1 2 3 4 5<!DOCTYPE html> 6<html lang="en"> 7<head> 8 <title>ImageMagick: MagickCore, Low-level C API for ImageMagick</title> 9 <meta charset="utf-8" /> 10 <meta http-equiv="X-UA-Compatible" content="IE=edge" /> 11 <meta name="viewport" content="width=device-width, initial-scale=1" /> 12 <meta http-equiv="content-type" content="text/html; charset=utf-8"/> 13 <meta name="application-name" content="ImageMagick"/> 14 <meta name="description" content="ImageMagick® is a software suite to create, edit, compose, or convert bitmap images. It can read and write images in a variety of formats (over 200) including PNG, JPEG, JPEG-2000, GIF, WebP, Postscript, PDF, and SVG. 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Unlike the <a href="magick-wand.html">MagickWand</a> C API which uses only a few opaque types and accessors, with MagickCore you almost exlusively access the structure members directly. A description of the MagickCore public methods are found here:</p> 61 62<ul> 63 <li><a href="api/magick.html">Initialize or Destroy the ImageMagick Environment</a></li> 64 <li><a href="api/constitute.html">Constitute an Image</a></li> 65 <li><a href="api/composite.html">Composite an Image</a></li> 66 <li><a href="api/image.html">Image Methods</a></li> 67 <li><a href="api/channel.html">Image Channel Methods</a></li> 68 <li><a href="api/color.html">Count the Colors in an Image</a></li> 69 <li><a href="api/colormap.html">Colormap Methods</a></li> 70 <li><a href="api/colorspace.html">Colorspace Methods</a></li> 71 <li><a href="api/distort.html">Image Distortions</a></li> 72 <li><a href="api/layer.html">Dealing with Image Layers</a></li> 73 <li><a href="api/profile.html">Dealing with Image Profiles</a></li> 74 <li><a href="api/quantize.html">Reduce the Number of Unique Colors in an Image</a></li> 75 <li><a href="api/histogram.html">Image Histograms</a></li> 76 <li><a href="api/segment.html">Segment an Image with Thresholding Fuzzy c-Means</a></li> 77 <li><a href="api/resize.html">Resize an Image</a></li> 78 <li><a href="api/transform.html">Transform an Image</a></li> 79 <li><a href="api/shear.html">Shear or Rotate an Image by an Arbitrary Angle</a></li> 80 <li><a href="api/enhance.html">Enhance an Image</a></li> 81 <li><a href="api/effect.html">Add an Effect</a></li> 82 <li><a href="api/morphology.html">Morphological Erosions, Dilations, Openings, and Closings</a></li> 83 <li><a href="api/fx.html">Add a Special Effect</a></li> 84 <li><a href="api/decorate.html">Decorate an Image</a></li> 85 <li><a href="api/attribute.html">Get/Set an Image Attribute</a></li> 86 <li><a href="api/property.html">Get/Set Image Properties</a></li> 87 <li><a href="api/statistic.html">Get Image Statistics</a></li> 88 <li><a href="api/feature.html">Get Image Features</a></li> 89 <li><a href="api/annotate.html">Annotate an Image</a></li> 90 <li><a href="api/paint.html">Paint on an Image</a></li> 91 <li><a href="api/draw.html">Draw on an Image</a></li> 92 <li><a href="api/montage.html">Create an Image Thumbnail</a></li> 93 <li><a href="api/fourier.html">Compute the discrete Fourier transform (DFT)</a></li> 94 <li><a href="api/compare.html">Compare an Image to a Reconstructed Image</a></li> 95 <li><a href="api/display.html">Interactively Display and Edit an Image</a></li> 96 <li><a href="api/animate.html">Interactively Animate an Image Sequence</a></li> 97 <li><a href="api/cipher.html">Convert to and from Cipher Pixels</a></li> 98 <li><a href="api/list.html">Working with Image Lists</a></li> 99 <li><a href="api/image-view.html">Image View Methods</a></li> 100 <li><a href="api/cache.html">Get or Set Image Pixels</a></li> 101 <li><a href="api/cache-view.html">Working with Cache Views</a></li> 102 <li><a href="api/stream.html">The Pixel FIFO</a></li> 103 <li><a href="api/blob.html">Read or Write Binary Large OBjects</a></li> 104 <li><a href="api/module.html">Loadable Modules</a></li> 105 <li><a href="api/signature.html">Compute a Message Digest for