(PECL gmagick >= Unknown)
Gmagick::cropimage — Extracts a region of the image
Extracts a region of the image.
width
The width of the crop
height
The height of the crop
x
The X coordinate of the cropped region's top left corner
y
The Y coordinate of the cropped region's top left corner
The cropped Gmagick object
错误时抛出 GmagickException。