• Corpus ID: 239616552

Block based refitting in $\ell_{12}$ sparse regularisation

@inproceedings{Deledalle2019BlockBR,
  title={Block based refitting in \$\ell\_\{12\}\$ sparse regularisation},
  author={Charles-Alban Deledalle and Nicolas Papadakis and Joseph Salmon and Samuel Vaiter},
  year={2019}
}
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 `12 block based regularization. While efficient at retrieving the inherent sparsity patterns of the data – the support – the estimated solutions are known to suffer from a systematical bias. We propose a general framework for removing this artifact by refitting the solution… 

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