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146<div class="main">
147
148<p class="navigation-index">[<a href="#AdaptiveBlurImage">AdaptiveBlurImage</a> &bull; <a href="#AdaptiveSharpenImage">AdaptiveSharpenImage</a> &bull; <a href="#BlurImage">BlurImage</a> &bull; <a href="#DespeckleImage">DespeckleImage</a> &bull; <a href="#EdgeImage">EdgeImage</a> &bull; <a href="#EmbossImage">EmbossImage</a> &bull; <a href="#GaussianBlurImage">GaussianBlurImage</a> &bull; <a href="#MedianFilterImage">MedianFilterImage</a> &bull; <a href="#MotionBlurImage">MotionBlurImage</a> &bull; <a href="#PreviewImage">PreviewImage</a> &bull; <a href="#RadialBlurImage">RadialBlurImage</a> &bull; <a href="#ReduceNoiseImage">ReduceNoiseImage</a> &bull; <a href="#SelectiveBlurImage">SelectiveBlurImage</a> &bull; <a href="#ShadeImage">ShadeImage</a> &bull; <a href="#SharpenImage">SharpenImage</a> &bull; <a href="#SpreadImage">SpreadImage</a> &bull; <a href="#UnsharpMaskImage">UnsharpMaskImage</a>]</p>
149
150<h2><a href="http://www.imagemagick.org/api/MagickCore/effect
151_8c.html" target="source" name="AdaptiveBlurImage">AdaptiveBlurImage</a></h2>
152<div class="doc-section">
153
154<p>AdaptiveBlurImage() adaptively blurs the image by blurring less intensely near image edges and more intensely far from edges. We blur the image with a Gaussian operator of the given radius and standard deviation (sigma). For reasonable results, radius should be larger than sigma. Use a radius of 0 and AdaptiveBlurImage() selects a suitable radius for you.</p></ol>
155
156<p>The format of the AdaptiveBlurImage method is:</p>
157
158<pre class="code">
159 Image *AdaptiveBlurImage(const Image *image,const double radius,
160 const double sigma,ExceptionInfo *exception)
161 Image *AdaptiveBlurImageChannel(const Image *image,
162 const ChannelType channel,double radius,const double sigma,
163 ExceptionInfo *exception)
164</pre>
165
166<p>A description of each parameter follows:</p></ol>
167
168<h5>image</h5>
169<ol><p>the image.</p></ol>
170
171<h5>channel</h5>
172<ol><p>the channel type.</p></ol>
173
174<h5>radius</h5>
175<ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
176
177<h5>sigma</h5>
178<ol><p>the standard deviation of the Laplacian, in pixels.</p></ol>
179
180<h5>exception</h5>
181<ol><p>return any errors or warnings in this structure.</p></ol>
182
183 </div>
184<h2><a href="http://www.imagemagick.org/api/MagickCore/effect
185_8c.html" target="source" name="AdaptiveSharpenImage">AdaptiveSharpenImage</a></h2>
186<div class="doc-section">
187
188<p>AdaptiveSharpenImage() adaptively sharpens the image by sharpening more intensely near image edges and less intensely far from edges. We sharpen the image with a Gaussian operator of the given radius and standard deviation (sigma). For reasonable results, radius should be larger than sigma. Use a radius of 0 and AdaptiveSharpenImage() selects a suitable radius for you.</p></ol>
189
190<p>The format of the AdaptiveSharpenImage method is:</p>
191
192<pre class="code">
193 Image *AdaptiveSharpenImage(const Image *image,const double radius,
194 const double sigma,ExceptionInfo *exception)
195 Image *AdaptiveSharpenImageChannel(const Image *image,
196 const ChannelType channel,double radius,const double sigma,
197 ExceptionInfo *exception)
198</pre>
199
200<p>A description of each parameter follows:</p></ol>
201
202<h5>image</h5>
203<ol><p>the image.</p></ol>
204
205<h5>channel</h5>
206<ol><p>the channel type.</p></ol>
207
208<h5>radius</h5>
209<ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
210
211<h5>sigma</h5>
212<ol><p>the standard deviation of the Laplacian, in pixels.</p></ol>
213
214<h5>exception</h5>
215<ol><p>return any errors or warnings in this structure.</p></ol>
216
217 </div>
218<h2><a href="http://www.imagemagick.org/api/MagickCore/effect
219_8c.html" target="source" name="BlurImage">BlurImage</a></h2>
220<div class="doc-section">
221
222<p>BlurImage() blurs an image. We convolve the image with a Gaussian operator of the given radius and standard deviation (sigma). For reasonable results, the radius should be larger than sigma. Use a radius of 0 and BlurImage() selects a suitable radius for you.</p></ol>
223
