{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T10:55:58Z","timestamp":1768820158600,"version":"3.49.0"},"reference-count":32,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,5,22]],"date-time":"2025-05-22T00:00:00Z","timestamp":1747872000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"PRR\u2014Plano de Recupera\u00e7\u00e3o e Resili\u00eancia under the Next Generation EU from the European Union","award":["C644919832-00000035|Project n\u00b0 46"],"award-info":[{"award-number":["C644919832-00000035|Project n\u00b0 46"]}]},{"name":"PRR\u2014Plano de Recupera\u00e7\u00e3o e Resili\u00eancia under the Next Generation EU from the European Union","award":["UID 00481"],"award-info":[{"award-number":["UID 00481"]}]},{"name":"Mechanical Technology and Automation (TEMA)","award":["C644919832-00000035|Project n\u00b0 46"],"award-info":[{"award-number":["C644919832-00000035|Project n\u00b0 46"]}]},{"name":"Mechanical Technology and Automation (TEMA)","award":["UID 00481"],"award-info":[{"award-number":["UID 00481"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper proposes an automated system integrating infrared thermography (IRT) and computer vision for air leak detection and localization in end-of-line (EOL) testing stations. This system consists of (1) a leak tester for detection and quantification of leaks, (2) an infrared camera for real-time thermal image acquisition; and (3) an algorithm for automatic leak localization. The python-based algorithm acquires thermal frames from the camera\u2019s streaming video, identifies potential leak regions by selecting a region of interest, mitigates environmental interferences via image processing, and pinpoints leaks by employing pixel intensity thresholding. A closed circuit with an embedded leak system simulated relevant leakage scenarios, varying leak apertures (ranging from 0.25 to 3 mm), and camera\u2013leak system distances (0.2 and 1 m). Results confirmed that (1) the leak tester effectively detected and quantified leaks, with larger apertures generating higher leak rates; (2) the IRT performance was highly dependent on leak aperture and camera\u2013leak system distance, confirming that shorter distances improve localization accuracy; and (3) the algorithm localized all leaks in both lab and industrial environments, regardless of the camera\u2013leak system distance, mostly achieving accuracies higher than 0.7. Overall, the combined system demonstrated great potential for long-term implementation in EOL leakage stations in the manufacturing sector, offering an effective and cost-effective alternative for manual inspections.<\/jats:p>","DOI":"10.3390\/s25113272","type":"journal-article","created":{"date-parts":[[2025,5,22]],"date-time":"2025-05-22T12:15:43Z","timestamp":1747916143000},"page":"3272","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Combining Infrared Thermography with Computer Vision Towards Automatic Detection and Localization of Air Leaks"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4149-3804","authenticated-orcid":false,"given":"\u00c2ngela","family":"Semitela","sequence":"first","affiliation":[{"name":"Centre of Mechanical Technology and Automation (TEMA), Department of Mechanical Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"Intelligent Systems Associate Laboratory (LASI), 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-9457-0532","authenticated-orcid":false,"given":"Jo\u00e3o","family":"Silva","sequence":"additional","affiliation":[{"name":"Centre of Mechanical Technology and Automation (TEMA), Department of Mechanical Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"Intelligent Systems Associate Laboratory (LASI), 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7282-885X","authenticated-orcid":false,"given":"Andr\u00e9 F.","family":"Gir\u00e3o","sequence":"additional","affiliation":[{"name":"Centre of Mechanical Technology and Automation (TEMA), Department of Mechanical Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"Intelligent Systems Associate Laboratory (LASI), 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-2081-6632","authenticated-orcid":false,"given":"Samuel","family":"Verdasca","sequence":"additional","affiliation":[{"name":"Centre of Mechanical Technology and Automation (TEMA), Department of Mechanical Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"Intelligent Systems Associate Laboratory (LASI), 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8983-9202","authenticated-orcid":false,"given":"Rita","family":"Futre","sequence":"additional","affiliation":[{"name":"Bosch Thermotechnology, S.A., Cacia, 3800-627 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0513-158X","authenticated-orcid":false,"given":"Nuno","family":"Lau","sequence":"additional","affiliation":[{"name":"Intelligent Systems Associate Laboratory (LASI), 4800-058 Guimar\u00e3es, Portugal"},{"name":"Institute of Electronics and Informatics Engineering of Aveiro (IEETA), Department of Electronics, Telecommunications and Informatics, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0417-8167","authenticated-orcid":false,"given":"Jos\u00e9 P.","family":"Santos","sequence":"additional","affiliation":[{"name":"Centre of Mechanical Technology and Automation (TEMA), Department of Mechanical Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"Intelligent Systems Associate Laboratory (LASI), 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3972-8432","authenticated-orcid":false,"given":"Ant\u00f3nio","family":"Completo","sequence":"additional","affiliation":[{"name":"Centre of Mechanical Technology and Automation (TEMA), Department of Mechanical Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"Intelligent Systems Associate Laboratory (LASI), 4800-058 Guimar\u00e3es, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Grzechca, W. 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