CPC G06V 40/1306 (2022.01) [G06F 21/32 (2013.01); G06V 10/82 (2022.01); G06V 40/1376 (2022.01); G06V 40/45 (2022.01); G06V 40/50 (2022.01)] | 20 Claims |
11. A method, comprising:
controlling, by a control system, an ultrasonic fingerprint sensor system to obtain current A-line data from a target object on an outside surface of an apparatus that includes the ultrasonic fingerprint sensor system, the current A-line data comprising fingerprint sensor data corresponding to reflections of ultrasonic waves from the target object detected by a single receiver pixel or by a cluster of adjacent receiver pixels;
controlling, by the control system, the ultrasonic fingerprint sensor system to obtain current ultrasonic fingerprint image data corresponding to reflections of ultrasonic waves from a target object surface;
obtaining, by the control system and from a memory system, previously-obtained A-line data, the previously-obtained A-line data having previously been obtained by the ultrasonic fingerprint sensor system and from an authorized user;
obtaining, by the control system and from the memory system, previously-obtained ultrasonic fingerprint image data, the previously-obtained ultrasonic fingerprint image data having previously been obtained by the ultrasonic fingerprint sensor system and from the authorized user; and
estimating, by the control system and based at least in part on the current A-line data, the previously-obtained A-line data, the current ultrasonic fingerprint image data and the previously-obtained ultrasonic fingerprint image data, whether the target object is a finger of the authorized user, wherein estimating whether the target object is a finger of the authorized user involves an anti-spoofing process performed by one or more neural networks including a deep neural network (DNN) and a plurality of multilayer perceptrons (MLPs), each of the MLPs being configured to provide output features to the DNN corresponding to a frame of current A-line data and a frame of previously-obtained A-line data.
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