an Image</a></li> 106 <li><a href="api/registry.html">The Image Registry</a></li> 107 <li><a href="api/exception.html">Dealing with Exceptions</a></li> 108 <li><a href="api/memory.html">Memory Allocation</a></li> 109 <li><a href="api/resource.html">Monitor or Limit Resource Consumption</a></li> 110 <li><a href="api/monitor.html">Monitor the Progress of an Image Operation</a></li> 111 <li><a href="api/version.html">Get the Version and Copyrights</a></li> 112 <li><a href="api/mime.html">Mime Methods</a></li> 113 <li><a href="api/deprecate.html">Deprecated Methods</a></li> 114 <li><a href="exception.html">Error and Warning Codes</a></li> 115</ul> 116 117<p>After you write your MagickCore program, compile it like this:</p> 118 119<pre> 120cc -o core core.c `pkg-config --cflags --libs MagickCore` 121</pre> 122 123<p>Note, if your instance of ImageMagick does not support modules but does include support for the WMF image format, you'll need to link with the <a href="magick-wand.html">MagickWand</a> library instead (since it is a dependency of the WMF image format):</p> 124 125<pre> 126cc -o core core.c `pkg-config --cflags --libs MagickWand` 127</pre> 128 129<p>Set the <code>PKG_CONFIG_PATH</code> environment variable if ImageMagick is not in your default system path:</p> 130 131<pre> 132export PKG_CONFIG_PATH=/usr/local/lib/pkgconfig 133</pre> 134 135<p>Here is a example program that utilizes the MagickCore API to get you started, <a href="../source/core.c">core.c</a>. It reads a GIF image, creates a thumbnail, and writes it to disk in the PNG image format.</p> 136 137<pre class="pre-scrollable">#include <stdio.h> 138#include <stdlib.h> 139#include <string.h> 140#include <time.h> 141#include <magick/MagickCore.h> 142 143int main(int argc,char **argv) 144{ 145 ExceptionInfo 146 *exception; 147 148 Image 149 *image, 150 *images, 151 *resize_image, 152 *thumbnails; 153 154 ImageInfo 155 *image_info; 156 157 if (argc != 3) 158 { 159 (void) fprintf(stdout,"Usage: %s image thumbnail\n",argv[0]); 160 exit(0); 161 } 162 /* 163 Initialize the image info structure and read an image. 164 */ 165 MagickCoreGenesis(*argv,MagickTrue); 166 exception=AcquireExceptionInfo(); 167 image_info=CloneImageInfo((ImageInfo *) NULL); 168 (void) strcpy(image_info->filename,argv[1]); 169 images=ReadImage(image_info,exception); 170 if (exception->severity != UndefinedException) 171 CatchException(exception); 172 if (images == (Image *) NULL) 173 exit(1); 174 /* 175 Convert the image to a thumbnail. 176 */ 177 thumbnails=NewImageList(); 178 while ((image=RemoveFirstImageFromList(&images)) != (Image *) NULL) 179 { 180 resize_image=ResizeImage(image,106,80,LanczosFilter,1.0,exception); 181 if (resize_image == (Image *) NULL) 182 MagickError(exception->severity,exception->reason,exception->description); 183 (void) AppendImageToList(&thumbnails,resize_image); 184 DestroyImage(image); 185 } 186 /* 187 Write the image thumbnail. 188 */ 189 (void) strcpy(thumbnails->filename,argv[2]); 190 WriteImage(image_info,thumbnails); 191 /* 192 Destroy the image thumbnail and exit. 193 */ 194 thumbnails=DestroyImageList(thumbnails); 195 image_info=DestroyImageInfo(image_info); 196 exception=DestroyExceptionInfo(exception); 197 MagickCoreTerminus(); 198 return(0); 199}</pre> 200<p><a id="image-view"></a>Now lets perform the same contrast enhancement while taking advantage of our dual or quad-core processing system by running the algorithm in parallel utilizing wand views. The <a href="../source/core/sigmoidal-contrast.c">sigmoidal-contrast.c</a> module reads an image, applies sigmoidal non-linearity contrast control, and writes the result to disk just like the previous contrast enhancement program, but now it does its work in parallel (assumes ImageMagick is built with OpenMP support).