{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T16:30:14Z","timestamp":1772814614791,"version":"3.50.1"},"reference-count":64,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2016,5,13]],"date-time":"2016-05-13T00:00:00Z","timestamp":1463097600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"EU COST","award":["TD1202"],"award-info":[{"award-number":["TD1202"]}]},{"name":"EU COST","award":["IC1203"],"award-info":[{"award-number":["IC1203"]}]},{"DOI":"10.13039\/100017325","name":"ERC","doi-asserted-by":"publisher","award":["617754"],"award-info":[{"award-number":["617754"]}],"id":[{"id":"10.13039\/100017325","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJGI"],"abstract":"<jats:p>Geo-tagged photographs are used increasingly as a source of Volunteered Geographic Information (VGI), which could potentially be used for land use and land cover applications. The purpose of this paper is to analyze the feasibility of using this source of spatial information for three use cases related to land cover: Calibration, validation and verification. We first provide an inventory of the metadata that are collected with geo-tagged photographs and then consider what elements would be essential, desirable, or unnecessary for the aforementioned use cases. Geo-tagged photographs were then extracted from Flickr, Panoramio and Geograph for an area of London, UK, and classified based on their usefulness for land cover mapping including an analysis of the accompanying metadata. Finally, we discuss protocols for geo-tagged photographs for use of VGI in relation to land cover applications.<\/jats:p>","DOI":"10.3390\/ijgi5050064","type":"journal-article","created":{"date-parts":[[2016,5,13]],"date-time":"2016-05-13T11:53:16Z","timestamp":1463140396000},"page":"64","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":58,"title":["Investigating the Feasibility of Geo-Tagged Photographs as Sources of Land Cover Input Data"],"prefix":"10.3390","volume":"5","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7365-9995","authenticated-orcid":false,"given":"Vyron","family":"Antoniou","sequence":"first","affiliation":[{"name":"Hellenic Military Academy, Leof. Varis-Koropiou, 16673 Athens, Greece"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9408-8100","authenticated-orcid":false,"given":"Cid\u00e1lia","family":"Fonte","sequence":"additional","affiliation":[{"name":"Department of Mathematics, University of Coimbra\u2014INESC Coimbra, Coimbra, Rua Antero de Quental, n\u00b0 199 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2665-7065","authenticated-orcid":false,"given":"Linda","family":"See","sequence":"additional","affiliation":[{"name":"International Institute for Applied Systems Analysis (IIASA), Schlossplatz 1, 2361 Laxenburg, Austria"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8837-4637","authenticated-orcid":false,"given":"Jacinto","family":"Estima","sequence":"additional","affiliation":[{"name":"NOVA IMS, Universidade Nova de Lisboa (UNL), 1070-312 Lisboa, Portugal"}]},{"given":"Jamal","family":"Arsanjani","sequence":"additional","affiliation":[{"name":"GIScience Research Group, Institute of Geography, University of Heidelberg, Berliner Strasse 48, 69120 Heidelberg, Germany"},{"name":"Department of Planning and Development, Aalborg University Copenhagen, A.C. Meyers V\u00e6nge 15, DK-2450 Copenhagen, Denmark"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8379-9713","authenticated-orcid":false,"given":"Flavio","family":"Lupia","sequence":"additional","affiliation":[{"name":"Council for Agricultural Research and Economics (CREA), Via Po, 14 00198 Roma, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9993-1072","authenticated-orcid":false,"given":"Marco","family":"Minghini","sequence":"additional","affiliation":[{"name":"Politecnico di Milano, Department of Civil and Environmental Engineering, Como Campus, Via Valleggio 11, 22100 Como, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6464-3054","authenticated-orcid":false,"given":"Giles","family":"Foody","sequence":"additional","affiliation":[{"name":"School of Geography, University of Nottingham, NG7 2RD Nottingham, UK"}]},{"given":"Steffen","family":"Fritz","sequence":"additional","affiliation":[{"name":"International Institute for Applied Systems Analysis (IIASA), Schlossplatz 1, 2361 Laxenburg, Austria"}]}],"member":"1968","published-online":{"date-parts":[[2016,5,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"211","DOI":"10.1007\/s10708-007-9111-y","article-title":"Citizens as sensors: The world of volunteered geography","volume":"69","author":"Goodchild","year":"2007","journal-title":"GeoJournal"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Jokar Arsanjani, J., Zipf, A., Mooney, P., and Helbich, M. 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