The Imagick::levelImage() function is an inbuilt function in PHP that is used to adjust the levels of an image.
Syntax:
bool Imagick::levelImage( $blackPoint, $gamma,
$whitePoint, $channel = Imagick::CHANNEL_DEFAULT )
Parameters: This function accepts four parameters as mentioned above and described below:
- blackPoint: This parameter holds the black point of an image.
- gamma: This parameter holds the value of gamma.
- whitePoint: This parameter holds the white point of an image.
- channel: This parameter holds the channel constant that is valid for channel mode. Use a bit-wise operator to combine more than one channel.
Return Value: This function returns TRUE on success.
Errors/Exceptions: This function throws ImagickException on error. The below program illustrates the Imagick::levelImage() function in PHP.
Program:
php
<?php// Store the image into variable$imagick="https://media.geeksforgeeks.org/wp-content/uploads/neveropen-9.png";// Declare new Imagick object$imagick = new \Imagick($imagick);// Use Imagick::newPseudoImage() function to create// a new image using ImageMagick pseudo-formats$imagick->newPseudoimage(700, 250, 'radial-gradient:red-blue');// Function to set image format$imagick->setFormat('png');// Use Imagick::getQuantum() function to// return the ImageMagick quantum range$quantum = $imagick->getQuantum();// Use Imagick::levelImage() function$imagick->levelImage($blackPoint / 100, $gamma, $quantum * $whitePoint / 100); header("Content-Type: image/png");// Display the image as outputecho $imagick->getImageBlob();?> |
Output:
Reference: https://www.php.net/manual/en/imagick.levelimage.php
