67 results about "Compressive imaging" patented technology

A compressive imaging (CI) device including a light modulator and a light sensor (e.g., a single-element sensor or a sensor array). The CI device may support the focusing of light on the light modulator and / or on the light sensor in a number of ways: (1) determining a focus indicator value by analyzing a 1D or 2D image in the incident light field; (2) measuring light spillover between modulator regions and light sensing elements—either at the level of voltage measurements or the level of reconstructed images; (3) measure noise in reconstructed sub-images; (4) measuring an amount high-frequency content in the incident light field; (5) incorporating a range finder to measure distance to the object being imaged; (6) incorporating an image sensor downstream from the modulator; and (7) splitting a portion of the incident light onto an image sensor, prior to the modulator.

A compressive imaging system and method for quickly detecting spectrally and spatially localized events (such as explosions or gun discharges) occurring within the field of view. An incident light stream is modulated with a temporal sequence of spatial patterns. The wavelength components in the modulated light stream are spatially separated, e.g., using a diffractive element. An array of photodetectors is used to convert subsets of the wavelength components into respective signals. An image representing the field of view may be reconstructed based on samples from some or all the signals. A selected subset of the signals are monitored to detect event occurrences, e.g., by detecting sudden changes in intensity. When the event is detected, sample data from the selected subset of signals may be analyzed to determine the event location within the field of view. The event location may be highlighted in an image being generated by the imaging system.

A system and method for searching an incident light field for atypical regions (e.g., hot spots or cool spots or spectrally distinctive regions) within the incident light field using a light modulator and a spectral sensing device. Once the atypical regions are identified, the light modulator may be used to mask the incident light field so that the spectral sensing device can make spatially-concentrated measurements of the wavelength spectrum of the atypical regions (or alternatively, the exterior of the atypical regions). Furthermore, in a compressive imaging mode, a sequence of spatial patterns may be supplied to the light modulator, and a corresponding sequence of wavelength spectra may be collected from the spectral sensing device. The wavelength spectra comprise a compressed representation of the incident light field over space and wavelength. The wavelength spectra may be used to reconstruct a multispectral (or hyperspectral) data cube.

A compressive imaging system modulates an incident light stream and senses the modulated light stream to obtain compressive measurements. The measurements are algorithmically processed to reconstruct a sequence of images. The image sequence is displayed. The system receives user input (through a user interface) representing a user command to set or change one or more visual performance factors such as image quality and frame rate. The system immediately adjusts the visual performance factors by adjusting one or more underlying system parameters / algorithms. Thus, the visual consequences of any inputs to the user interface become immediately apparent in the displayed sequence of images. The user may therefore intuitively learn how to operate the user interface simply by making trial inputs and observing their effects in the displayed image sequence. The user interface may include one or more mechanical input devices and / or one or more graphical user interface (GUI) elements.

An imaging system and method that captures compressive sensing (CS) measurements of a received light stream, and also obtains samples of background light level (BGLL). The BGLL samples may be used to compensate the CS measurements for variations in the BGLL. The system includes: a light modulator to spatially modulate the received light stream with spatial patterns, and a lens to concentrate the modulated light stream onto a light detector. The samples of BGLL may be obtained in various ways: (a) injecting calibration patterns among the spatial patterns; (b) measuring complementary light reflected by digital micromirrors onto a secondary output path; (c) separating and measuring a portion of light from the optical input path; (d) low-pass filtering the CS measurements; and (e) employing a light power meter with its own separate input path. Also, the CS measurements may be high-pass filtered to attenuate background light variation.

A compressive imaging system for optimizing dynamic range during the acquisition of compressed images. A light modulator modulates incident light with spatial patterns to produced modulated light. A light sensing device generates an electrical signal representing intensity of the modulated light over time. The system amplifies a difference between the electrical signal and an adjustable baseline voltage and captures samples of the amplified signal. The adjustable baseline voltage is set to be approximately equal to the average value of the electrical signal. A compressive imaging system for identifying and correcting hot spot(s) in the incident light field. Search patterns are sent to the light modulator and the corresponding samples of the electrical signal are analyzed. Once the hot spot is located, the light modulating elements corresponding to the hot spot may be turned off or their duty cycle may be reduced.

