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Related papers: Deconvolution with Shapelets

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Denoising of coefficients in a sparse domain (e.g. wavelet) has been researched extensively because of its simplicity and effectiveness. Literature mainly has focused on designing the best global threshold. However, this paper proposes a…

Image and Video Processing · Electrical Eng. & Systems 2018-01-03 Hamid Reza Shahdoosti

Image denoising has become an essential exercise in medical imaging especially the Magnetic Resonance Imaging (MRI). This paper proposes a medical image denoising algorithm using contourlet transform. Numerical results show that the…

Other Computer Science · Computer Science 2011-03-28 S. Satheesh , KVSVR Prasad

The details of an image with noise may be restored by removing noise through a suitable image de-noising method. In this research, a new method of image de-noising based on using median filter (MF) in the wavelet domain is proposed and…

Multimedia · Computer Science 2017-03-21 Afrah Ramadhan , Firas Mahmood , Atilla Elci

Today, image denoising by thresholding of wavelet coefficients is a commonly used tool for 2D image enhancement. Since the data product of spectroscopic imaging surveys has two spatial and one spectral dimension, the techniques for…

Instrumentation and Methods for Astrophysics · Physics 2015-06-03 Lars Flöer , Benjamin Winkel

We present the optimal convergence and shear estimators for lensing reconstruction from the cosmic microwave background temperature field. This generalizes the deflection estimator, is sensitive to non-lensing modes, provides internal…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-18 Hong-Ming Zhu , Ue-Li Pen

We present our results from training and evaluating a convolutional neural network (CNN) to predict galaxy shapes from wide-field survey images of the first data release of the Dark Energy Survey (DES DR1). We use conventional shape…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-25 Dezső Ribli , László Dobos , István Csabai

Statistics of the weak lensing of galaxies can be used to constrain cosmology if the galaxy shear can be estimated accurately. In general this requires accurate modelling of unlensed galaxy shapes and the point spread function (PSF). I…

Astrophysics of Galaxies · Physics 2009-09-07 Antony Lewis

We derive expressions, in terms of "polar shapelets", for the image distortion operations associated with weak gravitational lensing. Shear causes galaxy shapes to become elongated, and is sensitive to the second derivative of the projected…

Astrophysics · Physics 2008-11-26 Richard Massey , Barnaby Rowe , Alexandre Refregier , David J. Bacon , Joel Berge

Deconvolution is the important problem of estimating the distribution of a quantity of interest from a sample with additive measurement error. Nearly all methods in the literature are based on Fourier transformation because it is…

Methodology · Statistics 2026-03-03 Yun Cai , Hong Gu , Toby Kenney

We have developed a regularisation procedure for the direct deprojection and PSF-deconvolution of X-ray surface brightness profiles of clusters of galaxies. This procedure allows us to obtain accurate density profiles in a straightforward…

Astrophysics · Physics 2009-11-11 J. H. Croston , M. Arnaud , E. Pointecouteau , G. W. Pratt

We reinterpret the shear estimator developed by Zhang & Komatsu (2011) within the framework of Shapelets and propose the Fourier Power Function Shapelets (FPFS) shear estimator. Four shapelet modes are calculated from the power function of…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-12 Xiangchong Li , Nobuhiko Katayama , Masamune Oguri , Surhud More

Galaxy model subtraction removes the smooth light of nearby galaxies so that fainter sources (e.g., stars, star clusters, background galaxies) can be identified and measured. Traditional approaches (isophotal or parametric fitting) are…

Instrumentation and Methods for Astrophysics · Physics 2025-10-07 Rongrong Liu , Eric W. Peng , Kaixiang Wang , Laura Ferrarese , Patrick Côté

We propose the application of multiresolution transforms, such as wavelets (WT) and curvelets (CT), to the reconstruction of images of extended objects that have been acquired with adaptive optics (AO) systems. Such multichannel approaches…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Roberto Baena Gallé , Jorge Núñez , Szymon Gladysz

We provide a new algorithm for the treatment of the deconvolution problem on the sphere which combines the traditional SVD inversion with an appropriate thresholding technique in a well chosen new basis. We establish upper bounds for the…

Statistics Theory · Mathematics 2016-08-14 Gérard Kerkyacharian , Thanh Mai Pham Ngoc , Dominique Picard

Images of near-field SAR contains spatial-variant sidelobes and clutter, subduing the image quality. Current image restoration methods are only suitable for small observation angle, due to their assumption of 2D spatial-invariant…

Signal Processing · Electrical Eng. & Systems 2022-10-06 Wensi Zhang , Xiaoling Zhang , Xu Zhan , Yuetonghui Xu , Jun Shi , Shunjun Wei

Magnetic Particle Imaging (MPI) is an emerging imaging modality that maps the spatial distribution of magnetic nanoparticles. The x-space reconstruction in MPI results in highly blurry images, where the resolution depends on both system…

Medical Physics · Physics 2020-01-31 Onur Yorulmaz , Omer Burak Demirel , Yavuz Muslu , Tolga Çukur , Emine U Saritas , A Enis Çetin

Metacalibration is a new technique for measuring weak gravitational lensing shear that is unbiased for isolated galaxy images. In this work we test metacalibration with overlapping, or ``blended'' galaxy images. Using standard…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-28 Erin S. Sheldon , Matthew R. Becker , Niall MacCrann , Michael Jarvis

We present a performance test of the Point Spread Function deconvolution algorithm applied to astronomical Integral Field Unit (IFU) Spectroscopy data for restoration of galaxy kinematics. We deconvolve the IFU data by applying the…

Astrophysics of Galaxies · Physics 2021-12-22 Haeun Chung , Changbom Park , Yong-Sun Park

I present a method for the fast convolution of a model galaxy profile by a point-spread function (PSF) model represented as a pixel grid. The method relies upon three observations: First, most simple radial galaxy profiles of common…

Instrumentation and Methods for Astrophysics · Physics 2021-01-01 Dustin Lang

Strong gravitational lensing is regarded as the most precise technique to measure the mass in the inner region of galaxies or galaxy clusters. In particular, the mass within one Einstein radius can be determined with an accuracy of order of…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-10 Sandra Unruh , Peter Schneider , Dominique Sluse
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