PHP | imagegammacorrect() function

The imagegammacorrect() function is an inbuilt function in PHP which is used to apply gamma correction to the given image given an input and an output gamma.

Syntax:

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

Parameters:This function accepts three parameters as mentioned above and described below:

• $image: It specifies the image to be worked upon.
• $inputgamma: It specifies the input gamma.
• $outputgamma: It specifies the output gamma.

Return Value: This function returns TRUE on success or FALSE on failure.

Exceptions: This function throws Exception on error.

Below given programs illustrate the imagegammacorrect() function in PHP:
Program 1:

<?php
// Create an image
$im = imagecreatefrompng('https://media.geeksforgeeks.org/wp-content/uploads/geeksforgeeks-13.png');

// Change the image gamma
imagegammacorrect($im, 3, 1.3);

// Output to browser
header('Content-Type: image/png');
imagepng($im);
imagedestroy($im);
?>

Output:

Program 2:

<?php
// Create an empty image
$im = imagecreatetruecolor(800, 250);

// Set the background to be light blue
imagefilledrectangle($im, 0, 0, 800, 250, imagecolorallocate($im, 0, 0, 180));

// Add text using a font from local
imagefttext($im, 80, 0, 50, 130, imagecolorallocate($im, 0, 150, 0), './Pacifico.ttf', 'GeeksforGeeks');

// Change the image gamma
imagegammacorrect($im, 3, 1.3);

// Output to browser
header('Content-Type: image/png');
imagepng($im);
imagedestroy($im);
?>

Output:

Reference: https://www.php.net/manual/en/function.imagegammacorrect.php