(PECL imagick 2, PECL imagick 3)
Imagick::separateImageChannel — Separates a channel from the image
Separates a channel from the image and returns a grayscale image. A channel is a particular color component of each pixel in the image.
channelWhich '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.
Returns true on success.
Throws ImagickException on error.
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);
?>