Abstract: The technology described in this document can be embodied in a method for verifying an authenticated state of a device. In one aspect, the method includes capturing, during a primary authentication process, first auxiliary user identifying information for short-term authentication verification of the subject. The first auxiliary user identifying information includes first eyebrow biometric information for the subject and first eyeglass frame information for the subject. A short-term authentication verification process is performed to verify identify of the subject. In response to determining that a match score that indicates a degree of match between the first auxiliary user identifying information and captured second auxiliary user identifying information meets or exceeds a predetermined threshold, an authenticated state for the subject is verified. In response to determining that the match score does not meet or exceed the predetermined threshold, the authenticated state for the subject is ended.

Abstract: The technology described in this document can be embodied in a method for verifying an authenticated state of a device. In one aspect, the method includes capturing, during a primary authentication process, first auxiliary user identifying information for short-term authentication verification of the subject. The first auxiliary user identifying information includes first eyebrow biometric information for the subject and first eyeglass frame information for the subject. A short-term authentication verification process is performed to verify identify of the subject. In response to determining that a match score that indicates a degree of match between the first auxiliary user identifying information and captured second auxiliary user identifying information meets or exceeds a predetermined threshold, an authenticated state for the subject is verified. In response to determining that the match score does not meet or exceed the predetermined threshold, the authenticated state for the subject is ended.

Abstract: The technology described in this document can be embodied in a method that includes receiving from a sensor, information indicative of an environmental condition. The method also includes receiving first information indicative of whether or not a first image captured by a first image acquisition device corresponds to an alternative representation of a live person, and receiving second information indicative of whether or not a second image captured by a second image acquisition device corresponds to the alternative representation. The first information and the second information are combined in a weighted combination, the corresponding weights being assigned in accordance with the environmental condition. A determination is made, based on the weighted combination, that a subject in the first and second images is an alternative representation of a live person, and in response, access to the secure system is prevented.

Abstract: The technology described in this document can be embodied in a method that includes receiving during a first time period, information from a first sensor representing a target illuminated by a first illumination source radiating in a first wavelength range, and information from a second sensor representing the target illuminated by a second illumination source radiating in a second wavelength range. The method also includes receiving during a second time period, information from the first sensor representing the target illuminated by the second illumination source radiating in the first wavelength range, and information from the second sensor representing reflected light received from the target illuminated by the first illumination source radiating in the second wavelength range. The method also includes generating a representation of the image in which effects due to the first and second illumination sources are enhanced over effects due to ambient light sources.

Abstract: The technology described in this document can be embodied in a method that includes receiving during a first time period, information from a first sensor representing a target illuminated by a first illumination source radiating in a first wavelength range, and information from a second sensor representing the target illuminated by a second illumination source radiating in a second wavelength range. The method also includes receiving during a second time period, information from the first sensor representing the target illuminated by the second illumination source radiating in the first wavelength range, and information from the second sensor representing reflected light received from the target illuminated by the first illumination source radiating in the second wavelength range. The method also includes generating a representation of the image in which effects due to the first and second illumination sources are enhanced over effects due to ambient light sources.

Abstract: This document described a method that includes illuminating a first subject with electromagnetic radiation in a first wavelength range, and capturing a first image of the first subject under illumination of the first wavelength range. The method also includes illuminating the first subject with electromagnetic radiation in a second wavelength range, wherein a difference between (i) absorption of the second wavelength range by live human tissue, and (ii) absorption of the first wavelength range by live human tissue satisfies a threshold condition. The method further includes capturing a second image of the first subject under illumination of the second wavelength range, identifying, based on a difference between the first image and the second image, the first subject as an alternative representation of a live person, and preventing access to the secure system responsive to identifying the first subject as an alternative representation of a live person.

Abstract: In a feature extraction and pattern matching system, image sharpening can enable vascular point detection (VPD) for detecting points of interest from visible vasculature of the eye. Pattern Histograms of Extended Multi-Radii Local Binary Patterns and/or Pattern Histograms of Extended Multi-Radii Center Symmetric Local Binary Patterns can provide description of portions of images surrounding a point of interest, and enrollment and verification templates can be generated using points detected via VPD and the corresponding descriptors. Inlier point pairs can be selected from the enrollment and verification templates, and a first match score indicating similarity of the two templates can be computed based on the number of inlier point pairs and one or more parameters of a transform selected by the inlier detection. A second match score can be computed by applying the selected transform, and either or both scores can be used to authenticate the user.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for determining the identity of a user. In one aspect, a method comprises: obtaining at least one image depicting a reflection of light from a lens that is included in a set of eyeglasses; determining, based on the reflection of light from the lens, a set of features characterizing the lens; and determining an identity of a corresponding user based at least in part on the set of features characterizing the lens.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for capacitive through-body communication. In one aspect, a method includes capturing, from capacitive through-body communication with an on-body device worn by an individual, a biometric template comprising identification data associated with the individual, comparing the captured identification data of the captured biometric template with reference identification data of a stored biometric template associated with the individual, determining that the captured identification data matches the reference identification data of the stored biometric template; and authenticating identification of the individual.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for a biometric authentication system. In one aspect, a method includes identifying a target user in proximity to a kiosk. Data for the target user is gathered from equipment on and in proximity to the kiosk. The gathered data is processed to generate a feature vector. The feature vector includes at least motion characteristics of the target user as the target user approaches the kiosk and touch input characteristics of the target user at the kiosk. A candidate user to compare to the target user is determined. Reference data for the candidate user is retrieved. The feature vector is compared to the reference data for the candidate user to determine a likelihood that the target user is the candidate user. A kiosk application is customized for the target user based on the determined likelihood.

