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Related papers: Approximating W projection as a separable kernel

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Incorporating wide-field considerations in interferometric imaging is of increasing importance for next-generation radio telescopes. Compressed sensing techniques for interferometric imaging have been extended to wide fields recently,…

Instrumentation and Methods for Astrophysics · Physics 2011-08-29 J. D. McEwen , Y. Wiaux

Radio interferometers do not measure the sky brightness distribution directly but rather a modified Fourier transform of it. Imaging algorithms, thus, need a computational representation of the linear measurement operator and its adjoint,…

Instrumentation and Methods for Astrophysics · Physics 2021-02-10 Philipp Arras , Martin Reinecke , Rüdiger Westermann , Torsten A. Enßlin

Approximation of non-linear kernels using random feature maps has become a powerful technique for scaling kernel methods to large datasets. We propose $\textit{Tensor Sketch}$, an efficient random feature map for approximating polynomial…

Data Structures and Algorithms · Computer Science 2025-05-20 Ninh Pham , Rasmus Pagh

Increasing the angular resolution of an interferometric array requires placing its elements at large separations. This often leads to sparse coverage and introduces challenges to reconstructing images from interferometric data. We introduce…

Instrumentation and Methods for Astrophysics · Physics 2024-12-04 Dimitrios Psaltis , Feryal Ozel , Yassine Ben Zineb

It was demonstrated in earlier work that, by approximating its range kernel using shiftable functions, the non-linear bilateral filter can be computed using a series of fast convolutions. Previous approaches based on shiftable approximation…

Computer Vision and Pattern Recognition · Computer Science 2016-04-20 Sanjay Ghosh , Kunal N. Chaudhury

Kernel methods are powerful and flexible approach to solve many problems in machine learning. Due to the pairwise evaluations in kernel methods, the complexity of kernel computation grows as the data size increases; thus the applicability…

Machine Learning · Computer Science 2017-11-28 Bharath Bhushan Damodaran , Nicolas Courty , Philippe-Henri Gosselin

Nonuniform Fourier data are routinely collected in applications such as magnetic resonance imaging, synthetic aperture radar, and synthetic imaging in radio astronomy. To acquire a fast reconstruction that does not require an online inverse…

Numerical Analysis · Mathematics 2016-10-05 Anne Gelb , Guohui Song

Upcoming radio interferometers are aiming to image the sky at new levels of resolution and sensitivity, with wide-band image cubes reaching close to the Petabyte scale for SKA. Modern proximal optimization algorithms have shown a potential…

Instrumentation and Methods for Astrophysics · Physics 2023-08-22 Pierre-Antoine Thouvenin , Abdullah Abdulaziz , Arwa Dabbech , Audrey Repetti , Yves Wiaux

Kernel-phase is a recently developed paradigm that tackles the classical problem of image deconvolution, based on an interferometric point of view of image formation. Kernel-phase inherits and borrows from the notion of closure-phase,…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 Frantz Martinache

Photonic convolutional accelerators have emerged as low-energy alternatives to power-demanding digital convolutional neural networks, though they often face limitations in scalability. In this work, we introduce a convolutional photonic…

Optics · Physics 2025-12-24 Georgios Moustakas , Adonis Bogris , Charis Mesaritakis

Quantum imaging has a potential of enhancing precision of the object reconstruction by using quantum correlations of the imaging field. This is especially important for imaging requiring low-intensity fields up to the level of few-photons.…

We describe a scalable distributed imaging algorithm framework for next-generation radio telescopes, managing the Fourier transform from apertures to sky (or vice versa) with a focus on minimising memory load, data transfers, and…

Instrumentation and Methods for Astrophysics · Physics 2024-07-17 Peter Wortmann , James Kent , Bojan Nikolic

A common challenge in nonparametric inference is its high computational complexity when data volume is large. In this paper, we develop computationally efficient nonparametric testing by employing a random projection strategy. In the…

Statistics Theory · Mathematics 2018-02-20 Meimei Liu , Zuofeng Shang , Guang Cheng

Purpose: To develop an algorithm for robust partial Fourier (PF) reconstruction applicable to diffusion-weighted (DW) images with non-smooth phase variations. Methods: Based on an unrolled proximal splitting algorithm, a neural network…

Image and Video Processing · Electrical Eng. & Systems 2022-01-11 Fasil Gadjimuradov , Thomas Benkert , Marcel Dominik Nickel , Andreas Maier

In this paper we consider the fundamental operations dilation and erosion of mathematical morphology. Many powerful image filtering operations are based on their combinations. We establish homomorphism between max-plus semi-ring of integers…

Image and Video Processing · Electrical Eng. & Systems 2023-05-05 Vivek Sridhar , Keyvan Shahin , Michael Breuß , Marc Reichenbach

Deep Learning-based Computer Vision field has recently been trying to explore larger kernels for convolution to effectively scale up Convolutional Neural Networks. Simultaneously, new paradigm of models such as Vision Transformers find it…

Computer Vision and Pattern Recognition · Computer Science 2023-02-24 Siddharth Agrawal

Kernel methods are a highly effective and widely used collection of modern machine learning algorithms. A fundamental limitation of virtually all such methods are computations involving the kernel matrix that naively scale quadratically…

Machine Learning · Computer Science 2021-06-09 John Paul Ryan , Sebastian Ament , Carla P. Gomes , Anil Damle

We extend the diffusion-map formalism to data sets that are induced by asymmetric kernels. Analytical convergence results of the resulting expansion are proved, and an algorithm is proposed to perform the dimensional reduction. In this work…

Machine Learning · Computer Science 2024-01-24 Alvaro Almeida Gomez , Antonio Silva Neto , Jorge zubelli

An important component of many image alignment methods is the calculation of inner products (correlations) between an image of $n\times n$ pixels and another image translated by some shift and rotated by some angle. For robust alignment of…

Numerical Analysis · Mathematics 2020-02-19 Aaditya Rangan , Marina Spivak , Joakim Andén , Alex Barnett

A scheme for approximating the kernel $w$ of the fractional $\alpha$-integral by a linear combination of exponentials is proposed and studied. The scheme is based on the application of a composite Gauss-Jacobi quadrature rule to an integral…

Numerical Analysis · Mathematics 2018-10-12 Daniel Baffet