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84<p class="text-center"><a href="effect.html#AdaptiveBlurImage">AdaptiveBlurImage</a> &#8226; <a href="effect.html#AdaptiveSharpenImage">AdaptiveSharpenImage</a> &#8226; <a href="effect.html#BlurImage">BlurImage</a> &#8226; <a href="effect.html#ConvolveImage">ConvolveImage</a> &#8226; <a href="effect.html#DespeckleImage">DespeckleImage</a> &#8226; <a href="effect.html#EdgeImage">EdgeImage</a> &#8226; <a href="effect.html#EmbossImage">EmbossImage</a> &#8226; <a href="effect.html#GaussianBlurImage">GaussianBlurImage</a> &#8226; <a href="effect.html#KuwaharaImage">KuwaharaImage</a> &#8226; <a href="effect.html#LocalContrastImage">LocalContrastImage</a> &#8226; <a href="effect.html#MotionBlurImage">MotionBlurImage</a> &#8226; <a href="effect.html#PreviewImage">PreviewImage</a> &#8226; <a href="effect.html#RotationalBlurImage">RotationalBlurImage</a> &#8226; <a href="effect.html#SelectiveBlurImage">SelectiveBlurImage</a> &#8226; <a href="effect.html#ShadeImage">ShadeImage</a> &#8226; <a href="effect.html#SharpenImage">SharpenImage</a> &#8226; <a href="effect.html#SpreadImage">SpreadImage</a> &#8226; <a href="effect.html#UnsharpMaskImage">UnsharpMaskImage</a></p>
85
86<h2><a href="../../api/MagickCore/effect_8c.html" id="AdaptiveBlurImage">AdaptiveBlurImage</a></h2>
87
88<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>
89
90<p>The format of the AdaptiveBlurImage method is:</p>
91
92<pre class="text">
93Image *AdaptiveBlurImage(const Image *image,const double radius,
94  const double sigma,ExceptionInfo *exception)
95</pre>
96
97<p>A description of each parameter follows:</p>
98
99<dd>
100</dd>
101
102<dd> </dd>
103<dl class="dl-horizontal">
104<dt>image</dt>
105<dd>the image. </dd>
106
107<dd> </dd>
108<dt>radius</dt>
109<dd>the radius of the Gaussian, in pixels, not counting the center pixel. </dd>
110
111<dd> </dd>
112<dt>sigma</dt>
113<dd>the standard deviation of the Laplacian, in pixels. </dd>
114
115<dd> </dd>
116<dt>exception</dt>
117<dd>return any errors or warnings in this structure. </dd>
118
119<dd>  </dd>
120</dl>
121<h2><a href="../../api/MagickCore/effect_8c.html" id="AdaptiveSharpenImage">AdaptiveSharpenImage</a></h2>
122
123<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>
124
125<p>The format of the AdaptiveSharpenImage method is:</p>
126
127<pre class="text">
128Image *AdaptiveSharpenImage(const Image *image,const double radius,
129  const double sigma,ExceptionInfo *exception)
130</pre>
131
132<p>A description of each parameter follows:</p>
133
134<dd>
135</dd>
136
137<dd> </dd>
138<dl class="dl-horizontal">
139<dt>image</dt>
140<dd>the image. </dd>
141
142<dd> </dd>
143<dt>radius</dt>
144<dd>the radius of the Gaussian, in pixels, not counting the center pixel. </dd>
145
146<dd> </dd>
147<dt>sigma</dt>
148<dd>the standard deviation of the Laplacian, in pixels. </dd>
149
150<dd> </dd>
151<dt>exception</dt>
152<dd>return any errors or warnings in this structure. </dd>
153
154<dd>  </dd>
155</dl>
156<h2><a href="../../api/MagickCore/effect_8c.html" id="BlurImage">BlurImage</a></h2>
157
158<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>
159
160<p>The format of the BlurImage method is:</p>
161
162<pre class="text">
163Image *BlurImage(const Image *image,const double radius,
164  const double sigma,ExceptionInfo *exception)
165</pre>
166
167<p>A description of each parameter follows:</p>
168
169<dd>
170</dd>
171
172<dd> </dd>
173<dl class="dl-horizontal">
174<dt>image</dt>
175<dd>the image. </dd>
176
177<dd> </dd>
