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Related papers: Galaxy Image Restoration with Shape Constraint

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We study the impact of sampling theorems on the fidelity of sparse image reconstruction on the sphere. We discuss how a reduction in the number of samples required to represent all information content of a band-limited signal acts to…

Information Theory · Computer Science 2013-04-17 J. D. McEwen , G. Puy , J. -Ph. Thiran , P. Vandergheynst , D. Van De Ville , Y. Wiaux

We present a new approach to measure the shapes of galaxies, a fundamental task in observational astronomy. This approach is based on the decomposition of a galaxy image into a series of orthogonal basis functions, or `shapelets'. Our…

Astrophysics · Physics 2017-08-23 Alexandre Refregier , Tzu-Ching Chang , David Bacon

Precision weak gravitational lensing experiments require measurements of galaxy shapes accurate to <1 part in 1000. We investigate measurement biases, noted by Voigt and Bridle (2009) and Melchior et al. (2009), that are common to shape…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 Gary M. Bernstein

The wavelet frame systems have been playing an active role in image restoration and many other image processing fields over the past decades, owing to the good capability of sparsely approximating piece-wise smooth functions such as images.…

Computer Vision and Pattern Recognition · Computer Science 2016-03-29 Liangtian He , Yilun Wang , Zhaoyin Xiang

Nonlocal image representation or group sparsity has attracted considerable interest in various low-level vision tasks and has led to several state-of-the-art image denoising techniques, such as BM3D, LSSC. In the past, convex optimization…

Computer Vision and Pattern Recognition · Computer Science 2017-11-22 Qiong Wang , Xinggan Zhang , Yu Wu , Lan Tang , Zhiyuan Zha

Group sparse representation has shown promising results in image debulrring and image inpainting in GSR [3] , the main reason that lead to the success is by exploiting Sparsity and Nonlocal self-similarity (NSS) between patches on natural…

Computer Vision and Pattern Recognition · Computer Science 2022-12-23 Luoyu Chen , Fei Wu

Recovering corrupted images is one of the most challenging problems in image processing. Among various restoration tasks, blind image deblurring has been extensively studied due to its practical importance and inherent difficulty. In this…

Computer Vision and Pattern Recognition · Computer Science 2026-04-22 Heng Zhang , Reza Parvaz , Rui Yang

Sparse modeling is one of the efficient techniques for imaging that allows recovering lost information. In this paper, we present a novel iterative phase-retrieval algorithm using a sparse representation of the object amplitude and phase.…

Computer Vision and Pattern Recognition · Computer Science 2011-08-17 Artem Migukin , Vladimir Katkovnik , Jaakko Astola

A simple Gaussian size deconvolution method is routinely used to remove the blur of observed images caused by insufficient angular resolutions of existing telescopes, thereby to estimate the physical sizes of extracted sources and…

Instrumentation and Methods for Astrophysics · Physics 2023-07-26 Alexander Men'shchikov

Restoration of digital images from their degraded measurements has always been a problem of great theoretical and practical importance in numerous applications of imaging sciences. A specific solution to the problem of image restoration is…

Computer Vision and Pattern Recognition · Computer Science 2010-04-09 Elad Shaked , Oleg Michailovich

The intrinsic scatter in the ellipticities of galaxies about the mean shape, known as "shape noise," is the most important source of noise in weak lensing shear measurements. Several approaches to reducing shape noise have recently been put…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-21 Rupert A. C. Croft , Peter E. Freeman , Thomas S. Schuster , Chad M. Schafer

Patient scans from MRI often suffer from noise, which hampers the diagnostic capability of such images. As a method to mitigate such artifact, denoising is largely studied both within the medical imaging community and beyond the community…

Image and Video Processing · Electrical Eng. & Systems 2022-03-25 Hyungjin Chung , Eun Sun Lee , Jong Chul Ye

In this article, we present a denoising algorithm to improve the interpretation and quality of scanning tunneling microscopy (STM) images. Given the high level of self-similarity of STM images, we propose a denoising algorithm by…

Computer Vision and Pattern Recognition · Computer Science 2016-10-12 João P. Oliveira , Ana Bragança , José Bioucas-Dias , Mário Figueiredo , Luís Alcácer , Jorge Morgado , Quirina Ferreira

Image restoration in astronomy has been considered a vital step in many ground-based observational programs that often suffer from sub-optimal seeing due to atmospheric turbulence, distortion of stellar shapes due to instrumental…

Instrumentation and Methods for Astrophysics · Physics 2023-09-14 Yash Gondhalekar , Margarita Safonova , Snehanshu Saha

The measurement of weak gravitational lensing is currently limited to a precision of ~10% by instabilities in galaxy shape measurement techniques and uncertainties in their calibration. The potential of large, on-going and future cosmic…

Astrophysics · Physics 2009-11-10 Richard Massey , Alexandre Refregier , David Bacon

The problem of reconstruction of digital images from their degraded measurements is regarded as a problem of central importance in various fields of engineering and imaging sciences. In such cases, the degradation is typically caused by the…

Computer Vision and Pattern Recognition · Computer Science 2010-01-06 E. Shaked , O. Michailovich

Image denoising based on deep learning has witnessed significant advancements in recent years. However, existing deep learning methods lack quantitative control of the deviation or error on denoised images. The neural networks Self2Self is…

Instrumentation and Methods for Astrophysics · Physics 2025-02-25 Tie Liu , Yuhui Quan , Yingna Su , Yang Guo , Shu Liu , Haisheng Ji , Qi Hao , Yulong Gao , Yuxia Liu , Yikang Wang , Wenqing Sun , Mingde Ding

In this paper, we are interested in the classical problem of restoring data degraded by a convolution and the addition of a white Gaussian noise. The originality of the proposed approach is two-fold. Firstly, we formulate the restoration…

Methodology · Statistics 2015-05-13 Jean-Christophe Pesquet , Amel Benazza-Benyahia , Caroline Chaux

We describe a simple and fast method to correct ellipticity measurements of galaxies from the distortion by the instrumental and atmospheric point spread function (PSF), in view of weak lensing shear measurements. The method performs a…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-01 M. Tewes , N. Cantale , F. Courbin , T. D. Kitching , G. Meylan

Deconvolution with a box (square wave) is a key operation for super-resolution with pixel-shift cameras. In general convolution with a box is not invertible. However, we can obtain perfect reconstructions of sparse signals using convex…

Numerical Analysis · Mathematics 2024-07-17 Pedro Felzenszwalb