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Radio astronomy plays a crucial role in understanding the universe, particularly within the realm of non-thermal astrophysics. Images of celestial objects are derived from the signals (called visibility) measured by radio telescopes. Such…

Computer Vision and Pattern Recognition · Computer Science 2026-04-21 Kai Cheng , Ruoqi Wang , Qiong Luo

The joint problem of reconstruction / feature extraction is a challenging task in image processing. It consists in performing, in a joint manner, the restoration of an image and the extraction of its features. In this work, we firstly…

Computer Vision and Pattern Recognition · Computer Science 2024-03-06 Emilie Chouzenoux , Marie-Caroline Corbineau , Jean-Christophe Pesquet , Gabriele Scrivanti

Conventional Magnetic Resonance Imaging (MRI) is hampered by long scan times and only qualitative image contrasts that prohibit a direct comparison between different systems. To address these limitations, model-based reconstructions…

Image and Video Processing · Electrical Eng. & Systems 2022-10-24 Xiaoqing Wang , Zhengguo Tan , Nick Scholand , Volkert Roeloffs , Martin Uecker

We propose a supervised machine learning approach for boosting existing signal and image recovery methods and demonstrate its efficacy on example of image reconstruction in computed tomography. Our technique is based on a local nonlinear…

Computer Vision and Pattern Recognition · Computer Science 2013-12-02 Joseph Shtok , Michael Zibulevsky , Michael Elad

Galactic all-sky maps at very disparate frequencies, like in the radio and $\gamma$-ray regime, show similar morphological structures. This mutual information reflects the imprint of the various physical components of the interstellar…

Spectral image reconstruction is an important task in snapshot compressed imaging. This paper aims to propose a new end-to-end framework with iterative capabilities similar to a deep unfolding network to improve reconstruction accuracy,…

Image and Video Processing · Electrical Eng. & Systems 2023-05-09 Zeyu Cai , Jian Yu , Ziyu Zhang , Chengqian Jin , Feipeng Da

Despite its wide use in medicine, ultrasound imaging faces several challenges related to its poor signal-to-noise ratio and several sources of noise and artefacts. Enhancing ultrasound image quality involves balancing concurrent factors…

Computer Vision and Pattern Recognition · Computer Science 2024-10-28 Yuxin Zhang , Clément Huneau , Jérôme Idier , Diana Mateus

Recovering a signal from auto-correlations or, equivalently, retrieving the phase linked to a given Fourier modulus, is a wide-spread problem in imaging. This problem has been tackled in a number of experimental situations, from optical…

Image and Video Processing · Electrical Eng. & Systems 2021-02-03 Daniele Ancora , Andrea Bassi

A numerical scheme that uses multi-frequency Newton iterations to reconstruct a rough surface profile between two dielectric media is proposed. At each frequency sample, the scheme employs Newton iterations to solve the nonlinear inverse…

Numerical Analysis · Mathematics 2024-08-29 Ahmet Sefer , Ali Yapar , Hakan Bagci

We investigate the inverse source problem for the wave equation, arising in photo- and thermoacoustic tomography. There exist quite a few theoretically exact inversion formulas explicitly expressing solution of this problem in terms of the…

Analysis of PDEs · Mathematics 2018-08-01 Ngoc Do , Leonid Kunyansky

The iterative refinement method (IRM) has been very successfully applied in many different fields for examples the modern quantum chemical calculation and CT image reconstruction. It is proved that the refinement method can create an exact…

Medical Physics · Physics 2015-12-23 Kang Yang , Kevin Yang , Xintie Yang , Shuang-Ren Zhao

A new principle of subwavelength imaging based on frequency scanning is considered. It is shown that it is possible to reconstruct the spatial profile of an external field exciting an array (or coupled arrays) of subwavelength-sized…

Optics · Physics 2008-06-27 Stanislav Maslovski , Pekka Alitalo , Sergei Tretyakov

Hyperspectral neutron computed tomography is a tomographic imaging technique in which thousands of wavelength-specific neutron radiographs are measured for each tomographic view. In conventional hyperspectral reconstruction, data from each…

Currently, the engineering of miniature spectrometers mainly faces three problems: the mismatch between the number of filters at the front end of the detector and the spectral reconstruction accuracy; the lack of a stable spectral…

Data Analysis, Statistics and Probability · Physics 2022-09-19 Jiakun Zhang , Liu Zhang , Ying Song , Yan Zheng

We present a computational framework for efficient optimization-based "inverse design" of large-area "metasurfaces" (subwavelength-patterned surfaces) for applications such as multi-wavelength and multi-angle optimizations, and…

Purpose: Recent developments in hardware design enable the use of Fast Field-Cycling (FFC) techniques in MRI to exploit the different relaxation rates at very low field strength, achieving novel contrast. The method opens new avenues for in…

Signal Processing · Electrical Eng. & Systems 2021-05-19 Markus Bödenler , Oliver Maier , Rudolf Stollberger , Lionel M. Broche , P. James Ross , Mary-Joan MacLeod , Hermann Scharfetter

Radio-astronomical observations are increasingly contaminated by interference, and suppression techniques become essential. A powerful candidate for interference mitigation is adaptive spatial filtering. We study the effect of spatial…

Astrophysics · Physics 2014-10-13 Amir Leshem , Alle-Jan van der Veen

Image restoration aims to recover high-quality images from degraded observations. When the degradation process is known, the recovery problem can be formulated as an inverse problem, and in a Bayesian context, the goal is to sample a clean…

Image and Video Processing · Electrical Eng. & Systems 2025-10-13 Darshan Thaker , Abhishek Goyal , René Vidal

This paper develops a unifying framework for signal reconstruction from interferometric measurements that is broadly applicable to various applications of interferometry. In this framework, the problem of signal reconstruction in…

Information Theory · Computer Science 2017-07-03 Davood Mardani , George K. Atia , Ayman F. Abouraddy

Optical diffraction tomography relies on solving an inverse scattering problem governed by the wave equation. Classical reconstruction algorithms are based on linear approximations of the forward model (Born or Rytov), which limits their…

Computational Engineering, Finance, and Science · Computer Science 2017-09-01 Emmanuel Soubies , Thanh-An Pham , Michael Unser