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83 </script> 84 85 </div> 86 87 <main class="container"> 88 <div class="magick-template"> 89<div class="magick-header"> 90<p class="text-center"><a href="effect.html#AdaptiveBlurImage">AdaptiveBlurImage</a> • <a href="effect.html#AdaptiveSharpenImage">AdaptiveSharpenImage</a> • <a href="effect.html#BlurImage">BlurImage</a> • <a href="effect.html#ConvolveImage">ConvolveImage</a> • <a href="effect.html#DespeckleImage">DespeckleImage</a> • <a href="effect.html#EdgeImage">EdgeImage</a> • <a href="effect.html#EmbossImage">EmbossImage</a> • <a href="effect.html#GaussianBlurImage">GaussianBlurImage</a> • <a href="effect.html#KuwaharaImage">KuwaharaImage</a> • <a href="effect.html#LocalContrastImage">LocalContrastImage</a> • <a href="effect.html#MotionBlurImage">MotionBlurImage</a> • <a href="effect.html#PreviewImage">PreviewImage</a> • <a href="effect.html#RotationalBlurImage">RotationalBlurImage</a> • <a href="effect.html#SelectiveBlurImage">SelectiveBlurImage</a> • <a href="effect.html#ShadeImage">ShadeImage</a> • <a href="effect.html#SharpenImage">SharpenImage</a> • <a href="effect.html#SpreadImage">SpreadImage</a> • <a href="effect.html#UnsharpMaskImage">UnsharpMaskImage</a></p> 91 92<h2><a href="../../api/MagickCore/effect_8c.html" id="AdaptiveBlurImage">AdaptiveBlurImage</a></h2> 93 94<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> 95 96<p>The format of the AdaptiveBlurImage method is:</p> 97 98<pre class="text"> 99Image *AdaptiveBlurImage(const Image *image,const double radius, 100 const double sigma,ExceptionInfo *exception) 101</pre> 102 103<p>A description of each parameter follows:</p> 104 105<dd> 106</dd> 107 108<dd> </dd> 109<dl class="dl-horizontal"> 110<dt>image</dt> 111<dd>the image. </dd> 112 113<dd> </dd> 114<dt>radius</dt> 115<dd>the radius of the Gaussian, in pixels, not counting the center pixel. </dd> 116 117<dd> </dd> 118<dt>sigma</dt> 119<dd>the standard deviation of the Laplacian, in pixels. </dd> 120 121<dd> </dd> 122<dt>exception</dt> 123<dd>return any errors or warnings in this structure. </dd> 124 125<dd> </dd> 126</dl> 127<h2><a href="../../api/MagickCore/effect_8c.html" id="AdaptiveSharpenImage">AdaptiveSharpenImage</a></h2> 128 129<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> 130 131<p>The format of the AdaptiveSharpenImage method is:</p> 132 133<pre class="text"> 134Image *AdaptiveSharpenImage(const Image *image,const double radius, 135 const double sigma,ExceptionInfo *exception) 136</pre> 137 138<p>A description of each parameter follows:</p> 139 140<dd> 141</dd> 142 143<dd> </dd> 144<dl class="dl-horizontal"> 145<dt>image</dt> 146<dd>the image. </dd> 147 148<dd> </dd> 149<dt>radius</dt> 150<dd>the radius of the Gaussian, in pixels, not counting the center pixel. </dd> 151 152<dd> </dd> 153<dt>sigma</dt> 154<dd>the standard deviation of the Laplacian, in pixels. </dd> 155 156<dd> </dd> 157<dt>exception</dt> 158<dd>return any errors or warnings in this structure. </dd> 159 160<dd> </dd> 161</dl> 162<h2><a href="../../api/MagickCore/effect_8c.html" id="BlurImage">BlurImage</a></h2> 163 164<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> 165 166<p>The format of the BlurImage method is:</p> 167 168<pre class="text"> 169Image *BlurImage(const Image *image,const double radius, 170 const double sigma,ExceptionInfo *exception) 171</pre> 172 173<p>A description of each parameter follows:</p> 174 175<dd> 176</dd> 177 178<dd> </dd> 179<dl class="dl-horizontal"> 180<dt>image</dt> 181<dd>the image. </dd> 182 183<dd> </dd> 184<dt>radius</dt> 185<dd>the radius of the Gaussian, in pixels, not counting the center pixel. </dd> 186 187<dd> </dd> 188<dt>sigma</dt> 189<dd>the standard deviation of the Gaussian, in pixels. </dd> 190 191<dd> </dd> 192<dt>exception</dt> 193<dd>return any errors or warnings in this structure. </dd> 194 195<dd> </dd> 196</dl> 197<h2><a href="../../api/MagickCore/effect_8c.html" id="ConvolveImage">ConvolveImage</a></h2> 198 199<p>ConvolveImage() applies a custom convolution kernel to the image.