(PECL imagick 2.0.0)
Imagick::getPixelRegionIterator — Get an ImagickPixelIterator for an image section
Get an ImagickPixelIterator for an image section.
x
     The x-coordinate of the region.
y
     The y-coordinate of the region.
columns
     The width of the region.
rows
     The height of the region.
Returns an ImagickPixelIterator for an image section.
Throws ImagickException on error.