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cristy307ba182010-12-25 01:00:34 +0000[diff] [blame]178<h1>Module quantize
179 Methods</h1>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]180<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>
181
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]182<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
183_8c.html" id="QuantizeImage">QuantizeImage</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]184<div class="doc-section">
185
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]186<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]187
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]188<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]189
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]190<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]191
192<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>
193
194<pre class="text">
195 the origin.
196</pre>
197
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]198<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]199
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]200<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]201
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]202<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]203
204<p>A complete tree would require 19,173,961 nodes for k = 8, Cmax = 255.</p>
205<h5>avoid building a fully populated tree, QUANTIZE</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]206<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]207
208<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>
209
210<pre class="text">
211 n1: Number of pixels whose color is contained in the RGB cube which
212 this node represents;
213</pre>
214
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]215<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]216
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]217<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]218
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]219<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]220
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]221<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]222
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]223<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]224
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]225<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]226
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]227<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]228
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]229<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]230
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]231<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]232
233<p>Assignment generates the output image from the pruned tree. The output</p>
234<h5>parts</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]235<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]236
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]237<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]238
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]239<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]240
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]241<p>This method is based on a similar algorithm written by Paul Raveling.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]242
243 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]244<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
245_8c.html" id="AcquireQuantizeInfo">AcquireQuantizeInfo</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]246<div class="doc-section">
247
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]248<p>AcquireQuantizeInfo() allocates the QuantizeInfo structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]249
250<p>The format of the AcquireQuantizeInfo method is:</p>
251
252<pre class="code">
253 QuantizeInfo *AcquireQuantizeInfo(const ImageInfo *image_info)
254</pre>
255
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]256<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]257
258<h5>image_info</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]259<p>the image info.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]260
261 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]262<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
263_8c.html" id="CloneQuantizeInfo">CloneQuantizeInfo</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]264<div class="doc-section">
265
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]266<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]267
268<p>The format of the CloneQuantizeInfo method is:</p>
269
270<pre class="code">
271 QuantizeInfo *CloneQuantizeInfo(const QuantizeInfo *quantize_info)
272</pre>
273
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]274<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]275
276<h5>clone_info</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]277<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]278
279<h5>quantize_info</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]280<p>a structure of type info.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]281
282 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]283<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
284_8c.html" id="CompressImageColormap">CompressImageColormap</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]285<div class="doc-section">
286
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]287<p>CompressImageColormap() compresses an image colormap by removing any duplicate or unused color entries.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]288
289<p>The format of the CompressImageColormap method is:</p>
290
291<pre class="code">
292 MagickBooleanType CompressImageColormap(Image *image)
293</pre>
294
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]295<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]296
297<h5>image</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]298<p>the image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]299
300 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]301<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
302_8c.html" id="DestroyQuantizeInfo">DestroyQuantizeInfo</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]303<div class="doc-section">
304
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]305<p>DestroyQuantizeInfo() deallocates memory associated with an QuantizeInfo structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]306
307<p>The format of the DestroyQuantizeInfo method is:</p>
308
309<pre class="code">
310 QuantizeInfo *DestroyQuantizeInfo(QuantizeInfo *quantize_info)
311</pre>
312
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]313<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]314
315<h5>quantize_info</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]316<p>Specifies a pointer to an QuantizeInfo structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]317
318 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]319<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
320_8c.html" id="GetImageQuantizeError">GetImageQuantizeError</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]321<div class="doc-section">
322
323<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>
324
325<pre class="text">
326 o mean_error_per_pixel: This value is the mean error for any single
327 pixel in the image.
