Majorization-minimization generalized Krylov subspace methods for lp-lq optimization applied to image restoration
نویسندگان
چکیده
A new majorization-minimization framework for lp-lq image restoration is presented. The solution is sought in a generalized Krylov subspace that is build up during the solution process. Proof of convergence to a stationary point of the minimized lp-lq functional is provided for both convex and nonconvex problems. Computed examples illustrate that high-quality restorations can be determined with a modest number of iterations and that the storage requirement of the method is not very large. A comparison with related methods shows the competitiveness of the method proposed.
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