    def crop_command
      target = @attachment.instance

      if target.cropping?(@attachment.name)
        w = target.send :"#{@attachment.name}_crop_w"
        h = target.send :"#{@attachment.name}_crop_h"
        x = target.send :"#{@attachment.name}_crop_x"
        y = target.send :"#{@attachment.name}_crop_y"
        ["-crop", "#{w}x#{h}+#{x}+#{y}"]
      end
    end