文字
Imagick::thresholdImage
(PECL imagick 2.0.0)
Imagick::thresholdImage — Changes the value of individual pixels based on a threshold
说明
bool Imagick::thresholdImage
( float
$threshold
[, int $channel = Imagick::CHANNEL_ALL
] )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 。
范例
Example #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 ();
}
?> 用户评论:
[#1] php t traction dot de [2012-06-29 07:25:11]
getQuantumRange() can be handy here:
<?php
$i = new Imagick($imageFile);
$max = $i->getQuantumRange();
$max = $max["quantumRangeLong"];
$i->thresholdImage(0.77 * $max);
?>