1 2 3 4 5<!doctype html> 6<html lang="en"> 7<head> 8 <meta charset="utf-8" /> 9 <meta name="viewport" content="width=device-width, initial-scale=1" /> 10 <title>ImageMagick - MagickCore, C API: Colormap Methods</title> 11 <meta name="application-name" content="ImageMagick" /> 12 <meta name="description" content="Use ImageMagick® to create, edit, compose, and convert digital images. 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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> 99 100<p>The format of the AcquireImageColormap method is:</p> 101 102<pre class="text"> 103MagickBooleanType AcquireImageColormap(Image *image,const size_t colors, 104 ExceptionInfo *exception) 105</pre> 106 107<p>A description of each parameter follows:</p> 108 109<dd> 110</dd> 111 112<dd> </dd> 113<dl class="dl-horizontal"> 114<dt>image</dt> 115<dd>the image. </dd> 116 117<dd> </dd> 118<dt>colors</dt> 119<dd>the number of colors in the image colormap. </dd> 120 121<dd> </dd> 122<dt>exception</dt> 123<dd>return any errors or warnings in this structure. </dd> 124 125<dd> </dd> 126</dl> 127<h2><a href="../../api/MagickCore/colormap_8c.html" id="CycleColormap">CycleColormap</a></h2> 128 129<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> 130 131<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> 132 133<p>The format of the CycleColormapImage method is:</p> 134 135<pre class="text"> 136MagickBooleanType CycleColormapImage(Image *image,const ssize_t displace, 137 ExceptionInfo *exception) 138</pre> 139 140<p>A description of each parameter follows:</p> 141 142<dd> 143</dd> 144 145<dd> </dd> 146<dl class="dl-horizontal"> 147<dt>image</dt> 148<dd>the image. </dd> 149 150<dd> </dd> 151<dt>displace</dt> 152<dd> displace the colormap this amount. </dd> 153 154<dd> </dd> 155<dt>exception</dt> 156<dd>return any errors or warnings in this structure. </dd> 157 158<dd> </dd> 159</dl> 160</div> 161 </div> 162 </main><!-- /.container --> 163 <footer class="magick-footer"> 164 <div class="container-fluid"> 165 <a href="../../www/security-policy.html">Security</a> • 166 <a href="../../www/news.html">News</a> 167 168 <a href="colormap.html#"><img class="d-inline" id="wand" alt="And Now a Touch of Magick" width="16" height="16" src="../../../images/wand.ico"/></a> 169 170 <a href="../../www/links.html">Related</a> • 171 <a href="../../www/sitemap.html">Sitemap</a> 172 <br/> 173 <a href="../../www/support.html">Sponsor</a> • 174 <a href="../../www/cite.html">Cite</a> • 175 <a href="http://pgp.mit.edu/pks/lookup?op=get&search=0x89AB63D48277377A">Public Key</a> • 176 <a href="../../www/contact.html">Contact Us</a> 177 <br/> 178 <a href="https://github.com/imagemagick/imagemagick" target="_blank" rel="noopener" aria-label="GitHub"><svg xmlns="http://www.w3.org/2000/svg" class="navbar-nav-svg" viewBox="0 0 512 499.36" width="2%" height="2%" role="img" focusable="false"><title>GitHub</title><path fill="currentColor" fill-rule="evenodd" d="M256 0C114.64 0 0 114.61 0 256c0 113.09 73.34 209 175.08 242.9 12.8 2.35 17.47-5.56 17.47-12.34 0-6.08-.22-22.18-.35-43.54-71.2 15.49-86.2-34.34-86.2-34.34-11.64-29.57-28.42-37.45-28.42-37.45-23.27-15.84 1.73-15.55 1.73-15.55 25.69 1.81 39.21 26.38 39.21 26.38 22.84 39.12 59.92 27.82 74.5 21.27 2.33-16.54 8.94-27.82 16.25-34.22-56.84-6.43-116.6-28.43-116.6-126.49 0-27.95 10-50.8 26.35-68.69-2.63-6.48-11.42-32.5 2.51-67.75 0 0 21.49-6.88 70.4 26.24a242.65 242.65 0 0 1 128.18 0c48.87-33.13 70.33-26.24 70.33-26.24 14 35.25 5.18 61.27 2.55 67.75 16.41 17.9 26.31 40.75 26.31 68.69 0 98.35-59.85 120-116.88 126.32 9.19 7.9 17.38 23.53 17.38 47.41 0 34.22-.31 61.83-.31 70.23 0 6.85 4.61 14.81 17.6 12.31C438.72 464.97 512 369.08 512 256.02 512 114.62 397.37 0 256 0z"/></svg></a> • 179 <a href="https://twitter.com/imagemagick" target="_blank" rel="noopener" aria-label="Twitter"><svg xmlns="http://www.w3.org/2000/svg" class="navbar-nav-svg" viewBox="0 0 512 416.32" width="2%" height="2%" role="img" focusable="false"><title>Twitter</title><path fill="currentColor" d="M160.83 416.32c193.2 0 298.92-160.22 298.92-298.92 0-4.51 0-9-.2-13.52A214 214 0 0 0 512 49.38a212.93 212.93 0 0 1-60.44 16.6 105.7 105.7 0 0 0 46.3-58.19 209 209 0 0 1-66.79 25.37 105.09 105.09 0 0 0-181.73 71.91 116.12 116.12 0 0 0 2.66 24c-87.28-4.3-164.73-46.3-216.56-109.82A105.48 105.48 0 0 0 68 159.6a106.27 106.27 0 0 1-47.53-13.11v1.43a105.28 105.28 0 0 0 84.21 103.06 105.67 105.67 0 0 1-47.33 1.84 105.06 105.06 0 0 0 98.14 72.94A210.72 210.72 0 0 1 25 370.84a202.17 202.17 0 0 1-25-1.43 298.85 298.85 0 0 0 160.83 46.92"/></svg></a> 180 <br/> 181 <small>© 1999-2021 ImageMagick Studio LLC</small> 182 </div> 183 </footer> 184 185 <!-- Javascript assets --> 186 <script src="../../assets/magick.js" ></script> 187 </body> 188</html> 189
