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cristy307ba182010-12-25 01:00:34 +0000[diff] [blame]181<h1>Module quantize
182 Methods</h1>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]183<p class="navigation-index">[<a href="#QuantizeImage">QuantizeImage</a> &bull; <a href="#AcquireQuantizeInfo">AcquireQuantizeInfo</a> &bull; <a href="#CloneQuantizeInfo">CloneQuantizeInfo</a> &bull; <a href="#CompressImageColormap">CompressImageColormap</a> &bull; <a href="#DestroyQuantizeInfo">DestroyQuantizeInfo</a> &bull; <a href="#GetImageQuantizeError">GetImageQuantizeError</a> &bull; <a href="#GetQuantizeInfo">GetQuantizeInfo</a> &bull; <a href="#PosterizeImage">PosterizeImage</a> &bull; <a href="#QuantizeImage">QuantizeImage</a> &bull; <a href="#QuantizeImages">QuantizeImages</a> &bull; <a href="#RemapImage">RemapImage</a> &bull; <a href="#RemapImages">RemapImages</a> &bull; <a href="#SetGrayscaleImage">SetGrayscaleImage</a>]</p>
184
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]185<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
186_8c.html" id="QuantizeImage">QuantizeImage</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]187<div class="doc-section">
188
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]189<p>QuantizeImage() takes a standard RGB or monochrome images and quantizes them down to some fixed number of colors.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]190
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]191<p>For purposes of color allocation, an image is a set of n pixels, where each pixel is a point in RGB space. RGB space is a 3-dimensional vector space, and each pixel, Pi, is defined by an ordered triple of red, green, and blue coordinates, (Ri, Gi, Bi).</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]192
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]193<p>Each primary color component (red, green, or blue) represents an intensity which varies linearly from 0 to a maximum value, Cmax, which corresponds to full saturation of that color. Color allocation is defined over a domain consisting of the cube in RGB space with opposite vertices at (0,0,0) and (Cmax, Cmax, Cmax). QUANTIZE requires Cmax = 255.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]194
195<p>The algorithm maps this domain onto a tree in which each node represents a cube within that domain. In the following discussion these cubes are defined by the coordinate of two opposite vertices:</p>
196
197<pre class="text">
198 the origin.
199</pre>
200
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]201<p>The tree's root node represents the entire domain, (0,0,0) through (Cmax,Cmax,Cmax). Each lower level in the tree is generated by subdividing one node's cube into eight smaller cubes of equal size. This corresponds to bisecting the parent cube with planes passing through the midpoints of each edge.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]202
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]203<p>The basic algorithm operates in three phases: Classification, Reduction, and Assignment. Classification builds a color description tree for the image. Reduction collapses the tree until the number it represents, at most, the number of colors desired in the output image. Assignment defines the output image's color map and sets each pixel's color by restorage_class in the reduced tree. Our goal is to minimize the numerical discrepancies between the original colors and quantized colors (quantization error).</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]204
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]205<p>Classification begins by initializing a color description tree of sufficient depth to represent each possible input color in a leaf. However, it is impractical to generate a fully-formed color description tree in the storage_class phase for realistic values of Cmax. If colors components in the input image are quantized to k-bit precision, so that Cmax= 2k-1, the tree would need k levels below the root node to allow representing each possible input color in a leaf. This becomes prohibitive because the tree's total number of nodes is 1 + sum(i=1, k, 8k).</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]206
207<p>A complete tree would require 19,173,961 nodes for k = 8, Cmax = 255.</p>
208<h5>avoid building a fully populated tree, QUANTIZE</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]209<p>(1) Initializes data structures for nodes only as they are needed; (2) Chooses a maximum depth for the tree as a function of the desired number of colors in the output image (currently log2(colormap size)).</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]210
211<p>For each pixel in the input image, storage_class scans downward from the root of the color description tree. At each level of the tree it identifies the single node which represents a cube in RGB space containing the pixel's color. It updates the following data for each such node:</p>
212
213<pre class="text">
214 n1: Number of pixels whose color is contained in the RGB cube which
215 this node represents;
216</pre>
217
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]218<p>n2: Number of pixels whose color is not represented in a node at lower depth in the tree; initially, n2 = 0 for all nodes except leaves of the tree.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]219
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]220<p>Sr, Sg, Sb: Sums of the red, green, and blue component values for all pixels not classified at a lower depth. The combination of these sums and n2 will ultimately characterize the mean color of a set of pixels represented by this node.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]221
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]222<p>E: the distance squared in RGB space between each pixel contained within a node and the nodes' center. This represents the quantization error for a node.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]223
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]224<p>Reduction repeatedly prunes the tree until the number of nodes with n2 > 0 is less than or equal to the maximum number of colors allowed in the output image. On any given iteration over the tree, it selects those nodes whose E count is minimal for pruning and merges their color statistics upward. It uses a pruning threshold, Ep, to govern node selection as follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]225
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]226<p>Ep = 0 while number of nodes with (n2 > 0) > required maximum number of colors prune all nodes such that E <= Ep Set Ep to minimum E in remaining nodes</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]227
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]228<p>This has the effect of minimizing any quantization error when merging two nodes together.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]229
