Abstract: In accordance with some embodiments, various examples of systems, methods, and media for single photon depth imaging with improved efficiency using learned compressive representations are provided. For example, systems and methods herein may detect a photon arrival based on a signal from a detector at a given position and time bin. A compressed histogram comprising K stored values, representing bins of the compressed histogram based on K values in a code word calculated based on the time bin and position and K coding tensors. Such systems and methods may be utilized for, among other uses, determining depth in a scene being imaged by the detector.

Abstract: In accordance with some embodiments, systems, methods and media for single photon depth imaging with improved precision in ambient light conditions are provided. In some embodiments, the system comprises: a light source; a single photon detector; an attenuation element configured to provide a variable intensity attenuation factor; and a processor programmed to: (a)-determine an ambient light intensity associated with a scene point; (b)-select an attenuation factor based on the ambient light intensity; (c)-estimate a depth of the scene point based on a multiplicity of photon arrival times determined using the detector during a period of time during which light incident on the detector is attenuated by the selected attenuation factor and during which the light source is configured to periodically emit a pulse of light toward the scene point; (d)-repeat (a)-(c) for each of a multiplicity of scene points.

Abstract: In accordance with some embodiments, systems, methods, and media for high dynamic range imaging using single-photon and conventional image sensor data are provided. In some embodiments, the system comprises: first detectors configured to detect a level of photons proportional to incident photon flux; second detectors configured to detect arrival of individual photons; a processor programmed to: receive, from the first detectors, first values indicative of photon flux from a scene with a first resolution; receive, from the second detectors, second values indicative of photon flux from the scene with a lower resolution; provide a first encoder of a trained machine learning model first flux values based on the first values, provide the second encoder of the model second flux values; receive, as output, values indicative of photon flux from the scene; and generate a high dynamic range image based on the third plurality of values.

Abstract: In accordance with some embodiments, systems, methods, and media for estimating a depth and orientation of a portion of a scene using a single-photon detector and diffuse light source are provided. In some embodiments, a system comprises: a light source; an image sensor comprising a pixel having a field of view of at least one degree; a hardware processor programmed to: cause the light source to emit a sequence of n defocused pulses toward the scene; receive, from the pixel, information indicative of arrival times of light from the scene; generate a transient histogram using the information indicative of arrival times of light from the scene; and estimate one or more properties of a portion of the scene within the field of view of the pixel based on the transient histogram, wherein the one or more properties of the portion of the scene includes at least a depth.

Abstract: In accordance with some embodiments, systems, methods, and media for single photon depth imaging with improved efficiency using compressive histograms are provided. In some embodiments, the system comprises: a light source; a detector configured to detect arrival of individual photons; a processor programmed to: detect a photon arrival; determine a time bin i of the photon arrival in a range from 1 to N a total number of time bins; update a compressed histogram comprising K stored values representing bins of the compressed histogram based on K values in a code word represented by an ith column of a coding matrix C having dimension K×N, with each column different than each other column, and each column corresponds to a single time bin i; and estimate a depth value based on the K values.

Abstract: In accordance with some embodiments, systems, methods, and media for high dynamic range imaging using single-photon and conventional image sensor data are provided. In some embodiments, the system comprises: first detectors configured to detect a level of photons proportional to incident photon flux; second detectors configured to detect arrival of individual photons; a processor programmed to: receive, from the first detectors, first values indicative of photon flux from a scene with a first resolution; receive, from the second detectors, second values indicative of photon flux from the scene with a lower resolution; provide a first encoder of a trained machine learning model first flux values based on the first values, provide the second encoder of the model second flux values; receive, as output, values indicative of photon flux from the scene; and generate a high dynamic range image based on the third plurality of values.

Abstract: Real time strain imaging is provided by acquiring a sequence of cardiac image frames and estimating tissue displacement in the myocardium over a heart cycle. The displacements are used to calculate strain over the myocardium and a color map is formed of the strain values. During the next heart cycle the color map is warped to fit the myocardium in each image frame and the warped color map is displayed as a color overlay over the myocardium of each image of the new heart cycle as they are displayed in real time. A new color map is also produced over the new heart cycle for use with the following heart cycle. An ultrasound system which performs real time strain imaging is also described.

Abstract: In accordance with some embodiments, systems, methods, and media for high dynamic range imaging using single-photon and conventional image sensor data are provided. In some embodiments, the system comprises: first detectors configured to detect a level of photons proportional to incident photon flux; second detectors configured to detect arrival of individual photons; a processor programmed to: receive, from the first detectors, first values indicative of photon flux from a scene with a first resolution; receive, from the second detectors, second values indicative of photon flux from the scene with a lower resolution; provide a first encoder of a trained machine learning model first flux values based on the first values, provide the second encoder of the model second flux values; receive, as output, values indicative of photon flux from the scene; and generate a high dynamic range image based on the third plurality of values.

