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155 <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>
157 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
158 _8c.html" target="source" name="AdaptiveBlurImage">AdaptiveBlurImage</a></h2>
159 <div class="doc-section">
161 <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>
163 <p>The format of the AdaptiveBlurImage method is:</p>
166 Image *AdaptiveBlurImage(const Image *image,const double radius,
167 const double sigma,ExceptionInfo *exception)
168 Image *AdaptiveBlurImageChannel(const Image *image,
169 const ChannelType channel,double radius,const double sigma,
170 ExceptionInfo *exception)
173 <p>A description of each parameter follows:</p></ol>
176 <ol><p>the image.</p></ol>
179 <ol><p>the channel type.</p></ol>
182 <ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
185 <ol><p>the standard deviation of the Laplacian, in pixels.</p></ol>
188 <ol><p>return any errors or warnings in this structure.</p></ol>
191 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
192 _8c.html" target="source" name="AdaptiveSharpenImage">AdaptiveSharpenImage</a></h2>
193 <div class="doc-section">
195 <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>
197 <p>The format of the AdaptiveSharpenImage method is:</p>
200 Image *AdaptiveSharpenImage(const Image *image,const double radius,
201 const double sigma,ExceptionInfo *exception)
202 Image *AdaptiveSharpenImageChannel(const Image *image,
203 const ChannelType channel,double radius,const double sigma,
204 ExceptionInfo *exception)
207 <p>A description of each parameter follows:</p></ol>
210 <ol><p>the image.</p></ol>
213 <ol><p>the channel type.</p></ol>
216 <ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
219 <ol><p>the standard deviation of the Laplacian, in pixels.</p></ol>
222 <ol><p>return any errors or warnings in this structure.</p></ol>
225 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
226 _8c.html" target="source" name="BlurImage">BlurImage</a></h2>
227 <div class="doc-section">
229 <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>
231 <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>
233 <p>The format of the BlurImage method is:</p>
236 Image *BlurImage(const Image *image,const double radius,
237 const double sigma,ExceptionInfo *exception)
238 Image *BlurImageChannel(const Image *image,const ChannelType channel,
239 const double radius,const double sigma,ExceptionInfo *exception)
242 <p>A description of each parameter follows:</p></ol>
245 <ol><p>the image.</p></ol>
248 <ol><p>the channel type.</p></ol>
251 <ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
254 <ol><p>the standard deviation of the Gaussian, in pixels.</p></ol>
257 <ol><p>return any errors or warnings in this structure.</p></ol>
260 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
261 _8c.html" target="source" name="ConvolveImage">ConvolveImage</a></h2>
262 <div class="doc-section">
264 <p>ConvolveImage() applies a custom convolution kernel to the image.</p></ol>
266 <p>The format of the ConvolveImage method is:</p>
269 Image *ConvolveImage(const Image *image,const unsigned long order,
270 const double *kernel,ExceptionInfo *exception)
271 Image *ConvolveImageChannel(const Image *image,const ChannelType channel,
272 const unsigned long order,const double *kernel,
273 ExceptionInfo *exception)
276 <p>A description of each parameter follows:</p></ol>
279 <ol><p>the image.</p></ol>
282 <ol><p>the channel type.</p></ol>
285 <ol><p>the number of columns and rows in the filter kernel.</p></ol>
288 <ol><p>An array of double representing the convolution kernel.</p></ol>
291 <ol><p>return any errors or warnings in this structure.</p></ol>
294 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
295 _8c.html" target="source" name="DespeckleImage">DespeckleImage</a></h2>
296 <div class="doc-section">
298 <p>DespeckleImage() reduces the speckle noise in an image while perserving the edges of the original image.</p></ol>
300 <p>The format of the DespeckleImage method is:</p>
303 Image *DespeckleImage(const Image *image,ExceptionInfo *exception)
306 <p>A description of each parameter follows:</p></ol>
309 <ol><p>the image.</p></ol>
312 <ol><p>return any errors or warnings in this structure.</p></ol>
315 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
316 _8c.html" target="source" name="EdgeImage">EdgeImage</a></h2>
317 <div class="doc-section">
319 <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>
321 <p>The format of the EdgeImage method is:</p>
324 Image *EdgeImage(const Image *image,const double radius,
325 ExceptionInfo *exception)
328 <p>A description of each parameter follows:</p></ol>
331 <ol><p>the image.</p></ol>
334 <ol><p>the radius of the pixel neighborhood.</p></ol>
337 <ol><p>return any errors or warnings in this structure.</p></ol>
340 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
341 _8c.html" target="source" name="EmbossImage">EmbossImage</a></h2>
342 <div class="doc-section">
344 <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>
346 <p>The format of the EmbossImage method is:</p>
349 Image *EmbossImage(const Image *image,const double radius,
