Imagick::separateImageChannel

(PECL imagick 2.0.0)

Imagick::separateImageChannel — Separates a channel from the image

说明

bool Imagick::separateImageChannel ( int $channel )

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 );

 ?>