A Short Note for Nonlocal TV Minimization
نویسنده
چکیده
This is a short note to explain how to efficiently minimize the nonlocal Total Variation (NLTV) energy. The method is based on the Split-Bregman (SB), introduced by Goldstein-Osher in [8], and extended to a nonlocal/graph version by Zhang-Burger-Bresson-Osher in [13]. For the 256 × 256 Barbara picture, the computation of weights takes around 1 second for a patch size 5 × 5 and a search window 11 × 11 and the NLTV minimization takes less 2 seconds. So, the total time for an image 256× 256 for the NLTV minimization is less than 3 seconds. For the 512 × 512 Barbara picture, patch 5×5, window search 13×13, the weight computation takes 7 seconds and the NLTV minimization 8 seconds. We also compare the SB version of NLTV with the dual version of NLTV, the NLH, and the NL-Means. Experiments show that the SB-NLTV provides the best denoising result.
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