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arXiv · 1502.05037

Why CLEAN when you can PURIFY? A new approach for next-generation radio-interferometric imaging

Rafael E. Carrillo·Jason D. McEwen·Yves Wiaux
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Abstract

In recent works, sparse models and convex optimization techniques have been applied to radio-interferometric (RI) imaging showing the potential to outperform state-of-the-art imaging algorithms in the field. In this talk, I will review our latest contributions in RI imaging, which leverage the versatility of convex optimization to both handle realistic continuous visibilities and offer a highly parallelizable structure paving the way to high-dimensional data scalability. Firstly, I will review our recently proposed average sparsity approach, SARA, which relies on the observation that natural images exhibit strong average sparsity over multiple coherent bases. Secondly, I will discuss efficient implementations of SARA, and sparse regularization problems in general, for large-scale imaging problems in a new toolbox dubbed

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Rafael E. Carrillo, Jason D. McEwen, Yves Wiaux. 2015-02-17. Why CLEAN when you can PURIFY? A new approach for next-generation radio-interferometric imaging. https://arxiv.org/abs/1502.05037

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