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40 </script> 41 <nav class="magick-nav"> 42 <a class="magick-nav-item " href="../index.php">Home</a> 43 <a class="magick-nav-item " href="../script/binary-releases.php">Download</a> 44 <a class="magick-nav-item " href="../script/command-line-tools.php">Tools</a> 45 <a class="magick-nav-item " href="../script/command-line-options.php">Options</a> 46 <a class="magick-nav-item " href="../script/resources.php">Resources</a> 47 <a class="magick-nav-item " href="../script/api.php">Develop</a> 48 <a class="magick-nav-item " href="../script/search.php">Search</a> 49 <a class="magick-nav-item pull-right" href="http://www.imagemagick.org/discourse-server/">Community</a> 50 </nav> 51 </div> 52 </div> 53 <div class="container"> 54 <div class="magick-header"> 55 <p class="text-center"><a href="histogram.php#GetImageHistogram">GetImageHistogram</a> • <a href="histogram.php#IdentifyPaletteImage">IdentifyPaletteImage</a> • <a href="histogram.php#IsHistogramImage">IsHistogramImage</a> • <a href="histogram.php#IsPaletteImage">IsPaletteImage</a> • <a href="histogram.php#MinMaxStretchImage">MinMaxStretchImage</a> • <a href="histogram.php#GetNumberColors">GetNumberColors</a> • <a href="histogram.php#UniqueImageColors">UniqueImageColors</a></p> 56 57 <h2><a href="http://nextgen.imagemagick.org/api/MagickCore/histogram_8c.html" id="GetImageHistogram">GetImageHistogram</a></h2> 58 59 <p>GetImageHistogram() returns the unique colors in an image.</p> 60 61 <p>The format of the GetImageHistogram method is:</p> 62 63 <pre class="text"> 64 size_t GetImageHistogram(const Image *image, 65 size_t *number_colors,ExceptionInfo *exception) 66 </pre> 67 68 <p>A description of each parameter follows.</p> 69 70 <dt>image</dt> 71 <p>the image.</p> 72 73 <dt>file</dt> 74 <p>Write a histogram of the color distribution to this file handle.</p> 75 76 <dt>exception</dt> 77 <p>return any errors or warnings in this structure.</p> 78 79 <h2><a href="http://nextgen.imagemagick.org/api/MagickCore/histogram_8c.html" id="IdentifyPaletteImage">IdentifyPaletteImage</a></h2> 80 81 <p>IdentifyPaletteImage() returns MagickTrue if the image has 256 unique colors or less.</p> 82 83 <p>The format of the IdentifyPaletteImage method is:</p> 84 85 <pre class="text"> 86 MagickBooleanType IdentifyPaletteImage(const Image *image, 87 ExceptionInfo *exception) 88 </pre> 89 90 <p>A description of each parameter follows.</p> 91 92 <dt>image</dt> 93 <p>the image.</p> 94 95 <dt>exception</dt> 96 <p>return any errors or warnings in this structure.</p> 97 98 <h2><a href="http://nextgen.imagemagick.org/api/MagickCore/histogram_8c.html" id="IsHistogramImage">IsHistogramImage</a></h2> 99 100 <p>IsHistogramImage() returns MagickTrue if the image has 1024 unique colors or less.</p> 101 102 <p>The format of the IsHistogramImage method is:</p> 103 104 <pre class="text"> 105 MagickBooleanType IsHistogramImage(const Image *image, 106 ExceptionInfo *exception) 107 </pre> 108 109 <p>A description of each parameter follows.</p> 110 111 <dt>image</dt> 112 <p>the image.</p> 113 114 <dt>exception</dt> 115 <p>return any errors or warnings in this structure.</p> 116 117 <h2><a href="http://nextgen.imagemagick.org/api/MagickCore/histogram_8c.html" id="IsPaletteImage">IsPaletteImage</a></h2> 118 119 <p>IsPaletteImage() returns MagickTrue if the image is PseudoClass and has 256 unique colors or less.