224<p>BlurImage() differs from GaussianBlurImage() in that it uses a separable kernel which is faster but mathematically equivalent to the non-separable kernel.</p></ol>
225
226<p>The format of the BlurImage method is:</p>
227
228<pre class="code">
229 Image *BlurImage(const Image *image,const double radius,
230 const double sigma,ExceptionInfo *exception)
231 Image *BlurImageChannel(const Image *image,const ChannelType channel,
232 const double radius,const double sigma,ExceptionInfo *exception)
233</pre>
234
235<p>A description of each parameter follows:</p></ol>
236
237<h5>image</h5>
238<ol><p>the image.</p></ol>
239
240<h5>channel</h5>
241<ol><p>the channel type.</p></ol>
242
243<h5>radius</h5>
244<ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
245
246<h5>sigma</h5>
247<ol><p>the standard deviation of the Gaussian, in pixels.</p></ol>
248
249<h5>exception</h5>
250<ol><p>return any errors or warnings in this structure.</p></ol>
251
252 </div>
253<h2><a href="http://www.imagemagick.org/api/MagickCore/effect
254_8c.html" target="source" name="DespeckleImage">DespeckleImage</a></h2>
255<div class="doc-section">
256
257<p>DespeckleImage() reduces the speckle noise in an image while perserving the edges of the original image.</p></ol>
258
259<p>The format of the DespeckleImage method is:</p>
260
261<pre class="code">
262 Image *DespeckleImage(const Image *image,ExceptionInfo *exception)
263</pre>
264
265<p>A description of each parameter follows:</p></ol>
266
267<h5>image</h5>
268<ol><p>the image.</p></ol>
269
270<h5>exception</h5>
271<ol><p>return any errors or warnings in this structure.</p></ol>
272
273 </div>
274<h2><a href="http://www.imagemagick.org/api/MagickCore/effect
275_8c.html" target="source" name="EdgeImage">EdgeImage</a></h2>
276<div class="doc-section">
277
278<p>EdgeImage() finds edges in an image. Radius defines the radius of the convolution filter. Use a radius of 0 and EdgeImage() selects a suitable radius for you.</p></ol>
279
280<p>The format of the EdgeImage method is:</p>
281
282<pre class="code">
283 Image *EdgeImage(const Image *image,const double radius,
284 ExceptionInfo *exception)
285</pre>
286
287<p>A description of each parameter follows:</p></ol>
288
289<h5>image</h5>
290<ol><p>the image.</p></ol>
291
292<h5>radius</h5>
293<ol><p>the radius of the pixel neighborhood.</p></ol>
294
295<h5>exception</h5>
296<ol><p>return any errors or warnings in this structure.</p></ol>
297
298 </div>
299<h2><a href="http://www.imagemagick.org/api/MagickCore/effect
300_8c.html" target="source" name="EmbossImage">EmbossImage</a></h2>
301<div class="doc-section">
302
303<p>EmbossImage() returns a grayscale image with a three-dimensional effect. We convolve the image with a Gaussian operator of the given radius and standard deviation (sigma). For reasonable results, radius should be larger than sigma. Use a radius of 0 and Emboss() selects a suitable radius for you.</p></ol>
304
305<p>The format of the EmbossImage method is:</p>
306
307<pre class="code">
308 Image *EmbossImage(const Image *image,const double radius,
309 const double sigma,ExceptionInfo *exception)
310</pre>
311
312<p>A description of each parameter follows:</p></ol>
313
314<h5>image</h5>
315<ol><p>the image.</p></ol>
316
317<h5>radius</h5>
318<ol><p>the radius of the pixel neighborhood.</p></ol>
319
320<h5>sigma</h5>
321<ol><p>the standard deviation of the Gaussian, in pixels.</p></ol>
322
323<h5>exception</h5>
324<ol><p>return any errors or warnings in this structure.</p></ol>
325
326 </div>
327<h2><a href="http://www.imagemagick.org/api/MagickCore/effect
328_8c.html" target="source" name="GaussianBlurImage">GaussianBlurImage</a></h2>
329<div class="doc-section">
330
331<p>GaussianBlurImage() blurs an image. We convolve the image with a Gaussian operator of the given radius and standard deviation (sigma). For reasonable results, the radius should be larger than sigma. Use a radius of 0 and GaussianBlurImage() selects a suitable radius for you</p></ol>
332
333<p>The format of the GaussianBlurImage method is:</p>
334
335<pre class="code">
336 Image *GaussianBlurImage(const Image *image,onst double radius,
337 const double sigma,ExceptionInfo *exception)
338 Image *GaussianBlurImageChannel(const Image *image,
