PHP | Gmagick normalizeimage() Function

The Gmagick::normalizeimage() function is an inbuilt function in PHP which is used to enhances the contrast of a color image by adjusting the color of the pixel to span the entire range of colors.

Syntax:

Gmagick Gmagick::normalizeimage( $channel )

Parameters: This function accepts a single parameter $channel. This parameter provides the channel constant that is valid for channel mode. More than one channel can be combined using the bitwise operator. The defaults channel in Gmagick function is Gmagick:: CHANNEL_DEFAULT.

Return Value: This function returns Gmagick object on success.

Errors/Exceptions: This function throws GmagickException on error.

Below programs illustrates the Gmagick::normalizeimage() function in PHP:

Program 1:
Input Image:

<?php

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

// Normalize the image.
$gmagick->normalizeimage(Gmagick::CHANNEL_YELLOW);

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);


// Normalize the image.
$gmagick->normalizeimage(Gmagick::CHANNEL_ALL);

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

Output:

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