Representation Learning via Cauchy Convolutional Sparse Coding
- URL: http://arxiv.org/abs/2008.03473v1
- Date: Sat, 8 Aug 2020 08:21:44 GMT
- Title: Representation Learning via Cauchy Convolutional Sparse Coding
- Authors: Perla Mayo, Oktay Karaku\c{s}, Robin Holmes and Alin Achim
- Abstract summary: Convolutional Sparse Coding (CSC) enables unsupervised learning of features by jointly optimising both an (ell)-norm fidelity term and a sparsity enforcing penalty.
This work investigates using a regularisation term derived from an assumed Cauchy prior for the coefficients of the feature maps of a CSC generative model.
The sparsity penalty term resulting from this prior is solved via its proximal operator, which is then applied iteratively, element-wise, on the coefficients of the feature maps to optimise the CSC cost function.
- Score: 7.784354802855044
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: In representation learning, Convolutional Sparse Coding (CSC) enables
unsupervised learning of features by jointly optimising both an \(\ell_2\)-norm
fidelity term and a sparsity enforcing penalty. This work investigates using a
regularisation term derived from an assumed Cauchy prior for the coefficients
of the feature maps of a CSC generative model. The sparsity penalty term
resulting from this prior is solved via its proximal operator, which is then
applied iteratively, element-wise, on the coefficients of the feature maps to
optimise the CSC cost function. The performance of the proposed Iterative
Cauchy Thresholding (ICT) algorithm in reconstructing natural images is
compared against the common choice of \(\ell_1\)-norm optimised via soft and
hard thresholding. ICT outperforms IHT and IST in most of these reconstruction
experiments across various datasets, with an average PSNR of up to 11.30 and
7.04 above ISTA and IHT respectively.
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