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Related papers: Quality Versus Sparsity in Image Recovery by Dicti…

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Dictionary learning, the problem of recovering a sparsely used matrix $\mathbf{D} \in \mathbb{R}^{M \times K}$ and $N$ $s$-sparse vectors $\mathbf{x}_i \in \mathbb{R}^{K}$ from samples of the form $\mathbf{y}_i = \mathbf{D}\mathbf{x}_i$, is…

Machine Learning · Computer Science 2023-03-29 Alexei Novikov , Stephen White

This paper tackles algorithmic and theoretical aspects of dictionary learning from incomplete and random block-wise image measurements and the performance of the adaptive dictionary for sparse image recovery. This problem is related to…

Computer Vision and Pattern Recognition · Computer Science 2015-08-04 Mohammad Aghagolzadeh , Hayder Radha

In this paper we consider the dictionary learning problem for sparse representation. We first show that this problem is NP-hard by polynomial time reduction of the densest cut problem. Then, using successive convex approximation strategies,…

Machine Learning · Computer Science 2015-11-06 Meisam Razaviyayn , Hung-Wei Tseng , Zhi-Quan Luo

Sparse sampling schemes have the potential to dramatically reduce image acquisition time while simultaneously reducing radiation damage to samples. However, for a sparse sampling scheme to be useful it is important that we are able to…

Computer Vision and Pattern Recognition · Computer Science 2017-03-16 G. M. Dilshan P. Godaliyadda , Dong Hye Ye , Michael D. Uchic , Michael A. Groeber , Gregery T. Buzzard , Charles A. Bouman

The sparsity of signals in a transform domain or dictionary has been exploited in applications such as compression, denoising and inverse problems. More recently, data-driven adaptation of synthesis dictionaries has shown promise compared…

Machine Learning · Computer Science 2019-06-14 Saiprasad Ravishankar , Raj Rao Nadakuditi , Jeffrey A. Fessler

Subspace clustering techniques have shown promise in hyperspectral image segmentation. The fundamental assumption in subspace clustering is that the samples belonging to different clusters/segments lie in separable subspaces. What if this…

Computer Vision and Pattern Recognition · Computer Science 2021-11-30 Anurag Goel , Angshul Majumdar

Sparse representation using over-complete dictionaries have shown to produce good quality results in various image processing tasks. Dictionary learning algorithms have made it possible to engineer data adaptive dictionaries which have…

Image and Video Processing · Electrical Eng. & Systems 2019-11-11 Nishant Deepak Keni , Amol Mangirish Singbal , Rizwan Ahmed

Sparse coding or sparse dictionary learning has been widely used to recover underlying structure in many kinds of natural data. Here, we provide conditions guaranteeing when this recovery is universal; that is, when sparse codes and…

Neurons and Cognition · Quantitative Biology 2016-11-18 Christopher J. Hillar , Friedrich T. Sommer

Blind image restoration is a non-convex problem which involves restoration of images from an unknown blur kernel. The factors affecting the performance of this restoration are how much prior information about an image and a blur kernel are…

Computer Vision and Pattern Recognition · Computer Science 2015-12-15 Chia-Chen Lee , Wen-Liang Hwang

Sparse representations using learned dictionaries are being increasingly used with success in several data processing and machine learning applications. The availability of abundant training data necessitates the development of efficient,…

Computer Vision and Pattern Recognition · Computer Science 2013-09-26 Jayaraman J. Thiagarajan , Karthikeyan Natesan Ramamurthy , Andreas Spanias

Recently, great attention was intended toward overcomplete dictionaries and the sparse representations they can provide. In a wide variety of signal processing problems, sparsity serves a crucial property leading to high performance.…

Multimedia · Computer Science 2008-12-15 SeyyedMajid Valiollahzadeh , Mohammad Nazari , Massoud Babaie-Zadeh , Christian Jutten

Top-k sparsification has recently been widely used to reduce the communication volume in distributed deep learning. However, due to the Sparse Gradient Accumulation (SGA) dilemma, the performance of top-k sparsification still has…

Machine Learning · Computer Science 2024-02-26 Minjun Zhao , Yichen Yin , Yuren Mao , Qing Liu , Lu Chen , Yunjun Gao

The power of sparse signal modeling with learned over-complete dictionaries has been demonstrated in a variety of applications and fields, from signal processing to statistical inference and machine learning. However, the statistical…

Information Theory · Computer Science 2017-04-26 Ignacio Ramírez , Guillermo Sapiro

Deep neural networks have emerged as powerful tools for learning operators defined over infinite-dimensional function spaces. However, existing theories frequently encounter difficulties related to dimensionality and limited…

Machine Learning · Computer Science 2026-05-12 Jianfei Li , Shuo Huang , Han Feng , Ding-Xuan Zhou , Gitta Kutyniok

We consider the problem of learning overcomplete dictionaries in the context of sparse coding, where each sample selects a sparse subset of dictionary elements. Our main result is a strategy to approximately recover the unknown dictionary…

Machine Learning · Statistics 2014-07-08 Alekh Agarwal , Animashree Anandkumar , Praneeth Netrapalli

Learned Sparse Retrieval (LSR) is a group of neural methods designed to encode queries and documents into sparse lexical vectors. These vectors can be efficiently indexed and retrieved using an inverted index. While LSR has shown promise in…

Information Retrieval · Computer Science 2024-02-13 Thong Nguyen , Mariya Hendriksen , Andrew Yates

Sparse Representation (SR) of signals or data has a well founded theory with rigorous mathematical error bounds and proofs. SR of a signal is given by superposition of very few columns of a matrix called Dictionary, implicitly reducing…

Computer Vision and Pattern Recognition · Computer Science 2026-04-01 G. Madhuri , Atul Negi

Sparse coding in learned dictionaries has been established as a successful approach for signal denoising, source separation and solving inverse problems in general. A dictionary learning method adapts an initial dictionary to a particular…

Machine Learning · Statistics 2012-10-18 Christian D. Sigg , Tomas Dikk , Joachim M. Buhmann

Image enhancement is an important image processing technique that processes images suitably for a specific application e.g. image editing. The conventional solutions of image enhancement are grouped into two categories which are spatial…

Computer Vision and Pattern Recognition · Computer Science 2016-09-14 Hui Li , Xiaomeng Wang , Weifeng Liu , Yanjiang Wang

Dictionary learning and sparse representation (DLSR) is a recent and successful mathematical model for data representation that achieves state-of-the-art performance in various fields such as pattern recognition, machine learning, computer…

Computer Vision and Pattern Recognition · Computer Science 2015-02-23 Mehrdad J. Gangeh , Ahmed K. Farahat , Ali Ghodsi , Mohamed S. Kamel