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Related papers: Shapelets: I. A Method for Image Analysis

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The shapelets method for image analysis is based upon the decomposition of localised objects into a series of orthogonal components with convenient mathematical properties. We extend the "Cartesian shapelet" formalism from earlier work, and…

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

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

We introduce one- and two-dimensional `exponential shapelets': orthonormal basis functions that efficiently model isolated features in data. They are built from eigenfunctions of the quantum mechanical hydrogen atom, and inherit mathematics…

Instrumentation and Methods for Astrophysics · Physics 2019-03-27 Joel Bergé , Richard Massey , Quentin Baghi , Pierre Touboul

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

We present a method to simulate deep sky images, including realistic galaxy morphologies and telescope characteristics. To achieve a wide diversity of simulated galaxy morphologies, we first use the shapelets formalism to parametrize the…

We present a new approach for image reconstruction and weak lensing measurements with interferometers. Based on the shapelet formalism presented in Refregier (2001), object images are decomposed into orthonormal Hermite basis functions. The…

Astrophysics · Physics 2009-11-06 Tzu-Ching Chang , Alexandre Refregier

The decomposition of an image into a linear combination of digitised basis functions is an everyday task in astronomy. A general method is presented for performing such a decomposition optimally into an arbitrary set of digitised basis…

Astrophysics · Physics 2009-11-10 R. H. Berry , M. P. Hobson , S. Withington

A method for quantitative analysis of local pattern strength and defects in surface self-assembly imaging is presented and applied to images of stripe and hexagonal ordered domains. The presented method uses "shapelet" functions which were…

Computer Vision and Pattern Recognition · Computer Science 2015-02-27 Robert Suderman , Daniel Lizotte , Nasser Mohieddin Abukhdeir

Weak gravitational lensing provides a unique method to directly measure the distribution of mass in the universe. Because the distortions induced by lensing in the shape of background galaxies are small, the measurement of weak lensing…

Astrophysics · Physics 2009-11-06 Alexandre Refregier , David Bacon

Aims: We discuss the applicability and reliability of the shapelet technique for scientific image analysis. Methods: We quantify the effects of non-orthogonality of sampled shapelet basis functions and misestimation of shapelet parameters.…

Astrophysics · Physics 2009-11-11 P. Melchior , M. Meneghetti , M. Bartelmann

We present a method for characterizing image-subtracted objects based on shapelet analysis to identify transient events in ground-based time-domain surveys. We decompose the image-subtracted objects onto a set of discrete Zernike…

Instrumentation and Methods for Astrophysics · Physics 2019-10-17 Kendall Ackley , Stephen S. Eikenberry , Ceren Yildirim , Sergey Klimenko , Alan Garner

Accurate measurement of gravitational shear from images of distant galaxies is one of the most direct ways of studying the distribution of mass in the universe. We describe an implementation of a technique that is based on the shapelets…

Astrophysics · Physics 2009-11-11 Konrad Kuijken

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

We seek to find a shapelet-based scheme for deconvolving galaxy images from the PSF which leads to unbiased shear measurements. Based on the analytic formulation of convolution in shapelet space, we construct a procedure to recover the…

Astrophysics · Physics 2015-03-03 Peter Melchior , Rene Andrae , Matteo Maturi , Matthias Bartelmann

Wavelets are closely related to the Schr\"odinger's wave functions and the interpretation of Born. Similarly to the appearance of atomic orbital, it is proposed to combine anti-symmetric wavelets into orbital wavelets. The proposed approach…

Signal Processing · Electrical Eng. & Systems 2020-10-02 H. M. de Oliveira , V. V. Vermehren , R. J. Cintra

Lens modeling of resolved image data has advanced rapidly over the past two decades. More recently pixel-based approaches, wherein the source is reconstructed on an irregular or adaptive grid, have become popular. Generally, the source…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-09 Amitpal S. Tagore , Neal Jackson

With the increasing growth of technology and the entrance into the digital age, we have to handle a vast amount of information every time which often presents difficulties. So, the digital information must be stored and retrieved in an…

Multimedia · Computer Science 2012-08-15 Kamrul Hasan Talukder , Koichi Harada

The purpose is to study qualitative and quantitative rates of image compression by using different Haar wavelet banks. The experimental results of adaptive compression are provided. The paper deals with specific examples of orthogonal Haar…

Other Computer Science · Computer Science 2014-10-06 Mikhail Prisheltsev

Deep Learning (DL) has shown remarkable results in solving inverse problems in various domains. In particular, the Tikhonet approach is very powerful to deconvolve optical astronomical images (Sureau et al. 2020). Yet, this approach only…

Instrumentation and Methods for Astrophysics · Physics 2022-07-20 F. Nammour , U. Akhaury , J. N. Girard , F. Lanusse , F. Sureau , C. Ben Ali , J. -L. Starck

Strong gravitational lensing provides a wealth of astrophysical information on the baryonic and dark matter content of galaxies. It also serves as a valuable cosmological probe by allowing us to measure the Hubble constant independently of…

Astrophysics of Galaxies · Physics 2021-03-31 A. Galan , A. Peel , R. Joseph , F. Courbin , J. -L. Starck
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