An apparatus and methods for processing video data are described. A P gain, I gain and D gain for use in maintaining the heading of the watercraft is determined and used to calculate factors related to heading error, cumulative heading error and rate of change of heading error. The pedal arm assembly is injection molded such that the arm and the pedal member are integrally molded as a single member that is generally resistant to corrosion. In one embodiment, the sensed data windows corresponding to image windows such as would be provided by a visual surveillance system. The article is characterized by essentially constant optical characteristics over a wide temperature range. The seat defines an aperture having a sealing surface disposed about a central axis.