PHP Manual: Apply a gamma correction to a GD image

Description

bool imagegammacorrect ( resource $image , float $inputgamma , float $outputgamma )

Applies gamma correction to the given gd image given an input and an output gamma.

Parameters

image: An image resource, returned by one of the image creation functions, such as imagecreatetruecolor.
inputgamma: The input gamma.
outputgamma: The output gamma.

Return Values

Returns TRUE on success or FALSE on failure.

Examples

Example #1 imagegammacorrect usage


<?php
// Create image instance
$im = imagecreatefromgif('php.gif');

// Correct gamma, out = 1.537
imagegammacorrect($im, 1.0, 1.537);

// Save and free image
imagegif($im, './php_gamma_corrected.gif');
imagedestroy($im);
?>