328</pre>
329
330<h5>normalized_mean_square_error</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]331<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]332
333<h5>normalized_maximum_square_error</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]334<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]335
336<p>The format of the GetImageQuantizeError method is:</p>
337
338<pre class="code">
339 MagickBooleanType GetImageQuantizeError(Image *image)
340</pre>
341
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]342<p>A description of each parameter follows.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]343
344<h5>image</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]345<p>the image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]346
347 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]348<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
349_8c.html" id="GetQuantizeInfo">GetQuantizeInfo</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]350<div class="doc-section">
351
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]352<p>GetQuantizeInfo() initializes the QuantizeInfo structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]353
354<p>The format of the GetQuantizeInfo method is:</p>
355
356<pre class="code">
357 GetQuantizeInfo(QuantizeInfo *quantize_info)
358</pre>
359
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]360<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]361
362<h5>quantize_info</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]363<p>Specifies a pointer to a QuantizeInfo structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]364
365 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]366<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
367_8c.html" id="PosterizeImage">PosterizeImage</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]368<div class="doc-section">
369
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]370<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]371
372<p>The format of the PosterizeImage method is:</p>
373
374<pre class="code">
cristybb503372010-05-27 20:51:26 +0000[diff] [blame]375 MagickBooleanType PosterizeImage(Image *image,const size_t levels,
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]376 const MagickBooleanType dither)
377</pre>
378
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]379<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]380
381<h5>image</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]382<p>Specifies a pointer to an Image structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]383
384<h5>levels</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]385<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]386
387<h5>dither</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]388<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]389
390 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]391<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
392_8c.html" id="QuantizeImage">QuantizeImage</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]393<div class="doc-section">
394
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]395<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]396
397<p>The format of the QuantizeImage method is:</p>
398
399<pre class="code">
400 MagickBooleanType QuantizeImage(const QuantizeInfo *quantize_info,
401 Image *image)
402</pre>
403
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]404<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]405
406<h5>quantize_info</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]407<p>Specifies a pointer to an QuantizeInfo structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]408
409<h5>image</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]410<p>the image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]411
412 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]413<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
414_8c.html" id="QuantizeImages">QuantizeImages</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]415<div class="doc-section">
416
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]417<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]418
419<p>The format of the QuantizeImages method is:</p>
420
421<pre class="code">
422 MagickBooleanType QuantizeImages(const QuantizeInfo *quantize_info,
423 Image *images)
424</pre>
425
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]426<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]427
428<h5>quantize_info</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]429<p>Specifies a pointer to an QuantizeInfo structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]430
431<h5>images</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]432<p>Specifies a pointer to a list of Image structures.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]433
434 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]435<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
436_8c.html" id="RemapImage">RemapImage</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]437<div class="doc-section">
438
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]439<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]440
441<p>The format of the RemapImage method is:</p>
442
443<pre class="code">
444 MagickBooleanType RemapImage(const QuantizeInfo *quantize_info,
445 Image *image,const Image *remap_image)
446</pre>
447
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]448<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]449
450<h5>quantize_info</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]451<p>Specifies a pointer to an QuantizeInfo structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]452
453<h5>image</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]454<p>the image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]455
456<h5>remap_image</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]457<p>the reference image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]458
459 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]460<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
461_8c.html" id="RemapImages">RemapImages</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]462<div class="doc-section">
463
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]464<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]465
466<p>The format of the RemapImage method is:</p>
467
468<pre class="code">
469 MagickBooleanType RemapImages(const QuantizeInfo *quantize_info,
470 Image *images,Image *remap_image)
471</pre>
472
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]473<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]474
475<h5>quantize_info</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]476<p>Specifies a pointer to an QuantizeInfo structure.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]477
478<h5>images</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]479<p>the image sequence.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]480
481<h5>remap_image</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]482<p>the reference image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]483
484 </div>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]485<h2><a href="http://www.wizards-toolkit.org/api/MagickCore/quantize
486_8c.html" id="SetGrayscaleImage">SetGrayscaleImage</a></h2>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]487<div class="doc-section">
488
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]489<p>SetGrayscaleImage() converts an image to a PseudoClass grayscale image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]490
491<p>The format of the SetGrayscaleImage method is:</p>
492
493<pre class="code">
494 MagickBooleanType SetGrayscaleImage(Image *image)
495</pre>
496
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]497<p>A description of each parameter follows:</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]498
499<h5>image</h5>
cristy7a40ba82011-01-08 20:31:18 +0000[diff] [blame]500<p>The image.</p>
cristy3ed852e2009-09-05 21:47:34 +0000[diff] [blame]501
502 </div>
cristy3eaa0ef2010-03-06 20:35:26 +0000[diff] [blame]503
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