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158 <p class="navigation-index">[<a href="#AdaptiveBlurImage">AdaptiveBlurImage</a> • <a href="#AdaptiveSharpenImage">AdaptiveSharpenImage</a> • <a href="#BlurImage">BlurImage</a> • <a href="#ConvolveImage">ConvolveImage</a> • <a href="#DespeckleImage">DespeckleImage</a> • <a href="#EdgeImage">EdgeImage</a> • <a href="#EmbossImage">EmbossImage</a> • <a href="#FilterImage">FilterImage</a> • <a href="#GaussianBlurImage">GaussianBlurImage</a> • <a href="#MedianFilterImage">MedianFilterImage</a> • <a href="#MotionBlurImage">MotionBlurImage</a> • <a href="#PreviewImage">PreviewImage</a> • <a href="#RadialBlurImage">RadialBlurImage</a> • <a href="#ReduceNoiseImage">ReduceNoiseImage</a> • <a href="#SelectiveBlurImage">SelectiveBlurImage</a> • <a href="#ShadeImage">ShadeImage</a> • <a href="#SharpenImage">SharpenImage</a> • <a href="#SpreadImage">SpreadImage</a> • <a href="#UnsharpMaskImage">UnsharpMaskImage</a>]</p>
160 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
161 _8c.html" target="source" name="AdaptiveBlurImage">AdaptiveBlurImage</a></h2>
162 <div class="doc-section">
164 <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>
166 <p>The format of the AdaptiveBlurImage method is:</p>
169 Image *AdaptiveBlurImage(const Image *image,const double radius,
170 const double sigma,ExceptionInfo *exception)
171 Image *AdaptiveBlurImageChannel(const Image *image,
172 const ChannelType channel,double radius,const double sigma,
173 ExceptionInfo *exception)
176 <p>A description of each parameter follows:</p></ol>
179 <ol><p>the image.</p></ol>
182 <ol><p>the channel type.</p></ol>
185 <ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
188 <ol><p>the standard deviation of the Laplacian, in pixels.</p></ol>
191 <ol><p>return any errors or warnings in this structure.</p></ol>
194 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
195 _8c.html" target="source" name="AdaptiveSharpenImage">AdaptiveSharpenImage</a></h2>
196 <div class="doc-section">
198 <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>
200 <p>The format of the AdaptiveSharpenImage method is:</p>
203 Image *AdaptiveSharpenImage(const Image *image,const double radius,
204 const double sigma,ExceptionInfo *exception)
205 Image *AdaptiveSharpenImageChannel(const Image *image,
206 const ChannelType channel,double radius,const double sigma,
207 ExceptionInfo *exception)
210 <p>A description of each parameter follows:</p></ol>
213 <ol><p>the image.</p></ol>
216 <ol><p>the channel type.</p></ol>
219 <ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
222 <ol><p>the standard deviation of the Laplacian, in pixels.</p></ol>
225 <ol><p>return any errors or warnings in this structure.</p></ol>
228 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
229 _8c.html" target="source" name="BlurImage">BlurImage</a></h2>
230 <div class="doc-section">
232 <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>
234 <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>
236 <p>The format of the BlurImage method is:</p>
239 Image *BlurImage(const Image *image,const double radius,
240 const double sigma,ExceptionInfo *exception)
241 Image *BlurImageChannel(const Image *image,const ChannelType channel,
242 const double radius,const double sigma,ExceptionInfo *exception)
245 <p>A description of each parameter follows:</p></ol>
248 <ol><p>the image.</p></ol>
251 <ol><p>the channel type.</p></ol>
254 <ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
257 <ol><p>the standard deviation of the Gaussian, in pixels.</p></ol>
260 <ol><p>return any errors or warnings in this structure.</p></ol>
263 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
264 _8c.html" target="source" name="ConvolveImage">ConvolveImage</a></h2>
265 <div class="doc-section">
267 <p>ConvolveImage() applies a custom convolution kernel to the image.</p></ol>
269 <p>The format of the ConvolveImage method is:</p>
272 Image *ConvolveImage(const Image *image,const unsigned long order,
273 const double *kernel,ExceptionInfo *exception)