178<dt>radius</dt>
179<dd>the radius of the Gaussian, in pixels, not counting the center pixel. </dd>
180
181<dd> </dd>
182<dt>sigma</dt>
183<dd>the standard deviation of the Gaussian, in pixels. </dd>
184
185<dd> </dd>
186<dt>exception</dt>
187<dd>return any errors or warnings in this structure. </dd>
188
189<dd>  </dd>
190</dl>
191<h2><a href="../../api/MagickCore/effect_8c.html" id="ConvolveImage">ConvolveImage</a></h2>
192
193<p>ConvolveImage() applies a custom convolution kernel to the image.</p>
194
195<p>The format of the ConvolveImage method is:</p>
196
197<pre class="text">
198Image *ConvolveImage(const Image *image,const KernelInfo *kernel,
199  ExceptionInfo *exception)
200</pre>
201
202<p>A description of each parameter follows:</p>
203
204<dd>
205</dd>
206
207<dd> </dd>
208<dl class="dl-horizontal">
209<dt>image</dt>
210<dd>the image. </dd>
211
212<dd> </dd>
213<dt>kernel</dt>
214<dd>the filtering kernel. </dd>
215
216<dd> </dd>
217<dt>exception</dt>
218<dd>return any errors or warnings in this structure. </dd>
219
220<dd>  </dd>
221</dl>
222<h2><a href="../../api/MagickCore/effect_8c.html" id="DespeckleImage">DespeckleImage</a></h2>
223
224<p>DespeckleImage() reduces the speckle noise in an image while perserving the edges of the original image.  A speckle removing filter uses a complementary hulling technique (raising pixels that are darker than their surrounding neighbors, then complementarily lowering pixels that are brighter than their surrounding neighbors) to reduce the speckle index of that image (reference Crimmins speckle removal).</p>
225
226<p>The format of the DespeckleImage method is:</p>
227
228<pre class="text">
229Image *DespeckleImage(const Image *image,ExceptionInfo *exception)
230</pre>
231
232<p>A description of each parameter follows:</p>
233
234<dd>
235</dd>
236
237<dd> </dd>
238<dl class="dl-horizontal">
239<dt>image</dt>
240<dd>the image. </dd>
241
242<dd> </dd>
243<dt>exception</dt>
244<dd>return any errors or warnings in this structure. </dd>
245
246<dd>  </dd>
247</dl>
248<h2><a href="../../api/MagickCore/effect_8c.html" id="EdgeImage">EdgeImage</a></h2>
249
250<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>
251
252<p>The format of the EdgeImage method is:</p>
253
254<pre class="text">
255Image *EdgeImage(const Image *image,const double radius,
256  ExceptionInfo *exception)
257</pre>
258
259<p>A description of each parameter follows:</p>
260
261<dd>
262</dd>
263
264<dd> </dd>
265<dl class="dl-horizontal">
266<dt>image</dt>
267<dd>the image. </dd>
268
269<dd> </dd>
270<dt>radius</dt>
271<dd>the radius of the pixel neighborhood. </dd>
272
273<dd> </dd>
274<dt>exception</dt>
275<dd>return any errors or warnings in this structure. </dd>
276
277<dd>  </dd>
278</dl>
279<h2><a href="../../api/MagickCore/effect_8c.html" id="EmbossImage">EmbossImage</a></h2>
280
281<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>
282
283<p>The format of the EmbossImage method is:</p>
284
285<pre class="text">
286Image *EmbossImage(const Image *image,const double radius,
287  const double sigma,ExceptionInfo *exception)
288</pre>
289
290<p>A description of each parameter follows:</p>
291
292<dd>
293</dd>
294
295<dd> </dd>
296<dl class="dl-horizontal">
297<dt>image</dt>
298<dd>the image. </dd>
299
300<dd> </dd>
301<dt>radius</dt>
302<dd>the radius of the pixel neighborhood. </dd>
303
304<dd> </dd>
305<dt>sigma</dt>
306<dd>the standard deviation of the Gaussian, in pixels. </dd>
307
308<dd> </dd>
309<dt>exception</dt>
310<dd>return any errors or warnings in this structure. </dd>
