Patent Document ID: 4015240
Application ID: 05549399
Patent Status: 1

Claim One:
1. Pattern recognition apparatus enabling the determination of the coordinates and angular positions of characteristic points such as fingerprint minutiae, comprising; a. sensing means developing a plurality of signals in response to a presented pattern containing characteristic points which are to be identified, b. conversion means responsive to said signals for converting said pattern into a binary encoded image containing many levels of gray scale data, c. temporary storage means for temporarily storing in a predetermined sequence portions of said data, which portions comprise sets of points corresponding to said binary encoded image, each point of which having a value indicative of the gray scale level thereof, d. means for comparing and averaging said data in said storage means for converting said data into a second binary encoded image comprised of sets of points, each containing one of two levels of gray scale data and which image has been corrected for imperfections in said presented pattern, said means comprise a plurality of logic circuits all of which simultaneously compare and average portions of said data, e. continuity means for detecting only those points of said second binary encoded image that are contiguous to a predetermined set of coordinates in said presented pattern, said means comprise a plurality of continuity logic circuits all of which simultaneously detect contiguous points located in portions of said second binary encoded image whereby the detection of all points therein is simultaneous, f. means for detecting and determining values indicative of various geometric properties of said contiguous points including the coordinates and angular positions thereof and comparing the same with a plurality of predetermined threshold values, and g. characteristic point storage means for receiving the coordinate and angular positions of said contiguous points which fall within said threshold values.