Abstract: The technology described in this document can be embodied in a method for preventing access to a secure system based on determining a captured image to be of an alternative representation of a live person. The method includes capturing an image of a subject illuminated by an infrared (IR) illumination source, and extracting, from the image, a portion representative of an iris of the subject. The method also includes determining that an amount of high-frequency features in the portion of the image satisfies a threshold condition indicative of the image being of an alternative representation of a live person, and in response, identifying the subject in the image to be an alternative representation of a live person. Responsive to identifying the subject in the image to be an alternative representation of a live person, the method further includes preventing access to the secure system.

Abstract: Technology described herein includes a method that includes receiving, at one or more processing devices, data corresponding to a first image, and determining, by the one or more processing devices based on the received data, that a first set of pixel values of the first image corresponds to illumination of a first representative wavelength, and at least a second set of pixel values of the first image corresponds to illumination of a second representative wavelength. The illuminations of the first and second representative wavelengths constitute at least a portion of a first illumination sequence pattern used in capturing the first image. The method also includes determining that the first illumination sequence pattern matches a second illumination sequence pattern associated with a device from which the first image is expected to be received, and in response, initiating a biometric authentication process for authenticating a subject represented in the first image.

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 receiving, at one or more processing devices, data corresponding to a first set of pixels of an image sensor. The first set of pixels are exposed under illumination by a first source. Data corresponding to a second set of pixels of the image sensor is received, at the one or more processing devices. The second set of pixels are exposed under illumination by a second source that is spatially separated from the first source. A three-dimensional image is generated using the data corresponding to the first set of pixels as a first image of a pair of photometric stereo images, and the data corresponding to the second set of pixels as a second image of the pair of photometric stereo images.

Abstract: Technology described herein includes a method that includes receiving, at one or more processing devices, data corresponding to a first image, and determining, by the one or more processing devices based on the received data, that a first set of pixel values of the first image corresponds to illumination of a first representative wavelength, and at least a second set of pixel values of the first image corresponds to illumination of a second representative wavelength. The illuminations of the first and second representative wavelengths constitute at least a portion of a first illumination sequence pattern used in capturing the first image. The method also includes determining that the first illumination sequence pattern matches a second illumination sequence pattern associated with a device from which the first image is expected to be received, and in response, initiating a biometric authentication process for authenticating a subject represented in the first image.

Abstract: The technology described in this document can be embodied in a method for preventing access to a secure system based on determining a captured image to be of an alternative representation of a live person. The method includes capturing an image of a subject illuminated by an infrared (IR) illumination source, and extracting, from the image, a portion representative of an iris of the subject. The method also includes determining that an amount of high-frequency features in the portion of the image satisfies a threshold condition indicative of the image being of an alternative representation of a live person, and in response, identifying the subject in the image to be an alternative representation of a live person. Responsive to identifying the subject in the image to be an alternative representation of a live person, the method further includes preventing access to the secure system.

Abstract: An underwater camera system for monitoring fish in a fish pen is described. A stereoscopic camera may be used to determine dimensions of fish, and the underwater camera system may use the fish dimensions to estimate a biomass value of fish within the fish pen. The biomass value and rates of change of the biomass value may be used to adjust feeding of the fish in the fish pen. Images captured by the stereoscopic camera may be used to focus a variable focal lens camera on a fish to obtain high-resolution images that can be used for diagnosing fish conditions. Images captured by the stereoscopic camera may be used to predict motion of the fish, and the predicted motion may be used to generate various fish monitoring analytic values. The fish monitoring analytic values may be used to automatically control operation of the fish pen.

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. Responsive to determining that the received electromagnetic radiation is outside the second wavelength range, the method further includes identifying the first subject as an alternative representation of a live person, and preventing access to the secure system in response.

Abstract: In some embodiments, an underwater camera system for monitoring fish in a fish pen is provided. In some embodiments, a stereoscopic camera may be used to determine dimensions of fish, and the underwater camera system may use the fish dimensions to estimate biomass of fish within the fish pen. The biomass value and rates of change of the biomass value may be used to adjust feeding of the fish in the fish pen. In some embodiments, images captured by the stereoscopic camera may be used to focus a variable focal lens camera on a fish to obtain high-resolution images that can be used for diagnosing fish conditions. In some embodiments, images captured by a camera may be used to predict motion of the fish, and the predicted motion may be used to generate various fish monitoring analytic values. The fish monitoring analytic values may be used to automatically control operation of the fish pen.