A compressive imaging system including a light modulator, a light sensing device and a TIR prism. The TIR prism is configured to receive an incident light beam, to provide the incident light beam to the light modulator, to receive a modulated light beam MLB from the light modulator, and to direct the modulated light beam onto a sensing path. The light sensing device receives the modulated light beam (or at least a portion of the modulated light beam) and generates an electrical signal that represents intensity of the modulated light beam (or the “at least a portion” of the modulated light beam). The TIR prism may reduce a distance required to separate the incident light beam from the modulated light beam.

A compressive imaging system includes an illumination system arranged to illuminate an object of interest with illumination light, and a detection system configured to detect at least a portion of the illumination light after being at least one of reflected from, scattered from, or transmitted through the object of interest or to detect fluorescent light from the object of interest and to provide an imaging signal. The compressive imaging system further includes an image processing system configured to communicate with the detection system to receive the imaging signal. The illumination light from the illumination system comprises a plurality of light pulses such that each light pulse has a preselected spectrum that is distinguishable from spectra of all other pulses. The image processing system is configured to form an image of the object of interest using information concerning the preselected spectra of the plurality of light pulses.

An imaging system and method that captures compressive sensing (CS) measurements of a received light stream, and also obtains samples of background light level (BGLL). The BGLL samples may be used to compensate the CS measurements for variations in the BGLL. The system includes: a light modulator to spatially modulate the received light stream with spatial patterns, and a lens to concentrate the modulated light stream onto a light detector. The samples of BGLL may be obtained in various ways: (a) injecting calibration patterns among the spatial patterns; (b) measuring complementary light reflected by digital micromirrors onto a secondary output path; (c) separating and measuring a portion of light from the optical input path; (d) low-pass filtering the CS measurements; and (e) employing a light power meter with its own separate input path. Also, the CS measurements may be high-pass filtered to attenuate background light variation.

Compressive imaging apparatus employing multiple modulators in various optical schemes to generate the modulation patterns before the signal is recorded at a detector. The compressive imaging apparatus is equally valid when applying compressive imaging to structured light embodiments where the placement is shifted from the acquisition path between the subject and the detector into the illumination path between the source and the subject to be imaged.

The invention discloses a terahertz compressive imaging system and method. The system comprises 1, a terahertz generation and detection unit which comprises a laser source, a terahertz emitter and a terahertz detector, 2, a terahertz wave coding measurement unit which comprises a light splitter lens, a semiconductor mask plate and a digital projection device, wherein the digital projection device produces encoded pattern light beams, the light beams act on the semiconductor mask plate to cause semiconductor carrier distribution and the semiconductor mask plate allows the specific terahertz wave to go through the mask plate and keeps congruity of the specific terahertz wave and the light beam pattern so that terahertz wave spatial modulation is realized and a semiconductor mask plate coding function is realized, and 3, a terahertz reconstruction imaging unit which is used for recovering the original image through a reconstruction algorithm so that terahertz imaging is realized. Through combination of digital light processing projection and semiconductor photo-induced carrier characteristics, terahertz wave light-controlled modulation is realized. The system has the advantages of complete digitization, fast rate, high programmable capability, low cost and integration easiness.

Mechanisms for increasing the rate of acquisition of compressed / encoded image representations are disclosed. An imaging system may deliver subsets of a modulated light stream onto respective light sensing devices. The light sensing devices may be sampled in parallel. Samples from each light sensing device may be used to construct a respective sub-image of a final image. The parallelism allows compressed images to be acquired at a higher rate. The number of light sensing devices and / or the number of pixels per image may be selected to achieve a target image acquisition rate. In another embodiment, spatial portions of the incident light stream are separated and delivered to separate light modulators. In yet another embodiment, the incident light stream is split into a plurality of beams, each of which retains the image present in the incident light stream and is delivered to a separate light modulator.

