PHP | imagegammacorrect() function

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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.zambiatek.com/wp-content/uploads/zambiatek-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', 'zambiatek'); 
  
// Change the image gamma 
imagegammacorrect($im, 3, 1.3); 
  
// Output to browser 
header('Content-Type: image/png'); 
imagepng($im); 
imagedestroy($im); 
?> 