Title
Adaptive structured block sparsity via dyadic partitioning
Abstract
This paper proposes a novel method to adapt the block-sparsity structure to the observed noisy data. Towards this goal, the Stein risk estimator framework is exploited, and the block-sparsity is dyadically organized in a tree. The adaptation of the sparsity structure is obtained by finding the best recursive dyadic partition, whose terminal nodes (leaves) are the blocks, that minimizes a data-driven estimator of the risk. Our main contributions are (i) analytical expression of the risk; (ii) a novel estimator of the risk; (iii) a fast algorithm that yields the best partition. Numerical results on wavelet-domain denoising of synthetic and natural images illustrate the improvement brought by our adaptive approach.
Year
Venue
Keywords
2011
Barcelona
image denoising,wavelet transforms,stein risk estimator framework,adaptive structured block sparsity,best recursive dyadic partition,wavelet-domain denoising,estimation,noise reduction,noise measurement
Field
DocType
ISSN
Noise reduction,Noisy data,Mathematical optimization,Noise measurement,Algorithm,Partition (number theory),Mathematics,Recursion,Estimator
Conference
2076-1465
Citations 
PageRank 
References 
4
0.50
9
Authors
3
Name
Order
Citations
PageRank
Gabriel Peyré1119579.60
Jalal Fadili2118480.08
Christophe Chesneau362.26