The MagickWand API is the recommended interface between the C programming language and the ImageMagick image processing libraries. Unlike the MagickCore C API, MagickWand uses only a few opaque types. Accessors are available to set or get important wand properties. A description of the MagickWand public methods are found here: Magick Wand Methods Set or Get Magick Wand Properties Magick Wand Image Methods Pixel Iterator Methods Pixel Wand Methods Image Vector Drawing Deprecated Methods After you write your MagickWand program, compile it like this:
      cc `Wand-config --cflags --cppflags` wand.c `Wand-config --ldflags --libs`
Here is a example program that utilizes the MagickWand API to get you started, wand.c. It reads an image, creates a thumbnail, and writes the result to disk.
    #include <stdio.h>
    #include <stdlib.h>
    #include <wand/MagickWand.h>

    int main(int argc,char **argv)
    {
    #define ThrowWandException(wand) \
    { \
      char \
        *description; \
     \
      ExceptionType \
        severity; \
     \
      description=MagickGetException(wand,&severity); \
      (void) fprintf(stderr,"%s %s %lu %s\n",GetMagickModule(),description); \
      description=(char *) MagickRelinquishMemory(description); \
      exit(-1); \
    }

      MagickBooleanType
        status;

      MagickWand
        *magick_wand;

      if (argc != 3)
        {
          (void) fprintf(stdout,"Usage: %s image thumbnail\n",argv[0]);
          exit(0);
        }
      /*
        Read an image.
      */
      MagickWandGenesis();
      magick_wand=NewMagickWand();
      status=MagickReadImage(magick_wand,argv[1]);
      if (status == MagickFalse)
        ThrowWandException(magick_wand);
      /*
        Turn the images into a thumbnail sequence.
      */
      MagickResetIterator(magick_wand);
      while (MagickNextImage(magick_wand) != MagickFalse)
        MagickResizeImage(magick_wand,106,80,LanczosFilter,1.0);
      /*
        Write the image then destroy it.
      */
      status=MagickWriteImages(magick_wand,argv[2],MagickTrue);
      if (status == MagickFalse)
        ThrowWandException(magick_wand);
      magick_wand=DestroyMagickWand(magick_wand);
      MagickWandTerminus();
      return(0);
    }
Here is another program that shows one way to get and set image pixels with the MagickWand API, contrast.c. It reads an image, applies sigmoidal non-linearity contrast control, and writes the result to disk.
    #include <stdio.h>
    #include <stdlib.h>
    #include <math.h>
    #include <wand/MagickWand.h>

    int main(int argc,char **argv)
    {
    #define QuantumScale  ((MagickRealType) 1.0/(MagickRealType) QuantumRange)
    #define SigmoidalContrast(x) \
      (QuantumRange*(1.0/(1+exp(10.0*(0.5-QuantumScale*x)))-0.0066928509)*1.0092503)
    #define ThrowWandException(wand) \
    { \
      char \
        *description; \
     \
      ExceptionType \
        severity; \
     \
      description=MagickGetException(wand,&severity); \
      (void) fprintf(stderr,"%s %s %lu %s\n",GetMagickModule(),description); \
      description=(char *) MagickRelinquishMemory(description); \
      exit(-1); \
    }

      long
        y;

      MagickBooleanType
        status;

      MagickPixelPacket
        pixel;

      MagickWand
        *contrast_wand,
        *image_wand;

      PixelIterator
        *contrast_iterator,
        *iterator;

      PixelWand
        **contrast_pixels,
        **pixels;

      register long
        x;

      unsigned long
        width;

      if (argc != 3)
        {
          (void) fprintf(stdout,"Usage: %s image sigmoidal-image\n",argv[0]);
          exit(0);
        }
      /*
        Read an image.
      */
      MagickWandGenesis();
      image_wand=NewMagickWand();
      status=MagickReadImage(image_wand,argv[1]);
      if (status == MagickFalse)
        ThrowWandException(image_wand);
      contrast_wand=CloneMagickWand(image_wand);
      /*
        Sigmoidal non-linearity contrast control.
      */
      iterator=NewPixelIterator(image_wand);
      contrast_iterator=NewPixelIterator(contrast_wand);
      if ((iterator == (PixelIterator *) NULL) ||
          (contrast_iterator == (PixelIterator *) NULL))
        ThrowWandException(image_wand);
      for (y=0; y < (long) MagickGetImageHeight(image_wand); y++)
      {
        pixels=PixelGetNextIteratorRow(iterator,&width);
        contrast_pixels=PixelGetNextIteratorRow(contrast_iterator,&width);
        if ((pixels == (PixelWand **) NULL) ||
            (contrast_pixels == (PixelWand **) NULL))
          break;
        for (x=0; x < (long) width; x++)
        {
          PixelGetMagickColor(pixels[x],&pixel);
          pixel.red=SigmoidalContrast(pixel.red);
          pixel.green=SigmoidalContrast(pixel.green);
          pixel.blue=SigmoidalContrast(pixel.blue);
          pixel.index=SigmoidalContrast(pixel.index);
          PixelSetMagickColor(contrast_pixels[x],&pixel);
        }
        (void) PixelSyncIterator(contrast_iterator);
      }
      if (y < (long) MagickGetImageHeight(image_wand))
        ThrowWandException(image_wand);
      contrast_iterator=DestroyPixelIterator(contrast_iterator);
      iterator=DestroyPixelIterator(iterator);
      image_wand=DestroyMagickWand(image_wand);
      /*
        Write the image then destroy it.
      */
      status=MagickWriteImages(contrast_wand,argv[2],MagickTrue);
      if (status == MagickFalse)
        ThrowWandException(image_wand);
      contrast_wand=DestroyMagickWand(contrast_wand);
      MagickWandTerminus();
      return(0);
    }

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