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Related papers: Wavelets, ridgelets and curvelets on the sphere

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We construct non-trivial continuous isospectral deformations of Riemannian metrics on the ball and on the sphere in $\R^n$ for every $n\geq 9$. The metrics on the sphere can be chosen arbitrarily close to the round metric; in particular,…

Differential Geometry · Mathematics 2009-10-31 Carolyn S. Gordon

The representation of discrete, compact wavelet transformations (WTs) as circuits of local unitary gates is discussed. We employ a similar formalism as used in the multi-scale representation of quantum many-body wavefunctions using unitary…

Quantum Physics · Physics 2018-05-14 Glen Evenbly , Steven R. White

Radially symmetric wavelets possessing multiresolution framework are found to be useful in different fields like Pattern recognition, Computed Tomography (CT) etc. The compactly supported wavelets are known to be useful for localized…

Functional Analysis · Mathematics 2020-09-14 K. Z. Najiya , Akshaya Ravichandran , C. S. Sastry

We present a new and general framework for convolutional neural network operations on spherical (or omnidirectional) images. Our approach represents the surface as a graph of connected points that doesn't rely on a particular sampling…

Computer Vision and Pattern Recognition · Computer Science 2022-10-20 David Hart , Michael Whitney , Bryan Morse

Deep image registration has demonstrated exceptional accuracy and fast inference. Recent advances have adopted either multiple cascades or pyramid architectures to estimate dense deformation fields in a coarse-to-fine manner. However, due…

Computer Vision and Pattern Recognition · Computer Science 2024-07-19 Xinxing Cheng , Xi Jia , Wenqi Lu , Qiufu Li , Linlin Shen , Alexander Krull , Jinming Duan

Modeling deformations of a real object is an important task in computer vision, biomedical engineering and biomechanics. In this paper, we focus on a situation where a three-dimensional object is rotationally deformed about a fixed axis,…

Statistics Theory · Mathematics 2016-06-14 Sungkyu Jung

Wavelet theory has been well studied in recent decades. Due to their appealing features such as sparse multiscale representation and fast algorithms, wavelets have enjoyed many tremendous successes in the areas of signal/image processing…

Numerical Analysis · Mathematics 2019-09-27 Bin Han , Michelle Michelle , Yau Shu Wong

New variables of separation for few integrable systems on the two-dimensional sphere with higher order integrals of motion are considered in detail. We explicitly describe canonical transformations of initial physical variables to the…

Exactly Solvable and Integrable Systems · Physics 2015-05-30 A. V. Tsiganov , V. A. Khudobakhshov

The Easy Path Wavelet Transform is an adaptive transform for bivariate functions (in particular natural images) which has been proposed in [1]. It provides a sparse representation by finding a path in the domain of the function leveraging…

Information Theory · Computer Science 2017-02-16 Renato Budinich

In this article, we develop a general method for constructing wavelets {|det A_j|^{1/2} g(A_jx-x_{j,k}): j in J, k in K}, on irregular lattices of the form X={x_{j,k} in R^d: j in J, k in K}, and with an arbitrary countable family of…

Classical Analysis and ODEs · Mathematics 2007-05-23 Akram Aldroubi , Carlos Cabrelli , Ursula M. Molter

In this paper we establish a multiscale approximation for random fields on the sphere using spherical needlets --- a class of spherical wavelets. We prove that the semidiscrete needlet decomposition converges in mean and pointwise senses…

Numerical Analysis · Mathematics 2016-12-13 Quoc T. Le Gia , Ian H. Sloan , Yu Guang Wang , Robert S. Womerlsey

The use of orthonormal wavelet basis functions for solving singular integral scattering equations is investigated. It is shown that these basis functions lead to sparse matrix equations which can be solved by iterative techniques. The…

Nuclear Theory · Physics 2009-11-10 B. M. Kessler , G. L. Payne , W. N. Polyzou

The symplectic wavelet transformation [Opt. Lett. 31 (2006) 3432], which is related to quantum optical Fresnel transform, is developed to the symplectic-dilation mixed wavelet transform (SDWT). The SDWT involves both a real-variable…

Quantum Physics · Physics 2009-11-13 Hong-yi Fan , Shu-guang Liu , Li-yun Hu

Many known Radon-type transforms of symmetric (radial or zonal) functions are represented by one-dimensional Riemann-Liouville fractional integrals or their modifications. The present article contains new examples of such transforms in the…

Functional Analysis · Mathematics 2024-12-31 Boris Rubin

Wavelets are waveform functions that describe transient and unstable variations, such as noises. In this work, we study the advantages of discrete and continuous wavelet transforms (DWT and CWT) of microlensing data to denoise them and…

Instrumentation and Methods for Astrophysics · Physics 2023-10-06 Sedighe Sajadian , Hossein Fatheddin

A method is described by which a function defined on a cubic grid (as from a finite difference solution of a partial differential equation) can be resolved into spherical harmonic components at some fixed radius. This has applications to…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Charles W. Misner

This paper has three main contributions. The first is the construction of wavelet transforms from B-spline scaling functions defined on a grid of non-equispaced knots. The new construction extends the equispaced, biorthogonal, compactly…

Statistics Theory · Mathematics 2016-10-20 Maarten Jansen

A fast algorithm for Antoine and Vandergheynst's (1998) directional continuous spherical wavelet transform (CSWT) is presented. Computational requirements are reduced by a factor of O(\sqrt{N}), when N is the number of pixels on the sphere.…

Astrophysics · Physics 2007-05-23 J. D. McEwen , M. P. Hobson , A. N. Lasenby , D. J. Mortlock

Image enhancement is a technique that frequently utilized in digital image processing. In recent years, the popularity of learning-based techniques for enhancing the aesthetic performance of photographs has increased. However, the majority…

Computer Vision and Pattern Recognition · Computer Science 2022-12-20 Zinuo Li , Xuhang Chen , Chi-Man Pun , Shuqiang Wang

Recovering a function from its integrals over circular cones recently gained significance because of its relevance to novel medical imaging technologies such emission tomography using Compton cameras. In this paper we investigate the case…

Numerical Analysis · Mathematics 2016-06-14 Daniela Schiefeneder , Markus Haltmeier