PHP Manual: Applies a function on the image

Description

public bool Imagick::functionImage(int $function, array $arguments, int $channel = Imagick::CHANNEL_DEFAULT)

Applies an arithmetic, relational, or logical expression to a pseudo image.

This method is available if Imagick has been compiled against ImageMagick version 6.4.9 or newer.

Parameters

function: Refer to this list of function constants
arguments: Array of arguments to pass to this function.

Return Values

Returns true on success.

Errors/Exceptions

Throws ImagickException on error.

Examples

Example #1 Create a sinusoidal gradient

<?php
$imagick = new Imagick();
$imagick->newPseudoImage(200, 200, 'gradient:black-white');
$arguments = array(3, -90);
$imagick->functionImage(Imagick::FUNCTION_SINUSOID, $arguments);

header("Content-Type: image/png");
$imagick->setImageFormat("png");
echo $imagick->getImageBlob();
?>

The above example will output something similar to:

Example #2 Create a gradient from the polynomial (4x^2 - 4x + 1)

<?php
$imagick = new Imagick();
$imagick->newPseudoImage(200, 200, 'gradient:black-white');
$arguments = array(4, -4, 1);
$imagick->functionImage(Imagick::FUNCTION_POLYNOMIAL, $arguments);

header("Content-Type: image/png");
$imagick->setimageformat("png");
echo $imagick->getImageBlob();
?>

The above example will output something similar to:

Example #3 Create a complex gradient from the polynomial (4x^2 - 4x^2 + 1) modulated by a sinusoidal gradient

<?php
$imagick1 = new Imagick();
$imagick1->newPseudoImage(200, 200, 'gradient:black-white');
$arguments = array(9, -90);
$imagick1->functionImage(Imagick::FUNCTION_SINUSOID, $arguments);

$imagick2 = new Imagick();
$imagick2->newPseudoImage(200, 200, 'gradient:black-white');
$arguments = array(0.5, 0);
$imagick2->functionImage(Imagick::FUNCTION_SINUSOID, $arguments);
$imagick1->compositeimage($imagick2, Imagick::COMPOSITE_MULTIPLY, 0, 0);

header("Content-Type: image/png");
$imagick1->setImageFormat("png");
echo $imagick1->getImageBlob();
?>

The above example will output something similar to: