PHP | Imagick getImageChannelRange() Function

The Imagick::getImageChannelRange() function is an inbuilt function in PHP which is used to gets the range of channel.

Syntax:

array Imagick ::getImageChannelRange( $channel )

Parameters: This function accept single parameter $channel which specifies the channel to find image channel range. The default value of channel is Imagick::CHANNEL_DEFAULT.

Return Value: This function returns an array containing the minima and maxima of the required channel.

Below programs illustrate the Imagick ::getImageChannelRange() function in PHP:

Program 1:
Original Image:

<?php

// Create new Imagick object
$im = new Imagick(
'https://media.geeksforgeeks.org/wp-content/uploads/geeksforgeeks-15.png');

// Using getImageChannelRange function
// with red channel
$res = $im->getImageChannelRange(imagick::CHANNEL_RED);

// Display result
print_r($res);
?>

Output:

Array ( [minima] => 0 [maxima] => 65535 ) 

Program 2:
Original Image:

<?php

$string = "Computer Science portal for Geeks!";

// Creating new image of above String
// and add color
$im = new Imagick();
$draw = new ImagickDraw();

// Fill the color in image
$draw->setFillColor(new ImagickPixel('green'));

// Set the text font size
$draw->setFontSize(50);

$metrix = $im->queryFontMetrics($draw, $string);
$draw->annotation(0, 40, $string);
$im->newImage($metrix['textWidth'], $metrix['textHeight'],
        new ImagickPixel('white'));
// Draw the image
$im->drawImage($draw);
$im->setImageFormat('jpeg');

// Using getImageChannelRange function
// with red channel
$res = $im->getImageChannelRange(imagick::CHANNEL_GREEN);

// Display result
print_r($res);
?>

Output:

Array ( [minima] => 32896 [maxima] => 65535 ) 

Reference: http://php.net/manual/en/imagick.getimagechannelrange.php