SURE-Based Projections Onto Convex Sets for Image Restoration
نویسندگان
چکیده
Projections onto convex sets (POCS) algorithms have been widely used for image restoration problem. However, the relaxation parameter (l ) of POCS is strongly data-dependent and difficult to tune. In this work we focus on optimally selecting such parameter in POCS algorithm for image restoration. A stein’s unbiased risk estimate (SURE) based POCS (SPOCS) for image restoration algorithm is proposed, in which SURE is used to determine an optimal value. Finally, the effectiveness of the optimality of the proposed parameter selection is tested by image restoration experiments. Streszczenie. W artykule przedstawiono metodę optymalnego doboru parametru relaksacji dla algorytmu POCS, służącego do odtwarzania obrazów. W proponowanym rozwiązaniu (SPOCS) zastosowano estymator Stein’a (SURE), służący do wyznaczenia optymalnej wartości współczynnika lambda. Działania algorytmu zostało zbadane eksperymentalnie. (Zastosowanie estymatora SURE w metodzie POCS do odtwarzania obrazów).
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