{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,24]],"date-time":"2026-07-24T20:16:51Z","timestamp":1784924211301,"version":"3.55.0"},"reference-count":39,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2023,3,22]],"date-time":"2023-03-22T00:00:00Z","timestamp":1679443200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Spanish Government","award":["MCIN\/AEI\/10.1303501100011033"],"award-info":[{"award-number":["MCIN\/AEI\/10.1303501100011033"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Along with society\u2019s development, transportation has become a key factor in human daily life, increasing the number of vehicles on the streets. Consequently, the task of finding free parking slots in metropolitan areas can be dramatically challenging, increasing the chance of getting involved in an accident and the carbon footprint, and negatively affecting the driver\u2019s health. Therefore, technological resources to deal with parking management and real-time monitoring have become key players in this scenario to speed up the parking process in urban areas. This work proposes a new computer-vision-based system that detects vacant parking spaces in challenging situations using color imagery processed by a novel deep-learning algorithm. This is based on a multi-branch output neural network that maximizes the contextual image information to infer the occupancy of every parking space. Every output infers the occupancy of a specific parking slot using all the input image information, unlike existing approaches, which only use a neighborhood around every slot. This allows it to be very robust to changing illumination conditions, different camera perspectives, and mutual occlusions between parked cars. An extensive evaluation has been performed using several public datasets, proving that the proposed system outperforms existing approaches.<\/jats:p>","DOI":"10.3390\/s23063329","type":"journal-article","created":{"date-parts":[[2023,3,22]],"date-time":"2023-03-22T06:35:28Z","timestamp":1679466928000},"page":"3329","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Visual Parking Occupancy Detection Using Extended Contextual Image Information via a Multi-Branch Output ConvNeXt Network"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5534-3487","authenticated-orcid":false,"given":"Leyre","family":"Enc\u00edo","sequence":"first","affiliation":[{"name":"Grupo de Tratamiento de Im\u00e1genes (GTI), Information Processing and Telecommunications Center, Universidad Polit\u00e9cnica de Madrid, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2030-9390","authenticated-orcid":false,"given":"C\u00e9sar","family":"D\u00edaz","sequence":"additional","affiliation":[{"name":"Grupo de Tratamiento de Im\u00e1genes (GTI), Information Processing and Telecommunications Center, Universidad Polit\u00e9cnica de Madrid, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0618-3488","authenticated-orcid":false,"given":"Carlos R.","family":"del-Blanco","sequence":"additional","affiliation":[{"name":"Grupo de Tratamiento de Im\u00e1genes (GTI), Information Processing and Telecommunications Center, Universidad Polit\u00e9cnica de Madrid, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6449-5151","authenticated-orcid":false,"given":"Fernando","family":"Jaureguizar","sequence":"additional","affiliation":[{"name":"Grupo de Tratamiento de Im\u00e1genes (GTI), Information Processing and Telecommunications Center, Universidad Polit\u00e9cnica de Madrid, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0397-894X","authenticated-orcid":false,"given":"Narciso","family":"Garc\u00eda","sequence":"additional","affiliation":[{"name":"Grupo de Tratamiento de Im\u00e1genes (GTI), Information Processing and Telecommunications Center, Universidad Polit\u00e9cnica de Madrid, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,22]]},"reference":[{"key":"ref_1","unstructured":"Direcci\u00f3n General de Carreteras (2021). 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