Strategies are set forth herein for quantizing and dithering original image information to produce quantized image information. The second gear is arranged in tandem with the first gear. A transmission cable has a first end connectable with the output of the processing circuit to receive the exercising data and a second end engageable with a counterpart device of the external device for forwarding the exercising data to the external device. The added brick texture increases the surface area of the brick to improve the bonding of the brick surface coating and to provide mechanical underpinning for the surface coating. With either embodiment controllers can be programmed to adjust positions of the control valves based upon feedback from pressure sensors.