Imagick::separateImageChannel()
(PECL imagick 2.0.0)
Separates 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); ?>