339 const ChannelType channel,const double radius,const double sigma,
340 ExceptionInfo *exception)
341</pre>
342
343<p>A description of each parameter follows:</p></ol>
344
345<h5>image</h5>
346<ol><p>the image.</p></ol>
347
348<h5>channel</h5>
349<ol><p>the channel type.</p></ol>
350
351<h5>radius</h5>
352<ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
353
354<h5>sigma</h5>
355<ol><p>the standard deviation of the Gaussian, in pixels.</p></ol>
356
357<h5>exception</h5>
358<ol><p>return any errors or warnings in this structure.</p></ol>
359
360 </div>
361<h2><a href="http://www.imagemagick.org/api/MagickCore/effect
362_8c.html" target="source" name="MedianFilterImage">MedianFilterImage</a></h2>
363<div class="doc-section">
364
365<p>MedianFilterImage() applies a digital filter that improves the quality of a noisy image. Each pixel is replaced by the median in a set of neighboring pixels as defined by radius.</p></ol>
366
367<p>The algorithm was contributed by Mike Edmonds and implements an insertion sort for selecting median color-channel values. For more on this algorithm see "Skip Lists: A probabilistic Alternative to Balanced Trees" by William Pugh in the June 1990 of Communications of the ACM.</p></ol>
368
369<p>The format of the MedianFilterImage method is:</p>
370
371<pre class="code">
372 Image *MedianFilterImage(const Image *image,const double radius,
373 ExceptionInfo *exception)
374</pre>
375
376<p>A description of each parameter follows:</p></ol>
377
378<h5>image</h5>
379<ol><p>the image.</p></ol>
380
381<h5>radius</h5>
382<ol><p>the radius of the pixel neighborhood.</p></ol>
383
384<h5>exception</h5>
385<ol><p>return any errors or warnings in this structure.</p></ol>
386
387 </div>
388<h2><a href="http://www.imagemagick.org/api/MagickCore/effect
389_8c.html" target="source" name="MotionBlurImage">MotionBlurImage</a></h2>
390<div class="doc-section">
391
392<p>MotionBlurImage() simulates motion blur. We convolve the image with a Gaussian operator of the given radius and standard deviation (sigma). For reasonable results, radius should be larger than sigma. Use a radius of 0 and MotionBlurImage() selects a suitable radius for you. Angle gives the angle of the blurring motion.</p></ol>
393
394<p>Andrew Protano contributed this effect.</p></ol>
395
396<p>The format of the MotionBlurImage method is:</p>
397
398<pre class="code">
399 Image *MotionBlurImage(const Image *image,const double radius,
400 const double sigma,const double angle,ExceptionInfo *exception)
401 Image *MotionBlurImageChannel(const Image *image,const ChannelType channel,
402 const double radius,const double sigma,const double angle,
403 ExceptionInfo *exception)
404</pre>
405
406<p>A description of each parameter follows:</p></ol>
407
408<h5>image</h5>
409<ol><p>the image.</p></ol>
410
411<h5>channel</h5>
412<ol><p>the channel type.</p></ol>
413
414<h5>radius</h5>
415<ol><p>the radius of the Gaussian, in pixels, not counting the center</p>
416<h5>radius</h5>
417<ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
418
419<h5>sigma</h5>
420<ol><p>the standard deviation of the Gaussian, in pixels.</p></ol>
421
422<h5>angle</h5>
423<ol><p>Apply the effect along this angle.</p></ol>
424
425<h5>exception</h5>
426<ol><p>return any errors or warnings in this structure.</p></ol>
427
428 </div>
429<h2><a href="http://www.imagemagick.org/api/MagickCore/effect
430_8c.html" target="source" name="PreviewImage">PreviewImage</a></h2>
431<div class="doc-section">
432
433<p>PreviewImage() tiles 9 thumbnails of the specified image with an image processing operation applied with varying parameters. This may be helpful pin-pointing an appropriate parameter for a particular image processing operation.</p></ol>
434
435<p>The format of the PreviewImages method is:</p>
436
437<pre class="code">
438 Image *PreviewImages(const Image *image,const PreviewType preview,
439 ExceptionInfo *exception)
440</pre>
441
442<p>A description of each parameter follows:</p></ol>
443
444<h5>image</h5>
445<ol><p>the image.</p></ol>
446
447<h5>preview</h5>
448<ol><p>the image processing operation.</p></ol>
449
450<h5>exception</h5>
451<ol><p>return any errors or warnings in this structure.</p></ol>
