English
Related papers

Related papers: Synthesis imaging with a lunar orbit array: I. glo…

200 papers

X-ray ptychography is one of the versatile techniques for nanometer resolution imaging. The magnitude of the diffraction patterns is recorded on a detector and the phase of the diffraction patterns is estimated using phase retrieval…

Image and Video Processing · Electrical Eng. & Systems 2021-05-21 Prasan Shedligeri , Florian Schiffers , Semih Barutcu , Pablo Ruiz , Aggelos K Katsaggelos , Oliver Cossairt

Using light spectra is an essential element in many applications, for example, in material classification. Often this information is acquired by using a hyperspectral camera. Unfortunately, these cameras have some major disadvantages like…

Image and Video Processing · Electrical Eng. & Systems 2022-09-19 Frank Sippel , Jürgen Seiler , André Kaup

State of the art methods in astronomical image reconstruction rely on the resolution of a regularized or constrained optimization problem. Solving this problem can be computationally intensive and usually leads to a quadratic or at least…

Computer Vision and Pattern Recognition · Computer Science 2017-06-08 Rémi Flamary

In many image processing tasks it occurs that pixels or blocks of pixels are missing or lost in only some channels. For example during defective transmissions of RGB images, it may happen that one or more blocks in one color channel are…

Image and Video Processing · Electrical Eng. & Systems 2022-09-19 Frank Sippel , Jürgen Seiler , André Kaup

Image restoration is a technique that reconstructs a feasible estimate of the original image from the noisy observation. In this paper, we present a U-Net based deep neural network model to restore the missing pixels on the lunar surface…

Computer Vision and Pattern Recognition · Computer Science 2019-04-16 Hiya Roy , Subhajit Chaudhury , Toshihiko Yamasaki , Danielle DeLatte , Makiko Ohtake , Tatsuaki Hashimoto

This paper presents an uncalibrated deep neural network framework for the photometric stereo problem. For training models to solve the problem, existing neural network-based methods either require exact light directions or ground-truth…

Computer Vision and Pattern Recognition · Computer Science 2021-04-20 Berk Kaya , Suryansh Kumar , Carlos Oliveira , Vittorio Ferrari , Luc Van Gool

Radio interferometry allows astronomers to probe small spatial scales that are often inaccessible with single-dish instruments. However, recovering the radio sky from an interferometer is an ill-posed deconvolution problem that astronomers…

Instrumentation and Methods for Astrophysics · Physics 2022-05-25 Liam Connor , Katherine L. Bouman , Vikram Ravi , Gregg Hallinan

Line spectral estimation is the problem of recovering the frequencies and amplitudes of a mixture of a few sinusoids from equispaced samples. However, in a variety of signal processing problems arising in imaging, radar, and localization we…

Information Theory · Computer Science 2016-09-28 Reinhard Heckel , Mahdi Soltanolkotabi

3D reconstruction of a scene from Synthetic Aperture Radar (SAR) images mainly relies on interferometric measurements, which involve strict constraints on the acquisition process. These last years, progress in deep learning has…

Computer Vision and Pattern Recognition · Computer Science 2025-02-18 Emile Barbier--Renard , Florence Tupin , Nicolas Trouvé , Loïc Denis

We introduce an algorithm for the deconvolution of radio synthesis images that accounts for the non-coplanar-baseline effect, allows multiscale reconstruction onto arbitrarily positioned pixel grids, and allows the antenna elements to have…

Instrumentation and Methods for Astrophysics · Physics 2013-10-09 Stephen J. Hardy

The 21-cm global signal is obscured by very bright galactic and extra galactic foreground emissions. Typical single-spectrum fit (SSF) based methods for foreground/signal separation can result in biased estimates of the cosmological signal…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-27 Yordan D. Ignatov , Jonathan R. Pritchard

An unbiased method for improving the resolution of astronomical images is presented. The strategy at the core of this method is to establish a linear transformation between the recorded image and an improved image at some desirable…

Astrophysics · Physics 2016-08-30 F. P. Pijpers

In the era of big data, radio astronomical image reconstruction algorithms are challenged to estimate clean images given limited computing resources and time. This article is driven by the need for large scale image reconstruction for the…

Instrumentation and Methods for Astrophysics · Physics 2019-08-20 Rita Ammanouil , André Ferrari , David Mary , Chiara Ferrari , Francesca Loi

Aperture synthesis techniques are increasingly being employed to provide high angular resolution images in situations where the object of interest is in the near field of the interferometric array. Previous work has showed that an aperture…

Instrumentation and Methods for Astrophysics · Physics 2023-07-19 David F. Buscher

This paper is the first in a series devoted to the hard X-ray whole sky survey performed by the INTEGRAL observatory over seven years. Here we present an improved method for image reconstruction with the IBIS coded mask telescope. The main…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 R. Krivonos , M. Revnivtsev , S. Tsygankov , S. Sazonov , A. Vikhlinin , M. Pavlinsky , E. Churazov , R. Sunyaev

Radio astronomical imaging using aperture synthesis telescopes requires deconvolution of the point spread function as well as calibration of the instrumental characteristics (primary beam) and foreground (ionospheric/atmospheric) effects.…

Instrumentation and Methods for Astrophysics · Physics 2011-11-24 Juan M. Uson , William D. Cotton

Reflection seismic imaging usually suffers from a loss of resolution and contrast because of the fluctuations of the wave velocities in the Earth's crust. In the literature, phase distortion issues are generally circumvented by means of a…

Geophysics · Physics 2021-05-13 Rita Touma , Thibaud Blondel , Arnaud Derode , Michel Campillo , Alexandre Aubry

This article is written to serve as an introduction and survey of imaging with synthetic aperture radar (SAR). The reader will benefit from having some familiarity with harmonic analysis, electromagnetic radiation, and inverse problems.…

Numerical Analysis · Mathematics 2019-10-24 Toby Sanders , Christian Dwyer , Rodrigo B. Platte

Hyperspectral images contain mixed pixels due to low spatial resolution of hyperspectral sensors. Spectral unmixing problem refers to decomposing mixed pixels into a set of endmembers and abundance fractions. Due to nonnegativity constraint…

Computer Vision and Pattern Recognition · Computer Science 2014-08-13 Roozbeh Rajabi , Hassan Ghassemian

Obtaining a faithful source intensity distribution map of the sky from noisy data demands incorporating known information of the expected signal, especially when the signal is weak compared to the noise. We introduce a widely used procedure…

General Relativity and Quantum Cosmology · Physics 2019-09-04 Sambit Panda , Swetha Bhagwat , Jishnu Suresh , Sanjit Mitra
‹ Prev 1 3 4 5 6 7 10 Next ›