311
312<dd>  </dd>
313</dl>
314<h2><a href="../../api/MagickCore/effect_8c.html" id="GaussianBlurImage">GaussianBlurImage</a></h2>
315
316<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>
317
318<p>The format of the GaussianBlurImage method is:</p>
319
320<pre class="text">
321Image *GaussianBlurImage(const Image *image,onst double radius,
322  const double sigma,ExceptionInfo *exception)
323</pre>
324
325<p>A description of each parameter follows:</p>
326
327<dd>
328</dd>
329
330<dd> </dd>
331<dl class="dl-horizontal">
332<dt>image</dt>
333<dd>the image. </dd>
334
335<dd> </dd>
336<dt>radius</dt>
337<dd>the radius of the Gaussian, in pixels, not counting the center pixel. </dd>
338
339<dd> </dd>
340<dt>sigma</dt>
341<dd>the standard deviation of the Gaussian, in pixels. </dd>
342
343<dd> </dd>
344<dt>exception</dt>
345<dd>return any errors or warnings in this structure. </dd>
346
347<dd>  </dd>
348</dl>
349<h2><a href="../../api/MagickCore/effect_8c.html" id="KuwaharaImage">KuwaharaImage</a></h2>
350
351<p>KuwaharaImage() is an edge preserving noise reduction filter.</p>
352
353<p>The format of the KuwaharaImage method is:</p>
354
355<pre class="text">
356Image *KuwaharaImage(const Image *image,const double radius,
357  const double sigma,ExceptionInfo *exception)
358</pre>
359
360<p>A description of each parameter follows:</p>
361
362<dd>
363</dd>
364
365<dd> </dd>
366<dl class="dl-horizontal">
367<dt>image</dt>
368<dd>the image. </dd>
369
370<dd> </dd>
371<dt>radius</dt>
372<dd>the square window radius. </dd>
373
374<dd> </dd>
375<dt>sigma</dt>
376<dd>the standard deviation of the Gaussian, in pixels. </dd>
377
378<dd> </dd>
379<dt>exception</dt>
380<dd>return any errors or warnings in this structure. </dd>
381
382<dd>  </dd>
383</dl>
384<h2><a href="../../api/MagickCore/effect_8c.html" id="LocalContrastImage">LocalContrastImage</a></h2>
385
386<p>LocalContrastImage() attempts to increase the appearance of large-scale light-dark transitions. Local contrast enhancement works similarly to sharpening with an unsharp mask, however the mask is instead created using an image with a greater blur distance.</p>
387
388<p>The format of the LocalContrastImage method is:</p>
389
390<pre class="text">
391Image *LocalContrastImage(const Image *image, const double radius,
392  const double strength,ExceptionInfo *exception)
393</pre>
394
395<p>A description of each parameter follows:</p>
396
397<dd>
398</dd>
399
400<dd> </dd>
401<dl class="dl-horizontal">
402<dt>image</dt>
403<dd>the image. </dd>
404
405<dd> </dd>
406<dt>radius</dt>
407<dd>the radius of the Gaussian blur, in percentage with 100 resulting in a blur radius of 20 of largest dimension. </dd>
408
409<dd> </dd>
410<dt>strength</dt>
411<dd>the strength of the blur mask in percentage. </dd>
412
413<dd> </dd>
414<dt>exception</dt>
415<dd>return any errors or warnings in this structure. </dd>
416
417<dd>  </dd>
418</dl>
419<h2><a href="../../api/MagickCore/effect_8c.html" id="MotionBlurImage">MotionBlurImage</a></h2>
420
421<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>
422
423<p>Andrew Protano contributed this effect.</p>
424
425<p>The format of the MotionBlurImage method is:</p>
426
427<pre class="text">
428    Image *MotionBlurImage(const Image *image,const double radius,
429const double sigma,const double angle,ExceptionInfo *exception)
430</pre>
431
432<p>A description of each parameter follows:</p>
433
434<dd>
435</dd>
436
437<dd> </dd>
438<dl class="dl-horizontal">
439<dt>image</dt>
440<dd>the image. </dd>
441
