Face Recognition Reinforcement using Pulse Waves of Front Camera Face Image and Rear Camera Finger Image on a Smartphone

Face authentication technology is a common form of smartphone user authentication. There is a vulnerability in face authentication that a malicious person can exploit. Various security measures have been implemented to prevent face authentication from being breached by a sleeping registered user, photo and 3D mask. This paper proposes a method to develop a system that can authenticate a registered user only when they perform face authentication of their volition. The method involves normal face authentication and obtaining two pulse wave data from the front camera face image and the rear camera finger image. Peaks and valleys are identified from the sampled pulse wave data of the face and finger. Pairs of peaks and valleys from the two pulse wave data are then formed. If the sum of the average time differences between a pair of peaks and a pair of valleys falls within the threshold values, the system determines that the face and finger belong to the same owner. The evaluation experiment was conducted under three distinct lighting conditions: a ring light environment, a smartphone light environment, and a natural light environment. The best EER value reached 0.005 using 5-second pulse wave data in the ring light environment.