350 const double sigma,ExceptionInfo *exception)
353 <p>A description of each parameter follows:</p></ol>
356 <ol><p>the image.</p></ol>
359 <ol><p>the radius of the pixel neighborhood.</p></ol>
362 <ol><p>the standard deviation of the Gaussian, in pixels.</p></ol>
365 <ol><p>return any errors or warnings in this structure.</p></ol>
368 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
369 _8c.html" target="source" name="FilterImage">FilterImage</a></h2>
370 <div class="doc-section">
372 <p>FilterImage() applies a custom convolution kernel to the image.</p></ol>
374 <p>The format of the FilterImage method is:</p>
377 Image *FilterImage(const Image *image,const KernelInfo *kernel,
378 ExceptionInfo *exception)
379 Image *FilterImageChannel(const Image *image,const ChannelType channel,
380 const KernelInfo *kernel,ExceptionInfo *exception)
383 <p>A description of each parameter follows:</p></ol>
386 <ol><p>the image.</p></ol>
389 <ol><p>the channel type.</p></ol>
392 <ol><p>the filtering kernel.</p></ol>
395 <ol><p>return any errors or warnings in this structure.</p></ol>
398 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
399 _8c.html" target="source" name="GaussianBlurImage">GaussianBlurImage</a></h2>
400 <div class="doc-section">
402 <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>
404 <p>The format of the GaussianBlurImage method is:</p>
407 Image *GaussianBlurImage(const Image *image,onst double radius,
408 const double sigma,ExceptionInfo *exception)
409 Image *GaussianBlurImageChannel(const Image *image,
410 const ChannelType channel,const double radius,const double sigma,
411 ExceptionInfo *exception)
414 <p>A description of each parameter follows:</p></ol>
417 <ol><p>the image.</p></ol>
420 <ol><p>the channel type.</p></ol>
423 <ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
426 <ol><p>the standard deviation of the Gaussian, in pixels.</p></ol>
429 <ol><p>return any errors or warnings in this structure.</p></ol>
432 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
433 _8c.html" target="source" name="MedianFilterImage">MedianFilterImage</a></h2>
434 <div class="doc-section">
436 <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>
438 <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>
440 <p>The format of the MedianFilterImage method is:</p>
443 Image *MedianFilterImage(const Image *image,const double radius,
444 ExceptionInfo *exception)
447 <p>A description of each parameter follows:</p></ol>
450 <ol><p>the image.</p></ol>
453 <ol><p>the radius of the pixel neighborhood.</p></ol>
456 <ol><p>return any errors or warnings in this structure.</p></ol>
459 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
460 _8c.html" target="source" name="MotionBlurImage">MotionBlurImage</a></h2>
461 <div class="doc-section">
463 <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>
465 <p>Andrew Protano contributed this effect.</p></ol>
467 <p>The format of the MotionBlurImage method is:</p>
470 Image *MotionBlurImage(const Image *image,const double radius,
471 const double sigma,const double angle,ExceptionInfo *exception)
472 Image *MotionBlurImageChannel(const Image *image,const ChannelType channel,
473 const double radius,const double sigma,const double angle,
474 ExceptionInfo *exception)
477 <p>A description of each parameter follows:</p></ol>
480 <ol><p>the image.</p></ol>
483 <ol><p>the channel type.</p></ol>
486 <ol><p>the radius of the Gaussian, in pixels, not counting the center</p>
488 <ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
491 <ol><p>the standard deviation of the Gaussian, in pixels.</p></ol>
494 <ol><p>Apply the effect along this angle.</p></ol>
497 <ol><p>return any errors or warnings in this structure.</p></ol>
500 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
501 _8c.html" target="source" name="PreviewImage">PreviewImage</a></h2>
502 <div class="doc-section">
504 <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>
506 <p>The format of the PreviewImages method is:</p>
509 Image *PreviewImages(const Image *image,const PreviewType preview,
510 ExceptionInfo *exception)
513 <p>A description of each parameter follows:</p></ol>
516 <ol><p>the image.</p></ol>
519 <ol><p>the image processing operation.</p></ol>
522 <ol><p>return any errors or warnings in this structure.</p></ol>
525 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
526 _8c.html" target="source" name="RadialBlurImage">RadialBlurImage</a></h2>
527 <div class="doc-section">
529 <p>RadialBlurImage() applies a radial blur to the image.</p></ol>
531 <p>Andrew Protano contributed this effect.</p></ol>
533 <p>The format of the RadialBlurImage method is:</p>
536 Image *RadialBlurImage(const Image *image,const double angle,
537 ExceptionInfo *exception)
538 Image *RadialBlurImageChannel(const Image *image,const ChannelType channel,
539 const double angle,ExceptionInfo *exception)
542 <p>A description of each parameter follows:</p></ol>
545 <ol><p>the image.</p></ol>
548 <ol><p>the channel type.</p></ol>
551 <ol><p>the angle of the radial blur.</p></ol>
554 <ol><p>return any errors or warnings in this structure.</p></ol>
557 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
