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Related papers: Beyond $\ell_1$ sparse coding in V1

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Large Vision-Language Models (LVLMs) may produce outputs that are unfaithful to reality, also known as visual hallucinations (VH), which significantly impedes their real-world usage. To alleviate VH, various decoding strategies have been…

Computer Vision and Pattern Recognition · Computer Science 2025-03-24 Xianwei Zhuang , Zhihong Zhu , Yuxin Xie , Liming Liang , Yuexian Zou

Over the past decade, the celebrated sparse representation model has achieved impressive results in various signal and image processing tasks. A convolutional version of this model, termed convolutional sparse coding (CSC), has been…

Signal Processing · Electrical Eng. & Systems 2018-10-03 Ives Rey-Otero , Jeremias Sulam , Michael Elad

Augmenting a smooth cost function with an $\ell_1$ penalty allows analysts to efficiently conduct estimation and variable selection simultaneously in sophisticated models and can be efficiently implemented using proximal gradient methods.…

Machine Learning · Statistics 2024-12-10 Nathan Wycoff , Lisa O. Singh , Ali Arab , Katharine M. Donato

Many real world practical problems can be formulated as $\ell_{0}$-minimization problems with nonnegativity constraints, which seek the sparsest nonnegative signals to underdetermined linear systems. They have been widely applied in signal…

Optimization and Control · Mathematics 2017-08-29 Angang Cui , Haiyang Li , Meng Wen , Jigen Peng

Motivated by the observation that a given signal $\boldsymbol{x}$ admits sparse representations in multiple dictionaries $\boldsymbol{\Psi}_d$ but with varying levels of sparsity across dictionaries, we propose two new algorithms for the…

Information Theory · Computer Science 2015-09-29 Rizwan Ahmad , Philip Schniter

In many linear regression problems, including ill-posed inverse problems in image restoration, the data exhibit some sparse structures that can be used to regularize the inversion. To this end, a classical path is to use $\ell_{12}$ block…

Signal Processing · Electrical Eng. & Systems 2021-10-25 Charles-Alban Deledalle , Nicolas Papadakis , Joseph Salmon , Samuel Vaiter

In this effort, we propose a convex optimization approach based on weighted $\ell_1$-regularization for reconstructing objects of interest, such as signals or images, that are sparse or compressible in a wavelet basis. We recover the…

Image and Video Processing · Electrical Eng. & Systems 2019-09-17 Joseph Daws , Armenak Petrosyan , Hoang Tran , Clayton G. Webster

Mixed norms that promote structured sparsity have numerous applications in signal processing and machine learning problems. In this work, we present a new algorithm, based on a Newton root search technique, for computing the projection onto…

Optimization and Control · Mathematics 2021-03-25 Gustavo Chau , Brendt Wohlberg , Paul Rodriguez

In this paper, we consider the efficient and robust reconstruction of signals and images via $\ell_{1}-\alpha \ell_{2}~(0<\alpha\leq 1)$ minimization in impulsive noise case. To achieve this goal, we introduce two new models: the…

Optimization and Control · Mathematics 2018-10-15 Peng Li , Huanmin Ge , Wengu Chen

Feature hashing and other random projection schemes are commonly used to reduce the dimensionality of feature vectors. The goal is to efficiently project a high-dimensional feature vector living in $\mathbb{R}^n$ into a much…

Machine Learning · Statistics 2020-03-27 Meena Jagadeesan

We propose two sparsity-aware normalized subband adaptive filter (NSAF) algorithms by using the gradient descent method to minimize a combination of the original NSAF cost function and the l1-norm penalty function on the filter…

Signal Processing · Electrical Eng. & Systems 2018-10-18 Y. Yu , H. Zhao , R. C. de Lamare

Weighted $\ell_1$-minimization has been studied as a technique for the reconstruction of a sparse signal from compressively sampled measurements when prior information about the signal, in the form of a support estimate, is available. In…

Information Theory · Computer Science 2016-12-09 Deanna Needell , Rayan Saab , Tina Woolf

In this paper we introduce a nonuniform sparsity model and analyze the performance of an optimized weighted $\ell_1$ minimization over that sparsity model. In particular, we focus on a model where the entries of the unknown vector fall into…

Information Theory · Computer Science 2010-09-21 M. Amin Khajehnejad , Weiyu Xu , A. Salman Avestimehr , Babak Hassibi

INTRODUCTION | Fully supervised 3D segmentation of high-resolution ex vivo MRI is limited by the prohibitive cost of volumetric annotation, forcing reliance on sparse 2D slices. Weakly supervised Sparse-to-Dense frameworks bridge this gap,…

Image and Video Processing · Electrical Eng. & Systems 2026-05-14 Paul Hoareau , Kuan Yi Wang , Brandon Bujak , Roy Sun , Govind Nair , Irene Cortese , Charidimos Tsagkas , Daniel Reich , Julien Cohen-Adad

Compressed sensing aims at reconstructing sparse signals from significantly reduced number of samples, and a popular reconstruction approach is $\ell_1$-norm minimization. In this correspondence, a method called orthonormal expansion is…

Information Theory · Computer Science 2015-05-30 Zai Yang , Cishen Zhang , Jun Deng , Wenmiao Lu

An explicit algorithm for the minimization of an $\ell_1$ penalized least squares functional, with non-separable $\ell_1$ term, is proposed. Each step in the iterative algorithm requires four matrix vector multiplications and a single…

Numerical Analysis · Mathematics 2012-02-01 Ignace Loris , Caroline Verhoeven

In this paper, we study the support recovery guarantees of underdetermined sparse regression using the $\ell_1$-norm as a regularizer and a non-smooth loss function for data fidelity. More precisely, we focus in detail on the cases of…

Information Theory · Computer Science 2016-11-04 Kévin Degraux , Gabriel Peyré , Jalal M. Fadili , Laurent Jacques

In the context of compressed sensing (CS), this paper considers the problem of reconstructing sparse signals with the aid of other given correlated sources as multiple side information. To address this problem, we theoretically study a…

Information Theory · Computer Science 2017-01-19 Huynh Van Luong , Jurgen Seiler , Andre Kaup , Soren Forchhammer , Nikos Deligiannis

We propose an iterative algorithm for the minimization of a $\ell_1$-norm penalized least squares functional, under additional linear constraints. The algorithm is fully explicit: it uses only matrix multiplications with the three matrices…

Numerical Analysis · Mathematics 2012-02-16 Ignace Loris , Caroline Verhoeven

Normalization methods improve both optimization and generalization of ConvNets. To further boost performance, the recently-proposed switchable normalization (SN) provides a new perspective for deep learning: it learns to select different…

Computer Vision and Pattern Recognition · Computer Science 2019-03-12 Wenqi Shao , Tianjian Meng , Jingyu Li , Ruimao Zhang , Yudian Li , Xiaogang Wang , Ping Luo