A compressive imaging mechanism for increasing the rate at which images can be acquired and reconstructed. An incident light stream is modulated with a time sequence of spatial patterns using a light modulator. The modulated light stream is sensed with a light sensor to obtain a time sequence (stream) of measurements. Overlapping subsets of the measurements are generated at a rate that equals a desired image rate. Each of the subsets is processed to algorithmically reconstruct a corresponding image, preferably with bounded latency. The resulting images are displayed at the desired image rate. The modulation, sensing, subset generation, reconstruction and display may be arranged as a continuous pipeline process. Different images rates may be achieved by changing the amount of overlap between the subsets.

A system and method for conserving power in compressive imaging. An optical subsystem separates an incident light stream into a primary light stream and a secondary light stream. The primary light stream is modulated with a sequence of spatial patterns by a light modulator. The modulated light stream is sensed by a first light sensing device. The secondary light stream is sensed by a second light sensing device. The signal(s) produced by the second light sensing device may be monitored to determine when to turn on power to the light modulator. Thus, the light modulator may remain off when not needed. In an alternative implementation, a light sensing device is used to sense the light reflected from the light modulator in its power-off state. The signal(s) produced by that light sensing device may be monitored to determine when to turn on power to the light modulator.

A method for estimating an optical, electromagnetic or acoustic image having at least the successive steps of: scattering an incident optical, electromagnetic or acoustic signal using a multiple scattering medium corresponding to a known transmission matrix stored into a memory of an imaging system; measuring the scattered signal using a detector array and storing the measurements into the memory of the imaging system; and determining an estimated image having a number of image elements that is greater than the number of measurements, at full spatial bandwidth. The estimated image is determined from the measurements and the transmission matrix using a sparsity-promoting algorithm.

An exemplary lensless compressive imaging device may include a micro mirror array having a plurality of mirror elements that are individually controllable for selectively directing light reflecting from the micro mirror array. A detector detects light reflected from at least one of the mirror elements. A processor provides compressive image information based on the detected light.

A method for compressing imaging data includes acquiring a stream of imaging data, and dividing the stream of imaging data into a plurality of interstices, each interstice including a plurality of detected events. The also includes classifying the detected events within each interstice based on a probability of occurrence of the detected event, and reordering the detected events within each interstice based on the probability of occurrence to compress the image data. The method further includes generating a ring pair identification number for each detected event in the plurality of interstices.

The invention discloses a hyper-spectral compressive imaging method based on three-dimensional tensor compressed sensing, and the method is mainly used for solving the problem that the structural information of multidimensional data in a multi-dimensional compressed sensing process is broken in prior art. The implementation steps of the method are as follows: simultaneously performing compressed sampling on three dimensionalities of a hyper-spectral image on the basis of not vectoring the hyper-spectral image via introducing a tensor method to obtain a measuring value; then calculating sensing matrixes on the three dimensionalities; then using a tensor orthogonal matching pursuit algorithm to calculate a sparse coefficient; finally finishing reconstitution of the hyper-spectral image according to a multi-dimensional sparse representation of the hyper-spectral image. The experimental result shows that the hyper-spectral compressive imaging method based on three-dimensional tensor compressed sensing of the invention is fast in reconstitution speed and good in effect in comparison with other traditional compressed sensing methods in same sampling rate, and could be used for obtaining a remote sensing image.

