Differentiating real faces from representations

摘要

Facial recognition can be used to determine whether or not a user has access privileges to a device such as a smartphone. It may be possible to spoof an authenticated user's image using a picture of the user. Implementations disclosed herein utilize time of flight and/or reflectivity measurements of an authenticated user to compare to such values obtained for an image of an object. If the time of flight distance and/or reflectivity distance for the object match a measured distance, then the person (i.e., object) may be granted access to the device.

主权项

1. A method, comprising:
emitting light from a device toward an object; capturing an image of the object using a sensor, comprising receiving the light by the sensor; identifying at least two landmarks within the image of the object; determining a number of pixels in the image disposed between the at least two landmarks; determining a measured distance between the device and the object based on the number of pixels; determining a reflectivity distance between the device and the object based on an amount of light received by the sensor; determining a time of flight distance between the device and the object; comparing the time of flight distance, the reflectivity distance, and the measured distance; determining whether the object is authorized to operate the device based on the comparison of the time of flight distance, the reflectivity distance, and the measured distance; and providing an access level to the device based on the determination of whether the object is authorized to operate the device.