Imagick::thresholdImage

(PECL imagick 2, PECL imagick 3)

Imagick::thresholdImage — Changes the value of individual pixels based on a threshold

说明

public Imagick::thresholdImage(float $threshold, int $channel = Imagick::CHANNEL_DEFAULT): bool

Changes the value of individual pixels based on the intensity of each pixel compared to threshold. The result is a high-contrast, two color image.

参数

threshold

channel

返回值

成功时返回 true。

示例

示例 #1 Imagick::thresholdImage()

<?php
function thresholdimage($imagePath, $threshold, $channel) {
$imagick = new \Imagick(realpath($imagePath));
$imagick->thresholdimage($threshold * \Imagick::getQuantum(), $channel);
header("Content-Type: image/jpg");
echo $imagick->getImageBlob();
}

?>

发现了问题？

了解如何改进此页面 • 提交拉取请求 • 报告一个错误
＋添加备注

用户贡献的备注 1 note

up
1
php t traction dot de
12 years ago
getQuantumRange() can be handy here:

<?php
$i = new Imagick($imageFile);
$max = $i->getQuantumRange();
$max = $max["quantumRangeLong"];
$i->thresholdImage(0.77 * $max);
?>
＋添加备注

备份地址：http://www.lvesu.com/blog/php/imagick.thresholdimage.php