</p> 120 121 <p>The format of the IsPaletteImage method is:</p> 122 123 <pre class="text"> 124 MagickBooleanType IsPaletteImage(const Image *image) 125 </pre> 126 127 <p>A description of each parameter follows.</p> 128 129 <dt>image</dt> 130 <p>the image.</p> 131 132 <h2><a href="http://nextgen.imagemagick.org/api/MagickCore/histogram_8c.html" id="MinMaxStretchImage">MinMaxStretchImage</a></h2> 133 134 <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> 135 136 <p>If the adjustment values are both zero this function is equivalent to a perfect normalization (or autolevel) of the image.</p> 137 138 <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> 139 140 <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> 141 142 <p>The 'SyncChannels' is turned on in the 'DefaultChannels' setting by default.</p> 143 144 <p>The format of the MinMaxStretchImage method is:</p> 145 146 <pre class="text"> 147 MagickBooleanType MinMaxStretchImage(Image *image,const double black, 148 const double white,const double gamma,ExceptionInfo *exception) 149 </pre> 150 151 <p>A description of each parameter follows:</p> 152 153 <dd> 154 </dd> 155 156 <dd> </dd> 157 <dl class="dl-horizontal"> 158 <dt>image</dt> 159 <dd>The image to auto-level </dd> 160 161 <dd> </dd> 162 <dt>black, white</dt> 163 <dd> move the black / white point inward from the minimum and maximum points by this color value. </dd> 164 165 <dd> </dd> 166 <dt>gamma</dt> 167 <dd>the gamma. </dd> 168 169 <dd> </dd> 170 <dt>exception</dt> 171 <dd>return any errors or warnings in this structure. </dd> 172 173 <dd> </dd> 174 </dl> 175 <h2><a href="http://nextgen.imagemagick.org/api/MagickCore/histogram_8c.html" id="GetNumberColors">GetNumberColors</a></h2> 176 177 <p>GetNumberColors() returns the number of unique colors in an image.</p> 178 179 <p>The format of the GetNumberColors method is:</p> 180 181 <pre class="text"> 182 size_t GetNumberColors(const Image *image,FILE *file, 183 ExceptionInfo *exception) 184 </pre> 185 186 <p>A description of each parameter follows.</p> 187 188 <dt>image</dt> 189 <p>the image.</p> 190 191 <dt>file</dt> 192 <p>Write a histogram of the color distribution to this file handle.</p> 193 194 <dt>exception</dt> 195 <p>return any errors or warnings in this structure.</p> 196 197 <h2><a href="http://nextgen.imagemagick.org/api/MagickCore/histogram_8c.html" id="UniqueImageColors">UniqueImageColors</a></h2> 198 199 <p>UniqueImageColors() returns the unique colors of an image.</p> 200 201 <p>The format of the UniqueImageColors method is:</p> 202 203 <pre class="text"> 204 Image *UniqueImageColors(const Image *image,ExceptionInfo *exception) 205 </pre> 206 207 <p>A description of each parameter follows.</p> 208 209 <dt>image</dt> 210 <p>the image.</p> 211 212 <dt>exception</dt> 213 <p>return any errors or warnings in this structure.</p> 214 215 </div> 216 <footer class="magick-footer"> 217 <p><a href="../script/support.php">Donate</a> 218 <a href="../script/sitemap.php">Sitemap</a> 219 <a href="../script/links.php">Related</a> 220 <a href="../script/architecture.php">Architecture</a> 221 </p> 222 <p><a href="histogram.php#">Back to top</a> 223 <a href="http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x89AB63D48277377A">Public Key</a> 224 <a href="../script/contact.php">Contact Us</a></p> 225 <p><small> 1999-2016 ImageMagick Studio LLC</small></p> 226 </footer> 227 </div><!-- /.container --> 228 229 <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.3/jquery.min.js"></script> 230 <script src="http://nextgen.imagemagick.org/js/magick.php"></script> 231 </div> 232 </body> 233 </html> 234