452
453 </div>
454<h2><a href="http://www.imagemagick.org/api/MagickCore/effect
455_8c.html" target="source" name="RadialBlurImage">RadialBlurImage</a></h2>
456<div class="doc-section">
457
458<p>RadialBlurImage() applies a radial blur to the image.</p></ol>
459
460<p>Andrew Protano contributed this effect.</p></ol>
461
462<p>The format of the RadialBlurImage method is:</p>
463
464<pre class="code">
465 Image *RadialBlurImage(const Image *image,const double angle,
466 ExceptionInfo *exception)
467 Image *RadialBlurImageChannel(const Image *image,const ChannelType channel,
468 const double angle,ExceptionInfo *exception)
469</pre>
470
471<p>A description of each parameter follows:</p></ol>
472
473<h5>image</h5>
474<ol><p>the image.</p></ol>
475
476<h5>channel</h5>
477<ol><p>the channel type.</p></ol>
478
479<h5>angle</h5>
480<ol><p>the angle of the radial blur.</p></ol>
481
482<h5>exception</h5>
483<ol><p>return any errors or warnings in this structure.</p></ol>
484
485 </div>
486<h2><a href="http://www.imagemagick.org/api/MagickCore/effect
487_8c.html" target="source" name="ReduceNoiseImage">ReduceNoiseImage</a></h2>
488<div class="doc-section">
489
490<p>ReduceNoiseImage() smooths the contours of an image while still preserving edge information. The algorithm works by replacing each pixel with its neighbor closest in value. A neighbor is defined by radius. Use a radius of 0 and ReduceNoise() selects a suitable radius for you.</p></ol>
491
492<p>The format of the ReduceNoiseImage method is:</p>
493
494<pre class="code">
495 Image *ReduceNoiseImage(const Image *image,const double radius,
496 ExceptionInfo *exception)
497</pre>
498
499<p>A description of each parameter follows:</p></ol>
500
501<h5>image</h5>
502<ol><p>the image.</p></ol>
503
504<h5>radius</h5>
505<ol><p>the radius of the pixel neighborhood.</p></ol>
506
507<h5>exception</h5>
508<ol><p>return any errors or warnings in this structure.</p></ol>
509
510 </div>
511<h2><a href="http://www.imagemagick.org/api/MagickCore/effect
512_8c.html" target="source" name="SelectiveBlurImage">SelectiveBlurImage</a></h2>
513<div class="doc-section">
514
515<p>SelectiveBlurImage() selectively blur pixels within a contrast threshold. It is similar to the unsharpen mask that sharpens everything with contrast above a certain threshold.</p></ol>
516
517<p>The format of the SelectiveBlurImage method is:</p>
518
519<pre class="code">
520 Image *SelectiveBlurImage(const Image *image,const double radius,
521 const double sigma,const double threshold,ExceptionInfo *exception)
522 Image *SelectiveBlurImageChannel(const Image *image,
523 const ChannelType channel,const double radius,const double sigma,
524 const double threshold,ExceptionInfo *exception)
525</pre>
526
527<p>A description of each parameter follows:</p></ol>
528
529<h5>image</h5>
530<ol><p>the image.</p></ol>
531
532<h5>channel</h5>
533<ol><p>the channel type.</p></ol>
534
535<h5>radius</h5>
536<ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
537
538<h5>sigma</h5>
539<ol><p>the standard deviation of the Gaussian, in pixels.</p></ol>
540
541<h5>threshold</h5>
542<ol><p>only pixels within this contrast threshold are included in the blur operation.</p></ol>
543
544<h5>exception</h5>
545<ol><p>return any errors or warnings in this structure.</p></ol>
546
547 </div>
548<h2><a href="http://www.imagemagick.org/api/MagickCore/effect
549_8c.html" target="source" name="ShadeImage">ShadeImage</a></h2>
550<div class="doc-section">
551
552<p>ShadeImage() shines a distant light on an image to create a three-dimensional effect. You control the positioning of the light with azimuth and elevation; azimuth is measured in degrees off the x axis and elevation is measured in pixels above the Z axis.</p></ol>
553
554<p>The format of the ShadeImage method is:</p>
555
556<pre class="code">
557 Image *ShadeImage(const Image *image,const MagickBooleanType gray,
558 const double azimuth,const double elevation,ExceptionInfo *exception)
559</pre>
560
561<p>A description of each parameter follows:</p></ol>
562
563<h5>image</h5>
564<ol><p>the image.</p></ol>
565
566<h5>gray</h5>
567<ol><p>A value other than zero shades the intensity of each pixel.</p></ol>
568
569<h5>azimuth, elevation</h5>
