Apparatus and method for identifying fake face
An apparatus for identifying a fake face is provided. A first eye image acquirer acquires a first eye image by taking a picture of a subject while radiating a first ray having a first wavelength. A second eye image acquirer acquires a second eye image by taking a picture of the subject while radiating a second ray having a second wavelength that is shorter than the first wavelength. A controller extracts a first area and a second area having brighter lightness than the first area from each of the first and second eye images, calculates a lightness of the first area and a lightness of the second area in the first eye image, and a lightness of the first area and a lightness of the second area in the second eye image, and determines whether the subject uses a fake face based on the calculated lightness.
1. An apparatus for identifying a fake face, the apparatus comprising:
a first eye image acquirer configured to acquire a first eye image by taking a picture of a subject while radiating a first ray having a first wavelength;
a second eye image acquirer configured to acquire a second eye image by taking a picture of the subject while radiating a second ray having a second wavelength that is shorter than the first wavelength; and
a controller configured to calculate a first lightness of a first area and a second lightness of a second area having brighter lightness than the first area in the first eye image, and a third lightness of the first area and a fourth lightness of the second area having brighter lightness than the first area in the second eye image, and to determine that the subject uses a fake face when amplitude of a high frequency component for a first spatial frequency which is converted from a difference between the first lightness and the second lightness is equal to or greater than amplitude of a high frequency component for a second spatial frequency which is converted from a difference between the third lightness and the fourth lightness, and to determine the subject uses a real face when the amplitude of the high frequency component for the first spatial frequency is less than the amplitude of the high frequency component for the second spatial frequency.
2. The apparatus of claim 1 , wherein the first ray includes an infrared ray, and the second ray includes a visible ray.
3. The apparatus of claim 1 , wherein the first area includes an iris area, and the second area includes a sclera area.
4. The apparatus of claim 1 , wherein the fake face includes any one of an artificial eye, an eye image on a photo, an eye image on a printed page, an eye of a mannequin, or an eye image played by a video.
5. A method of identifying a fake face by a fake face identification apparatus, the method comprising:
acquiring a first eye image by taking a picture of a subject while radiating a first ray having a first wavelength;
acquiring a second eye image by taking a picture of the subject while radiating a second ray having a second wavelength that is shorter than the first wavelength;
extracting a first area and a second area having brighter lightness than the first area from each of the first eye image and the second eye image;
calculating a first lightness of the first area and a second lightness of the second area in the first eye image, and a third lightness of the first area and a fourth lightness of the second area in the second eye image;
converting a difference between the first lightness and the second lightness to a first spatial frequency and a difference between the third lightness and the fourth lightness to a second spatial frequency;
determining the subject uses the fake face when amplitude of a high frequency component for the first spatial frequency is equal to or higher than amplitude of a high frequency component for the second spatial frequency; and
determining the subject uses a real face when the amplitude of the high frequency component for the first spatial frequency is less than the amplitude of the high frequency component for the second spatial frequency.
6. The method of claim 5 , wherein the first ray includes an infrared ray, and the second ray includes a visible ray.
7. The method of claim 5 , wherein the first area includes an iris area, and the second area includes a sclera area.
8. The method of claim 5 , wherein the fake face includes any one of an artificial eye, an eye image on a photo, an eye image on a printed page, an eye of a mannequin, or an eye image played by a video.
9. The method of claim 5 , further comprising storing the first lightness, the second lightness, the third lightness, the fourth lightness, and a determining result of the controller.