{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,4]],"date-time":"2026-04-04T11:30:58Z","timestamp":1775302258721,"version":"3.50.1"},"reference-count":54,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,7,24]],"date-time":"2025-07-24T00:00:00Z","timestamp":1753315200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Natural Science Foundation of China","award":["62002208"],"award-info":[{"award-number":["62002208"]}]},{"name":"Natural Science Foundation of China","award":["42271093"],"award-info":[{"award-number":["42271093"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Multi-focus image fusion (MFIF) is an image-processing method that aims to generate fully focused images by integrating source images from different focal planes. However, the defocus spread effect (DSE) often leads to blurred or jagged focus\/defocus boundaries in fused images, which affects the quality of the image. To address this issue, this paper proposes a novel model that embeds the Kolmogorov\u2013Arnold network with convolutional layers in parallel within the U-Net architecture (KCUNet). This model keeps the spatial dimensions of the feature map constant to maintain high-resolution details while progressively increasing the number of channels to capture multi-level features at the encoding stage. In addition, KCUNet incorporates a content-guided attention mechanism to enhance edge information processing, which is crucial for DSE reduction and edge preservation. The model\u2019s performance is optimized through a hybrid loss function that evaluates in several aspects, including edge alignment, mask prediction, and image quality. Finally, comparative evaluations against 15 state-of-the-art methods demonstrate KCUNet\u2019s superior performance in both qualitative and quantitative analyses.<\/jats:p>","DOI":"10.3390\/e27080785","type":"journal-article","created":{"date-parts":[[2025,7,24]],"date-time":"2025-07-24T15:19:22Z","timestamp":1753370362000},"page":"785","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["KCUNET: Multi-Focus Image Fusion via the Parallel Integration of KAN and Convolutional Layers"],"prefix":"10.3390","volume":"27","author":[{"given":"Jing","family":"Fang","sequence":"first","affiliation":[{"name":"School of Physics and Electronics, Shandong Normal University, Jinan 250358, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ruxian","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Physics and Electronics, Shandong Normal University, Jinan 250358, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xinglin","family":"Ning","sequence":"additional","affiliation":[{"name":"School of Physics and Electronics, Shandong Normal University, Jinan 250358, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ruiqing","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Physics and Electronics, Shandong Normal University, Jinan 250358, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6071-963X","authenticated-orcid":false,"given":"Shuyun","family":"Teng","sequence":"additional","affiliation":[{"name":"School of Physics and Electronics, Shandong Normal University, Jinan 250358, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xuran","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Physics and Electronics, Shandong Normal University, Jinan 250358, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhipeng","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Physics and Electronics, Shandong Normal University, Jinan 250358, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wenfeng","family":"Lu","sequence":"additional","affiliation":[{"name":"School of Management Engineering, Shandong Jianzhu University, Jinan 250101, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shaohai","family":"Hu","sequence":"additional","affiliation":[{"name":"Institute of Information Science, Beijing Jiaotong University, Beijing 100044, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1597-1793","authenticated-orcid":false,"given":"Jingjing","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Physics and Electronics, Shandong Normal University, Jinan 250358, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,24]]},"reference":[{"key":"ref_1","first-page":"4819","article-title":"Deep learning-based multi-focus image fusion: A survey and a comparative study","volume":"44","author":"Zhang","year":"2021","journal-title":"IEEE Trans. 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