US Patent 7386172 Image recognition method

In a pattern recognition section of a digital color copying machine, a position analysis section successively selects, in units of a predetermined number, position data of rectangular regions stored in a position information memory, calculates distances between the rectangular regions, and determines whether a combination of the distances coincides with that of a pattern to be detected. If the combination of distances coincides with that of the pattern to be detected, the position analysis section outputs to a rear-stage page memory a control signal for resetting the page memory.