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<Imagick::setImageBackgroundColorImagick::setImageBiasQuantum>
^ImagickLast updated: Mon, 26 Oct 2026

Imagick::setImageBias

(PECL imagick 2, PECL imagick 3)

Imagick::setImageBias — Sets the image bias for any method that convolves an image

Warning

This function has been DEPRECATED as of Imagick 3.4.4. Relying on this function is highly discouraged.

Description

public function Imagick::setImageBias(float $bias): bool

Sets the image bias for any method that convolves an image (e.g. Imagick::ConvolveImage()).

Parameters

bias

Return Values

Returns true on success.

Errors/Exceptions

Throws ImagickException on error.

Examples

Example #1 Imagick::setImageBias()

<?php
//requires ImageMagick version 6.9.0-1 to have an effect on convolveImage
function setImageBias($bias) {
    $imagick = new \Imagick(realpath("images/stack.jpg"));

    $xKernel = array(
        -0.70, 0, 0.70,
        -0.70, 0, 0.70,
        -0.70, 0, 0.70
    );

    $imagick->setImageBias($bias * \Imagick::getQuantum());
    $imagick->convolveImage($xKernel, \Imagick::CHANNEL_ALL);

    $imagick->setImageFormat('png');
    
    header('Content-type: image/png');
    echo $imagick->getImageBlob();
}

?>


<Imagick::setImageBackgroundColorImagick::setImageBiasQuantum>
^ImagickLast updated: Mon, 26 Oct 2026