274 Image *ConvolveImageChannel(const Image *image,const ChannelType channel,
275 const unsigned long order,const double *kernel,
276 ExceptionInfo *exception)
279 <p>A description of each parameter follows:</p></ol>
282 <ol><p>the image.</p></ol>
285 <ol><p>the channel type.</p></ol>
288 <ol><p>the number of columns and rows in the filter kernel.</p></ol>
291 <ol><p>An array of double representing the convolution kernel.</p></ol>
294 <ol><p>return any errors or warnings in this structure.</p></ol>
297 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
298 _8c.html" target="source" name="DespeckleImage">DespeckleImage</a></h2>
299 <div class="doc-section">
301 <p>DespeckleImage() reduces the speckle noise in an image while perserving the edges of the original image.</p></ol>
303 <p>The format of the DespeckleImage method is:</p>
306 Image *DespeckleImage(const Image *image,ExceptionInfo *exception)
309 <p>A description of each parameter follows:</p></ol>
312 <ol><p>the image.</p></ol>
315 <ol><p>return any errors or warnings in this structure.</p></ol>
318 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
319 _8c.html" target="source" name="EdgeImage">EdgeImage</a></h2>
320 <div class="doc-section">
322 <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>
324 <p>The format of the EdgeImage method is:</p>
327 Image *EdgeImage(const Image *image,const double radius,
328 ExceptionInfo *exception)
331 <p>A description of each parameter follows:</p></ol>
334 <ol><p>the image.</p></ol>
337 <ol><p>the radius of the pixel neighborhood.</p></ol>
340 <ol><p>return any errors or warnings in this structure.</p></ol>
343 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
344 _8c.html" target="source" name="EmbossImage">EmbossImage</a></h2>
345 <div class="doc-section">
347 <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>
349 <p>The format of the EmbossImage method is:</p>
352 Image *EmbossImage(const Image *image,const double radius,
353 const double sigma,ExceptionInfo *exception)
356 <p>A description of each parameter follows:</p></ol>
359 <ol><p>the image.</p></ol>
362 <ol><p>the radius of the pixel neighborhood.</p></ol>
365 <ol><p>the standard deviation of the Gaussian, in pixels.</p></ol>
368 <ol><p>return any errors or warnings in this structure.</p></ol>
371 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
372 _8c.html" target="source" name="FilterImage">FilterImage</a></h2>
373 <div class="doc-section">
375 <p>FilterImage() applies a custom convolution kernel to the image.</p></ol>
377 <p>The format of the FilterImage method is:</p>
380 Image *FilterImage(const Image *image,const KernelInfo *kernel,
381 ExceptionInfo *exception)
382 Image *FilterImageChannel(const Image *image,const ChannelType channel,
383 const KernelInfo *kernel,ExceptionInfo *exception)
386 <p>A description of each parameter follows:</p></ol>
389 <ol><p>the image.</p></ol>
392 <ol><p>the channel type.</p></ol>
395 <ol><p>the filtering kernel.</p></ol>
398 <ol><p>return any errors or warnings in this structure.</p></ol>
401 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
402 _8c.html" target="source" name="GaussianBlurImage">GaussianBlurImage</a></h2>
403 <div class="doc-section">
405 <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>
407 <p>The format of the GaussianBlurImage method is:</p>
410 Image *GaussianBlurImage(const Image *image,onst double radius,
411 const double sigma,ExceptionInfo *exception)
412 Image *GaussianBlurImageChannel(const Image *image,
413 const ChannelType channel,const double radius,const double sigma,
414 ExceptionInfo *exception)
417 <p>A description of each parameter follows:</p></ol>
420 <ol><p>the image.</p></ol>
423 <ol><p>the channel type.</p></ol>
426 <ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
429 <ol><p>the standard deviation of the Gaussian, in pixels.</p></ol>
432 <ol><p>return any errors or warnings in this structure.</p></ol>
435 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
436 _8c.html" target="source" name="MedianFilterImage">MedianFilterImage</a></h2>
437 <div class="doc-section">
439 <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>
441 <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>
443 <p>The format of the MedianFilterImage method is:</p>
446 Image *MedianFilterImage(const Image *image,const double radius,
447 ExceptionInfo *exception)
450 <p>A description of each parameter follows:</p></ol>
453 <ol><p>the image.</p></ol>
456 <ol><p>the radius of the pixel neighborhood.</p></ol>
459 <ol><p>return any errors or warnings in this structure.</p></ol>
462 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
463 _8c.html" target="source" name="MotionBlurImage">MotionBlurImage</a></h2>
464 <div class="doc-section">
466 <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>
468 <p>Andrew Protano contributed this effect.</p></ol>
470 <p>The format of the MotionBlurImage method is:</p>
473 Image *MotionBlurImage(const Image *image,const double radius,
474 const double sigma,const double angle,ExceptionInfo *exception)
475 Image *MotionBlurImageChannel(const Image *image,const ChannelType channel,
476 const double radius,const double sigma,const double angle,
477 ExceptionInfo *exception)
480 <p>A description of each parameter follows:</p></ol>
483 <ol><p>the image.</p></ol>
486 <ol><p>the channel type.</p></ol>
489 <ol><p>the radius of the Gaussian, in pixels, not counting the center</p>
491 <ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
494 <ol><p>the standard deviation of the Gaussian, in pixels.</p></ol>
497 <ol><p>Apply the effect along this angle.</p></ol>
500 <ol><p>return any errors or warnings in this structure.</p></ol>
503 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
504 _8c.html" target="source" name="PreviewImage">PreviewImage</a></h2>
505 <div class="doc-section">
507 <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>
509 <p>The format of the PreviewImages method is:</p>
512 Image *PreviewImages(const Image *image,const PreviewType preview,
513 ExceptionInfo *exception)
516 <p>A description of each parameter follows:</p></ol>
519 <ol><p>the image.</p></ol>
522 <ol><p>the image processing operation.</p></ol>
525 <ol><p>return any errors or warnings in this structure.</p></ol>
528 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
529 _8c.html" target="source" name="RadialBlurImage">RadialBlurImage</a></h2>
530 <div class="doc-section">
532 <p>RadialBlurImage() applies a radial blur to the image.</p></ol>
534 <p>Andrew Protano contributed this effect.</p></ol>
536 <p>The format of the RadialBlurImage method is:</p>
539 Image *RadialBlurImage(const Image *image,const double angle,
540 ExceptionInfo *exception)
541 Image *RadialBlurImageChannel(const Image *image,const ChannelType channel,
542 const double angle,ExceptionInfo *exception)
545 <p>A description of each parameter follows:</p></ol>
548 <ol><p>the image.</p></ol>
551 <ol><p>the channel type.</p></ol>
554 <ol><p>the angle of the radial blur.</p></ol>
557 <ol><p>return any errors or warnings in this structure.</p></ol>
560 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
561 _8c.html" target="source" name="ReduceNoiseImage">ReduceNoiseImage</a></h2>
562 <div class="doc-section">
564 <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>
566 <p>The format of the ReduceNoiseImage method is:</p>
569 Image *ReduceNoiseImage(const Image *image,const double radius,
570 ExceptionInfo *exception)
573 <p>A description of each parameter follows:</p></ol>
576 <ol><p>the image.</p></ol>
579 <ol><p>the radius of the pixel neighborhood.</p></ol>
582 <ol><p>return any errors or warnings in this structure.</p></ol>
585 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
586 _8c.html" target="source" name="SelectiveBlurImage">SelectiveBlurImage</a></h2>
587 <div class="doc-section">
589 <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>
591 <p>The format of the SelectiveBlurImage method is:</p>
594 Image *SelectiveBlurImage(const Image *image,const double radius,
595 const double sigma,const double threshold,ExceptionInfo *exception)
596 Image *SelectiveBlurImageChannel(const Image *image,
