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164
165<div class="main">
166
cristy83543962009-10-16 19:04:28 +0000[diff] [blame]167<p class="navigation-index">[<a href="#GetImageHistogram">GetImageHistogram</a> &bull; <a href="#IsHistogramImage">IsHistogramImage</a> &bull; <a href="#IsPaletteImage">IsPaletteImage</a> &bull; <a href="#MinMaxStretchImage">MinMaxStretchImage</a> &bull; <a href="#GetNumberColors">GetNumberColors</a> &bull; <a href="#UniqueImageColors">UniqueImageColors</a>]</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]168
169<h2><a href="http://www.imagemagick.org/api/MagickCore/histogram
cristy83543962009-10-16 19:04:28 +0000[diff] [blame]170_8c.html" target="source" name="GetImageHistogram">GetImageHistogram</a></h2>
171<div class="doc-section">
172
173<p>GetImageHistogram() returns the unique colors in an image.</p></ol>
174
175<p>The format of the GetImageHistogram method is:</p>
176
177<pre class="code">
cristybb503372010-05-27 20:51:26 +0000[diff] [blame]178 size_t GetImageHistogram(const Image *image,
179 size_t *number_colors,ExceptionInfo *exception)
cristy83543962009-10-16 19:04:28 +0000[diff] [blame]180</pre>
181
182<p>A description of each parameter follows.</p></ol>
183
184<h5>image</h5>
185<ol><p>the image.</p></ol>
186
187<h5>file</h5>
188<ol><p>Write a histogram of the color distribution to this file handle.</p></ol>
189
190<h5>exception</h5>
191<ol><p>return any errors or warnings in this structure.</p></ol>
192
193 </div>
194<h2><a href="http://www.imagemagick.org/api/MagickCore/histogram
195_8c.html" target="source" name="IsHistogramImage">IsHistogramImage</a></h2>
196<div class="doc-section">
197
198<p>IsHistogramImage() returns MagickTrue if the image has 1024 unique colors or less.</p></ol>
199
200<p>The format of the IsHistogramImage method is:</p>
201
202<pre class="code">
203 MagickBooleanType IsHistogramImage(const Image *image,
204 ExceptionInfo *exception)
205</pre>
206
207<p>A description of each parameter follows.</p></ol>
208
209<h5>image</h5>
210<ol><p>the image.</p></ol>
211
212<h5>exception</h5>
213<ol><p>return any errors or warnings in this structure.</p></ol>
214
215 </div>
216<h2><a href="http://www.imagemagick.org/api/MagickCore/histogram
217_8c.html" target="source" name="IsPaletteImage">IsPaletteImage</a></h2>
218<div class="doc-section">
219
220<p>IsPaletteImage() returns MagickTrue if the image is PseudoClass and has 256 unique colors or less.</p></ol>
221
222<p>The format of the IsPaletteImage method is:</p>
223
224<pre class="code">
225 MagickBooleanType IsPaletteImage(const Image *image,
226 ExceptionInfo *exception)
227</pre>
228
229<p>A description of each parameter follows.</p></ol>
230
231<h5>image</h5>
232<ol><p>the image.</p></ol>
233
234<h5>exception</h5>
235<ol><p>return any errors or warnings in this structure.</p></ol>
236
237 </div>
238<h2><a href="http://www.imagemagick.org/api/MagickCore/histogram
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]239_8c.html" target="source" name="MinMaxStretchImage">MinMaxStretchImage</a></h2>
240<div class="doc-section">
241
242<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></ol>
243
244<p>If the adjustment values are both zero this function is equivelent to a perfect normalization (or autolevel) of the image.</p></ol>
245
246<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></ol>
247
cristy031b7a82010-04-08 00:33:24 +0000[diff] [blame]248<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></ol>
249
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]250<p>The 'SyncChannels' is turned on in the 'DefaultChannels' setting by default.</p></ol>
251
252<p>The format of the MinMaxStretchImage method is:</p>
253
254<pre class="code">
255 MagickBooleanType MinMaxStretchImage(Image *image,
256 const ChannelType channel, const double black_adjust,
257 const double white_adjust)
258</pre>
259
260<p>A description of each parameter follows:</p></ol>
261
262<h5>image</h5>
263<ol><p>The image to auto-level</p></ol>
264
265<h5>channel</h5>
266<ol><p>The channels to auto-level. If the special 'SyncChannels' flag is set, all the given channels are stretched by the same amount.</p></ol>
267
268<h5>black_adjust, white_adjust</h5>
269<ol><p>Move the Black/White Point inward from the minimum and maximum points by this color value.</p></ol>
270
271 </div>
cristy83543962009-10-16 19:04:28 +0000[diff] [blame]272<h2><a href="http://www.imagemagick.org/api/MagickCore/histogram
273_8c.html" target="source" name="GetNumberColors">GetNumberColors</a></h2>
274<div class="doc-section">
275
276<p>GetNumberColors() returns the number of unique colors in an image.</p></ol>
277
278<p>The format of the GetNumberColors method is:</p>
279
280<pre class="code">
cristybb503372010-05-27 20:51:26 +0000[diff] [blame]281 size_t GetNumberColors(const Image *image,FILE *file,
cristy83543962009-10-16 19:04:28 +0000[diff] [blame]282 ExceptionInfo *exception)
283</pre>
284
285<p>A description of each parameter follows.</p></ol>
286
287<h5>image</h5>
288<ol><p>the image.</p></ol>
289
290<h5>file</h5>
291<ol><p>Write a histogram of the color distribution to this file handle.</p></ol>
292
293<h5>exception</h5>
294<ol><p>return any errors or warnings in this structure.</p></ol>
295
296 </div>
297<h2><a href="http://www.imagemagick.org/api/MagickCore/histogram
298_8c.html" target="source" name="UniqueImageColors">UniqueImageColors</a></h2>
299<div class="doc-section">
300
301<p>UniqueImageColors() returns the unique colors of an image.</p></ol>
302
303<p>The format of the UniqueImageColors method is:</p>
304
305<pre class="code">
306 Image *UniqueImageColors(const Image *image,ExceptionInfo *exception)
307</pre>
308
309<p>A description of each parameter follows.</p></ol>
310
311<h5>image</h5>
312<ol><p>the image.</p></ol>
313
314<h5>exception</h5>
315<ol><p>return any errors or warnings in this structure.</p></ol>
316
317 </div>
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341 ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js';
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344 </script>
cristy3eaa0ef2010-03-06 20:35:26 +0000[diff] [blame]345</body>
346</html>