Patent ID: 7650034

Claim:
A method of identifying eye candidates in a video image of a human subject, comprising the steps of: (a) identifying a face-blob region of the image that includes all contiguous facial skin of the subject; (b) selecting a subset of said face-blob region that is most likely to include the subject's eyes; (c) projecting horizontal rows of pixels in said subset and selecting a row of maximal receptive hole content; (d) identifying each black pixel in the selected row as an eye candidate center; (e) for each identified black pixel, determining a receptive hole count in a vertical column of pixels including the black pixel, and selecting the black pixels for which the determined receptive hole count is less than a predetermined threshold; (f) forming potential eye candidates for each of the selected black pixels by extracting eye-sized patches of said image centered on the selected black pixels; (g) appearance testing the potential eye candidates and selecting the potential eye candidates that satisfy an eye appearance criterion; (h) pairing selected potential eye candidates that are separated by less than a predetermined distance, and of the paired potential eye candidates, retaining a single eye candidate that best satisfies said eye appearance criterion; (i) testing the retained potential eye candidates based on spatial and anthropomorphic considerations to select one or more winning eye candidates; (j) accumulating a tabulation of winning eye candidate locations for a series of successively produced video images; (k) comparing a location of a winning eye candidate from a current video image to said tabulation of said winning eye candidate locations; (l) accepting the winning eye candidate from the current video image if its location compares favorably to said tabulation of said winning eye candidate locations; (m) dividing the accumulated tabulation of winning eye candidate locations, including the location of the winning eye candidate from the current video image, into two clusters by their location; and (n) if the location of the winning eye candidate from the current video image does not compare favorably to the locations of said two clusters, selecting the cluster including the location of the winning eye candidate from the current video image, dividing the selected cluster into two new clusters by their location, and evaluating the winning eye candidate from the current video image based on its location relative to locations of the two new clusters to determine if it should be accepted.