ImageMagick was created in 1987 by John Cristy when working at DuPont, to convert 24-bit images to 8-bit images, so they could be displayed on most screens. It was freely released in 1990 when DuPont agreed to transfer copyright to ImageMagick Studio LLC, still currently the project maintainer organization. In May 2016, it was reported that ImageMagick had a vulnerability through which an attacker can execute arbitrary code on servers that use the application to edit user-uploaded images. Security experts including CloudFlare researchers observed actual use of the vulnerability in active hacking attempts. The security flaw was due to ImageMagick calling backend tools without first properly checking to ensure path and file names are free of improper shell commands. The vulnerability did not affect ImageMagick distributions that included a properly configured security policy.
Features and capabilities
The software mainly consists of a number of command-line interface utilities for manipulating images. ImageMagick does not have a robust graphical user interface to edit images as do Adobe Photoshop and GIMP, but does include – for Unix-like operating systems – a basic native X WindowGUI for rendering and manipulating images and API libraries for many programming languages. Execute the following on Linux or UNIX to launch the GUI: Otherwise, images may be edited directly by various command-line parameters without launching a GUI at all. The program uses magic numbers to identify image file formats. For a full list of supported formats, execute, on Linux or UNIX: A number of programs, such as Drupal, MediaWiki, phpBB, and vBulletin, can use ImageMagick to create image thumbnails if installed. ImageMagick is also used by other programs, such as LyX, for converting images. ImageMagick has a fully integrated Perlbinding called PerlMagick, as well as many others: G2F, MagickCore, MagickWand, ChMagick, ImageMagickObject, Magick++, JMagick, L-Magick, NMagick, MagickNet, PascalMagick, MagickWand for PHP, IMagick, PythonMagick, RMagick, or TclMagick.
One of the basic and thoroughly-implemented features of ImageMagick is its ability to efficiently and accurately convert images between different file formats.
Color quantization
The number of colors in an image can be reduced to an arbitrary number and this is done by weighing the most prominent color values present among the pixels of the image. A related capability is the posterization artistic effect, which also reduces the number of colors represented in an image. The difference between this and standard color quantization is that while in standard quantization the final palette is selected based upon a weighting of the prominence of existing colors in the image, posterization creates a palette of colors smoothly distributed across the spectrum represented in the image. Whereas with standard color quantization all of the final color values are ones that were in the original image, the color values in a posterized image may not have been present in the original image but are in between the original color values.
Dithering
A fine control is provided for the dithering that occurs during color and shading alterations, including the ability to generate halftone dithering.
High-dynamic-range images: accurately represent the wide range of intensity levels found in real scenes ranging from the brightest direct sunlight to the deepest darkest shadows.
Encipher or decipher an image: convert ordinary images into unintelligible gibberish and back again.
Virtual pixel support: convenient access to pixels outside the image region.
Large image support: read, process, or write mega-, giga-, or tera-pixel image sizes.
Heterogeneous distributed processing: certain algorithms are OpenCL-enabled to take advantage of speed-ups offered by executing in concert across heterogeneous platforms consisting of CPUs, GPUs, and other processors.
Distributed pixel cache: offload intermediate pixel storage to one or more remote servers.
ImageMagick on the iPhone: convert, edit, or compose images on your iOS computing device such as the iPhone or iPad.
is a fork of ImageMagick 5.5.2 made in 2002, emphasizing the cross-release stability of the programming API and command-line options. GraphicsMagick emerged as a result of irreconcilable differences in the developers' group.
