Imagick::separateImageChannel
(PECL imagick 2.0.0)
Imagick::separateImageChannel — Separates a channel from the image
说明
Imagick::separateImageChannel
( int
$channel
) : boolSeparates a channel from the image and returns a grayscale image. A channel is a particular color component of each pixel in the image.
参数
-
channel
-
Which 'channel' to return. For colorspaces other than RGB, you can still use the CHANNEL_RED, CHANNEL_GREEN, CHANNEL_BLUE constants to indicate the 1st, 2nd and 3rd channels.
返回值
成功时返回 TRUE
。
错误/异常
错误时抛出 ImagickException。
范例
Example #1 Imagick::separateImageChannel()
<?php
function separateImageChannel($imagePath, $channel) {
$imagick = new \Imagick(realpath($imagePath));
$imagick->separateimagechannel($channel);
header("Content-Type: image/jpg");
echo $imagick->getImageBlob();
}
separateImageChannel($imagePath, \Imagick::CHANNEL_GREEN);
?>