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]230<p>When a node to be pruned has offspring, the pruning procedure invokes itself recursively in order to prune the tree from the leaves upward. n2, Sr, Sg, and Sb in a node being pruned are always added to the corresponding data in that node's parent. This retains the pruned node's color characteristics for later averaging.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]231
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]232<p>For each node, n2 pixels exist for which that node represents the smallest volume in RGB space containing those pixel's colors. When n2 > 0 the node will uniquely define a color in the output image. At the beginning of reduction, n2 = 0 for all nodes except a the leaves of the tree which represent colors present in the input image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]233
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]234<p>The other pixel count, n1, indicates the total number of colors within the cubic volume which the node represents. This includes n1 - n2 pixels whose colors should be defined by nodes at a lower level in the tree.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]235
236<p>Assignment generates the output image from the pruned tree. The output</p>
237<h5>parts</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]238<p>(1) A color map, which is an array of color descriptions (RGB triples) for each color present in the output image; (2) A pixel array, which represents each pixel as an index into the color map array.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]239
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]240<p>First, the assignment phase makes one pass over the pruned color description tree to establish the image's color map. For each node with n2 > 0, it divides Sr, Sg, and Sb by n2 . This produces the mean color of all pixels that classify no lower than this node. Each of these colors becomes an entry in the color map.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]241
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]242<p>Finally, the assignment phase reclassifies each pixel in the pruned tree to identify the deepest node containing the pixel's color. The pixel's value in the pixel array becomes the index of this node's mean color in the color map.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]243
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]244<p>This method is based on a similar algorithm written by Paul Raveling.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]245
246 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]247<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
248_8c.html" id="AcquireQuantizeInfo">AcquireQuantizeInfo</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]249<div class="doc-section">
250
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]251<p>AcquireQuantizeInfo() allocates the QuantizeInfo structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]252
253<p>The format of the AcquireQuantizeInfo method is:</p>
254
255<pre class="code">
256 QuantizeInfo *AcquireQuantizeInfo(const ImageInfo *image_info)
257</pre>
258
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]259<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]260
261<h5>image_info</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]262<p>the image info.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]263
264 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]265<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
266_8c.html" id="CloneQuantizeInfo">CloneQuantizeInfo</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]267<div class="doc-section">
268
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]269<p>CloneQuantizeInfo() makes a duplicate of the given quantize info structure, or if quantize info is NULL, a new one.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]270
271<p>The format of the CloneQuantizeInfo method is:</p>
272
273<pre class="code">
274 QuantizeInfo *CloneQuantizeInfo(const QuantizeInfo *quantize_info)
275</pre>
276
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]277<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]278
279<h5>clone_info</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]280<p>Method CloneQuantizeInfo returns a duplicate of the given quantize info, or if image info is NULL a new one.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]281
282<h5>quantize_info</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]283<p>a structure of type info.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]284
285 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]286<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
287_8c.html" id="CompressImageColormap">CompressImageColormap</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]288<div class="doc-section">
289
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]290<p>CompressImageColormap() compresses an image colormap by removing any duplicate or unused color entries.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]291
292<p>The format of the CompressImageColormap method is:</p>
293
294<pre class="code">
295 MagickBooleanType CompressImageColormap(Image *image)
296</pre>
297
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]298<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]299
300<h5>image</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]301<p>the image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]302
303 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]304<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
305_8c.html" id="DestroyQuantizeInfo">DestroyQuantizeInfo</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]306<div class="doc-section">
307
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]308<p>DestroyQuantizeInfo() deallocates memory associated with an QuantizeInfo structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]309
310<p>The format of the DestroyQuantizeInfo method is:</p>
311
312<pre class="code">
313 QuantizeInfo *DestroyQuantizeInfo(QuantizeInfo *quantize_info)
314</pre>
315
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]316<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]317
318<h5>quantize_info</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]319<p>Specifies a pointer to an QuantizeInfo structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]320
321 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]322<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
323_8c.html" id="GetImageQuantizeError">GetImageQuantizeError</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]324<div class="doc-section">
325
326<p>GetImageQuantizeError() measures the difference between the original and quantized images. This difference is the total quantization error. The error is computed by summing over all pixels in an image the distance squared in RGB space between each reference pixel value and its quantized value. These values are computed:</p>
327
328<pre class="text">
329 o mean_error_per_pixel: This value is the mean error for any single
330 pixel in the image.
