(PECL imagick 2, PECL imagick 3)
Imagick::setImageBias — Sets the image bias for any method that convolves an image
此函数在 Imagick 3.4.4 中被 废弃,强烈建议不要应用此函数。
Sets the image bias for any method that convolves an image (e.g. Imagick::ConvolveImage()).
bias
   成功时返回 true。
  
错误时抛出 ImagickException。
示例 #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();
}
?>