Abstract: The technology described in this document can be embodied in a method for preventing access to a secure system based on determining that a subject is an alternative representation of a live person. The method includes illuminating a first subject with electromagnetic radiation using a first wavelength range that cause fluorescence in human tissue. The fluorescence is in a second wavelength range different from the first wavelength range. The method also includes receiving, responsive to illuminating the first subject and using one or more sensors, electromagnetic radiation emitted from the first subject, and determining that the received electromagnetic radiation is outside the second wavelength range.

Abstract: The technology described in this document can be embodied in a method for generating an iris identifier. The method includes obtaining a plurality of images of an iris, and generating a binary code for each of the plurality of images of the iris, the binary code including a sequence of bits. The method also includes identifying a first pattern of bits for which bit values and bit-locations are the same across a plurality of the binary codes, generating a first index based on the first pattern of bits, and then storing the first index on a storage device in accordance with a database management system. The first index is linked to biometric information of a different modality for a corresponding user.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for a biometric authentication system. In one aspect, a method includes broadcasting, through a transceiver, a signal that includes a kiosk identifier; receiving, from a server system, a reference image of the user based on a mobile computing device associated with the user having received the signal and providing the kiosk identifier to the server system; capturing, with a camera, an image of the user; and authenticating the user based on a comparison of the captured image of the user to the reference image of the user based on a comparison of the captured image of the user to the reference image of the user.

Abstract: The technology described in this document can be embodied in a method that includes receiving during a first time period, information from a first sensor representing a target illuminated by a first illumination source radiating in a first wavelength range, and information from a second sensor representing the target illuminated by a second illumination source radiating in a second wavelength range. The method also includes receiving during a second time period, information from the first sensor representing the target illuminated by the second illumination source radiating in the first wavelength range, and information from the second sensor representing reflected light received from the target illuminated by the first illumination source radiating in the second wavelength range. The method also includes generating a representation of the image in which effects due to the first and second illumination sources are enhanced over effects due to ambient light sources.

Abstract: In a feature extraction and pattern matching system, image sharpening can enable vascular point detection (VPD) for detecting points of interest from visible vasculature of the eye. Pattern Histograms of Extended Multi-Radii Local Binary Patterns and/or Pattern Histograms of Extended Multi-Radii Center Symmetric Local Binary Patterns can provide description of portions of images surrounding a point of interest, and enrollment and verification templates can be generated using points detected via VPD and the corresponding descriptors. Inlier point pairs can be selected from the enrollment and verification templates, and a first match score indicating similarity of the two templates can be computed based on the number of inlier point pairs and one or more parameters of a transform selected by the inlier detection. A second match score can be computed by applying the selected transform, and either or both scores can be used to authenticate the user.

Abstract: Techniques are described for authentication using sound-based monitor detection. In some implementations, the sound (e.g., ultrasound) generated by a monitor is used to detect its presence in the vicinity of a (e.g., portable) computing device that is being used to capture image(s) to be provided to an image-based authentication system. While the computing device is being used to capture image(s) to be provided to the image-based authentication system, the sound data in proximity to the computing device can be captured and analyzed (e.g., using machine learning or other techniques) to determine whether the sound data exhibits a particular pattern and/or characteristics (e.g., signature) that indicates the presence of a monitor in proximity to the computing device. The presence (or absence) of a monitor can be used in determining whether to authenticate the user.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for a biometric authentication system. In one aspect, a method includes, a vibrating component of a mobile device is vibrated; a vibration signal of the mobile device is detected as a user grips the mobile device; a dynamic grip signature is determined for the user based on the detected vibration signal; and the user is authenticated based on a comparison of the dynamic grip signature to an initial grip template.

Abstract: Techniques are described for user authentication based on correlation of multiple pulse signals that each describe an independently determined pulse pattern for an individual. Different measurements of an individual's pulse can be generated in response to a request from the individual to access a computing system, such as a kiosk. The different measurements can be generated independently of one another using different types of sensor devices. For example, a measurement can be made using a radar sensor to detect movements caused by the user's pulse, and another measurement can be made through analysis of video data. If the independently generated pulse patterns are sufficiently similar to each other (e.g., determined using machine learning or other techniques), a determination may be made that the individual is not attempting to spoof another individual, and access to the computing system can be granted based at least partly on the determination.

Abstract: The technology described in this document can be embodied in a computer-implemented method that includes receiving, at one or more servers from a first computing device, (i) first identification information identifying the first computing device or an application executing on the first computing device, and (ii) second identification information identifying a second computing device. The second identification information is obtained by the first computing device by detecting changes to one or more parameters of a magnetic field generated by the second computing device. The method also includes determining, by the server based on the first information, identity information of a user associated with the first computing device, and transmitting, from the one or more servers to the second computing device, the identity information, such that the identity information is usable by the second computing device to verify an access attempt by the user.

Abstract: In a feature extraction and pattern matching system, image sharpening can enable vascular point detection (VPD) for detecting points of interest from visible vasculature of the eye. Pattern Histograms of Extended Multi-Radii Local Binary Patterns and/or Pattern Histograms of Extended Multi-Radii Center Symmetric Local Binary Patterns can provide description of portions of images surrounding a point of interest, and enrollment and verification templates can be generated using points detected via VPD and the corresponding descriptors. Inlier point pairs can be selected from the enrollment and verification templates, and a first match score indicating similarity of the two templates can be computed based on the number of inlier point pairs and one or more parameters of a transform selected by the inlier detection. A second match score can be computed by applying the selected transform, and either or both scores can be used to authenticate the user.