Installing/Configuring
PHP Manual

Installation

To enable GD-support configure PHP --with-gd[=DIR], where DIR is the GD base install directory. To use the recommended bundled version of the GD library (which was first bundled in PHP 4.3.0), use the configure option --with-gd. GD library requires libpng and libjpeg to compile.

In Windows, you'll include the GD2 DLL php_gd2.dll as an extension in php.ini. The GD1 DLL php_gd.dll was removed in PHP 4.3.2. Also note that the preferred truecolor image functions, such as imagecreatetruecolor(), require GD2.

Enhance the capabilities of GD to handle more image formats by specifying the --with-XXXX configure switch to your PHP configure line.

Supported image formats
Image Format Configure Switch
jpeg To enable support for jpeg add --with-jpeg-dir=DIR. Jpeg 6b, 7 or 8 are supported.
png To enable support for png add --with-png-dir=DIR. Note, libpng requires the zlib library, therefore add --with-zlib-dir[=DIR] to your configure line.
xpm To enable support for xpm add --with-xpm-dir=DIR. If configure is not able to find the required libraries, you may add the path to your X11 libraries.

Note: When compiling PHP with libpng, you must use the same version that was linked with the GD library.

Enhance the capabilities of GD to deal with different fonts by specifying the --with-XXXX configure switch to your PHP configure line.

Supported font libraries
Font library Configure Switch
FreeType 1.x To enable support for FreeType 1.x add --with-ttf[=DIR].
FreeType 2 To enable support for FreeType 2 add --with-freetype-dir=DIR.
T1lib To enable support for T1lib (Postscript Type 1 fonts) add --with-t1lib[=DIR].
Native TrueType string function To enable support for native TrueType string function add --enable-gd-native-ttf.


Installing/Configuring
PHP Manual