A method and apparatus for new digital image / video camera that directly acquires random projections of the incident light field without first collecting the pixels / voxels and has a startle reflex. The startle reflex is achieved by collecting a training set of samples while operating the imaging device at the low sampling rate, computing an empirical probability distribution of the training set of samples, collecting a testing set of samples while operating the imaging device at the low sampling rate, computing an empirical probability distribution of the testing set of samples, computing an empirical entropy test statistic, and capturing an image at the high sampling rate in response to the computed empirical entropy statistic exceeding a threshold.

Described is a knowledge-enhanced compressive imaging system. The system first initializes a compressive measurement basis set and a measurement matrix using task- and scene-specific prior knowledge. An image captured using the imaging mode of the dual-mode sensor is then sampled to extract context knowledge. The compressive measurement basis set and the measurement matrix are adapted using the extracted context knowledge and the prior knowledge. Task-relevant compressive measurements of the image are performed using the compressive measurement mode of the dual-mode sensor, and compressive reconstruction of the image is performed. Finally, a task and context optimized signal representation of the image is generated.

A method, non-transitory computer readable medium, and apparatus for compressive imaging of a scene in a single pixel camera are disclosed. For example, the method moves a pseudo-random pattern media behind an aperture until a pseudo-random sampling function of a plurality of pseudo-random sampling functions is viewable through the aperture, records a value of an intensity of a modulated light from the scene with a detector, wherein the intensity of the modulated light is representative of an inner product between the pseudo-random sampling function and an image of the scene and repeats the moving and the recording until a necessary number of a plurality of inner products are processed.

A compressive imaging system including a light modulator, a light sensing device and a TIR prism. The TIR prism is configured to receive an incident light beam, to provide the incident light beam to the light modulator, to receive a modulated light beam MLB from the light modulator, and to direct the modulated light beam onto a sensing path. The light sensing device receives the modulated light beam (or at least a portion of the modulated light beam) and generates an electrical signal that represents intensity of the modulated light beam (or the “at least a portion” of the modulated light beam). The TIR prism may reduce a distance required to separate the incident light beam from the modulated light beam.

The invention provides a parallel time-space domain joint compression imaging method and device adopting a DMD. A space domain compression imaging technology and a time domain compression imaging technology are combined, a digital micromirror device DMD is utilized to carry out time domain modulation on target light information while space domain modulation is carried out, and a detector only needs to receive a low-speed low-resolution image subjected to time domain and space domain modulation; finally, the original high-speed high-resolution image is recovered from the modulated image by using a recovery algorithm. According to the method, the spatial resolution and the temporal resolution of the camera can be expanded at the same time, and an image sequence with higher temporal resolution and spatial resolution can be obtained on the premise of not changing the camera. Meanwhile, time-space domain compression imaging has a very high compression ratio, so that the acquired data volumecan be remarkably reduced, the requirement of a high-speed high-resolution video on the transmission bandwidth is reduced, and a high-speed high-resolution imaging system is lower in cost and easierto realize.

An imaging system and method that captures compressive sensing (CS) measurements of a received light stream, and also obtains samples of background light level (BGLL). The BGLL samples may be used to compensate the CS measurements for variations in the BGLL. The system includes: a light modulator to spatially modulate the received light stream with spatial patterns, and a lens to concentrate the modulated light stream onto a light detector. The samples of BGLL may be obtained in various ways: (a) injecting calibration patterns among the spatial patterns; (b) measuring complementary light reflected by digital micromirrors onto a secondary output path; (c) separating and measuring a portion of light from the optical input path; (d) low-pass filtering the CS measurements; and (e) employing a light power meter with its own separate input path. Also, the CS measurements may be high-pass filtered to attenuate background light variation.

The present disclosure provides systems and methods that are configured for feature extraction or object recognition using compressive measurements that represent a compressed image of a scene. In various aspects, a compressive sensing matrix is constructed and used to acquire the compressive measurements, such that in the extraction phase, the compressive measurements can be processed to detect feature points and determine their feature vectors in the scene without using a pixel representation of the scene. The determined feature vectors are used to detect objects based on comparison with one or more predetermined feature vectors.