code: def crop(self, height, width, center_i=None, center_j=None):
          
          gray_im_crop = self.gray.crop(height, width, center_i, center_j)
          depth_im_crop = self.depth.crop(height, width, center_i, center_j)
          return GdImage.from_grayscale_and_depth(gray_im_crop, depth_im_crop)
docs: Crop the image centered around center_i, center_j.
  
          Parameters
          ----------
          height : int
              The height of the desired image.
  
          width : int
              The width of the desired image.
  
          center_i : int
              The center height point at which to crop. If not specified, the center
              of the image is used.
  
          center_j : int
              The center width point at which to crop. If not specified, the center
              of the image is used.
  
          Returns
          -------
          :obj:`Image`
              A cropped Image of the same type.