US 12,321,431 B2
Face authentication anti-spoofing using ultrasound
Octavio Ponce Madrigal, Mountain View, CA (US); Anton Heistser, Munich (DE); and Patrick M. Amihood, Palo Alto, CA (US)
Assigned to Google LLC, Mountain View, CA (US)
Filed by Google LLC, Mountain View, CA (US)
Filed on Sep. 6, 2022, as Appl. No. 17/929,991.
Application 17/929,991 is a continuation of application No. PCT/US2021/056601, filed on Oct. 26, 2021.
Prior Publication US 2023/0126062 A1, Apr. 27, 2023
Int. Cl. G06F 21/32 (2013.01); G06T 7/20 (2017.01); G06T 7/70 (2017.01); G06V 10/25 (2022.01); G06V 10/44 (2022.01); G06V 10/74 (2022.01); G06V 40/16 (2022.01); G06V 40/40 (2022.01)
CPC G06F 21/32 (2013.01) [G06T 7/20 (2013.01); G06T 7/70 (2017.01); G06V 10/25 (2022.01); G06V 10/443 (2022.01); G06V 10/761 (2022.01); G06V 40/161 (2022.01); G06V 40/45 (2022.01); G06T 2207/10132 (2013.01); G06V 2201/07 (2022.01)] 20 Claims
OG exemplary drawing
 
1. A method performed by an ultrasonic sensor, the method comprising:
transmitting an ultrasonic transmit signal;
receiving an ultrasonic receive signal, the ultrasonic receive signal comprising a version of the ultrasonic transmit signal that is reflected by an object;
generating range-profile data based on the ultrasonic receive signal, the range-profile data comprising amplitude information across a range dimension and a time dimension;
generating normalized range-profile data by normalizing the amplitude information within the range-profile data based on a determined distance to the object;
determining a feature associated with the amplitude information of the normalized range-profile data within a region-of-interest that is associated with a location of the object;
detecting a presentation attack based on a comparison of the determined feature to a threshold, the presentation attack attempting to spoof a face-authentication system, the object associated with the presentation attack; and
preventing the face-authentication system from authenticating the presentation attack.