English
Related papers

Related papers: Computing spatial information from Fourier coeffic…

200 papers

Ptychography is a popular imaging technique that combines diffractive imaging with scanning microscopy. The technique consists of a coherent beam that is scanned across an object in a series of overlapping positions, leading to reliable and…

Numerical Analysis · Mathematics 2024-08-08 Ricardo Parada , Samy Wu Fung , Stanley Osher

A two-dimensional Fourier transform of hadron form factors allows to determine their charge density in transverse space. We show that this method can be applied to any virtual photon induced transition, such as \gamma *(q)+N -> \pi N. Only…

High Energy Physics - Phenomenology · Physics 2011-06-13 Paul Hoyer , Samu Kurki

We investigated the use of the Bayesian inference to restore noise-degraded images under conditions of spatially correlated noise. The generative statistical models used for the original image and the noise were assumed to obey…

Disordered Systems and Neural Networks · Physics 2009-11-07 Jun Tsuzurugi , Masato Okada

Quantum information processing and its subfield, quantum image processing, are rapidly growing fields as a result of advancements in the practicality of quantum mechanics. In this paper, we propose a quantum algorithm for processing…

Quantum Physics · Physics 2024-10-17 Ze Yu Zhang , Weibo Gao

Image identification is one of the most challenging tasks in different areas of computer vision. Scale-invariant feature transform is an algorithm to detect and describe local features in images to further use them as an image matching…

Computer Vision and Pattern Recognition · Computer Science 2018-03-15 Ebrahim Karami , Mohamed Shehata , Andrew Smith

Fourier single-pixel imaging (FSI) is a data-efficient single-pixel imaging (SPI). However, there is still a serious challenge to obtain higher imaging quality using fewer measurements, which limits the development of real-time SPI. In this…

Image and Video Processing · Electrical Eng. & Systems 2023-11-07 Huan Cui , Jie Cao , Qun Hao , Haoyu Zhang , Chang Zhou

A physical field has an infinite number of degrees of freedom since it has a field value at each location of a continuous space. Therefore, it is impossible to know a field from finite measurements alone and prior information on the field…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-12 Torsten A. Enßlin

The dominant paradigm in computational materials discovery relies on heavily parameterized deep architectures, including message-passing graph networks and equivariant models, that require millions of DFT-labeled training structures and…

Materials Science · Physics 2026-05-19 Pranoy Ray , Surya R. Kalidindi

The Fourier transformation is an effective and efficient operation of Gaussianization at the one-point level. Using a set of N-body simulation data, we verified that the one-point distribution functions of the dark matter momentum…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-05 Ming Li , Jun Pan , Pengjie Zhang , Jie Wang , Longlong Feng , Liang Gao , Xi Kang , Guoliang Li , Weipeng Lin , Haihui Wang

We present a novel algorithm, named the 2D-FFAST, to compute a sparse 2D-Discrete Fourier Transform (2D-DFT) featuring both low sample complexity and low computational complexity. The proposed algorithm is based on mixed concepts from…

Information Theory · Computer Science 2015-09-22 Frank Ong , Sameer Pawar , Kannan Ramchandran

Bayesian statistical inference is a powerful tool for model-data comparisons and extractions of physical parameters that are often unknown functions of system variables. Existing Bayesian analyses often rely on explicit parametrizations of…

High Energy Physics - Phenomenology · Physics 2023-08-09 Man Xie , Weiyao Ke , Hanzhong Zhang , Xin-Nian Wang

A new method of quantum state tomography for quantum information processing is described. The method based on two-dimensional Fourier transform technique involves detection of all the off-diagonal elements of the density matrix in a…

Quantum Physics · Physics 2009-11-07 Ranabir Das , T. S. Mahesh , Anil Kumar

Non-parametric imaging and data analysis in astrophysics and cosmology can be addressed by information field theory (IFT), a means of Bayesian, data based inference on spatially distributed signal fields. IFT is a statistical field theory,…

Instrumentation and Methods for Astrophysics · Physics 2015-06-19 Torsten Enßlin

Filtering of digital signals is accomplished on an Excel spreadsheet using fast Fourier transform (FFT) convolution in which the kernel is either a Gaussian or a cosine modulated Gaussian. Pedagogical examples of low-pass and band-pass…

General Physics · Physics 2007-05-23 Randall D. Peters

Multimodal image alignment is the process of finding spatial correspondences between images formed by different imaging techniques or under different conditions, to facilitate heterogeneous data fusion and correlative analysis. The…

Computer Vision and Pattern Recognition · Computer Science 2022-07-01 Johan Öfverstedt , Joakim Lindblad , Nataša Sladoje

To obtain the initial pressure from the collected data on a planar sensor arrangement in Photoacoustic tomography, there exists an exact analytic frequency domain reconstruction formula. An efficient realization of this formula needs to…

Numerical Analysis · Mathematics 2015-01-14 Julian Schmid , Thomas Glatz , Behrooz Zabihian , Mengyang Liu , Wolfgang Drexler , Otmar Scherzer

Image subtraction in astronomy is a tool for transient object discovery such as asteroids, extra-solar planets and supernovae. To match point spread functions (PSFs) between images of the same field taken at different times a convolution…

Instrumentation and Methods for Astrophysics · Physics 2013-05-30 Steven Hartung , Hemant Shukla , J. Patrick Miller , Carlton Pennypacker

Fourier ptychography (FP) is an enabling imaging technique that produces high-resolution complex-valued images with extended field coverages. However, when FP images a phase object with any specific spatial frequency, the captured images…

Fourier methods are fundamental tools to analyze random fields. Statistical structures of homogeneous Gaussian random fields are completely characterized by the power spectrum. In non-Gaussian random fields, polyspectra, higher-order…

Astrophysics · Physics 2009-11-11 Takahiko Matsubara

We present a method for the numerical computation of Fourier-Bessel transforms on a finite or infinite interval. The function to be transformed needs to be evaluated on a grid of points that is independent of the argument of the Bessel…

High Energy Physics - Phenomenology · Physics 2024-08-21 Markus Diehl , Oskar Grocholski