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Aims : We describe MS-MFS, a multi-scale multi-frequency deconvolution algorithm for wide-band synthesis-imaging, and present imaging results that illustrate the capabilities of the algorithm and the conditions under which it is feasible…

Instrumentation and Methods for Astrophysics · Physics 2015-05-28 Urvashi Rau , Tim J. Cornwell

Given the incomplete sampling of spatial frequencies by radio interferometers, achieving precise restoration of astrophysical information remains challenging. To address this ill-posed problem, compressive sensing(CS) provides a robust…

Instrumentation and Methods for Astrophysics · Physics 2025-05-09 Lei Yu , Bin Liu , Cheng-Jin Jin , Ru-Rong Chen , Hong-Wei Xi , Bo Peng

We present a method for subtracting point sources from interferometric radio images via forward modeling of the instrument response and involving an algebraic nonlinear minimization. The method is applied to simulated maps of the Murchison…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 G. Bernardi , D. A. Mitchell , S. M. Ord , L. J. Greenhill , B. Pindor , R. B. Wayth , J. S. B. Wyithe

We introduce a new technique for imaging the polarized radio sky using interferometric data. The new approach, which we call Faraday synthesis, combines aperture and rotation measure synthesis imaging and deconvolution into a single…

Instrumentation and Methods for Astrophysics · Physics 2015-06-03 M. R. Bell , T. A. Enßlin

As ground-based all-sky astronomical surveys will gather millions of images in the coming years, a critical requirement emerges for the development of fast deconvolution algorithms capable of efficiently improving the spatial resolution of…

Instrumentation and Methods for Astrophysics · Physics 2024-07-31 Utsav Akhaury , Pascale Jablonka , Jean-Luc Starck , Frédéric Courbin

We present a new detection algorithm based on the wavelet transform for the analysis of high energy astronomical images. The wavelet transform, due to its multi-scale structure, is suited for the optimal detection of point-like as well as…

In this work, an efficient numerical scheme is presented for seismic blind deconvolution in a multichannel scenario. The proposed method iterate with wo steps: first, wavelet estimation across all channels and second, refinement of the…

Computational Physics · Physics 2020-10-20 Naveed Iqbal , Entao Liu , James H. McClellan , Abdullatif A. Al-Shuhail

Estimating accurate high-dimensional transformations remains very challenging, especially in a clinical setting. In this paper, we introduce a multiscale parameterization of deformations to enhance registration and atlas estimation in the…

Optimization and Control · Mathematics 2025-01-31 Fleur Gaudfernau , Eléonore Blondiaux , Stéphanie Allassonnière , Erwan Le Pennec

The increased sensitivity of future radio telescopes will result in requirements for higher dynamic range within the image as well as better resolution and immunity to interference. In this paper we propose a new matrix formulation of the…

Astrophysics · Physics 2014-11-18 Chen Ben-David , Amir Leshem

Successful wavelet estimation is an essential step for seismic methods like impedance inversion, analysis of amplitude variations with offset and full waveform inversion. Homomorphic deconvolution has long intrigued as a potentially elegant…

Geophysics · Physics 2013-01-10 Roberto H. Herrera , Mirko Van der Baan

This letter presents a novel hybrid method that leverages deep learning to exploit the multi-resolution analysis capability of the wavelets, in order to denoise a photoplethysmography (PPG) signal. Under the proposed method, a noisy PPG…

Information Theory · Computer Science 2023-01-18 Rabia Ahmed , Ahsan Mehmood , Muhammad Mahboob Ur Rahman , Octavia A. Dobre

Ground-based astronomical observations will continue to produce resolution-limited images due to atmospheric seeing. Deconvolution reverses such effects and thus can benefit extracted science in multifaceted ways. We apply the Scaled…

Instrumentation and Methods for Astrophysics · Physics 2025-11-04 Yash Gondhalekar , Richard M. Feder , Matthew J. Graham , Ajit K. Kembhavi , Margarita Safonova , Snehanshu Saha , Ashish A. Mahabal

Laser-driven ion beams are defined by a number of unique features, including a large spread in energy. A stack configuration of radiochromic film (RCF) can be utilized to characterize such beams through measurements of their energy spectra.…

Instrumentation and Detectors · Physics 2023-01-23 S. McCallum , G. Milluzzo , M. Borghesi , A. Subiel , F. Romano

Wide-field imaging has become a major challenge for modern radio astronomy, which uses high sensitivity acquisition systems that deal with huge amounts of data. In this paper we investigate a fast wide-field imaging solution based on the…

Instrumentation and Methods for Astrophysics · Physics 2019-04-19 Luis F. R. Lucas , Chris J. Skipper , Anna M. M. Scaife

The rise of machine learning in image processing has created a gap between trainable data-driven and classical model-driven approaches: While learning-based models often show superior performance, classical ones are often more transparent.…

Image and Video Processing · Electrical Eng. & Systems 2020-04-15 Tobias Alt , Joachim Weickert

An optical imaging system forms an object image by recollecting light scattered by the object. However, intact optical information of the object delivered through the imaging system is deteriorated by imperfect optical elements and unwanted…

Optics · Physics 2017-03-28 SangYun Lee , Kyeoreh Lee , Seungwoo Shin , YongKeun Park

The study of astronomical phenomena through ground-based observations is always challenged by the distorting effects of Earth's atmosphere. Traditional methods of post-facto image correction, essential for correcting these distortions,…

Instrumentation and Methods for Astrophysics · Physics 2024-08-14 A. Asensio Ramos

We present two algorithms to identify and flag radio frequency interference (RFI) in radio interferometric imaging data. The first algorithm utilizes the redundancy of visibilities inside a UV cell in the visibility plane to identify…

Instrumentation and Methods for Astrophysics · Physics 2018-06-27 Srikrishna Sekhar , Ramana Athreya

This paper addresses the problem of high-resolution Doppler blood flow estimation from an ultrafast sequence of ultrasound images. Formulating the separation of clutter and blood components as an inverse problem has been shown in the…

Image and Video Processing · Electrical Eng. & Systems 2020-07-13 Duong-Hung Pham , Adrian Basarab , Ilyess Zemmoura , Jean-Pierre Remenieras , Denis Kouame

Wavelets are scaleable, oscillatory functions that deviate from zero only within a limited spatial regime and have average value zero. In addition to their use as source characterizers, wavelet functions are rapidly gaining currency within…

Astrophysics · Physics 2009-11-07 Peter E. Freeman , Vinay Kashyap , Robert Rosner , Donald Q. Lamb