A Generalized Krylov Subspace Method for ℓp-ℓq Minimization

نویسندگان

  • Alessandro Lanza
  • Serena Morigi
  • Lothar Reichel
  • Fiorella Sgallari
چکیده

This paper presents a new efficient approach for the solution of the lp-lq minimization problem based on the application of successive orthogonal projections onto generalized Krylov subspaces of increasing dimension. The subspaces are generated according to the iteratively reweighted least-squares strategy for the approximation of lp/lq-norms by weighted l2-norms. Computed image restoration examples illustrate that it suffices to carry out only a few iterations to achieve highquality restorations. The combination of a low iteration count and a modest storage requirement makes the proposed method attractive.

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عنوان ژورنال:
  • SIAM J. Scientific Computing

دوره 37  شماره 

صفحات  -

تاریخ انتشار 2015