{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,29]],"date-time":"2026-08-29T05:18:32Z","timestamp":1787980712883,"version":"build-2784847793"},"reference-count":27,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T00:00:00Z","timestamp":1787788800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["62571239"],"award-info":[{"award-number":["62571239"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"award":["62571239"],"award-info":[{"award-number":["62571239"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/100016804","name":"Shenzhen Natural Science Foundation","doi-asserted-by":"crossref","award":["JCYJ20250604190734042"],"award-info":[{"award-number":["JCYJ20250604190734042"]}],"id":[{"id":"10.13039\/100016804","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100001809","name":"Joint Fund of the National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["U2441285"],"award-info":[{"award-number":["U2441285"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"award":["U2441285"],"award-info":[{"award-number":["U2441285"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Experimental Technology Research and Development Project of Nanjing University of Aeronautics and Astronautics","award":["SYJS202604Z"],"award-info":[{"award-number":["SYJS202604Z"]}]},{"award":["SYJS202604Z"],"award-info":[{"award-number":["SYJS202604Z"]}],"id":[{"id":"https:\/\/ror.org\/01scyh794","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>\u03b3-photon tomography provides a non-contact approach for reconstructing and visualizing flow-field parameters. However, the resulting grayscale images often exhibit blurred boundaries and weak texture features, causing conventional colorization methods such as DeOldify to produce cross-region color diffusion and boundary color overflow. To address this, this paper proposes a \u03b3-photon flow-field image colorization algorithm based on the Hybrid Swin Colorization Network (HSCN). A hybrid dual-stream encoder composed of a Swin Transformer semantic stream and a central difference convolution (CDC) gradient branch is combined with cross-stage gradient injection and a spatially gated adaptive fusion mechanism to enhance the perception of high-frequency structures at flow-field boundaries and suppress color overflow. The effectiveness of the algorithm is evaluated in terms of colorization quality and flow-field temperature-parameter inversion using \u03b3-photon flow-field images of two CFD-simulated flow patterns, a large-scale vortical wake and a horizontal wake. The proposed method achieves PSNR, SSIM, FID, and MAE values of 38.7422, 0.9372, 10.7344, and 0.0085, respectively. Compared with DeOldify, PSNR and SSIM are improved by 24.30% and 11.89%, while FID and MAE are reduced by 42.98% and 60.47%, respectively. In addition, HSCN achieved a MAPE of 12.65% across 15 boundary and temperature-transition locations in three representative samples, compared with 31.24% for DeOldify and 28.70% for DDColor.<\/jats:p>","DOI":"10.3390\/e28090959","type":"journal-article","created":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T09:00:35Z","timestamp":1787821235000},"page":"959","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Colorization Algorithm for \u03b3-Photon Flow Field Images Based on the HSCN Model"],"prefix":"10.3390","volume":"28","author":[{"given":"Hui","family":"Xiao","sequence":"first","affiliation":[{"name":"College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, 29 Jiangjun Road, Nanjing 211106, China"},{"name":"Shenzhen Research Institute, Nanjing University of Aeronautics and Astronautics, Shenzhen 518110, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Liying","family":"Hou","sequence":"additional","affiliation":[{"name":"College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, 29 Jiangjun Road, Nanjing 211106, China"},{"name":"Shenzhen Research Institute, Nanjing University of Aeronautics and Astronautics, Shenzhen 518110, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiantang","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, 29 Jiangjun Road, Nanjing 211106, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"103704","DOI":"10.1063\/1.2795648","article-title":"High resolution gamma ray tomography scanner for flow measurement and non-destructive testing applications","volume":"78","author":"Hampel","year":"2007","journal-title":"Rev. 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