Patent ID: 7095880

Claim:
A method for rolled fingerprint capture, comprising the steps of: (1) detecting the start of a fingerprint roll; (2) capturing a plurality of fingerprint image frames; (3) determining a centroid window corresponding to each of the plurality of captured fingerprint image frames, including the steps of: (a) generating a pixel window in a captured fingerprint image frame; (b) finding a leading edge column and a trailing edge column of a fingerprint image in the corresponding generated pixel window, including the steps of: (i) building a histogram representative of the cumulative pixel intensity of pixels present in each column of the generated window; (ii) scanning through the histogram in the direction opposite that in which the finger is rolled for a difference in the total pixel intensities of first adjacent columns of the generated pixel window that is greater than a first fingerprint edge threshold to find a leading edge; and (iii) scanning through the histogram in the direction in which the finger is rolled for a difference in the total pixel intensities of second adjacent columns of the generated pixel window that is greater than a second fingerprint edge threshold to find a trailing edge; and (c) generating the centroid window in the captured fingerprint image frame, wherein the centroid window is bounded by the leading edge column found and the trailing edge column found; (4) knitting pixels of each determined centroid window into a composite fingerprint image; and (5) detecting the end of said fingerprint roll.