ImageMagick has a number of functions that allow you to read, manipulate, write, or display an image. These functions are accessible through the various tools or the object-oriented Perl interface, PerlMagick. However, you can also access the functions directly from your program through the Magick Application Programmer Interface. To invoke the functions, write your program in your favorite language while making calls to the Magick image functions and link with libMagick.a, libMagick.so, or Magick.dll depending on your system.

The API is divided into a number of categories:

* ImageMagick Methods to Constitute an Image
* ImageMagick Image Methods
* Methods to Count the Colors in an Image
* Methods to Reduce the Number of Unique Colors in an Image
* Methods to Segment an Image with Thresholding Fuzzy c-Means
* Methods to Resize an Image
* Methods to Transform an Image
* Methods to Shear or Rotate an Image by an Arbitrary Angle
* Methods to Enhance an Image
* ImageMagick Image Effects Methods
* ImageMagick Image Decoration Methods
* Image Text Attributes Methods
* Methods to Annotate an Image
* Methods to Draw on an Image
* ImageMagick Methods to Create Image Thumbnails
* Methods to Interactively Display and Edit an Image
* Methods to Interactively Animate an Image Sequence
* Methods to Get or Set Image Pixels
* ImageMagick Cache Views Methods
* Image Pixel FIFO
* Methods to Read or Write Binary Large OBjects
* Methods to Read or List ImageMagick Image formats
* Methods to Compute a Message Digest for an Image
* ImageMagick Registry Methods
* ImageMagick Error Methods
* ImageMagick Memory Allocation Methods
* ImageMagick Progress Monitor Methods

Here is a sample program to get you started. To find out about all the functions that are available, read the source code. Each function is delineated with a full rows of percent signs with comments describing the parameters required for the function and what it does. For ease in finding a function, they are sorted in alphabetical order. Most of the image functions are found in image.c and effects.c.

Here is a full example of a program, demo.c, that reads a JPEG image, creates a thumbnail, and writes it to disk in the PNG image format. 

    #include <stdio.h>
    #include <string.h>
    #include <time.h>
    #include <sys/types.h>
    #include <magick/api.h>

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

      Image
        *image,
        *resize_image;

      ImageInfo
        *image_info;

      /*
        Initialize the image info structure and read an image.
      */
      InitializeMagick(*argv);
      GetExceptionInfo(&exception);
      image_info=CloneImageInfo((ImageInfo *) NULL);
      (void) strcpy(image_info->filename,"image.jpg");
      image=ReadImage(image_info,&exception);
      if (image == (Image *) NULL)
        MagickError(exception.severity,exception.reason,exception.description);
      /*
        Turn the image into a thumbnail.
      */
      resize_image=ResizeImage(image,106,80,MitchellFilter,1.0,&exception);
      if (resize_image == (Image *) NULL)
        MagickError(exception.severity,exception.reason,exception.description);
      DestroyImage(image);
      image=resize_image;
      /*
        Write the image as PNG and destroy it.
      */
      (void) strcpy(image->filename,"image.png");
      WriteImage(image_info,image);
      DestroyImageInfo(image_info);
      DestroyImage(image);
      DestroyMagick();
      return(0);
    }
Now we need to compile. On Unix, the command would look something like this: 
    setenv LD_LIBRARY_PATH /usr/local/lib
    gcc `Magick-config --cflags --cppflags` demo.c `Magick-config --ldflags --libs`
Another example is smile.c. Compile and excute it to display a smiley face on your X server.

For C++, use: 

    g++ `Magick++-config --cxxflags --cppflags` demo.cpp `Magick++-config --ldflags --libs`

Home Page   Image manipulation software that works like magic.