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# Magick++ API for GraphicsMagick

# Introduction

Magick++ is the object-oriented C++ API to the GraphicsMagick image-processing library, the most comprehensive open-source image processing package available. Read the ChangeLog for Magick++.

Magick++ supports an object model which is inspired by PerlMagick. Images support implicit reference counting so that copy constructors and assignment incur almost no cost. The cost of actually copying an image (if necessary) is done just before modification and this copy is managed automatically by Magick++. De-referenced copies are automatically deleted. The image objects support value (rather than pointer) semantics so it is trivial to support multiple generations of an image in memory at one time.

Magick++ provides integrated support for the Standard Template Library (STL) so that the powerful containers available (e.g. deque, vector, list, and map) can be used to write programs similar to those possible with PERL & PerlMagick. STL-compatible template versions of GraphicsMagick's list-style operations are provided so that operations may be performed on multiple images stored in STL containers.

# Documentation

Detailed documentation are provided for all Magick++ classes, class methods, and template functions which comprise the API.

# Obtaining Magick++

Magick++ is included as part of GraphicsMagick source releases and may be retrieved via ftp or CVS.

# Installation

Installation is very easy since Magick++ is part of GraphicsMagick and is built by default. Once GraphicsMagick is built, then Magick++ is available for use.

# Usage

A helper script named GraphicsMagick++-config is installed in the same directory as the GraphicsMagick gm program under Unix which assists with recalling compilation options required to compile and link programs which depend on Magick++. For example, the following command will compile and link the source file example.cpp to produce the executable example (notice that quotes are backward quotes):

    c++ -o example example.cpp `GraphicsMagick++-config --cppflags --cxxflags
      --ldflags --libs`

Windows users may get started by manually editing a project file for one of the Magick++ demo programs.

It is necessary to initialize the GraphicsMagick library prior to using the Magick++ library. This initialization is performed by passing the path to the GraphicsMagick DLLs (assumed to be in the same directory as your program) to the InitializeMagick() function call. This is commonly performed by providing the path to your program (argv[0]) as shown in the following example:

    int main( int /*argc*/, char ** argv)
    {
      InitializeMagick(*argv);

If you don't have the path to your executable, then pass NULL and usually the library will be found anyway. Besides helping to find the GraphicsMagick DLL/library and configuration files, InitializeMagick() initializes all of the semaphores and data necessary for a multi-threaded program to be completely thread safe. This step used to be optional, but it is now absolutely required. Failure to initialize GraphicsMagick will result in an application crash.

# Reporting Bugs

Please report any bugs via the GraphicsMagick Bug Tracker. Questions regarding usage should be directed to Bob Friesenhahn.

Copyright © Bob Friesenhahn 1999 - 2012