Abstract: In accordance with some embodiments, systems, methods, and media for motion adaptive imaging using single-photon image sensor data are provided. In some embodiments, the system comprises: an image sensor comprising single-photon detectors in an array; a processor programmed to: receive a sequence of photon frames, each comprising pixels having a value indicative of whether a photon was received during a frame period, each of the pixels corresponds to a pixel location; identify, for each of the pixel locations, changepoints, each indicative of a change in scene brightness; identify a photon frame in the sequence at which at least a threshold change in brightness has occurred based on the changepoints associated with each of the plurality of pixel locations; and generate a series of changepoint frames, wherein each changepoint frame is based on estimated brightness associated with each pixel location at a point in the sequence of photon frames.

Abstract: In accordance with some embodiments, systems, methods, and media for asynchronous single photon depth imaging with improved precision in ambient light conditions are provided. In some embodiments, the system comprises: a light source; a detector configured to detect arrival of individual photons, and enter a dead time after a detection; a processor programmed to: cause the light source to emit pulses toward a scene point at the beginning of light source cycles each corresponding to B time bins; cause the detector to enter an acquisition window at a first time bin position; cause the detector to enter another acquisition window at a shifted time bin position; record photon arrival times; associate each photon arrival time with a time bin; and estimate a depth of the scene point based on a number of photon detection events at each time bin, and a denominator corresponding to each time bin.

Abstract: Real time strain imaging is provided by acquiring a sequence of cardiac image frames and estimating tissue displacement in the myocardium over a heart cycle. The displacements are used to calculate strain over the myocardium and a color map is formed of the strain values. During the next heart cycle the color map is warped to fit the myocardium in each image frame and the warped color map is displayed as a color overlay over the myocardium of each image of the new heart cycle as they are displayed in real time. A new color map is also produced over the new heart cycle for use with the following heart cycle. An ultrasound system which performs real time strain imaging is also described.

Abstract: Real time strain imaging is provided by acquiring a sequence of cardiac image frames and estimating tissue displacement in the myocardium over a heart cycle. The displacements may be estimated using speckle tracking and are used to calculate strain over the myocardium. A color map is formed of the strain values. During the next heart cycle the color map is warped to fit the myocardium in each image frame and the warped color map is displayed as a color overlay over the myocardium of each image of the new heart cycle as they are displayed in real time. A new color map is also produced over the new heart cycle for use with the following heart cycle. An ultrasound system which performs real time strain imaging is also described.

Abstract: In accordance with some embodiments, systems, methods, and media for asynchronous single photon depth imaging with improved precision in ambient light conditions are provided. In some embodiments, the system comprises: a light source; a detector configured to detect arrival of individual photons, and enter a dead time after a detection; a processor programmed to: cause the light source to emit pulses toward a scene point at the beginning of light source cycles each corresponding to B time bins; cause the detector to enter an acquisition window at a first time bin position; cause the detector to enter another acquisition window at a shifted time bin position; record photon arrival times; associate each photon arrival time with a time bin; and estimate a depth of the scene point based on a number of photon detection events at each time bin, and a denominator corresponding to each time bin.

Abstract: In accordance with some embodiments, systems, methods and media for single photon depth imaging with improved precision in ambient light conditions are provided. In some embodiments, the system comprises: a light source; a single photon detector; an attenuation element configured to provide a variable intensity attenuation factor; and a processor programmed to: (a)-determine an ambient light intensity associated with a scene point; (b)-select an attenuation factor based on the ambient light intensity; (c)-estimate a depth of the scene point based on a multiplicity of photon arrival times determined using the detector during a period of time during which light incident on the detector is attenuated by the selected attenuation factor and during which the light source is configured to periodically emit a pulse of light toward the scene point; (d)-repeat (a)-(c) for each of a multiplicity of scene points.

Abstract: Real time strain imaging is provided by acquiring a sequence of cardiac image frames and estimating tissue displacement in the myocardium over a heart cycle. The displacements may be estimated using speckle tracking and are used to calculate strain over the myocardium. A color map is formed of the strain values. During the next heart cycle the color map is warped to fit the myocardium in each image frame and the warped color map is displayed as a color overlay over the myocardium of each image of the new heart cycle as they are displayed in real time. A new color map is also produced over the new heart cycle for use with the following heart cycle. An ultrasound system which performs real time strain imaging is also described.