TITLE:
Two Modifications of Weight Calculation of the Non-Local Means Denoising Method
AUTHORS:
Musab Elkheir Salih, Xuming Zhang, Mingyue Ding
KEYWORDS:
Non-Local Means; Singular Value Decomposition; Weight Calculation
JOURNAL NAME:
Engineering,
Vol.5 No.10B,
December
20,
2013
ABSTRACT: The non-local
means (NLM) denoising method replaces each pixel by the weighted average of
pixels with the sur-rounding neighborhoods. In this paper we employ a cosine
weighting function instead of the original exponential func-tion to
improve the efficiency of the NLM denoising method. The cosine function
outperforms in the high level noise more than low level noise. To increase the
performance more in the low level noise we calculate the neighborhood si-milarity
weights in a lower-dimensional subspace using singular value decomposition (SVD).
Experimental compari-sons between the proposed modifications against the
original NLM algorithm demonstrate its superior denoising per-formance in
terms of peak signal to noise ratio (PSNR) and histogram, using various test
images corrupted by additive white Gaussian noise (AWGN).