</p> 201 202<pre class="pre-scrollable">#include <stdio.h> 203#include <stdlib.h> 204#include <math.h> 205#include <magick/MagickCore.h> 206 207static MagickBooleanType SigmoidalContrast(ImageView *contrast_view, 208 const ssize_t y,const int id,void *context) 209{ 210#define QuantumScale ((MagickRealType) 1.0/(MagickRealType) QuantumRange) 211#define SigmoidalContrast(x) \ 212 (QuantumRange*(1.0/(1+exp(10.0*(0.5-QuantumScale*x)))-0.0066928509)*1.0092503) 213 214 RectangleInfo 215 extent; 216 217 register IndexPacket 218 *indexes; 219 220 register PixelPacket 221 *pixels; 222 223 register ssize_t 224 x; 225 226 extent=GetImageViewExtent(contrast_view); 227 pixels=GetImageViewAuthenticPixels(contrast_view); 228 for (x=0; x < (ssize_t) (extent.width-extent.x); x++) 229 { 230 SetPixelRed(pixels,RoundToQuantum(SigmoidalContrast(GetPixelRed(pixels))); 231 SetPixelGreen(pixels,RoundToQuantum(SigmoidalContrast(GetPixelGreen(pixels))); 232 SetPixelBlue(pixels,RoundToQuantum(SigmoidalContrast(GetPixelBlue(pixels))); 233 SetPixelOpacity(pixels,RoundToQuantum(SigmoidalContrast(GetPixelOpacity(pixels))); 234 pixels++; 235 } 236 indexes=GetImageViewAuthenticIndexes(contrast_view); 237 if (indexes != (IndexPacket *) NULL) 238 for (x=0; x < (ssize_t) (extent.width-extent.x); x++) 239 SetPixelIndex(indexes+x,RoundToQuantum(SigmoidalContrast(GetPixelIndex(indexes+x)))); 240 return(MagickTrue); 241} 242 243int main(int argc,char **argv) 244{ 245#define ThrowImageException(image) \ 246{ \ 247 \ 248 CatchException(exception); \ 249 if (contrast_image != (Image *) NULL) \ 250 contrast_image=DestroyImage(contrast_image); \ 251 exit(-1); \ 252} 253#define ThrowViewException(view) \ 254{ \ 255 char \ 256 *description; \ 257 \ 258 ExceptionType \ 259 severity; \ 260 \ 261 description=GetImageViewException(view,&severity); \ 262 (void) fprintf(stderr,"%s %s %lu %s\n",GetMagickModule(),description); \ 263 description=DestroyString(description); \ 264 exit(-1); \ 265} 266 267 ExceptionInfo 268 *exception; 269 270 Image 271 *contrast_image; 272 273 ImageInfo 274 *image_info; 275 276 ImageView 277 *contrast_view; 278 279 MagickBooleanType 280 status; 281 282 if (argc != 3) 283 { 284 (void) fprintf(stdout,"Usage: %s image sigmoidal-image\n",argv[0]); 285 exit(0); 286 } 287 /* 288 Read an image. 289 */ 290 MagickCoreGenesis(*argv,MagickTrue); 291 image_info=AcquireImageInfo(); 292 (void) CopyMagickString(image_info->filename,argv[1],MaxTextExtent); 293 exception=AcquireExceptionInfo(); 294 contrast_image=ReadImage(image_info,exception); 295 if (contrast_image == (Image *) NULL) 296 ThrowImageException(contrast_image); 297 /* 298 Sigmoidal non-linearity contrast control. 299 */ 300 contrast_view=NewImageView(contrast_image); 301 if (contrast_view == (ImageView *) NULL) 302 ThrowImageException(contrast_image); 303 status=UpdateImageViewIterator(contrast_view,SigmoidalContrast,(void *) NULL); 304 if (status == MagickFalse) 305 ThrowImageException(contrast_image); 306 contrast_view=DestroyImageView(contrast_view); 307 /* 308 Write the image then destroy it. 309 */ 310 status=WriteImages(image_info,contrast_image,argv[2],exception); 311 if (status == MagickFalse) 312 ThrowImageException(contrast_image); 313 contrast_image=DestroyImage(contrast_image); 314 exception=DestroyExceptionInfo(exception); 315 image_info=DestroyImageInfo(image_info); 316 MagickCoreTerminus(); 317 return(0); 318}</pre> 319</div> 320 <footer class="magick-footer"> 321 <p><a href="support.html">Donate</a> • 322 <a href="sitemap.html">Sitemap</a> • 323 <a href="links.html">Related</a> • 324 <a href="architecture.html">Architecture</a> 325</p> 326 <p><a href="magick-core.html#">Back to top</a> • 327 <a href="http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x89AB63D48277377A">Public Key</a> • 328 <a href="http://www.imagemagick.org/script/contact.php">Contact Us</a></p> 329 <p><small>© 1999-2016 ImageMagick Studio LLC</small></p> 330 </footer> 331</div><!-- /.container --> 332 333 <script src="https://localhost/ajax/libs/jquery/1.11.3/jquery.min.js"></script> 334 <script src="../js/magick.html"></script> 335</div> 336</body> 337</html> 338
