English
Related papers

Related papers: A spectral mean for point sampled closed curves

200 papers

Diffusion models are typically trained using pointwise reconstruction objectives that are agnostic to the spectral and multi-scale structure of natural signals. We propose a loss-level spectral regularization framework that augments…

Machine Learning · Computer Science 2026-03-04 Satish Chandran , Nicolas Roque dos Santos , Yunshu Wu , Greg Ver Steeg , Evangelos Papalexakis

We present a new implementation of anisotropic mean curvature flow for contour recognition. Our procedure couples the mean curvature flow of planar closed smooth curves, with an external field from a potential of point-wise charges. This…

Differential Geometry · Mathematics 2024-04-08 P. Suárez-Serrato , E. I. Velázquez Richards

Some types of medical and topographic imaging device produce images in which the pixel values are "phase-wrapped", i.e. measured modulus a known scalar. Phase unwrapping can be viewed as the problem of inferring the number of shifts between…

Computer Vision and Pattern Recognition · Computer Science 2013-01-14 Kannan Achan , Brendan J. Frey , Ralf Koetter

In this work, our aim is to reconstruct the unknown initial value from terminal data. We develop a numerical framework on nonuniform time grids for fractional wave equations under the lower regularity assumptions. Then, we introduce a…

Numerical Analysis · Mathematics 2025-06-25 Dakang Cen , Zhiyuan Li , Wenlong Zhang

A new class of statistical deformable models is introduced to study high-dimensional curves or images. In addition to the standard measurement error term, these deformable models include an extra error term modeling the individual…

Statistics Theory · Mathematics 2011-08-24 Jérémie Bigot , Benjamin Charlier

In this work, we present the misspecified Gaussian Cram\'er-Rao lower bound for the parameters of a harmonic signal, or pitch, when signal measurements are collected from an almost, but not quite, harmonic model. For the asymptotic case of…

Signal Processing · Electrical Eng. & Systems 2019-10-29 Filip Elvander , Jie Ding , Andreas Jakobsson

The problem of mean square optimal estimation of linear functionals which depend on the unobserved values of a periodically correlated stochastic sequence is considered. The estimates are based on observations of the sequence with a noise.…

Statistics Theory · Mathematics 2020-02-12 Iryna Golichenko , Mikhail Moklyachuk

Point Spread Function (PSF) for imaging through inhomogeneous refractive medium, such as atmospheric turbulence is bounded by three constraints [Charnotskii, Opt. Eng., 52, 04600, (2013)]. PSF is non-negative, band-limited, and the third…

Optics · Physics 2022-07-06 Mikhail Charnotskii

We introduce and analyze the concept of space-spectrum uncertainty for certain commonly-used designs for spectrally programmable cameras. Our key finding states that, it is impossible to simultaneously capture high-resolution spatial images…

Image and Video Processing · Electrical Eng. & Systems 2021-01-01 Vishwanath Saragadam , Aswin Sankaranarayanan

We consider the problem of shape restricted nonparametric regression on a closed set X ?\in R; where it is reasonable to assume the function has no more than H local extrema interior to X: Following a Bayesian approach we develop a…

Methodology · Statistics 2016-04-06 Matthew W. Wheeler , David B. Dunson , Amy H. Herring

This paper addresses the problem of segmenting a stream of graph signals: we aim to detect changes in the mean of a multivariate signal defined over the nodes of a known graph. We propose an offline method that relies on the concept of…

Machine Learning · Computer Science 2024-03-01 Alejandro de la Concha , Nicolas Vayatis , Argyris Kalogeratos

We present a simple and effective method to eliminate system aberrations and speckle noise in quantitative phase imaging. Using spiral integration, complete information about system aberration is calculated from three laterally shifted…

Biological Physics · Physics 2018-02-14 Inhyeok Choi , Kyeoreh Lee , YongKeun Park

Spherical regression explores relationships between variables on spherical domains. We develop a nonparametric model that uses a diffeomorphic map from a sphere to itself. The restriction of this mapping to diffeomorphisms is natural in…

Other Statistics · Statistics 2017-02-06 Michael Rosenthal , Wei Wu , Eric Klassen , Anuj Srivastava

The problem of the mean-square optimal linear estimation of functionals which depend on the unknown values of a stationary stochastic sequence from observations of the sequence with noise is considered. In the case of spectral certainty,…

Statistics Theory · Mathematics 2024-06-25 Maksym Luz , Mikhail Moklyachuk

1. Parameter inference from distorted measurements is discussed. 2. Smeared measurements are unfolded without explicit regularization. The corresponding results are unbiased and permit to fit parameters and to apply quantitative…

Data Analysis, Statistics and Probability · Physics 2016-07-26 Guenter Zech

In this paper, we consider the problem of estimating the covariance kernel and its eigenvalues and eigenfunctions from sparse, irregularly observed, noise corrupted and (possibly) correlated functional data. We present a method based on…

Methodology · Statistics 2008-07-09 Debashis Paul , Jie Peng

Channeled spectropolarimetry measures the spectrally resolved Stokes parameters. A key aspect of this technique is to accurately reconstruct the Stokes parameters from a modulated measurement of the channeled spectropolarimeter. The…

Instrumentation and Detectors · Physics 2018-02-15 Dennis J. Lee , Charles F. LaCasse , Julia M. Craven

In this paper, we propose a numerical method to approximate the solution of partial differential equations in irregular domains with no-flux boundary conditions by means of spectral methods. The main features of this method are its…

Numerical Analysis · Mathematics 2007-05-23 Alfonso Bueno-Orovio , Victor M. Perez-Garcia , Flavio H. Fenton

This paper proposes a fast and accurate surface normal estimation method which can be directly used on depth maps (organized point clouds). The surface normal estimation process is formulated as a closed-form expression. In order to reduce…

Computer Vision and Pattern Recognition · Computer Science 2022-09-20 Saed Moradi , Alireza Memarmoghadam , Denis Laurendeau

We develop a systematic study about the spectrality of measures supported on piecewise smooth curves by studying the support of the tempered distributions arising from the tiling equation of some singular spectral measures. In doing so, we…

Classical Analysis and ODEs · Mathematics 2025-07-02 Mihail N. Kolountzakis , Chun-Kit Lai