Patent ID: 7239751

Claim:
A method of recognizing a pattern in an image comprising the steps of: (a) receiving data characterizing the pattern in pattern coordinate space; (b) selecting feature points for the pattern; (d) transforming the pattern from pattern coordinate space to a parameter space by creating a parameter table characterizing the pattern wherein pairs of feature points of the pattern are parameterized as a set of vectors with respect to at least two reference points; (e) receiving data representing the image; (f) extracting points of interest from the image data utilizing a low level vision process; (g) initializing a parameter space accumulator comprising an array of cells; (h) selecting pairs of extracted points parallel to each other in respect of their gradient angle and parameterizing the pairs of extracted points; (i) comparing the values computed for pairs of extracted points with the parameter table and incrementing the cells of the parameter space accumulator corresponding to matching parameter values; and (j) processing relative peaks in the accumulator array to determine a match with the desired template object.