The Sliding Frank-Wolfe Algorithm for the BLASSO
Q. Denoyelle, V. Duval, G. Peyré, E. Soubies
Proceedings of the Workshop on Signal Processing with Adaptive Sparse Structured Representations (SPARS'19), Toulouse, French Republic, July 1-4, 2019, paper no. 172.
This paper showcases the Sliding Frank-Wolfe (SFW), which is a novel optimization algorithm to solve the BLASSO sparse spikes super-resolution problem. The BLASSO is the continuous (i.e. off-thegrid or grid-less) counterpart of the well-known ℓ1 sparse regularisation method (also known as LASSO or Basis Pursuit). Our algorithm is a variation on the classical Frank-Wolfe (also known as conditional gradient) which follows a recent trend of interleaving convex optimization updates (corresponding to adding new spikes) with non-convex optimization steps (corresponding to moving the spikes). We prove theoretically that this algorithm terminates in a finite number of steps under a mild non-degeneracy hypothesis.
@INPROCEEDINGS(http://bigwww.epfl.ch/publications/denoyelle1901.html, AUTHOR="Denoyelle, Q. and Duval, V. and Peyr{\'{e}}, G. and Soubies, E.", TITLE="The Sliding {F}rank-{W}olfe Algorithm for the {BLASSO}", BOOKTITLE="Proceedings of the Workshop on Signal Processing with Adaptive Sparse Structured Representations ({SPARS'19})", YEAR="2019", editor="", volume="", series="", pages="", address="Toulouse, French Republic", month="July 1-4,", organization="", publisher="", note="paper no.\ 172")