DOCUMENT SCANNER HAVING REPLACEABLE BACKING AND AUTOMATIC SELECTION OF REGISTRATION PARAMETERS

A system and method for determining the registration parameters necessary for registration or edge detection processing to enable the flexibility of changing the color of backing to suit a given application. The method includes scanning the backing surface to obtain at least two sets of gray level values; (b) determining an average gray level for each of the two color channels; (c) selecting a registration channel based on the average gray level; (d) determining a gray level deviation for the registration channel; and (e) determining registration parameters based on the average gray level and the gray level deviation of the registration channel.