Method for recognizing a fake eyeball using lights at two wavelengths
A method for recognizing a fake eyeball using lights at two wavelengths comprises the steps of: illuminating simultaneously an eye region with lights at a first and a second wavelength; acquiring a single image of said eye region of said user, by using an imaging device in which R-color sensing elements, G-color sensing elements and B-color sensing elements are arranged; setting an inspection area by specifying a scleral portion, in said single image; calculating a first color average detection amount by averaging the detection amounts of the first color sensing elements at a location corresponding to said inspection area and a second color average detection amount by averaging the detection amounts of the second color sensing elements at the location corresponding to said inspection area; and calculating a ratio between said first and said second color average detection amounts, and comparing said ratio with a predetermined reference ratio.
1 . A method for recognizing a fake eyeball using lights at two wavelengths, wherein the method is performed by an apparatus for recognizing whether an eye of a user is a fake eyeball by analyzing an eye image of the user, said method comprising:
illuminating simultaneously an eye region including the iris and sclera of a user with a light at a first wavelength and a light at a second wavelength;
acquiring, synchronously with said illuminating, a single image of said eye region of said user, by using an imaging device in which R-color sensing elements, G-color sensing elements and B-color sensing elements are arranged in a Bayer pattern;
setting an inspection area by specifying a scleral portion (E_S), in said single image;
calculating a first color average detection amount by averaging the detection amounts of the first color sensing elements at a location corresponding to said inspection area in said single image and a second color average detection amount by averaging the detection amounts of the second color sensing elements at the location corresponding to said inspection area in said single image; and
calculating a ratio (A average ) between said first color average detection amount and said second color average detection amount, and comparing said ratio (A average ) with a predetermined reference ratio (A Ref ) to determine whether said user's eye is a fake eyeball.
2 . The method according to claim 1 , wherein said first wavelength is selected in the range of 750±50 nm and said second wavelength is selected in the range of 850±50 nm.
3 . The method according to claim 1 , wherein the first color sensing elements are R-color sensing elements, and the second color sensing elements are B-color sensing elements.
4 . The method according to claim 1 , wherein the reference ratio (A Ref ) is a ratio (A average_living ) between a first color average detection amount and a second color average detection amount each measured at a sclera portion (E_S) of the user's eye, and wherein the ratio (A average_living ) have been initially registered by the user to perform the method for recognizing a fake eyeball.
5 . The method according to claim 1 , wherein the reference ratio (A Ref ) is a ratio (A average_artificial ) between a first color average detection amount and a second color average detection amount experimentally measured using an arbitrary fake eyeball in the sclera portion of an arbitrary fake eyeball.