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Numerous regularization methods for deformable image registration aim at enforcing smooth transformations, but are difficult to tune-in a priori and lack a clear physical basis. Physically inspired strategies have emerged, offering a sound…

Image and Video Processing · Electrical Eng. & Systems 2023-12-27 Pablo Alvarez , Stéphane Cotin

We present a new inner-outer iterative algorithm for edge enhancement in imaging problems. At each outer iteration, we formulate a Tikhonov-regularized problem where the penalization is expressed in the 2-norm and involves a regularization…

Numerical Analysis · Mathematics 2020-12-30 Silvia Gazzola , Misha E. Kilmer , James G. Nagy , Oguz Semerici , Eric L. Miller

We consider the estimation of the regularization parameter for the simultaneous deblurring of multiple noisy images via Tikhonov regularization. We approach the problem in three ways. We first reduce the problem to a single-image deblurring…

Astrophysics · Physics 2009-11-10 R. Vio , P. Ma , W. Zhong , J. Nagy , L. Tenorio , W. Wamsteker

Deformable image registration is a standard engineering problem used to determine the distortion experienced by a body by comparing two images of it in different states. This study introduces two new DIR methods designed to capture…

Computer Vision and Pattern Recognition · Computer Science 2024-09-04 Daniel E. Hurtado , Axel Osses , Rodrigo Quezada

We propose a novel non-rigid image registration algorithm that is built upon fully convolutional networks (FCNs) to optimize and learn spatial transformations between pairs of images to be registered. Different from most existing deep…

Computer Vision and Pattern Recognition · Computer Science 2017-09-05 Hongming Li , Yong Fan

Gaussian Markov random fields (GMRFs) are useful in a broad range of applications. In this paper we tackle the problem of learning a sparse GMRF in a high-dimensional space. Our approach uses the l1-norm as a regularization on the inverse…

Machine Learning · Computer Science 2012-06-18 John Duchi , Stephen Gould , Daphne Koller

In this article we study the problem of recovering the unknown solution of a linear ill-posed problem, via iterative regularization methods. We review the problem of projection-regularization from a statistical point of view. A basic…

Statistics Theory · Mathematics 2007-06-13 Ana K. Fermin , Carenne Ludena

Non-rigid registration is a crucial task with applications in medical imaging, industrial robotics, computer vision, and entertainment. Standard approaches accomplish this task using variations on the Non-Rigid Iterative Closest Point…

Graphics · Computer Science 2025-10-22 Gabrielle Browne , Mengfei Liu , Eitan Grinspun , Otman Benchekroun

Understanding the orientation of geological structures is crucial for analyzing the complexity of the Earths' subsurface. For instance, information about geological structure orientation can be incorporated into local anisotropic…

Geophysics · Physics 2024-09-10 Ali Gholami , Silvia Gazzola

We present an adaptive regularization scheme for optimizing composite energy functionals arising in image analysis problems. The scheme automatically trades off data fidelity and regularization depending on the current data fit during the…

Computer Vision and Pattern Recognition · Computer Science 2017-05-10 Byung-Woo Hong , Ja-Keoung Koo , Martin Burger , Stefano Soatto

We consider the statistical inverse problem of recovering a function $f: M \to \mathbb R$, where $M$ is a smooth compact Riemannian manifold with boundary, from measurements of general $X$-ray transforms $I_a(f)$ of $f$, corrupted by…

Statistics Theory · Mathematics 2018-02-14 François Monard , Richard Nickl , Gabriel P. Paternain

Non-Gaussian and multimodal distributions are an important part of many recent robust sensor fusion algorithms. In difference to robust cost functions, they are probabilistically founded and have good convergence properties. Since their…

Robotics · Computer Science 2020-01-14 Tim Pfeifer , Peter Protzel

Image segmentation is a crucial but challenging task that has many applications. In medical imaging for instance, intensity inhomogeneity and noise are common. In thigh muscle images, different muscles are closed packed together and there…

Computer Vision and Pattern Recognition · Computer Science 2022-03-30 Haifeng Li , Weihong Guo , Jun Liu , Li Cui , Dongxing Xie

Surface registration, the task of aligning several multidimensional point sets, is a necessary task in many scientific fields. In this work, a novel statistical approach is developed to solve the problem of nonrigid registration. While the…

Methodology · Statistics 2020-06-15 Ashton Wiens , William Kleiber , Douglas Nychka , Katherine R. Barnhart

In this paper we present a new regularization term for variational image restoration which can be regarded as a space-variant anisotropic extension of the classical isotropic Total Variation (TV) regularizer. The proposed regularizer comes…

Image and Video Processing · Electrical Eng. & Systems 2019-08-05 Luca Calatroni , Alessandro Lanza , Monica Pragliola , Fiorella Sgallari

A critical task in graph signal processing is to estimate the true signal from noisy observations over a subset of nodes, also known as the reconstruction problem. In this paper, we propose a node-adaptive regularization for graph signal…

Signal Processing · Electrical Eng. & Systems 2021-02-08 Maosheng Yang , Mario Coutino , Geert Leus , Elvin Isufi

Regularization techniques are necessary to compute meaningful solutions to discrete ill-posed inverse problems. The well-known 2-norm Tikhonov regularization method equipped with a discretization of the gradient operator as regularization…

Numerical Analysis · Mathematics 2024-06-05 Silvia Gazzola , Ali Gholami

Pairwise Markov Random Fields (MRFs) or undirected graphical models are parsimonious representations of joint probability distributions. Variables correspond to nodes of a graph, with edges between nodes corresponding to conditional…

Statistics Theory · Mathematics 2018-09-18 Eric Janofsky

Solving inverse problems involving measurement noise and modeling errors requires regularization in order to avoid data overfit. Geophysical inverse problems, in which the Earth's highly heterogeneous structure is unknown, present a…

Geophysics · Physics 2022-03-31 Ali Siahkoohi , Rafael Orozco , Gabrio Rizzuti , Felix J. Herrmann

This paper proposes a general framework for internal patch-based image restoration based on Conditional Random Fields (CRF). Unlike related models based on Markov Random Fields (MRF), our approach explicitly formulates the posterior…

Computer Vision and Pattern Recognition · Computer Science 2018-07-10 Milad Niknejad , Jose M. Bioucas-Dias , Mario A. T. Figueiredo