The GD Graphics Library is a graphics
software
Software is a set of computer programs and associated software documentation, documentation and data (computing), data. This is in contrast to Computer hardware, hardware, from which the system is built and which actually performs the work.
...
library by Thomas Boutell and others for dynamically manipulating
image
An image is a visual representation of something. It can be two-dimensional, three-dimensional, or somehow otherwise feed into the visual system to convey information. An image can be an artifact, such as a photograph or other two-dimensio ...
s. Its native
programming language
A programming language is a system of notation for writing computer programs. Most programming languages are text-based formal languages, but they may also be graphical. They are a kind of computer language.
The description of a programming l ...
is
ANSI
The American National Standards Institute (ANSI ) is a private non-profit organization that oversees the development of voluntary consensus standards for products, services, processes, systems, and personnel in the United States. The organ ...
C, but it has interfaces for many other programming languages. It can create
GIF
The Graphics Interchange Format (GIF; or , see pronunciation) is a bitmap image format that was developed by a team at the online services provider CompuServe led by American computer scientist Steve Wilhite and released on 15 June 1987. ...
s,
JPEG
JPEG ( ) is a commonly used method of lossy compression for digital images, particularly for those images produced by digital photography. The degree of compression can be adjusted, allowing a selectable tradeoff between storage size and im ...
s,
PNGs, and
WBMPs. Support for drawing GIFs was dropped in 1999 when
Unisys
Unisys Corporation is an American multinational information technology (IT) services and consulting company headquartered in Blue Bell, Pennsylvania. It provides digital workplace solutions, cloud, applications, and infrastructure solutions ...
revoked the royalty-free
license
A license (or licence) is an official permission or permit to do, use, or own something (as well as the document of that permission or permit).
A license is granted by a party (licensor) to another party (licensee) as an element of an agreeme ...
granted to non-commercial software projects for the
LZW compression method used by GIFs. When the Unisys
patent
A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an sufficiency of disclosure, enabling disclo ...
expired worldwide on July 7, 2004, GIF support was subsequently re-enabled.
GD originally stood for "GIF Draw". However, since the revoking of the Unisys license, it has informally stood for "Graphics Draw".
GD can create images composed of lines, arcs, text (using program-selected fonts), other images, and multiple colors. Version 2.0 adds support for
truecolor images,
alpha channel
In computer graphics, alpha compositing or alpha blending is the process of combining one image with a background to create the appearance of partial or full transparency. It is often useful to render picture elements (pixels) in separate pass ...
s,
resampling (for smooth resizing of truecolor images), and many other features.
GD supports numerous programming languages including
C,
PHP
PHP is a General-purpose programming language, general-purpose scripting language geared toward web development. It was originally created by Danish-Canadian programmer Rasmus Lerdorf in 1993 and released in 1995. The PHP reference implementati ...
,
Perl
Perl is a family of two High-level programming language, high-level, General-purpose programming language, general-purpose, Interpreter (computing), interpreted, dynamic programming languages. "Perl" refers to Perl 5, but from 2000 to 2019 it ...
,
Python,
OCaml
OCaml ( , formerly Objective Caml) is a general-purpose, multi-paradigm programming language which extends the Caml dialect of ML with object-oriented features. OCaml was created in 1996 by Xavier Leroy, Jérôme Vouillon, Damien Doligez, D ...
,
Tcl,
Lua
Lua or LUA may refer to:
Science and technology
* Lua (programming language)
* Latvia University of Agriculture
* Last universal ancestor, in evolution
Ethnicity and language
* Lua people, of Laos
* Lawa people, of Thailand sometimes referred t ...
,
Pascal,
GNU Octave
GNU Octave is a high-level programming language primarily intended for scientific computing and numerical computation. Octave helps in solving linear and nonlinear problems numerically, and for performing other numerical experiments using a lang ...
,
REXX
Rexx (Restructured Extended Executor) is a programming language that can be interpreted or compiled. It was developed at IBM by Mike Cowlishaw. It is a structured, high-level programming language designed for ease of learning and reading. ...
,
Ruby
A ruby is a pinkish red to blood-red colored gemstone, a variety of the mineral corundum (aluminium oxide). Ruby is one of the most popular traditional jewelry gems and is very durable. Other varieties of gem-quality corundum are called sapp ...
and
Go. In addition, the "Fly" command line interpreter allows for image creation ("on the fly") using GD. GD scripts can thus be written in potentially any language and run using this tool.
GD is extensively used with PHP, where a modified version supporting additional features is included by default as of PHP 4.3 and was an option before that. As of PHP 5.3, a system version of GD may be used as well, to get the additional features that were previously available only to the bundled version of GD.
Example
The following is an example which outputs a 3D looking pie chart (from the PHP GD documentation on th
imagefilledarc()function).
50; $i--)
imagefilledarc($image, 50, 50, 100, 50, 0, 45, $navy, IMG_ARC_PIE);
imagefilledarc($image, 50, 50, 100, 50, 45, 75, $gray, IMG_ARC_PIE);
imagefilledarc($image, 50, 50, 100, 50, 75, 360, $red, IMG_ARC_PIE);
// Flush the image
header('Content-type: image/png');
imagepng($image);
imagedestroy($image);
?>
See also
*
GDAL
The Geospatial Data Abstraction Library (GDAL) is a computer software library for reading and writing raster and vector geospatial data formats (e.g. shapefile), and is released under the permissive X/MIT style free software license by the O ...
- for geospatial images
*
GraphicsMagick
*
ImageMagick
ImageMagick, invoked from the command line as magick, is a free and open-source cross-platform software suite for displaying, creating, converting, modifying, and editing raster images. Created in 1987 by John Cristy, it can read and write ove ...
*
Netpbm
Netpbm (formerly Pbmplus) is an open-source package of graphics programs and a programming library. It is used mainly in the Unix world, where one can find it included in all major open-source operating system distributions, but also works on Mic ...
*
Python Imaging Library
References
External links
GD Graphics Library
archived
Image Functions (PHP) support in
PHP
PHP is a General-purpose programming language, general-purpose scripting language geared toward web development. It was originally created by Danish-Canadian programmer Rasmus Lerdorf in 1993 and released in 1995. The PHP reference implementati ...
{{DEFAULTSORT:Gd Graphics Library
Free software programmed in C
Graphics libraries
Software using the BSD license