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High-contrast imaging instruments need extreme wavefront control to directly image exoplanets. This requires highly sensitive wavefront sensors which optimally make use of the available photons to sense the wavefront. Here, we propose to…

Instrumentation and Methods for Astrophysics · Physics 2022-09-14 Rico Landman , Christoph Keller , Emiel H. Por , Sebastiaan Haffert , David Doelman , Thijs Stockmans

Interferometric phase (InPhase) imaging is an important part of many present-day coherent imaging technologies. Often in such imaging techniques, the acquired images, known as interferograms, suffer from two major degradations: 1) phase…

Signal Processing · Electrical Eng. & Systems 2019-11-25 Joshin P. Krishnan , Mário A. T. Figueiredo , José M. Bioucas-Dias

We propose using the Wasserstein loss for training in inverse problems. In particular, we consider a learned primal-dual reconstruction scheme for ill-posed inverse problems using the Wasserstein distance as loss function in the learning.…

Computer Vision and Pattern Recognition · Computer Science 2017-10-31 Jonas Adler , Axel Ringh , Ozan Öktem , Johan Karlsson

Neglecting the second order corrections in weak lensing measurements can lead to a few percent uncertainties on cosmic shears, and becomes more important for cluster lensing mass reconstructions. Existing methods which claim to measure the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Jun Zhang

Direct reconstruction through filtered back projection engenders metal artifacts in polychromatic computed tomography images, attributed to highly attenuating implants, which further poses great challenges for subsequent image analysis.…

Optimization and Control · Mathematics 2024-02-05 Lianfang Wang , Zhangling Chen , Zhifang Liu , Yutong Li , Yunsong Zhao , Hongwei Li , Huibin Chang

An extension may be proposed to the intensity interferometer of Hanbury Brown and Twiss to provide the Fourier phase measurement by the use of third-order intensity correlations. It is well known that interferometric reconstruction of…

Astrophysics · Physics 2008-06-14 B. E. Zhilyaev

Modern-day seismic imaging and monitoring technology increasingly rely on dense full-azimuth sampling. Unfortunately, the costs of acquiring densely sampled data rapidly become prohibitive and we need to look for ways to sparsely collect…

Optimization and Control · Mathematics 2020-04-22 Yijun Zhang , Shashin Sharan , Oscar Lopez , Felix J. Herrmann

Shuffled linear regression (SLR) seeks to estimate latent features through a linear transformation, complicated by unknown permutations in the measurement dimensions. This problem extends traditional least-squares (LS) and Least Absolute…

Statistics Theory · Mathematics 2025-04-17 Hang Liu , Anna Scaglione

Wavefront sensing involves estimating the phase and intensity of light, enabling a wide range of imaging applications, from adaptive optics and astronomy to biomedical imaging. Since conventional image sensors can only measure the spatial…

Image and Video Processing · Electrical Eng. & Systems 2026-04-07 Nebiyou Yismaw , Vishwanath Saragadam , Aswin C. Sankaranarayanan , M. Salman Asif

We develop a novel wave imaging scheme for reconstructing the shape of an inhomogeneous scatterer and we consider the inverse acoustic obstacle scattering problem as a prototype model for our study. There exists a wealth of reconstruction…

Analysis of PDEs · Mathematics 2020-01-08 Hongyu Liu , Xiaodong Liu , Xianchao Wang , Yuliang Wang

Experimentalists often use wind tunnels to study aerodynamic turbulence, but most wind tunnel imaging techniques are limited in their ability to take non-invasive 3D density measurements of turbulence. Wavefront tomography is a technique…

Signal Processing · Electrical Eng. & Systems 2026-02-19 Karl J. Weisenburger , Gregery T. Buzzard , Charles A. Bouman , Matthew R. Kemnetz

W projection is a commonly-used approach to allow interferometric imaging to be accelerated by Fast Fourier Transforms (FFTs), but it can require a huge amount of storage for convolution kernels. The kernels are not separable, but we show…

Instrumentation and Methods for Astrophysics · Physics 2016-01-27 Bruce Merry

Three-dimensional x-ray CT image reconstruction in baggage scanning in security applications is an important research field. The variety of materials to be reconstructed is broader than medical x-ray imaging. Presence of high attenuating…

Computer Vision and Pattern Recognition · Computer Science 2015-08-20 S. Degirmenci , Joseph A. O'Sullivan , David G. Politte

Total variation regularization based on the l1 norm is ubiquitous in image reconstruction. However, the resulting reconstructions are not always as sparse in the edge domain as desired. Iteratively reweighted methods provide some…

Image and Video Processing · Electrical Eng. & Systems 2022-04-01 Victor Churchill , Rick Archibald , Anne Gelb

This paper presents an iterative inversion algorithm for computed tomography image reconstruction that performs well in terms of accuracy and speed using limited data. The computational method combines an image domain technique and…

Image and Video Processing · Electrical Eng. & Systems 2019-01-17 Victor Churchill , Anne Gelb

Non-regular sampling can reduce aliasing at the expense of noise. Recently, it has been shown that non-regular sampling can be carried out using a conventional regular imaging sensor when the surface of its individual pixels is partially…

Image and Video Processing · Electrical Eng. & Systems 2022-03-02 Simon Grosche , Jürgen Seiler , André Kaup

As imaging surveys progress in exploring the large-scale structure of the Universe through the use of weak gravitational lensing, achieving subpercent accuracy in estimating shape distortions caused by lensing, or shear, is imperative for…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-22 Andy Park , Xiangchong Li , Rachel Mandelbaum

X-ray Bragg coherent diffraction imaging has been demonstrated as a powerful three-dimensional (3D) microscopy approach for the investigation of sub-micrometer-scale crystalline particles. It is based on the measurement of a series of…

We present a new shear estimator for weak lensing observations which properly accounts for the effects of a realistic point spread function (PSF). Images of faint galaxies are subject to gravitational shearing followed by smearing with the…

Astrophysics · Physics 2009-10-31 Nick Kaiser