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Related papers: Fast & Furious focal-plane wavefront sensing

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In this paper, we develop a modified differential Structure from Motion (SfM) algorithm that can estimate relative pose from two consecutive frames despite of Rolling Shutter (RS) artifacts. In particular, we show that under constant…

Computer Vision and Pattern Recognition · Computer Science 2019-08-06 Bingbing Zhuang , Loong-Fah Cheong , Gim Hee Lee

Many interesting and fundamentally practical optimization problems, ranging from optics, to signal processing, to radar and acoustics, involve constraints on the Fourier transform of a function. It is well-known that the {\em fast Fourier…

Optimization and Control · Mathematics 2012-09-05 Robert J. Vanderbei

Fourier ptychographi cmicroscopy(FPM) is a newly developed computational imaging technique that can provide gigapixel images with both high resolution (HR) and wide field of view (FOV). However, the positional misalignment of the LED array…

Computer Vision and Pattern Recognition · Computer Science 2018-09-03 Ao Zhou , Wei Wang , Ni Chen , Edmund Y. Lam , Byoungho Lee , Guohai Situ

The technique requires the epipolar geometry to be pre-estimated between each image pair. It exploits the constraints which the camera movement implies, in order to apply a closed-form correction to the parameters of the input affinities.…

Computer Vision and Pattern Recognition · Computer Science 2019-05-03 Ivan Eichhardt , Daniel Barath

Resolving sources beyond the diffraction limit is important in imaging, communications, and metrology. Current image-based methods of super-resolution require phase information (either of the source points or an added filter) and perfect…

Optics · Physics 2025-12-16 S. A. Wadood , Shaurya Aarav , Kevin Liang , Jason W Fleischer

X-ray phase-contrast imaging has the potential to improve image contrast with lower dose by probing an object's refractive properties as well as its absorptive properties. To reconstruct a phase-contrast image from a raw dataset, a phase…

Medical Physics · Physics 2025-08-19 Giavanna Jadick , Patrick La Rivière

One of the major difficulties limiting ground-based direct imaging of exoplanets with adaptive optics is quasi-static speckles in the science camera (SC) that obscure the planetary image. These speckles are caused by aberrations, called…

Instrumentation and Methods for Astrophysics · Physics 2018-11-14 Richard A. Frazin

For beamforming ultrasound (US) signals, typically a spatially constant speed-of-sound (SoS) is assumed to calculate delays. As SoS in tissue may vary relatively largely, this approximation may cause wavefront aberrations, thus degrading…

Image and Video Processing · Electrical Eng. & Systems 2019-12-12 Richard Rau , Dieter Schweizer , Valery Vishnevskiy , Orcun Goksel

We use telemetry data from the Gemini North ALTAIR adaptive optics system to investigate how well the commands for wavefront correction (both Tip/Tilt and high-order turbulence) can be forecasted in order to reduce lag error (due to…

Instrumentation and Methods for Astrophysics · Physics 2022-05-16 Rehan Hafeez , Finn Archinuk , Sébastien Fabbro , Hossen Teimoorinia , Jean-Pierre Véran

Space-based coronagraphs for future earth-like planet detection will require focal plane wavefront control techniques to achieve the necessary contrast levels. These correction algorithms are iterative and the control methods require an…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Tyler D. Groff , N. Jeremy Kasdin

Point Spread Function (PSF) engineering is used in single emitter localization to measure the emitter position in 3D and possibly other parameters such as the emission color or dipole orientation as well. Advanced PSF models such as spline…

Weak gravitational lensing observations are a key science driver for the NASA Wide Field Infrared Survey Telescope (WFIRST). To validate the performance of the WFIRST infrared detectors, we have performed a laboratory emulation of weak…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 Suresh Seshadri , Charles Shapiro , Timothy Goodsall , Jason Fucik , Christopher M. Hirata , Jason Rhodes , Barnaby Rowe , Roger Smith

The integral image, an intermediate image representation, has found extensive use in multi-scale local feature detection algorithms, such as Speeded-Up Robust Features (SURF), allowing fast computation of rectangular features at constant…

Computer Vision and Pattern Recognition · Computer Science 2015-10-20 Shoaib Ehsan , Adrian F. Clark , Naveed ur Rehman , Klaus D. McDonald-Maier

This paper presents a fast and principled approach for solving the visual anomaly detection and segmentation problem. In this setup, we have access to only anomaly-free training data and want to detect and identify anomalies of an arbitrary…

Computer Vision and Pattern Recognition · Computer Science 2022-11-24 Ibrahima Ndiour , Nilesh Ahuja , Utku Genc , Omesh Tickoo

Accurately simulating the atmospheric turbulence behaviour is always challenging. The well-known FFT based method falls short in correctly predicting both the low and high frequency behaviours. Sub-harmonic compensation aids in…

Instrumentation and Methods for Astrophysics · Physics 2022-08-15 Sorabh Chhabra , Jyotirmay Paul , A. N. Ramaprakash , Avinash Surendran

Retrieving object phase from the optical fringe pattern is a critical task in quantitative phase imaging and often requires appropriate image preprocessing (background and noise minimization), especially when retrieving phase from the…

Wide field-of-view (FOV) cameras, which capture a larger scene area than narrow FOV cameras, are used in many applications including 3D reconstruction, autonomous driving, and video surveillance. However, wide-angle images contain…

Computer Vision and Pattern Recognition · Computer Science 2021-12-02 Jinlong Fan , Jing Zhang , Stephen J. Maybank , Dacheng Tao

This work presents an algorithmic scheme for solving the infinite-time constrained linear quadratic regulation problem. We employ an accelerated version of a popular proximal gradient scheme, commonly known as the Forward-Backward Splitting…

Optimization and Control · Mathematics 2015-01-20 Giorgos Stathopoulos , Milan Korda , Colin N. Jones

We report a novel generalized optical measurement system and computational approach to determine and correct aberrations in optical systems. We developed a computational imaging method capable of reconstructing an optical system's…

Image and Video Processing · Electrical Eng. & Systems 2019-01-10 Jaebum Chung , Gloria W. Martinez , Karen Lencioni , Srinivas Sadda , Changhuei Yang

We demonstrate a wavefront sensor based on the compressive sensing, single-pixel camera. Using a high-resolution spatial light modulator (SLM) as a variable waveplate, we weakly couple an optical field's transverse-position and polarization…

Optics · Physics 2014-07-30 Gregory A. Howland , Daniel J. Lum , John C. Howell