558 _8c.html" target="source" name="ReduceNoiseImage">ReduceNoiseImage</a></h2>
559 <div class="doc-section">
561 <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>
563 <p>The format of the ReduceNoiseImage method is:</p>
566 Image *ReduceNoiseImage(const Image *image,const double radius,
567 ExceptionInfo *exception)
570 <p>A description of each parameter follows:</p></ol>
573 <ol><p>the image.</p></ol>
576 <ol><p>the radius of the pixel neighborhood.</p></ol>
579 <ol><p>return any errors or warnings in this structure.</p></ol>
582 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
583 _8c.html" target="source" name="SelectiveBlurImage">SelectiveBlurImage</a></h2>
584 <div class="doc-section">
586 <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>
588 <p>The format of the SelectiveBlurImage method is:</p>
591 Image *SelectiveBlurImage(const Image *image,const double radius,
592 const double sigma,const double threshold,ExceptionInfo *exception)
593 Image *SelectiveBlurImageChannel(const Image *image,
594 const ChannelType channel,const double radius,const double sigma,
595 const double threshold,ExceptionInfo *exception)
598 <p>A description of each parameter follows:</p></ol>
601 <ol><p>the image.</p></ol>
604 <ol><p>the channel type.</p></ol>
607 <ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
610 <ol><p>the standard deviation of the Gaussian, in pixels.</p></ol>
613 <ol><p>only pixels within this contrast threshold are included in the blur operation.</p></ol>
616 <ol><p>return any errors or warnings in this structure.</p></ol>
619 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
620 _8c.html" target="source" name="ShadeImage">ShadeImage</a></h2>
621 <div class="doc-section">
623 <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>
625 <p>The format of the ShadeImage method is:</p>
628 Image *ShadeImage(const Image *image,const MagickBooleanType gray,
629 const double azimuth,const double elevation,ExceptionInfo *exception)
632 <p>A description of each parameter follows:</p></ol>
635 <ol><p>the image.</p></ol>
638 <ol><p>A value other than zero shades the intensity of each pixel.</p></ol>
640 <h5>azimuth, elevation</h5>
641 <ol><p>Define the light source direction.</p></ol>
644 <ol><p>return any errors or warnings in this structure.</p></ol>
647 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
648 _8c.html" target="source" name="SharpenImage">SharpenImage</a></h2>
649 <div class="doc-section">
651 <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>
653 <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>
655 <p>The format of the SharpenImage method is:</p>
658 Image *SharpenImage(const Image *image,const double radius,
659 const double sigma,ExceptionInfo *exception)
660 Image *SharpenImageChannel(const Image *image,const ChannelType channel,
661 const double radius,const double sigma,ExceptionInfo *exception)
664 <p>A description of each parameter follows:</p></ol>
667 <ol><p>the image.</p></ol>
670 <ol><p>the channel type.</p></ol>
673 <ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
676 <ol><p>the standard deviation of the Laplacian, in pixels.</p></ol>
679 <ol><p>return any errors or warnings in this structure.</p></ol>
682 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
683 _8c.html" target="source" name="SpreadImage">SpreadImage</a></h2>
684 <div class="doc-section">
686 <p>SpreadImage() is a special effects method that randomly displaces each pixel in a block defined by the radius parameter.</p></ol>
688 <p>The format of the SpreadImage method is:</p>
691 Image *SpreadImage(const Image *image,const double radius,
692 ExceptionInfo *exception)
695 <p>A description of each parameter follows:</p></ol>
698 <ol><p>the image.</p></ol>
701 <ol><p>Choose a random pixel in a neighborhood of this extent.</p></ol>
704 <ol><p>return any errors or warnings in this structure.</p></ol>
707 <h2><a href="http://www.imagemagick.org/api/MagickCore/effect
708 _8c.html" target="source" name="UnsharpMaskImage">UnsharpMaskImage</a></h2>
709 <div class="doc-section">
711 <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>
713 <p>The format of the UnsharpMaskImage method is:</p>
716 Image *UnsharpMaskImage(const Image *image,const double radius,
717 const double sigma,const double amount,const double threshold,
718 ExceptionInfo *exception)
719 Image *UnsharpMaskImageChannel(const Image *image,
720 const ChannelType channel,const double radius,const double sigma,
721 const double amount,const double threshold,ExceptionInfo *exception)
724 <p>A description of each parameter follows:</p></ol>
727 <ol><p>the image.</p></ol>
730 <ol><p>the channel type.</p></ol>
733 <ol><p>the radius of the Gaussian, in pixels, not counting the center pixel.</p></ol>
736 <ol><p>the standard deviation of the Gaussian, in pixels.</p></ol>
739 <ol><p>the percentage of the difference between the original and the blur image that is added back into the original.</p></ol>
742 <ol><p>the threshold in pixels needed to apply the diffence amount.</p></ol>
745 <ol><p>return any errors or warnings in this structure.</p></ol>
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