Imagick::separateImageChannel

(PECL imagick 2.0.0)

Imagick::separateImageChannelSeparates a channel from the image

说明

Imagick::separateImageChannel ( int $channel ) : bool

Separates 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);

?>