Search Results for author: Raj Rao Nadakuditi

Found 14 papers, 2 papers with code

Sparse Equisigned PCA: Algorithms and Performance Bounds in the Noisy Rank-1 Setting

no code implementations22 May 2019 Arvind Prasadan, Raj Rao Nadakuditi, Debashis Paul

Singular value decomposition (SVD) based principal component analysis (PCA) breaks down in the high-dimensional and limited sample size regime below a certain critical eigen-SNR that depends on the dimensionality of the system and the number of samples.

Free Component Analysis: Theory, Algorithms & Applications

no code implementations5 May 2019 Hao Wu, Raj Rao Nadakuditi

We describe a method for unmixing mixtures of freely independent random variables in a manner analogous to the independent component analysis (ICA) based method for unmixing independent random variables from their additive mixtures.

Time Series Source Separation using Dynamic Mode Decomposition

1 code implementation4 Mar 2019 Arvind Prasadan, Raj Rao Nadakuditi

We show that when the latent time series are uncorrelated at a lag of one time-step then, in the large sample limit, the recovered dynamic modes will approximate, up to a column-wise normalization, the columns of the mixing matrix.

blind source separation Change Point Detection +2

Online Adaptive Image Reconstruction (OnAIR) Using Dictionary Models

no code implementations6 Sep 2018 Brian E. Moore, Saiprasad Ravishankar, Raj Rao Nadakuditi, Jeffrey A. Fessler

Sparsity and low-rank models have been popular for reconstructing images and videos from limited or corrupted measurements.

Denoising Image Reconstruction +1

Panoramic Robust PCA for Foreground-Background Separation on Noisy, Free-Motion Camera Video

no code implementations18 Dec 2017 Brian E. Moore, Chen Gao, Raj Rao Nadakuditi

We perform extensive numerical experiments on both static and moving camera video subject to a variety of dense and sparse corruptions.

Robust Photometric Stereo via Dictionary Learning

no code implementations24 Oct 2017 Andrew J. Wagenmaker, Brian E. Moore, Raj Rao Nadakuditi

We propose a model that applies dictionary learning to regularize and reconstruct the normal vectors from the images under the classic Lambertian reflectance model.

Dictionary Learning

Robust Surface Reconstruction from Gradients via Adaptive Dictionary Regularization

no code implementations30 Sep 2017 Andrew J. Wagenmaker, Brian E. Moore, Raj Rao Nadakuditi

This paper introduces a novel approach to robust surface reconstruction from photometric stereo normal vector maps that is particularly well-suited for reconstructing surfaces from noisy gradients.

Dictionary Learning Surface Reconstruction

Robust Photometric Stereo Using Learned Image and Gradient Dictionaries

no code implementations30 Sep 2017 Andrew J. Wagenmaker, Brian E. Moore, Raj Rao Nadakuditi

Photometric stereo is a method for estimating the normal vectors of an object from images of the object under varying lighting conditions.

Dictionary Learning

Augmented Robust PCA For Foreground-Background Separation on Noisy, Moving Camera Video

no code implementations27 Sep 2017 Chen Gao, Brian E. Moore, Raj Rao Nadakuditi

This work presents a novel approach for robust PCA with total variation regularization for foreground-background separation and denoising on noisy, moving camera video.

Denoising

Low-rank and Adaptive Sparse Signal (LASSI) Models for Highly Accelerated Dynamic Imaging

no code implementations13 Nov 2016 Saiprasad Ravishankar, Brian E. Moore, Raj Rao Nadakuditi, Jeffrey A. Fessler

For example, the patches of the underlying data are modeled as sparse in an adaptive dictionary domain, and the resulting image and dictionary estimation from undersampled measurements is called dictionary-blind compressed sensing, or the dynamic image sequence is modeled as a sum of low-rank and sparse (in some transform domain) components (L+S model) that are estimated from limited measurements.

Image Reconstruction

Efficient Sum of Outer Products Dictionary Learning (SOUP-DIL) and Its Application to Inverse Problems

1 code implementation19 Nov 2015 Saiprasad Ravishankar, Raj Rao Nadakuditi, Jeffrey A. Fessler

This paper exploits the ideas that drive algorithms such as K-SVD, and investigates in detail efficient methods for aggregate sparsity penalized dictionary learning by first approximating the data with a sum of sparse rank-one matrices (outer products) and then using a block coordinate descent approach to estimate the unknowns.

Denoising Dictionary Learning +1

OptShrink: An algorithm for improved low-rank signal matrix denoising by optimal, data-driven singular value shrinkage

no code implementations25 Jun 2013 Raj Rao Nadakuditi

The truncated singular value decomposition (SVD) of the measurement matrix is the optimal solution to the_representation_ problem of how to best approximate a noisy measurement matrix using a low-rank matrix.

Denoising

Cannot find the paper you are looking for? You can Submit a new open access paper.