{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:14:02Z","timestamp":1760145242129,"version":"build-2065373602"},"reference-count":30,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2024,6,28]],"date-time":"2024-06-28T00:00:00Z","timestamp":1719532800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Council of Humanities, Sciences, and Technologies (CONAHCYT)","award":["A1-S-43214"],"award-info":[{"award-number":["A1-S-43214"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This study rigorously investigates the effectiveness of nonlinear filters in CMOS for 2-D signal processing to enhance image quality. We comprehensively compare traditional linear filters\u2019 performance, which operate on the principle of linearity, with nonlinear filters, such as the median-median (Med-Med) approach, designed to handle nonlinear data. To ensure the validity of our findings, we use widely accepted metrics like normalized squared error (NSE), peak signal-to-noise ratio (PSNR), and structural similarity index (SSIM) to quantify the differences. Our simulations and experiments, conducted under controlled conditions, demonstrate that nonlinear filters in CMOS outperform linear filters in removing impulse noise and enhancing images. We also address the challenges of implementing these algorithms at the hardware level, focusing on power consumption and chip area optimization. Additionally, we propose a new architecture for the Med-Med filter and validate its functionality through experiments using a 9-pixel image sensor array. Our findings highlight the potential of nonlinear filters in CMOS for real-time image quality enhancement and their applicability in various real-world imaging applications. This research contributes to visual technology by combining theoretical insights with practical implementations, paving the way for more efficient and adaptable imaging systems.<\/jats:p>","DOI":"10.3390\/s24134213","type":"journal-article","created":{"date-parts":[[2024,7,1]],"date-time":"2024-07-01T10:14:46Z","timestamp":1719828886000},"page":"4213","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Exploring the Efficacy of Nonlinear Filters in CMOS for 2-D Signal Processing for Image Quality Enhancement"],"prefix":"10.3390","volume":"24","author":[{"given":"Hector","family":"Bandala-Hernandez","sequence":"first","affiliation":[{"name":"National Institute for Astrophysics, Optics and Electr\u00f3nics, Luis Enrique Erro #1, Sta Mar\u00eda Tonanzintla, Puebla 72840, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8336-1068","authenticated-orcid":false,"given":"Alejandro","family":"Bautista-Castillo","sequence":"additional","affiliation":[{"name":"National Institute for Astrophysics, Optics and Electr\u00f3nics, Luis Enrique Erro #1, Sta Mar\u00eda Tonanzintla, Puebla 72840, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3694-2468","authenticated-orcid":false,"given":"Jos\u00e9 Miguel","family":"Rocha-P\u00e9rez","sequence":"additional","affiliation":[{"name":"National Institute for Astrophysics, Optics and Electr\u00f3nics, Luis Enrique Erro #1, Sta Mar\u00eda Tonanzintla, Puebla 72840, Mexico"},{"name":"Benem\u00e9rita Universidad Aut\u00f3noma de Puebla, Facultad de Ciencias de la Electronica, Ciudad Universitaria, Mexico City 72000, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4322-7873","authenticated-orcid":false,"given":"Victor Hugo","family":"Carbajal G\u00f3mez","sequence":"additional","affiliation":[{"name":"National Institute for Astrophysics, Optics and Electr\u00f3nics, Luis Enrique Erro #1, Sta Mar\u00eda Tonanzintla, Puebla 72840, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4529-6864","authenticated-orcid":false,"given":"Alejandro","family":"D\u00edaz-S\u00e1nchez","sequence":"additional","affiliation":[{"name":"National Institute for Astrophysics, Optics and Electr\u00f3nics, Luis Enrique Erro #1, Sta Mar\u00eda Tonanzintla, Puebla 72840, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,6,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Kim, H.J., Shrestha, A., Sapkota, E., Pokharel, A., Pandey, S., Kim, C.S., and Shrestha, R. 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