Living body detection device, living body detection method, and recording medium

A living body detection method comprising:

• acquiring a first infrared image in which a subject irradiated by light in a first wavelength range is imaged, a second infrared image in which the subject irradiated by light in a second wavelength range is imaged, and a third infrared image in which the subject irradiated by light in a third wavelength range is imaged, the first, second, and third wavelength ranges being different from each other;
• measuring luminance values of pixels in each of the first, second and third infrared images of the subject;
• counting, using a living body candidate counter, sets of the luminance value of the first infrared image, the luminance value of the second infrared image, and the luminance value of the third infrared image which satisfy a relation exhibit by skin;
• and
• determining whether the subject is a living body or not based on a value indicated by the living body candidate counter.

A non-transitory computer-readable recording medium that stores a program causing a computer to execute:

• acquiring a first infrared image in which a subject irradiated by light in a first wavelength range is imaged, a second infrared image in which the subject irradiated by light in a second wavelength range is imaged, and a third infrared image in which the subject irradiated by light in a third wavelength range is imaged, the first, second, and third wavelength ranges being different from each other;
• measuring luminance values of pixels in each of the first, second and third infrared images of the subject;
• counting, using a living body candidate counter, sets of the luminance value of the first infrared image, the luminance value of the second infrared image, and the luminance value of the third infrared image which satisfy a relation exhibit by skin;
• and
• determining whether the subject is a living body or not based on a value indicated by the living body candidate counter.