</p> 200 201<p>The format of the ConvolveImage method is:</p> 202 203<pre class="text"> 204Image *ConvolveImage(const Image *image,const KernelInfo *kernel, 205 ExceptionInfo *exception) 206</pre> 207 208<p>A description of each parameter follows:</p> 209 210<dd> 211</dd> 212 213<dd> </dd> 214<dl class="dl-horizontal"> 215<dt>image</dt> 216<dd>the image. </dd> 217 218<dd> </dd> 219<dt>kernel</dt> 220<dd>the filtering kernel. </dd> 221 222<dd> </dd> 223<dt>exception</dt> 224<dd>return any errors or warnings in this structure. </dd> 225 226<dd> </dd> 227</dl> 228<h2><a href="../../api/MagickCore/effect_8c.html" id="DespeckleImage">DespeckleImage</a></h2> 229 230<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> 231 232<p>The format of the DespeckleImage method is:</p> 233 234<pre class="text"> 235Image *DespeckleImage(const Image *image,ExceptionInfo *exception) 236</pre> 237 238<p>A description of each parameter follows:</p> 239 240<dd> 241</dd> 242 243<dd> </dd> 244<dl class="dl-horizontal"> 245<dt>image</dt> 246<dd>the image. </dd> 247 248<dd> </dd> 249<dt>exception</dt> 250<dd>return any errors or warnings in this structure. </dd> 251 252<dd> </dd> 253</dl> 254<h2><a href="../../api/MagickCore/effect_8c.html" id="EdgeImage">EdgeImage</a></h2> 255 256<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> 257 258<p>The format of the EdgeImage method is:</p> 259 260<pre class="text"> 261Image *EdgeImage(const Image *image,const double radius, 262 ExceptionInfo *exception) 263</pre> 264 265<p>A description of each parameter follows:</p> 266 267<dd> 268</dd> 269 270<dd> </dd> 271<dl class="dl-horizontal"> 272<dt>image</dt> 273<dd>the image. </dd> 274 275<dd> </dd> 276<dt>radius</dt> 277<dd>the radius of the pixel neighborhood. </dd> 278 279<dd> </dd> 280<dt>exception</dt> 281<dd>return any errors or warnings in this structure. </dd> 282 283<dd> </dd> 284</dl> 285<h2><a href="../../api/MagickCore/effect_8c.html" id="EmbossImage">EmbossImage</a></h2> 286 287<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> 288 289<p>The format of the EmbossImage method is:</p> 290 291<pre class="text"> 292Image *EmbossImage(const Image *image,const double radius, 293 const double sigma,ExceptionInfo *exception) 294</pre> 295 296<p>A description of each parameter follows:</p> 297 298<dd> 299</dd> 300 301<dd> </dd> 302<dl class="dl-horizontal"> 303<dt>image</dt> 304<dd>the image. </dd> 305 306<dd> </dd> 307<dt>radius</dt> 308<dd>the radius of the pixel neighborhood. </dd> 309 310<dd> </dd> 311<dt>sigma</dt> 312<dd>the standard deviation of the Gaussian, in pixels. </dd> 313 314<dd> </dd> 315<dt>exception</dt> 316<dd>return any errors or warnings in this structure. </dd> 317 318<dd> </dd> 319</dl> 320<h2><a href="../../api/MagickCore/effect_8c.html" id="GaussianBlurImage">GaussianBlurImage</a></h2> 321 322<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> 323 324<p>The format of the GaussianBlurImage method is:</p> 325 326<pre class="text"> 327Image *GaussianBlurImage(const Image *image,onst double radius, 328 const double sigma,ExceptionInfo *exception) 329</pre> 330 331<p>A description of each parameter follows:</p> 332 333<dd> 334</dd> 335 336<dd> </dd> 