# File lib/dragonfly/processing/image_magick_processor.rb, line 29
      def crop(temp_object, opts={})
        width   = opts[:width]
        height  = opts[:height]
        gravity = GRAVITIES[opts[:gravity]]
        x       = "#{opts[:x] || 0}"
        x = '+' + x unless x[/^[+-]/]
        y       = "#{opts[:y] || 0}"
        y = '+' + y unless y[/^[+-]/]
      
        convert(temp_object, "-crop #{width}x#{height}#{x}#{y}#{" -gravity #{gravity}" if gravity}")
      end