PHP | Gmagick gammaimage() Function

The Gmagick::gammaimage() function is an inbuilt function in PHP which is used to corrects the image by providing the Gamma-correction. The view of the same images is different on the different devices. In this way, the image intensities are represented on the screen.

Syntax:

Gmagick Gmagick::gammaimage( $gamma )

Parameters: This function accepts a single parameters $gamma which holds the value of gamma-correction.

Return Value: This function returns gamma corrected Gmagick object.

Errors/Exceptions: This function throws GmagickException on error.

Below programs illustrate the Gmagick::gammaimage() function in PHP:

Program 1:
Original Image:

<?php

// Create a Gmagick object
$gmagick = new Gmagick(
'https://media.geeksforgeeks.org/wp-content/uploads/tech.png');

// Use gammaimage() function
$gmagick->gammaimage(5);

header('Content-type: image/png');

// Output the image
echo $gmagick;
?>

Output:

Program 2:

<?php

// Create a GmagickDraw object
$draw = new GmagickDraw();

// Create GmagickPixel object
$strokeColor = new GmagickPixel('Red');
$fillColor = new GmagickPixel('Green');

// Set the color, opacity of image
$draw->setStrokeOpacity(1);
$draw->setStrokeColor('Red');
$draw->setFillColor('Green');

// Set the width and height of image
$draw->setStrokeWidth(7);
$draw->setFontSize(72);

// Function to draw circle
$draw->circle(250, 250, 100, 150);

$gmagick = new Gmagick();
$gmagick->newImage(500, 500, 'White');
$gmagick->setImageFormat("png");
$gmagick->drawImage($draw);

// Use gammaimage() function
$gmagick->gammaimage(10);

// Display the output image
header("Content-Type: image/png");
echo $gmagick->getImageBlob();
?>

Output:

Reference: http://php.net/manual/en/gmagick.gammaimage.php