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This paper proposes an approach for people counting that is based on the use of cameras and Raspberry Pi platforms, together with an edge-based transfer learning framework that is enriched with specific image processing strategies, with the aim of this approach being adopted in different indoor environments without the need for tailored training phases. The system was deployed on a university campus, which was chosen as the case study. The proposed system was able to work in classrooms with different characteristics. This paper reports a proposed architecture that could make the system scalable and privacy compliant and the evaluation tests that were conducted in different types of classrooms, which demonstrate the feasibility of this approach. Overall, the system was able to count the number of people in classrooms with a maximum mean absolute error of 1.23.<\/jats:p>","DOI":"10.3390\/s22103692","type":"journal-article","created":{"date-parts":[[2022,5,12]],"date-time":"2022-05-12T23:08:36Z","timestamp":1652396916000},"page":"3692","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["Edge-Based Transfer Learning for Classroom Occupancy Detection in a Smart Campus Context"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2087-0535","authenticated-orcid":false,"given":"Lorenzo","family":"Monti","sequence":"first","affiliation":[{"name":"INAF\u2014Istituto di Radioastronomia, 40127 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rita","family":"Tse","sequence":"additional","affiliation":[{"name":"Faculty of Applied Sciences, Macao Polytechnic University, Macao, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8104-7887","authenticated-orcid":false,"given":"Su-Kit","family":"Tang","sequence":"additional","affiliation":[{"name":"Faculty of Applied Sciences, Macao Polytechnic University, Macao, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5385-4734","authenticated-orcid":false,"given":"Silvia","family":"Mirri","sequence":"additional","affiliation":[{"name":"Department of Computer Science and Engineering, University of Bologna, 40126 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6640-5746","authenticated-orcid":false,"given":"Giovanni","family":"Delnevo","sequence":"additional","affiliation":[{"name":"Department of Computer Science and Engineering, University of Bologna, 40126 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1220-1235","authenticated-orcid":false,"given":"Vittorio","family":"Maniezzo","sequence":"additional","affiliation":[{"name":"Department of Computer Science and Engineering, University of Bologna, 40126 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1717-1901","authenticated-orcid":false,"given":"Paola","family":"Salomoni","sequence":"additional","affiliation":[{"name":"Department of Computer Science and Engineering, University of Bologna, 40126 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,5,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"295","DOI":"10.1016\/j.jss.2018.06.035","article-title":"Supporting end users to control their smart home: Design implications from a literature review and an empirical investigation","volume":"144","author":"Caivano","year":"2018","journal-title":"J. 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