The MagickCore API is a low-level interface between the C programming language and the ImageMagick image processing libraries and is recommended for wizard-level programmers only. Unlike the MagickWand 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: Initialize or Destroy the ImageMagick Environment Constitute an Image Composite an Image Image Methods Count the Colors in an Image Dealing with Image Colorspaces Dealing with Image Layers Dealing with Image Profiles Reduce the Number of Unique Colors in an Image Segment an Image with Thresholding Fuzzy c-Means Resize an Image Transform an Image Shear or Rotate an Image by an Arbitrary Angle Enhance an Image Add an Effect Add a Special Effect Decorate an Image Get/Set Image Properties Annotate an Image Paint on an Image Draw on an Image Create an Image Thumbnail Compare an Image to a Reconstructed Image Interactively Display and Edit an Image Interactively Animate an Image Sequence Get or Set Image Pixels Working with Image Lists Working with Cache Views The Pixel FIFO Read or Write Binary Large OBjects Loadable Modules Compute a Message Digest for an Image The Image Registry Dealing with Exceptions Memory Allocation Monitor or Limit Resource Consumption Monitor the Progress of an Image Operation Get the Version and Copyrights Deprecated Methods After you write your MagickCore program, compile it like this:
      cc `Magick-config --cflags --cppflags` core.c `Magick-config --ldflags --libs`
Here is a example program that utilizes the MagickCore API to get you started, core.c. It reads a GIF image, creates a thumbnail, and writes it to disk in the PNG image format.
      #include <stdio.h>
      #include <stdlib.h>
      #include <string.h>
      #include <time.h>
      #include <magick/MagickCore.h>

      int main(int argc,char **argv)
      {
        ExceptionInfo
          *exception;

        Image
          *image,
          *images,
          *resize_image,
          *thumbnails;

        ImageInfo
          *image_info;

        if (argc != 3)
          {
            (void) fprintf(stdout,"Usage: %s image thumbnail\n",argv[0]);
            exit(0);
          }
        /*
          Initialize the image info structure and read an image.
        */
        MagickCoreGenesis(*argv,MagickTrue);
        exception=AcquireExceptionInfo();
        image_info=CloneImageInfo((ImageInfo *) NULL);
        (void) strcpy(image_info->filename,argv[1]);
        images=ReadImage(image_info,exception);
        if (exception->severity != UndefinedException)
          CatchException(exception);
        if (images == (Image *) NULL)
          exit(1);
        /*
          Convert the image to a thumbnail.
        */
        thumbnails=NewImageList();
        while ((image=RemoveFirstImageFromList(&images)) != (Image *) NULL)
        {
          resize_image=ResizeImage(image,106,80,LanczosFilter,1.0,exception);
          if (resize_image == (Image *) NULL)
            MagickError(exception->severity,exception->reason,exception->description);
          (void) AppendImageToList(&thumbnails,resize_image);
          DestroyImage(image);
        }
        /*
          Write the image thumbnail.
        */
        (void) strcpy(thumbnails->filename,argv[2]);
        WriteImage(image_info,thumbnails);
        /*
          Destroy the image thumbnail and exit.
        */
        thumbnails=DestroyImageList(thumbnails);
        image_info=DestroyImageInfo(image_info);
        exception=DestroyExceptionInfo(exception);
        MagickCoreTerminus();
        return(0);
      }

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