570<ol><p>Define the light source direction.</p></ol>
571
572<h5>exception</h5>
573<ol><p>return any errors or warnings in this structure.</p></ol>
574
575 </div>
576<h2><a href="http://www.imagemagick.org/api/MagickCore/effect
577_8c.html" target="source" name="SharpenImage">SharpenImage</a></h2>
578<div class="doc-section">
579
580<p>SharpenImage() sharpens the image. We convolve the image with a Gaussian operator of the given radius and standard deviation (sigma). For reasonable results, radius should be larger than sigma. Use a radius of 0 and SharpenImage() selects a suitable radius for you.</p></ol>
581
582<p>Using a separable kernel would be faster, but the negative weights cancel out on the corners of the kernel producing often undesirable ringing in the filtered result; this can be avoided by using a 2D gaussian shaped image sharpening kernel instead.</p></ol>
583
584<p>The format of the SharpenImage method is:</p>
585
586<pre class="code">
587 Image *SharpenImage(const Image *image,const double radius,
588 const double sigma,ExceptionInfo *exception)
589 Image *SharpenImageChannel(const Image *image,const ChannelType channel,
590 const double radius,const double sigma,ExceptionInfo *exception)
591</pre>
592
593<p>A description of each parameter follows:</p></ol>
594
595<h5>image</h5>
596<ol><p>the image.</p></ol>
597
598<h5>channel</h5>
599<ol><p>the channel type.</p></ol>
600
601<h5>radius</h5>
602<ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
603
604<h5>sigma</h5>
605<ol><p>the standard deviation of the Laplacian, in pixels.</p></ol>
606
607<h5>exception</h5>
608<ol><p>return any errors or warnings in this structure.</p></ol>
609
610 </div>
611<h2><a href="http://www.imagemagick.org/api/MagickCore/effect
612_8c.html" target="source" name="SpreadImage">SpreadImage</a></h2>
613<div class="doc-section">
614
615<p>SpreadImage() is a special effects method that randomly displaces each pixel in a block defined by the radius parameter.</p></ol>
616
617<p>The format of the SpreadImage method is:</p>
618
619<pre class="code">
620 Image *SpreadImage(const Image *image,const double radius,
621 ExceptionInfo *exception)
622</pre>
623
624<p>A description of each parameter follows:</p></ol>
625
626<h5>image</h5>
627<ol><p>the image.</p></ol>
628
629<h5>radius</h5>
630<ol><p>Choose a random pixel in a neighborhood of this extent.</p></ol>
631
632<h5>exception</h5>
633<ol><p>return any errors or warnings in this structure.</p></ol>
634
635 </div>
636<h2><a href="http://www.imagemagick.org/api/MagickCore/effect
637_8c.html" target="source" name="UnsharpMaskImage">UnsharpMaskImage</a></h2>
638<div class="doc-section">
639
640<p>UnsharpMaskImage() sharpens one or more image channels. We convolve the image with a Gaussian operator of the given radius and standard deviation (sigma). For reasonable results, radius should be larger than sigma. Use a radius of 0 and UnsharpMaskImage() selects a suitable radius for you.</p></ol>
641
642<p>The format of the UnsharpMaskImage method is:</p>
643
644<pre class="code">
645 Image *UnsharpMaskImage(const Image *image,const double radius,
646 const double sigma,const double amount,const double threshold,
647 ExceptionInfo *exception)
648 Image *UnsharpMaskImageChannel(const Image *image,
649 const ChannelType channel,const double radius,const double sigma,
650 const double amount,const double threshold,ExceptionInfo *exception)
651</pre>
652
653<p>A description of each parameter follows:</p></ol>
654
655<h5>image</h5>
656<ol><p>the image.</p></ol>
657
658<h5>channel</h5>
659<ol><p>the channel type.</p></ol>
660
661<h5>radius</h5>
662<ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
663
664<h5>sigma</h5>
665<ol><p>the standard deviation of the Gaussian, in pixels.</p></ol>
666
667<h5>amount</h5>
668<ol><p>the percentage of the difference between the original and the blur image that is added back into the original.</p></ol>
669
670<h5>threshold</h5>
671<ol><p>the threshold in pixels needed to apply the diffence amount.</p></ol>
672
673<h5>exception</h5>
674<ol><p>return any errors or warnings in this structure.</p></ol>
675
676 </div>
677
678</div>
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