DUAL LEVEL PATTERN RECOGNITION SYSTEM

A pattern recognition system has both coarse and fine levels of analysis in which a coarse array representation of a workpiece pattern is formed and used to identify the workpiece pattern as either a referench character or as a member of an ambiguous set of reference characters which are represented by identical coarse array representations. At least portions of a fine array representation of a workpiece pattern which has been classified as a member of a set of reference characters are compared to corresponding portions of fine array representations of reference characters in the set identified by the classification. The pattern recognition system has a learning system through which reference characters may be introduced into the recognition system and through which a representation of a workpiece pattern which was not identified may be incorporated into an existing set of reference characters of the recognition system.