English
Related papers

Related papers: Isospectralization, or how to hear shape, style, a…

200 papers

We consider the problem of finding universal bounds of "isoperimetric" or "isodiametric" type on the spectral gap of the Laplacian on a metric graph with natural boundary conditions at the vertices, in terms of various analytical and…

Spectral Theory · Mathematics 2016-08-24 James B. Kennedy , Pavel Kurasov , Gabriela Malenova , Delio Mugnolo

In inverse scattering problems, a model that allows for the simultaneous recovery of both the domain shape and an impedance boundary condition covers a wide range of problems with impenetrable domains, including recovering the shape of…

Numerical Analysis · Mathematics 2023-12-01 Travis Askham , Carlos Borges

This paper introduces a new shape-based image reconstruction technique applicable to a large class of imaging problems formulated in a variational sense. Given a collection of shape priors (a shape dictionary), we define our problem as…

Functional Analysis · Mathematics 2013-03-04 Alireza Aghasi , Justin Romberg

Isospectrality of planar domains which are obtained by successive unfolding of a fundamental building block is studied in relation to iso-length spectrality of the corresponding domains. Although an explicit and exact trace formula such as…

Chaotic Dynamics · Physics 2007-05-23 Yuichiro Okada , Akira Shudo

We construct non-trivial continuous isospectral deformations of Riemannian metrics on the ball and on the sphere in $\R^n$ for every $n\geq 9$. The metrics on the sphere can be chosen arbitrarily close to the round metric; in particular,…

Differential Geometry · Mathematics 2009-10-31 Carolyn S. Gordon

We study an effective spectral deformation flow for mode amplitudes $C_n(\tau)$, governed by a second-order self-adjoint operator $\hat{C}$ on a compact interval. The flow is encoded in the multi-function $C(v,\tau,n)$ and exhibits global…

Spectral Theory · Mathematics 2026-03-19 Anton Alexa

With the increase in computational power for the available hardware, the demand for high-resolution data in computer graphics applications increases. Consequently, classical geometry processing techniques based on linear algebra solutions…

Graphics · Computer Science 2024-10-08 Filippo Maggioli , Daniele Baieri , Zorah Lähner , Simone Melzi

The availability of affordable and portable depth sensors has made scanning objects and people simpler than ever. However, dealing with occlusions and missing parts is still a significant challenge. The problem of reconstructing a (possibly…

Computer Vision and Pattern Recognition · Computer Science 2018-04-05 Or Litany , Alex Bronstein , Michael Bronstein , Ameesh Makadia

In two-dimensional spectrographs, the optical distortions in the spatial and dispersion directions produce variations in the sub-pixel sampling of the background spectrum. Using knowledge of the camera distortions and the curvature of the…

Astrophysics · Physics 2009-12-08 Daniel D. Kelson

Accurate modelling of object deformations is crucial for a wide range of robotic manipulation tasks, where interacting with soft or deformable objects is essential. Current methods struggle to generalise to unseen forces or adapt to new…

Robotics · Computer Science 2025-05-20 Sean M. V. Collins , Brendan Tidd , Mahsa Baktashmotlagh , Peyman Moghadam

Beamforming is an essential step in the ultrasound image formation pipeline and has recently attracted growing interest. An important goal of beamforming is to increase the image spatial resolution, or in other words to narrow down the…

Image and Video Processing · Electrical Eng. & Systems 2022-09-01 Sobhan Goudarzi , Adrian Basarab , Hassan Rivaz

The paper presents a unified, flexible framework for the tasks of audio inpainting, declipping, and dequantization. The concept is further extended to cover analogous degradation models in a transformed domain, e.g. quantization of the…

Audio and Speech Processing · Electrical Eng. & Systems 2021-01-05 Ondřej Mokrý , Pavel Rajmic , Pavel Záviška

Optical interferometers provide multiple wavelength measurements. In order to fully exploit the spectral and spatial resolution of these instruments, new algorithms for image reconstruction have to be developed. Early attempts to deal with…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Éric Thiébaut , Ferréol Soulez , Loïc Denis

Fractals are geometric shapes that can display complex and self-similar patterns found in nature (e.g., clouds and plants). Recent works in visual recognition have leveraged this property to create random fractal images for model…

Computer Vision and Pattern Recognition · Computer Science 2023-03-23 Cheng-Hao Tu , Hong-You Chen , David Carlyn , Wei-Lun Chao

Modern machine learning increasingly leverages the insight that high-dimensional data often lie near low-dimensional, non-linear manifolds, an idea known as the manifold hypothesis. By explicitly modeling the geometric structure of data…

Machine Learning · Computer Science 2026-03-02 Willem Diepeveen , Deanna Needell

Speckle Imaging based on triple correlation is a very efficient image reconstruction technique which is used to retrieve Fourier phase information of the object in presence of atmospheric turbulence. We have developed both Direct Bispectrum…

Instrumentation and Methods for Astrophysics · Physics 2014-09-17 Arun Surya , Swapan K. Saha

This paper tackles the task of uncalibrated photometric stereo for 3D object reconstruction, where both the object shape, object reflectance, and lighting directions are unknown. This is an extremely difficult task, and the challenge is…

Computer Vision and Pattern Recognition · Computer Science 2022-07-19 Junxuan Li , Hongdong Li

Comparison among graphs is ubiquitous in graph analytics. However, it is a hard task in terms of the expressiveness of the employed similarity measure and the efficiency of its computation. Ideally, graph comparison should be invariant to…

Social and Information Networks · Computer Science 2018-05-30 Anton Tsitsulin , Davide Mottin , Panagiotis Karras , Alex Bronstein , Emmanuel Müller

The acoustic inverse obstacle scattering problem consists of determining the shape of a domain from measurements of the scattered far field due to some set of incident fields (probes). For a penetrable object with known sound speed, this…

Numerical Analysis · Mathematics 2023-02-15 Carlos Borges , Manas Rachh , Leslie Greengard

Geometric rectification of images of distorted documents finds wide applications in document digitization and Optical Character Recognition (OCR). Although smoothly curved deformations have been widely investigated by many works, the most…

Computer Vision and Pattern Recognition · Computer Science 2022-12-19 Dong Luo , Pengbo Bo