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arXiv · 2609.25266

Entropy-map SSIM analysis of Salt and Pepper Noise Removal via Recursive Median Filterring

Petr Boriskov·Andrei Velichko
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Abstract

This paper studies the removal of salt-and-pepper (SP) noise from grayscale images using a median filter (MF) within a recursive thresholding algorithm. Denoising performance is assessed using two complementary metrics: SSIM-Img and SSIM-Map.SSIM-Img is standard Image Quality Assessment (IQA), the conventional Structural Similarity Index (SSIM) computed between the restored and clean images. SSIM-Map is novel IQA, an SSIM-based evaluation computed between entropy maps of these images, where the maps are obtained using singular value-decomposition entropy in sliding windows. We show that SSIM-Map is more sensitive to residual impulse artifacts, blur, and local intensity transitions, and therefore complements the conventional SSIM-Img metric.

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Petr Boriskov, Andrei Velichko. 2026-09-21. Entropy-map SSIM analysis of Salt and Pepper Noise Removal via Recursive Median Filterring. https://arxiv.org/abs/2609.25266

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