337<dl class="dl-horizontal"> 338<dt>image</dt> 339<dd>the image. </dd> 340 341<dd> </dd> 342<dt>radius</dt> 343<dd>the radius of the Gaussian, in pixels, not counting the center pixel. </dd> 344 345<dd> </dd> 346<dt>sigma</dt> 347<dd>the standard deviation of the Gaussian, in pixels. </dd> 348 349<dd> </dd> 350<dt>exception</dt> 351<dd>return any errors or warnings in this structure. </dd> 352 353<dd> </dd> 354</dl> 355<h2><a href="../../api/MagickCore/effect_8c.html" id="KuwaharaImage">KuwaharaImage</a></h2> 356 357<p>KuwaharaImage() is an edge preserving noise reduction filter.</p> 358 359<p>The format of the KuwaharaImage method is:</p> 360 361<pre class="text"> 362Image *KuwaharaImage(const Image *image,const double radius, 363 const double sigma,ExceptionInfo *exception) 364</pre> 365 366<p>A description of each parameter follows:</p> 367 368<dd> 369</dd> 370 371<dd> </dd> 372<dl class="dl-horizontal"> 373<dt>image</dt> 374<dd>the image. </dd> 375 376<dd> </dd> 377<dt>radius</dt> 378<dd>the square window radius. </dd> 379 380<dd> </dd> 381<dt>sigma</dt> 382<dd>the standard deviation of the Gaussian, in pixels. </dd> 383 384<dd> </dd> 385<dt>exception</dt> 386<dd>return any errors or warnings in this structure. </dd> 387 388<dd> </dd> 389</dl> 390<h2><a href="../../api/MagickCore/effect_8c.html" id="LocalContrastImage">LocalContrastImage</a></h2> 391 392<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> 393 394<p>The format of the LocalContrastImage method is:</p> 395 396<pre class="text"> 397Image *LocalContrastImage(const Image *image, const double radius, 398 const double strength,ExceptionInfo *exception) 399</pre> 400 401<p>A description of each parameter follows:</p> 402 403<dd> 404</dd> 405 406<dd> </dd> 407<dl class="dl-horizontal"> 408<dt>image</dt> 409<dd>the image. </dd> 410 411<dd> </dd> 412<dt>radius</dt> 413<dd>the radius of the Gaussian blur, in percentage with 100 resulting in a blur radius of 20 of largest dimension. </dd> 414 415<dd> </dd> 416<dt>strength</dt> 417<dd>the strength of the blur mask in percentage. </dd> 418 419<dd> </dd> 420<dt>exception</dt> 421<dd>return any errors or warnings in this structure. </dd> 422 423<dd> </dd> 424</dl> 425<h2><a href="../../api/MagickCore/effect_8c.html" id="MotionBlurImage">MotionBlurImage</a></h2> 426 427<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> 428 429<p>Andrew Protano contributed this effect.</p> 430 431<p>The format of the MotionBlurImage method is:</p> 432 433<pre class="text"> 434 Image *MotionBlurImage(const Image *image,const double radius, 435const double sigma,const double angle,ExceptionInfo *exception) 436</pre> 437 438<p>A description of each parameter follows:</p> 439 440<dd> 441</dd> 442 443<dd> </dd> 444<dl class="dl-horizontal"> 445<dt>image</dt> 446<dd>the image. </dd> 447 448<dd> </dd> 449<dt>radius</dt> 450<dd>the radius of the Gaussian, in pixels, not counting the center pixel. </dd> 451 452<dd> </dd> 453<dt>sigma</dt> 454<dd>the standard deviation of the Gaussian, in pixels. </dd> 455 456<dd> </dd> 457<dt>angle</dt> 458<dd>Apply the effect along this angle. </dd> 459 460<dd> </dd> 461<dt>exception</dt> 462<dd>return any errors or warnings in this structure. </dd> 463 464<dd> </dd> 465</dl> 466<h2><a href="../../api/MagickCore/effect_8c.html" id="PreviewImage">PreviewImage</a></h2> 467 468<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> 469 470<p>The format of the PreviewImages method is:</p> 471 472<pre class="text"> 473Image *PreviewImages(const Image *image,const PreviewType preview, 474 ExceptionInfo *exception) 475</pre> 476 477<p>A description of each parameter follows:</p> 478 479<dd> 480</dd> 481 482<dd> </dd> 483<dl class="dl-horizontal"> 484<dt>image</dt> 485<dd>the image. </dd> 486 487<dd> </dd> 488<dt>preview</dt> 489<dd>the image processing operation. </dd> 490 491<dd> </dd> 492<dt>exception</dt> 493<dd>return any errors or warnings in this structure. </dd> 494 495<dd> </dd> 496</dl> 497<h2><a href="../../api/MagickCore/effect_8c.html" id="RotationalBlurImage">RotationalBlurImage</a></h2> 498 499<p>RotationalBlurImage() applies a radial blur to the image.