormap, it is replaced. AcquireImageColormap() returns MagickTrue if successful, otherwise MagickFalse if there is not enough memory.</p> 60 61<p>The format of the AcquireImageColormap method is:</p> 62 63<pre class="text"> 64MagickBooleanType AcquireImageColormap(Image *image,const size_t colors, 65 ExceptionInfo *exception) 66</pre> 67 68<p>A description of each parameter follows:</p> 69 70<dd> 71</dd> 72 73<dd> </dd> 74<dl class="dl-horizontal"> 75<dt>image</dt> 76<dd>the image. </dd> 77 78<dd> </dd> 79<dt>colors</dt> 80<dd>the number of colors in the image colormap. </dd> 81 82<dd> </dd> 83<dt>exception</dt> 84<dd>return any errors or warnings in this structure. </dd> 85 86<dd> </dd> 87</dl> 88<h2><a href="http://nextgen.imagemagick.org/api/MagickCore/colormap_8c.html" id="CycleColormap">CycleColormap</a></h2> 89 90<p>CycleColormap() displaces an image's colormap by a given number of positions. If you cycle the colormap a number of times you can produce a psychodelic effect.</p> 91 92<p>WARNING: this assumes an images colormap is in a well know and defined order. Currently Imagemagick has no way of setting that order.</p> 93 94<p>The format of the CycleColormapImage method is:</p> 95 96<pre class="text"> 97MagickBooleanType CycleColormapImage(Image *image,const ssize_t displace, 98 ExceptionInfo *exception) 99</pre> 100 101<p>A description of each parameter follows:</p> 102 103<dd> 104</dd> 105 106<dd> </dd> 107<dl class="dl-horizontal"> 108<dt>image</dt> 109<dd>the image. </dd> 110 111<dd> </dd> 112<dt>displace</dt> 113<dd> displace the colormap this amount. </dd> 114 115<dd> </dd> 116<dt>exception</dt> 117<dd>return any errors or warnings in this structure. </dd> 118 119<dd> </dd> 120</dl> 121</div> 122 <footer class="magick-footer"> 123 <p><a href="../script/support.php">Donate</a> • 124 <a href="../script/sitemap.php">Sitemap</a> • 125 <a href="../script/links.php">Related</a> • 126 <a href="../script/architecture.php">Architecture</a> 127</p> 128 <p><a href="colormap.php#">Back to top</a> • 129 <a href="http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x89AB63D48277377A">Public Key</a> • 130 <a href="../script/contact.php">Contact Us</a></p> 131 <p><small>© 1999-2016 ImageMagick Studio LLC</small></p> 132 </footer> 133</div><!-- /.container --> 134 135 <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.3/jquery.min.js"></script> 136 <script src="http://nextgen.imagemagick.org/js/magick.php"></script> 137</div> 138</body> 139</html> 140