442<dd> </dd>
443<dt>radius</dt>
444<dd>the radius of the Gaussian, in pixels, not counting the center pixel. </dd>
445
446<dd> </dd>
447<dt>sigma</dt>
448<dd>the standard deviation of the Gaussian, in pixels. </dd>
449
450<dd> </dd>
451<dt>angle</dt>
452<dd>Apply the effect along this angle. </dd>
453
454<dd> </dd>
455<dt>exception</dt>
456<dd>return any errors or warnings in this structure. </dd>
457
458<dd>  </dd>
459</dl>
460<h2><a href="../../api/MagickCore/effect_8c.html" id="PreviewImage">PreviewImage</a></h2>
461
462<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>
463
464<p>The format of the PreviewImages method is:</p>
465
466<pre class="text">
467Image *PreviewImages(const Image *image,const PreviewType preview,
468  ExceptionInfo *exception)
469</pre>
470
471<p>A description of each parameter follows:</p>
472
473<dd>
474</dd>
475
476<dd> </dd>
477<dl class="dl-horizontal">
478<dt>image</dt>
479<dd>the image. </dd>
480
481<dd> </dd>
482<dt>preview</dt>
483<dd>the image processing operation. </dd>
484
485<dd> </dd>
486<dt>exception</dt>
487<dd>return any errors or warnings in this structure. </dd>
488
489<dd>  </dd>
490</dl>
491<h2><a href="../../api/MagickCore/effect_8c.html" id="RotationalBlurImage">RotationalBlurImage</a></h2>
492
493<p>RotationalBlurImage() applies a radial blur to the image.</p>
494
495<p>Andrew Protano contributed this effect.</p>
496
497<p>The format of the RotationalBlurImage method is:</p>
498
499<pre class="text">
500    Image *RotationalBlurImage(const Image *image,const double angle,
501ExceptionInfo *exception)
502</pre>
503
504<p>A description of each parameter follows:</p>
505
506<dd>
507</dd>
508
509<dd> </dd>
510<dl class="dl-horizontal">
511<dt>image</dt>
512<dd>the image. </dd>
513
514<dd> </dd>
515<dt>angle</dt>
516<dd>the angle of the radial blur. </dd>
517
518<dd> </dd>
519<dt>blur</dt>
520<dd>the blur. </dd>
521
522<dd> </dd>
523<dt>exception</dt>
524<dd>return any errors or warnings in this structure. </dd>
525
526<dd>  </dd>
527</dl>
528<h2><a href="../../api/MagickCore/effect_8c.html" id="SelectiveBlurImage">SelectiveBlurImage</a></h2>
529
530<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>
531
532<p>The format of the SelectiveBlurImage method is:</p>
533
534<pre class="text">
535Image *SelectiveBlurImage(const Image *image,const double radius,
536  const double sigma,const double threshold,ExceptionInfo *exception)
537</pre>
538
539<p>A description of each parameter follows:</p>
540
541<dd>
542</dd>
543
544<dd> </dd>
545<dl class="dl-horizontal">
546<dt>image</dt>
547<dd>the image. </dd>
548
549<dd> </dd>
550<dt>radius</dt>
551<dd>the radius of the Gaussian, in pixels, not counting the center pixel. </dd>
552
553<dd> </dd>
554<dt>sigma</dt>
555<dd>the standard deviation of the Gaussian, in pixels. </dd>
556
557<dd> </dd>
558<dt>threshold</dt>
559<dd>only pixels within this contrast threshold are included in the blur operation. </dd>
560
561<dd> </dd>
562<dt>exception</dt>
563<dd>return any errors or warnings in this structure. </dd>
564
565<dd>  </dd>
566</dl>
567<h2><a href="../../api/MagickCore/effect_8c.html" id="ShadeImage">ShadeImage</a></h2>
568
569<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>
570
571<p>The format of the ShadeImage method is:</p>
572
573<pre class="text">
574Image *ShadeImage(const Image *image,const MagickBooleanType gray,
575  const double azimuth,const double elevation,ExceptionInfo *exception)
576</pre>
577
578<p>A description of each parameter follows:</p>
579
580<dd>
581</dd>
582