</p> 500 501<p>Andrew Protano contributed this effect.</p> 502 503<p>The format of the RotationalBlurImage method is:</p> 504 505<pre class="text"> 506 Image *RotationalBlurImage(const Image *image,const double angle, 507ExceptionInfo *exception) 508</pre> 509 510<p>A description of each parameter follows:</p> 511 512<dd> 513</dd> 514 515<dd> </dd> 516<dl class="dl-horizontal"> 517<dt>image</dt> 518<dd>the image. </dd> 519 520<dd> </dd> 521<dt>angle</dt> 522<dd>the angle of the radial blur. </dd> 523 524<dd> </dd> 525<dt>blur</dt> 526<dd>the blur. </dd> 527 528<dd> </dd> 529<dt>exception</dt> 530<dd>return any errors or warnings in this structure. </dd> 531 532<dd> </dd> 533</dl> 534<h2><a href="../../api/MagickCore/effect_8c.html" id="SelectiveBlurImage">SelectiveBlurImage</a></h2> 535 536<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> 537 538<p>The format of the SelectiveBlurImage method is:</p> 539 540<pre class="text"> 541Image *SelectiveBlurImage(const Image *image,const double radius, 542 const double sigma,const double threshold,ExceptionInfo *exception) 543</pre> 544 545<p>A description of each parameter follows:</p> 546 547<dd> 548</dd> 549 550<dd> </dd> 551<dl class="dl-horizontal"> 552<dt>image</dt> 553<dd>the image. </dd> 554 555<dd> </dd> 556<dt>radius</dt> 557<dd>the radius of the Gaussian, in pixels, not counting the center pixel. </dd> 558 559<dd> </dd> 560<dt>sigma</dt> 561<dd>the standard deviation of the Gaussian, in pixels. </dd> 562 563<dd> </dd> 564<dt>threshold</dt> 565<dd>only pixels within this contrast threshold are included in the blur operation. </dd> 566 567<dd> </dd> 568<dt>exception</dt> 569<dd>return any errors or warnings in this structure. </dd> 570 571<dd> </dd> 572</dl> 573<h2><a href="../../api/MagickCore/effect_8c.html" id="ShadeImage">ShadeImage</a></h2> 574 575<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> 576 577<p>The format of the ShadeImage method is:</p> 578 579<pre class="text"> 580Image *ShadeImage(const Image *image,const MagickBooleanType gray, 581 const double azimuth,const double elevation,ExceptionInfo *exception) 582</pre> 583 584<p>A description of each parameter follows:</p> 585 586<dd> 587</dd> 588 589<dd> </dd> 590<dl class="dl-horizontal"> 591<dt>image</dt> 592<dd>the image. </dd> 593 594<dd> </dd> 595<dt>gray</dt> 596<dd>A value other than zero shades the intensity of each pixel. </dd> 597 598<dd> </dd> 599<dt>azimuth, elevation</dt> 600<dd> Define the light source direction. </dd> 601 602<dd> </dd> 603<dt>exception</dt> 604<dd>return any errors or warnings in this structure. </dd> 605 606<dd> </dd> 607</dl> 608<h2><a href="../../api/MagickCore/effect_8c.html" id="SharpenImage">SharpenImage</a></h2> 609 610<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> 611 612<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> 613 614<p>The format of the SharpenImage method is:</p> 615 616<pre class="text"> 617 Image *SharpenImage(const Image *image,const double radius, 618const double sigma,ExceptionInfo *exception) 619</pre> 620 621<p>A description of each parameter follows:</p> 622 623<dd> 624</dd> 