(PECL gmagick >= Unknown)
Gmagick::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.
channel
Identify which channel to extract: RedChannel, GreenChannel, BlueChannel, OpacityChannel, CyanChannel, MagentaChannel, YellowChannel, BlackChannel.
The Gmagick object on success
锟斤拷锟斤拷时锟阶筹拷 GmagickException锟斤拷