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