331</pre>
332
333<h5>normalized_mean_square_error</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]334<p>This value is the normalized mean quantization error for any single pixel in the image. This distance measure is normalized to a range between 0 and 1. It is independent of the range of red, green, and blue values in the image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]335
336<h5>normalized_maximum_square_error</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]337<p>Thsi value is the normalized maximum quantization error for any single pixel in the image. This distance measure is normalized to a range between 0 and 1. It is independent of the range of red, green, and blue values in your image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]338
339<p>The format of the GetImageQuantizeError method is:</p>
340
341<pre class="code">
342 MagickBooleanType GetImageQuantizeError(Image *image)
343</pre>
344
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]345<p>A description of each parameter follows.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]346
347<h5>image</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]348<p>the image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]349
350 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]351<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
352_8c.html" id="GetQuantizeInfo">GetQuantizeInfo</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]353<div class="doc-section">
354
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]355<p>GetQuantizeInfo() initializes the QuantizeInfo structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]356
357<p>The format of the GetQuantizeInfo method is:</p>
358
359<pre class="code">
360 GetQuantizeInfo(QuantizeInfo *quantize_info)
361</pre>
362
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]363<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]364
365<h5>quantize_info</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]366<p>Specifies a pointer to a QuantizeInfo structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]367
368 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]369<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
370_8c.html" id="PosterizeImage">PosterizeImage</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]371<div class="doc-section">
372
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]373<p>PosterizeImage() reduces the image to a limited number of colors for a "poster" effect.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]374
375<p>The format of the PosterizeImage method is:</p>
376
377<pre class="code">
cristybb503372010-05-27 20:51:26 +0000[diff] [blame]378 MagickBooleanType PosterizeImage(Image *image,const size_t levels,
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]379 const MagickBooleanType dither)
380</pre>
381
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]382<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]383
384<h5>image</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]385<p>Specifies a pointer to an Image structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]386
387<h5>levels</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]388<p>Number of color levels allowed in each channel. Very low values (2, 3, or 4) have the most visible effect.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]389
390<h5>dither</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]391<p>Set this integer value to something other than zero to dither the mapped image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]392
393 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]394<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
395_8c.html" id="QuantizeImage">QuantizeImage</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]396<div class="doc-section">
397
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]398<p>QuantizeImage() analyzes the colors within a reference image and chooses a fixed number of colors to represent the image. The goal of the algorithm is to minimize the color difference between the input and output image while minimizing the processing time.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]399
400<p>The format of the QuantizeImage method is:</p>
401
402<pre class="code">
403 MagickBooleanType QuantizeImage(const QuantizeInfo *quantize_info,
404 Image *image)
405</pre>
406
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]407<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]408
409<h5>quantize_info</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]410<p>Specifies a pointer to an QuantizeInfo structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]411
412<h5>image</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]413<p>the image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]414
415 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]416<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
417_8c.html" id="QuantizeImages">QuantizeImages</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]418<div class="doc-section">
419
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]420<p>QuantizeImages() analyzes the colors within a set of reference images and chooses a fixed number of colors to represent the set. The goal of the algorithm is to minimize the color difference between the input and output images while minimizing the processing time.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]421
422<p>The format of the QuantizeImages method is:</p>
423
424<pre class="code">
425 MagickBooleanType QuantizeImages(const QuantizeInfo *quantize_info,
426 Image *images)
427</pre>
428
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]429<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]430
431<h5>quantize_info</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]432<p>Specifies a pointer to an QuantizeInfo structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]433
434<h5>images</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]435<p>Specifies a pointer to a list of Image structures.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]436
437 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]438<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
439_8c.html" id="RemapImage">RemapImage</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]440<div class="doc-section">
441
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]442<p>RemapImage() replaces the colors of an image with the closest color from a reference image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]443
444<p>The format of the RemapImage method is:</p>
445
446<pre class="code">
447 MagickBooleanType RemapImage(const QuantizeInfo *quantize_info,
448 Image *image,const Image *remap_image)
449</pre>
450
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]451<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]452
453<h5>quantize_info</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]454<p>Specifies a pointer to an QuantizeInfo structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]455
456<h5>image</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]457<p>the image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]458
459<h5>remap_image</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]460<p>the reference image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]461
462 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]463<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
464_8c.html" id="RemapImages">RemapImages</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]465<div class="doc-section">
466
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]467<p>RemapImages() replaces the colors of a sequence of images with the closest color from a reference image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]468
469<p>The format of the RemapImage method is:</p>
470
471<pre class="code">
472 MagickBooleanType RemapImages(const QuantizeInfo *quantize_info,
473 Image *images,Image *remap_image)
474</pre>
475
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]476<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]477
478<h5>quantize_info</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]479<p>Specifies a pointer to an QuantizeInfo structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]480
481<h5>images</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]482<p>the image sequence.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]483
484<h5>remap_image</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]485<p>the reference image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]486
487 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]488<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
489_8c.html" id="SetGrayscaleImage">SetGrayscaleImage</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]490<div class="doc-section">
491
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]492<p>SetGrayscaleImage() converts an image to a PseudoClass grayscale image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]493
494<p>The format of the SetGrayscaleImage method is:</p>
495
496<pre class="code">
497 MagickBooleanType SetGrayscaleImage(Image *image)
498</pre>
499
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]500<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]501
502<h5>image</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]503<p>The image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]504
505 </div>
cristy3eaa0ef2010-03-06 20:35:26 +0000[diff] [blame]506
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