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arXiv · 1711.07568

On Nearest Neighbors in Non Local Means Denoising

Iuri Frosio·Jan Kautz
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Abstract

To denoise a reference patch, the Non-Local-Means denoising filter processes a set of neighbor patches. Few Nearest Neighbors (NN) are used to limit the computational burden of the algorithm. Here here we show analytically that the NN approach introduces a bias in the denoised patch, and we propose a different neighbors' collection criterion, named Statistical NN (SNN), to alleviate this issue. Our approach outperforms the traditional one in case of both white and colored noise: fewer SNNs generate images of higher quality, at a lower computational cost.

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Iuri Frosio, Jan Kautz. 2017-11-20. On Nearest Neighbors in Non Local Means Denoising. https://arxiv.org/abs/1711.07568

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