{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,21]],"date-time":"2026-02-21T18:27:11Z","timestamp":1771698431071,"version":"3.50.1"},"reference-count":32,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2022,11,18]],"date-time":"2022-11-18T00:00:00Z","timestamp":1668729600000},"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":"publisher","award":["62101456"],"award-info":[{"award-number":["62101456"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["62171023"],"award-info":[{"award-number":["62171023"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["622202Y040104"],"award-info":[{"award-number":["622202Y040104"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["JSSCBS20220936"],"award-info":[{"award-number":["JSSCBS20220936"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["ZXL2022459"],"award-info":[{"award-number":["ZXL2022459"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Open Fund of Science and Technology on Electromagnetic Scattering Key Laboratory","award":["62101456"],"award-info":[{"award-number":["62101456"]}]},{"name":"Open Fund of Science and Technology on Electromagnetic Scattering Key Laboratory","award":["62171023"],"award-info":[{"award-number":["62171023"]}]},{"name":"Open Fund of Science and Technology on Electromagnetic Scattering Key Laboratory","award":["622202Y040104"],"award-info":[{"award-number":["622202Y040104"]}]},{"name":"Open Fund of Science and Technology on Electromagnetic Scattering Key Laboratory","award":["JSSCBS20220936"],"award-info":[{"award-number":["JSSCBS20220936"]}]},{"name":"Open Fund of Science and Technology on Electromagnetic Scattering Key Laboratory","award":["ZXL2022459"],"award-info":[{"award-number":["ZXL2022459"]}]},{"name":"Doctoral Mass Entrepreneurship and Innovation in Jiangsu Province","award":["62101456"],"award-info":[{"award-number":["62101456"]}]},{"name":"Doctoral Mass Entrepreneurship and Innovation in Jiangsu Province","award":["62171023"],"award-info":[{"award-number":["62171023"]}]},{"name":"Doctoral Mass Entrepreneurship and Innovation in Jiangsu Province","award":["622202Y040104"],"award-info":[{"award-number":["622202Y040104"]}]},{"name":"Doctoral Mass Entrepreneurship and Innovation in Jiangsu Province","award":["JSSCBS20220936"],"award-info":[{"award-number":["JSSCBS20220936"]}]},{"name":"Doctoral Mass Entrepreneurship and Innovation in Jiangsu Province","award":["ZXL2022459"],"award-info":[{"award-number":["ZXL2022459"]}]},{"name":"2022 Suzhou innovation and entrepreneurship leading talents program","award":["62101456"],"award-info":[{"award-number":["62101456"]}]},{"name":"2022 Suzhou innovation and entrepreneurship leading talents program","award":["62171023"],"award-info":[{"award-number":["62171023"]}]},{"name":"2022 Suzhou innovation and entrepreneurship leading talents program","award":["622202Y040104"],"award-info":[{"award-number":["622202Y040104"]}]},{"name":"2022 Suzhou innovation and entrepreneurship leading talents program","award":["JSSCBS20220936"],"award-info":[{"award-number":["JSSCBS20220936"]}]},{"name":"2022 Suzhou innovation and entrepreneurship leading talents program","award":["ZXL2022459"],"award-info":[{"award-number":["ZXL2022459"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>As sea-crossing bridges are important hubs connecting separated land areas, their detection in SAR images is of great significance. However, under complex scenarios, the sea surface conditions, the distribution of coastal terrain morphologies, and the scattering components of different structures in the bridge area are very complex and diverse, which makes the accurate and robust detection of sea-crossing bridges difficult, including the sea\u2013land segmentation and bridge feature extraction on which the detection depends. In this paper, we propose a polarimetric SAR image detection method for sea-crossing bridges based on windowed level set segmentation and polarization parameter discrimination. Firstly, the sea and land are segmented by a proposed windowed level set segmentation method, which replaces the construction of the level set segmentation energy function based on the isolated pixel distribution with a joint distribution of pixels in a certain window region. Secondly, water regions of interest are extracted by a proposed water region merging algorithm combining the distances of the water contour and polarization similarity parameter. Finally, the bridge regions of interest (ROIs) are extracted by merging close water contours, and the ROIs are discriminated by the polarimetric parameters of the polarization entropy and scattering angle. Experimental results using multiple AirSAR, RADARSAT-2, and TerraSAR-X quad-polarization SAR data from the coastal areas of San Francisco in the USA, Singapore, and Fuzhou, Fujian, and Zhanjiang, Guangdong, in China show that the proposed method can achieve 100% detection of sea-crossing bridges in different bands for different scenes, and the accuracy of the intersection of the ground-truth (IoG) index of bridge body recognition can reach more than 85%. The proposed method can improve the detection rate and reduce the false alarm rate compared with the traditional spatial-based method.<\/jats:p>","DOI":"10.3390\/rs14225856","type":"journal-article","created":{"date-parts":[[2022,11,21]],"date-time":"2022-11-21T04:33:32Z","timestamp":1669005212000},"page":"5856","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Sea-Crossing Bridge Detection in Polarimetric SAR Images Based on Windowed Level Set Segmentation and Polarization Parameter Discrimination"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0669-3701","authenticated-orcid":false,"given":"Chun","family":"Liu","sequence":"first","affiliation":[{"name":"School of Software, Northwestern Polytechnical University, Xi\u2019an 710072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chao","family":"Li","sequence":"additional","affiliation":[{"name":"Science and Technology on Electromagnetic Scattering Laboratory, Beijing 100854, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jian","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering, Tsinghua University, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Liping","family":"Hu","sequence":"additional","affiliation":[{"name":"Science and Technology on Electromagnetic Scattering Laboratory, Beijing 100854, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3633","DOI":"10.1080\/01431160601024226","article-title":"Extraction of bridges over water from IKONOS panchromatic data","volume":"28","author":"Luo","year":"2007","journal-title":"Int. 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