Patent ID: 7676063

Claim:
A process for tracking eyes and detecting eye blinks, comprising the process actions of: using a computing device for, defining eye templates for a person depicted in a video frame; inputting a video frame of the person's face; using a face detector to find a face box which surrounds the face of the person; searching the upper part of the face box for eyes using feature based matching to match image patches for each eye in the video frame to the eye templates to locate the eyes, wherein the feature based matching comprises the process actions of: for each image patch, computing a grayscale image corresponding to the image patch; creating horizontal and vertical edge maps of the image patch; summing columns of pixels for the grayscale image and the vertical edge map to project the image patch to the horizontal axis to create two one dimensional (1D) signals; summing rows of pixels for the horizontal edge map to project the image patch to the vertical axis to produce one 1D signal; and computing the similarity between the eye template and the image patch as a weighted sum of the correlations between corresponding 1D signals, wherein the similarity is determined by a signal correlation function S(A,B) of S ⁢ ( A , B ) = ∑ i = 1 L ⁢ ( a i ⁢ b i ) / ∑ i = 1 L ⁢ a i 2 ⁢ ∑ i = 1 L ⁢ b i 2 where L is the length of the signal and signals A and B are two arrays, A=a 1 , a 2 , . . . , a L , B=b 1 , b 2 , . . . , b L where a i and b i are elements in the two arrays.