625 626<dd> </dd> 627<dl class="dl-horizontal"> 628<dt>image</dt> 629<dd>the image. </dd> 630 631<dd> </dd> 632<dt>radius</dt> 633<dd>the radius of the Gaussian, in pixels, not counting the center pixel. </dd> 634 635<dd> </dd> 636<dt>sigma</dt> 637<dd>the standard deviation of the Laplacian, in pixels. </dd> 638 639<dd> </dd> 640<dt>exception</dt> 641<dd>return any errors or warnings in this structure. </dd> 642 643<dd> </dd> 644</dl> 645<h2><a href="../../api/MagickCore/effect_8c.html" id="SpreadImage">SpreadImage</a></h2> 646 647<p>SpreadImage() is a special effects method that randomly displaces each pixel in a square area defined by the radius parameter.</p> 648 649<p>The format of the SpreadImage method is:</p> 650 651<pre class="text"> 652Image *SpreadImage(const Image *image, 653 const PixelInterpolateMethod method,const double radius, 654 ExceptionInfo *exception) 655</pre> 656 657<p>A description of each parameter follows:</p> 658 659<dd> 660</dd> 661 662<dd> </dd> 663<dl class="dl-horizontal"> 664<dt>image</dt> 665<dd>the image. </dd> 666 667<dd> </dd> 668<dt>method</dt> 669<dd> intepolation method. </dd> 670 671<dd> </dd> 672<dt>radius</dt> 673<dd> choose a random pixel in a neighborhood of this extent. </dd> 674 675<dd> </dd> 676<dt>exception</dt> 677<dd>return any errors or warnings in this structure. </dd> 678 679<dd> </dd> 680</dl> 681<h2><a href="../../api/MagickCore/effect_8c.html" id="UnsharpMaskImage">UnsharpMaskImage</a></h2> 682 683<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> 684 685<p>The format of the UnsharpMaskImage method is:</p> 686 687<pre class="text"> 688 Image *UnsharpMaskImage(const Image *image,const double radius, 689const double sigma,const double amount,const double threshold, 690ExceptionInfo *exception) 691</pre> 692 693<p>A description of each parameter follows:</p> 694 695<dd> 696</dd> 697 698<dd> </dd> 699<dl class="dl-horizontal"> 700<dt>image</dt> 701<dd>the image. </dd> 702 703<dd> </dd> 704<dt>radius</dt> 705<dd>the radius of the Gaussian, in pixels, not counting the center pixel. </dd> 706 707<dd> </dd> 708<dt>sigma</dt> 709<dd>the standard deviation of the Gaussian, in pixels. </dd> 710 711<dd> </dd> 712<dt>gain</dt> 713<dd>the percentage of the difference between the original and the blur image that is added back into the original. </dd> 714 715<dd> </dd> 716<dt>threshold</dt> 717<dd>the threshold in pixels needed to apply the diffence gain. </dd> 718 719<dd> </dd> 720<dt>exception</dt> 721<dd>return any errors or warnings in this structure. </dd> 722 723<dd> </dd> 724</dl> 725</div> 726 </div> 727 </main><!-- /.container --> 728 <footer class="magick-footer"> 729 <p><a href="../../www/security-policy.html">Security</a> • 730 <a href="../../www/architecture.html">Architecture</a> 731 732 <a href="effect.html#"><img class="d-inline" id="wand" alt="And Now a Touch of Magick" width="16" height="16" src="../../images/wand.ico"/></a> 733 734 <a href="../../www/links.html">Related</a> • 735 <a href="../../www/sitemap.html">Sitemap</a> 736 <br/> 737 <a href="../../www/support.html">Donate</a> • 738 <a href="http://pgp.mit.edu/pks/lookup?op=get&search=0x89AB63D48277377A">Public Key</a> • 739 <a href="../../www/contact.html">Contact Us</a> 740 <br/> 741 <small>© 1999-2020 ImageMagick Studio LLC</small></p> 742 </footer> 743 744 <!-- Javascript assets --> 745 <script src="../assets/magick.js" crossorigin="anonymous"></script> 746 <script>window.jQuery || document.write('<script src="https://localhost/ajax/libs/jquery/3.4.1/jquery.min.js"><\/script>')</script> 747</body> 748</html> 749<!-- Magick Cache 5th January 2020 00:27 -->