Abstract: The technology described in this document can be embodied in a method for preventing access to a secure system based on determining a captured image to be of an alternative representation of a live person. The method includes capturing an image of a subject illuminated by an infrared (IR) illumination source, and extracting, from the image, a portion representative of an iris of the subject. The method also includes determining that an amount of high-frequency features in the portion of the image satisfies a threshold condition indicative of the image being of an alternative representation of a live person, and in response, identifying the subject in the image to be an alternative representation of a live person. Responsive to identifying the subject in the image to be an alternative representation of a live person, the method further includes preventing access to the secure system.

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: The technology described in this document can be embodied in a method that includes a method for preventing access to a secure system based on determining a captured image to be of an alternative representation of a live person. The method includes illuminating a subject with structured light using a light source array comprising multiple light sources disposed in a predetermined pattern, capturing an image of the subject as illuminated by the structured light, and determining that the image includes features representative of the predetermined pattern. The method also includes, responsive to determining that the image includes features representative of the predetermined pattern, identifying the subject in the image to be an alternative representation of a live person. The method further includes responsive to identifying the subject in the image to be an alternative representation of a live person, preventing access to the secure system.

Abstract: Technology described herein includes a method that includes receiving, at one or more processing devices, data corresponding to a first image, and determining, by the one or more processing devices based on the received data, that a first set of pixel values of the first image corresponds to illumination of a first representative wavelength, and at least a second set of pixel values of the first image corresponds to illumination of a second representative wavelength. The illuminations of the first and second representative wavelengths constitute at least a portion of a first illumination sequence pattern used in capturing the first image. The method also includes determining that the first illumination sequence pattern matches a second illumination sequence pattern associated with a device from which the first image is expected to be received, and in response, initiating a biometric authentication process for authenticating a subject represented in the first image.

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 receiving, at one or more processing devices, data corresponding to a first set of pixels of an image sensor. The first set of pixels are exposed under illumination by a first source. Data corresponding to a second set of pixels of the image sensor is received, at the one or more processing devices. The second set of pixels are exposed under illumination by a second source that is spatially separated from the first source. A three-dimensional image is generated using the data corresponding to the first set of pixels as a first image of a pair of photometric stereo images, and the data corresponding to the second set of pixels as a second image of the pair of photometric stereo images.

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 receiving, at one or more processing devices, data corresponding to a first set of pixels of an image sensor. The first set of pixels are exposed under illumination by a first source. Data corresponding to a second set of pixels of the image sensor is received, at the one or more processing devices. The second set of pixels are exposed under illumination by a second source that is spatially separated from the first source. A three-dimensional image is generated using the data corresponding to the first set of pixels as a first image of a pair of photometric stereo images, and the data corresponding to the second set of pixels as a second image of the pair of photometric stereo images.

Abstract: Technology described herein includes a method that includes receiving, at one or more processing devices, data corresponding to a first image, and determining, by the one or more processing devices based on the received data, that a first set of pixel values of the first image corresponds to illumination of a first representative wavelength, and at least a second set of pixel values of the first image corresponds to illumination of a second representative wavelength. The illuminations of the first and second representative wavelengths constitute at least a portion of a first illumination sequence pattern used in capturing the first image. The method also includes determining that the first illumination sequence pattern matches a second illumination sequence pattern associated with a device from which the first image is expected to be received, and in response, initiating a biometric authentication process for authenticating a subject represented in the first image.

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: 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: 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 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 for preventing access to a secure system based on determining a captured image to be of an alternative representation of a live person. The method includes capturing an image of a subject illuminated by an infrared (IR) illumination source, and extracting, from the image, a portion representative of an iris of the subject. The method also includes determining that an amount of high-frequency features in the portion of the image satisfies a threshold condition indicative of the image being of an alternative representation of a live person, and in response, identifying the subject in the image to be an alternative representation of a live person. Responsive to identifying the subject in the image to be an alternative representation of a live person, the method further includes preventing access to the secure system.