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77 </script> 78 79 </div> 80 </header> 81 <main class="container"> 82 <div class="magick-template"> 83<div class="magick-header"> 84<p class="text-center"><a href="histogram.html#GetImageHistogram">GetImageHistogram</a> • <a href="histogram.html#IdentifyPaletteImage">IdentifyPaletteImage</a> • <a href="histogram.html#IsHistogramImage">IsHistogramImage</a> • <a href="histogram.html#IsPaletteImage">IsPaletteImage</a> • <a href="histogram.html#MinMaxStretchImage">MinMaxStretchImage</a> • <a href="histogram.html#GetNumberColors">GetNumberColors</a> • <a href="histogram.html#UniqueImageColors">UniqueImageColors</a></p> 85 86<h2><a href="../../api/MagickCore/histogram_8c.html" id="GetImageHistogram">GetImageHistogram</a></h2> 87 88<p>GetImageHistogram() returns the unique colors in an image.</p> 89 90<p>The format of the GetImageHistogram method is:</p> 91 92<pre class="text"> 93size_t GetImageHistogram(const Image *image, 94 size_t *number_colors,ExceptionInfo *exception) 95</pre> 96 97<p>A description of each parameter follows.</p> 98 99<dt>image</dt> 100<p>the image.</p> 101 102<dt>file</dt> 103<p>Write a histogram of the color distribution to this file handle.</p> 104 105<dt>exception</dt> 106<p>return any errors or warnings in this structure.</p> 107 108<h2><a href="../../api/MagickCore/histogram_8c.html" id="IdentifyPaletteImage">IdentifyPaletteImage</a></h2> 109 110<p>IdentifyPaletteImage() returns MagickTrue if the image has 256 unique colors or less.</p> 111 112<p>The format of the IdentifyPaletteImage method is:</p> 113 114<pre class="text"> 115MagickBooleanType IdentifyPaletteImage(const Image *image, 116 ExceptionInfo *exception) 117</pre> 118 119<p>A description of each parameter follows.</p> 120 121<dt>image</dt> 122<p>the image.</p> 123 124<dt>exception</dt> 125<p>return any errors or warnings in this structure.</p> 126 127<h2><a href="../../api/MagickCore/histogram_8c.html" id="IsHistogramImage">IsHistogramImage</a></h2> 128 129<p>IsHistogramImage() returns MagickTrue if the image has 1024 unique colors or less.</p> 130 131<p>The format of the IsHistogramImage method is:</p> 132 133<pre class="text"> 134MagickBooleanType IsHistogramImage(const Image *image, 135 ExceptionInfo *exception) 136</pre> 137 138<p>A description of each parameter follows.</p> 139 140<dt>image</dt> 141<p>the image.</p> 142 143<dt>exception</dt> 144<p>return any errors or warnings in this structure.</p> 145 146<h2><a href="../../api/MagickCore/histogram_8c.html" id="IsPaletteImage">IsPaletteImage</a></h2> 147 148<p>IsPaletteImage() returns MagickTrue if the image is PseudoClass and has 256 unique colors or less.</p> 149 150<p>The format of the IsPaletteImage method is:</p> 151 152<pre class="text"> 153MagickBooleanType IsPaletteImage(const Image *image) 154</pre> 155 156<p>A description of each parameter follows.</p> 157 158<dt>image</dt> 159<p>the image.</p> 160 161<h2><a href="../../api/MagickCore/histogram_8c.html" id="MinMaxStretchImage">MinMaxStretchImage</a></h2> 162 163<p>MinMaxStretchImage() uses the exact minimum and maximum values found in each of the channels given, as the BlackPoint and WhitePoint to linearly stretch the colors (and histogram) of the image. The stretch points are also moved further inward by the adjustment values given.</p> 164 165<p>If the adjustment values are both zero this function is equivalent to a perfect normalization (or autolevel) of the image.