583<dd> </dd>
584<dl class="dl-horizontal">
585<dt>image</dt>
586<dd>the image. </dd>
587
588<dd> </dd>
589<dt>gray</dt>
590<dd>A value other than zero shades the intensity of each pixel. </dd>
591
592<dd> </dd>
593<dt>azimuth, elevation</dt>
594<dd> Define the light source direction. </dd>
595
596<dd> </dd>
597<dt>exception</dt>
598<dd>return any errors or warnings in this structure. </dd>
599
600<dd>  </dd>
601</dl>
602<h2><a href="../../api/MagickCore/effect_8c.html" id="SharpenImage">SharpenImage</a></h2>
603
604<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>
605
606<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>
607
608<p>The format of the SharpenImage method is:</p>
609
610<pre class="text">
611    Image *SharpenImage(const Image *image,const double radius,
612const double sigma,ExceptionInfo *exception)
613</pre>
614
615<p>A description of each parameter follows:</p>
616
617<dd>
618</dd>
619
620<dd> </dd>
621<dl class="dl-horizontal">
622<dt>image</dt>
623<dd>the image. </dd>
624
625<dd> </dd>
626<dt>radius</dt>
627<dd>the radius of the Gaussian, in pixels, not counting the center pixel. </dd>
628
629<dd> </dd>
630<dt>sigma</dt>
631<dd>the standard deviation of the Laplacian, in pixels. </dd>
632
633<dd> </dd>
634<dt>exception</dt>
635<dd>return any errors or warnings in this structure. </dd>
636
637<dd>  </dd>
638</dl>
639<h2><a href="../../api/MagickCore/effect_8c.html" id="SpreadImage">SpreadImage</a></h2>
640
641<p>SpreadImage() is a special effects method that randomly displaces each pixel in a square area defined by the radius parameter.</p>
642
643<p>The format of the SpreadImage method is:</p>
644
645<pre class="text">
646Image *SpreadImage(const Image *image,
647  const PixelInterpolateMethod method,const double radius,
648  ExceptionInfo *exception)
649</pre>
650
651<p>A description of each parameter follows:</p>
652
653<dd>
654</dd>
655
656<dd> </dd>
657<dl class="dl-horizontal">
658<dt>image</dt>
659<dd>the image. </dd>
660
661<dd> </dd>
662<dt>method</dt>
663<dd> intepolation method. </dd>
664
665<dd> </dd>
666<dt>radius</dt>
667<dd> choose a random pixel in a neighborhood of this extent. </dd>
668
669<dd> </dd>
670<dt>exception</dt>
671<dd>return any errors or warnings in this structure. </dd>
672
673<dd>  </dd>
674</dl>
675<h2><a href="../../api/MagickCore/effect_8c.html" id="UnsharpMaskImage">UnsharpMaskImage</a></h2>
676
677<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>
678
679<p>The format of the UnsharpMaskImage method is:</p>
680
681<pre class="text">
682    Image *UnsharpMaskImage(const Image *image,const double radius,
683const double sigma,const double amount,const double threshold,
684ExceptionInfo *exception)
685</pre>
686
687<p>A description of each parameter follows:</p>
688
689<dd>
690</dd>
691
692<dd> </dd>
693<dl class="dl-horizontal">
694<dt>image</dt>
695<dd>the image. </dd>
696
697<dd> </dd>
698<dt>radius</dt>
699<dd>the radius of the Gaussian, in pixels, not counting the center pixel. </dd>
700
701<dd> </dd>
702<dt>sigma</dt>
703<dd>the standard deviation of the Gaussian, in pixels. </dd>
704
705<dd> </dd>
706<dt>gain</dt>
707<dd>the percentage of the difference between the original and the blur image that is added back into the original. </dd>
708
709<dd> </dd>
710<dt>threshold</dt>
711<dd>the threshold in pixels needed to apply the diffence gain. </dd>
712
713<dd> </dd>
714<dt>exception</dt>
715<dd>return any errors or warnings in this structure. </dd>
716
717<dd>  </dd>
718</dl>
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