597 const ChannelType channel,const double radius,const double sigma,
598 const double threshold,ExceptionInfo *exception)
601 <p>A description of each parameter follows:</p></ol>
604 <ol><p>the image.</p></ol>
607 <ol><p>the channel type.</p></ol>
610 <ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
613 <ol><p>the standard deviation of the Gaussian, in pixels.</p></ol>
616 <ol><p>only pixels within this contrast threshold are included in the blur operation.</p></ol>
619 <ol><p>return any errors or warnings in this structure.</p></ol>
622 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
623 _8c.html" target="source" name="ShadeImage">ShadeImage</a></h2>
624 <div class="doc-section">
626 <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>
628 <p>The format of the ShadeImage method is:</p>
631 Image *ShadeImage(const Image *image,const MagickBooleanType gray,
632 const double azimuth,const double elevation,ExceptionInfo *exception)
635 <p>A description of each parameter follows:</p></ol>
638 <ol><p>the image.</p></ol>
641 <ol><p>A value other than zero shades the intensity of each pixel.</p></ol>
643 <h5>azimuth, elevation</h5>
644 <ol><p>Define the light source direction.</p></ol>
647 <ol><p>return any errors or warnings in this structure.</p></ol>
650 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
651 _8c.html" target="source" name="SharpenImage">SharpenImage</a></h2>
652 <div class="doc-section">
654 <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>
656 <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>
658 <p>The format of the SharpenImage method is:</p>
661 Image *SharpenImage(const Image *image,const double radius,
662 const double sigma,ExceptionInfo *exception)
663 Image *SharpenImageChannel(const Image *image,const ChannelType channel,
664 const double radius,const double sigma,ExceptionInfo *exception)
667 <p>A description of each parameter follows:</p></ol>
670 <ol><p>the image.</p></ol>
673 <ol><p>the channel type.</p></ol>
676 <ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
679 <ol><p>the standard deviation of the Laplacian, in pixels.</p></ol>
682 <ol><p>return any errors or warnings in this structure.</p></ol>
685 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
686 _8c.html" target="source" name="SpreadImage">SpreadImage</a></h2>
687 <div class="doc-section">
689 <p>SpreadImage() is a special effects method that randomly displaces each pixel in a block defined by the radius parameter.</p></ol>
691 <p>The format of the SpreadImage method is:</p>
694 Image *SpreadImage(const Image *image,const double radius,
695 ExceptionInfo *exception)
698 <p>A description of each parameter follows:</p></ol>
701 <ol><p>the image.</p></ol>
704 <ol><p>Choose a random pixel in a neighborhood of this extent.</p></ol>
707 <ol><p>return any errors or warnings in this structure.</p></ol>
710 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
711 _8c.html" target="source" name="UnsharpMaskImage">UnsharpMaskImage</a></h2>
712 <div class="doc-section">
714 <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>
716 <p>The format of the UnsharpMaskImage method is:</p>
719 Image *UnsharpMaskImage(const Image *image,const double radius,
720 const double sigma,const double amount,const double threshold,
721 ExceptionInfo *exception)
722 Image *UnsharpMaskImageChannel(const Image *image,
723 const ChannelType channel,const double radius,const double sigma,
724 const double amount,const double threshold,ExceptionInfo *exception)
727 <p>A description of each parameter follows:</p></ol>
730 <ol><p>the image.</p></ol>
733 <ol><p>the channel type.</p></ol>
736 <ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
739 <ol><p>the standard deviation of the Gaussian, in pixels.</p></ol>
742 <ol><p>the percentage of the difference between the original and the blur image that is added back into the original.</p></ol>
745 <ol><p>the threshold in pixels needed to apply the diffence amount.</p></ol>
748 <ol><p>return any errors or warnings in this structure.</p></ol>
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