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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

Interpreting spectropolarimetric observations of the solar atmosphere takes much longer than the acquiring the data. The most important reason for this is that the model fitting, or "inversion", used to infer physical quantities from the…

Solar and Stellar Astrophysics · Physics 2020-12-16 Ivan Milic , Ricardo Gafeira

Direct inversion of incomplete visibility samples in VLBI (Very Large Baseline Interferometry) radio telescopes produces images with convolutive artifacts. Since proper analysis and interpretations of astronomical radio sources require a…

Instrumentation and Methods for Astrophysics · Physics 2009-04-06 Andriyan Bayu Suksmono

Compressive sensing is an impressive approach for fast MRI. It aims at reconstructing MR image using only a few under-sampled data in k-space, enhancing the efficiency of the data acquisition. In this study, we propose to learn priors based…

Image and Video Processing · Electrical Eng. & Systems 2019-09-05 Siyuan Wang , Junjie Lv , Yuanyuan Hu , Dong Liang , Minghui Zhang , Qiegen Liu

The Earth's ionosphere refracts radio waves incident on an interferometer, resulting in shifts to the measured positions of radio sources. We present a method to smoothly remove these shifts and restore sources to their reference positions,…

Instrumentation and Methods for Astrophysics · Physics 2018-08-27 N. Hurley-Walker , P. J. Hancock

X-Ray radiographs are one of the primary results from inertial confinement fusion (ICF) experiments. Issues such as scarcity of experimental data, high levels of noise in the data, lack of ground truth data, and low resolution of data limit…

Plasma Physics · Physics 2022-11-10 Michael Falato , Bradley Wolfe , Nga Nguyen , Xinhua Zhang , Zhehui Wang

Wavefront shaping correction makes it possible to image fluorescent particles deep inside scattering tissue. This requires determining a correction mask to be placed in both excitation and emission paths. Standard approaches select…

Optics · Physics 2022-06-22 Dror Aizik , Ioannis Gkioulekas , Anat Levin

We describe S2LET, a fast and robust implementation of the scale-discretised wavelet transform on the sphere. Wavelets are constructed through a tiling of the harmonic line and can be used to probe spatially localised, scale-depended…

Information Theory · Computer Science 2013-10-29 B. Leistedt , J. D. McEwen , P. Vandergheynst , Y. Wiaux

We propose an image-based flow decomposition developed from the two-dimensional (2D) tensor empirical wavelet transform (EWT) (Gilles 2013). The idea is to decompose the instantaneous flow data, or its visualisation, adaptively according to…

Fluid Dynamics · Physics 2020-12-24 Jie Ren , Xuerui Mao , Song Fu

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

Photomultiplier tubes (PMTs) are extensively employed as photosensors in neutrino and dark matter detection. The precise charge and timing information extracted from the PMT waveform plays a crucial role in energy and vertex reconstruction.…

Instrumentation and Detectors · Physics 2025-02-14 Jingzhe Tang , Tianying Xiao , Xuan Tang , Yongbo Huang

Decomposition of digital signals and images into other basis or dictionaries than time or space domains is a very common approach in signal and image processing and analysis. Such a decomposition is commonly obtained using fixed transforms…

Signal Processing · Electrical Eng. & Systems 2021-05-04 Sayantan Dutta , Adrian Basarab , Bertrand Georgeot , Denis Kouamé

This paper presents a case study from a single, six-hour observing period to illustrate the application of techniques developed for interferometric radio telescopes to the spectral analysis of observations of ionospheric fluctuations with…

Space Physics · Physics 2014-02-05 Joseph Helmboldt , Huib Intema

Atom interferometers are sensitive to a wide range of forces by encoding their signals in interference patterns of matter waves. To estimate the magnitude of these forces, the underlying phase shifts they imprint on the atoms must be…

We present in this paper new multiscale transforms on the sphere, namely the isotropic undecimated wavelet transform, the pyramidal wavelet transform, the ridgelet transform and the curvelet transform. All of these transforms can be…

Astrophysics · Physics 2016-08-30 Jean-Luc Starck , Yassir Moudden , Pierrick Abrial , Mai Nguyen

In this paper, we propose a novel design of image deblurring in the form of one-shot convolution filtering that can directly convolve with naturally blurred images for restoration. The problem of optical blurring is a common disadvantage to…

Image and Video Processing · Electrical Eng. & Systems 2019-07-22 Mahdi S. Hosseini , Konstantinos N. Plataniotis

We present a new technique of decontaminating Swift UVOT grism spectra for transient objects. We describe the template image requirements and image processing steps necessary to successfully implement the empirical decontamination…

Instrumentation and Methods for Astrophysics · Physics 2016-04-27 Michael T. Smitka , Peter J. Brown , Paul Kuin , Nicholas B. Suntzeff

Convolution is a central operation in Convolutional Neural Networks (CNNs), which applies a kernel to overlapping regions shifted across the image. However, because of the strong correlations in real-world image data, convolutional kernels…

The aim of this paper is to show the usefulness of Meyer wavelets for the classical problem of density estimation and for density deconvolution from noisy observations. By using such wavelets, the computation of the empirical wavelet…

Statistics Theory · Mathematics 2009-03-27 Jeremie Bigot

Light field cameras provide intriguing possibilities, such as post-capture refocus or the ability to synthesize images from novel viewpoints. This comes, however, at the price of significant storage requirements. Compression techniques can…

Graphics · Computer Science 2019-10-14 Christian Lessig