</p> 166 167<p>Each channel is stretched independantally of each other (producing color distortion) unless the special 'SyncChannels' flag is also provided in the channels setting. If this flag is present the minimum and maximum point will be extracted from all the given channels, and those channels will be stretched by exactly the same amount (preventing color distortion).</p> 168 169<p>In the special case that only ONE value is found in a channel of the image that value is not stretched, that value is left as is.</p> 170 171<p>The 'SyncChannels' is turned on in the 'DefaultChannels' setting by default.</p> 172 173<p>The format of the MinMaxStretchImage method is:</p> 174 175<pre class="text"> 176MagickBooleanType MinMaxStretchImage(Image *image,const double black, 177 const double white,const double gamma,ExceptionInfo *exception) 178</pre> 179 180<p>A description of each parameter follows:</p> 181 182<dd> 183</dd> 184 185<dd> </dd> 186<dl class="dl-horizontal"> 187<dt>image</dt> 188<dd>The image to auto-level </dd> 189 190<dd> </dd> 191<dt>black, white</dt> 192<dd> move the black / white point inward from the minimum and maximum points by this color value. </dd> 193 194<dd> </dd> 195<dt>gamma</dt> 196<dd>the gamma. </dd> 197 198<dd> </dd> 199<dt>exception</dt> 200<dd>return any errors or warnings in this structure. </dd> 201 202<dd> </dd> 203</dl> 204<h2><a href="../../api/MagickCore/histogram_8c.html" id="GetNumberColors">GetNumberColors</a></h2> 205 206<p>GetNumberColors() returns the number of unique colors in an image.</p> 207 208<p>The format of the GetNumberColors method is:</p> 209 210<pre class="text"> 211size_t GetNumberColors(const Image *image,FILE *file, 212 ExceptionInfo *exception) 213</pre> 214 215<p>A description of each parameter follows.</p> 216 217<dt>image</dt> 218<p>the image.</p> 219 220<dt>file</dt> 221<p>Write a histogram of the color distribution to this file handle.</p> 222 223<dt>exception</dt> 224<p>return any errors or warnings in this structure.</p> 225 226<h2><a href="../../api/MagickCore/histogram_8c.html" id="UniqueImageColors">UniqueImageColors</a></h2> 227 228<p>UniqueImageColors() returns the unique colors of an image.</p> 229 230<p>The format of the UniqueImageColors method is:</p> 231 232<pre class="text"> 233Image *UniqueImageColors(const Image *image,ExceptionInfo *exception) 234</pre> 235 236<p>A description of each parameter follows.</p> 237 238<dt>image</dt> 239<p>the image.</p> 240 241<dt>exception</dt> 242<p>return any errors or warnings in this structure.</p> 243 244</div> 245 </div> 246 </main><!-- /.container --> 247 <footer class="magick-footer"> 248 <p><a href="../../www/security-policy.html">Security</a> • 249 <a href="../../www/architecture.html">Architecture</a> • 250 <a href="../../www/links.html">Related</a> • 251 <a href="../../www/sitemap.html">Sitemap</a> 252 253 <a href="histogram.html#"><img class="d-inline" id="wand" alt="And Now a Touch of Magick" width="16" height="16" src="../../images/wand.ico"/></a> 254 255 <a href="http://pgp.mit.edu/pks/lookup?op=get&search=0x89AB63D48277377A">Public Key</a> • 256 <a href="../../www/support.html">Donate</a> • 257 <a href="../../www/contact.html">Contact Us</a> 258 <br/> 259 <small>© 1999-2019 ImageMagick Studio LLC</small></p> 260 </footer> 261 262 <!-- Javascript assets --> 263 <script src="../assets/magick.js" crossorigin="anonymous"></script> 264 <script>window.jQuery || document.write('<script src="https://localhost/ajax/libs/jquery/3.3.1/jquery.min.js"><\/script>')</script> 265</body> 266</html> 267<!-- Magick Cache 2nd January 2019 17:24 -->
