{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2024,9,6]],"date-time":"2024-09-06T18:55:32Z","timestamp":1725648932072},"reference-count":38,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2021,9,21]],"date-time":"2021-09-21T00:00:00Z","timestamp":1632182400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003246","name":"Nederlandse Organisatie voor Wetenschappelijk Onderzoek","doi-asserted-by":"publisher","award":["15345"],"id":[{"id":"10.13039\/501100003246","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"Both Respiratory Flow (RF) and Respiratory Motion (RM) are visible in thermal recordings of infants. Monitoring these two signals usually requires landmark detection for the selection of a region of interest. Other approaches combine respiratory signals coming from both RF and RM, obtaining a Mixed Respiratory (MR) signal. The detection and classification of apneas, particularly common in preterm infants with low birth weight, would benefit from monitoring both RF and RM, or MR, signals. Therefore, we propose in this work an automatic RF pixel detector not based on facial\/body landmarks. The method is based on the property of RF pixels in thermal videos, which are in areas with a smooth circular gradient. We defined 5 features combined with the use of a bank of Gabor filters that together allow selection of the RF pixels. The algorithm was tested on thermal recordings of 9 infants amounting to a total of 132 min acquired in a neonatal ward. On average the percentage of correctly identified RF pixels was 84%. Obstructive Apneas (OAs) were simulated as a proof of concept to prove the advantage in monitoring the RF signal compared to the MR signal. The sensitivity in the simulated OA detection improved for the RF signal reaching 73% against the 23% of the MR signal. Overall, the method yielded promising results, although the positioning and number of cameras used could be further optimized for optimal RF visibility.<\/jats:p>","DOI":"10.3390\/s21186306","type":"journal-article","created":{"date-parts":[[2021,9,22]],"date-time":"2021-09-22T02:35:20Z","timestamp":1632278120000},"page":"6306","source":"Crossref","is-referenced-by-count":8,"title":["Automatic Separation of Respiratory Flow from Motion in Thermal Videos for Infant Apnea Detection"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"http:\/\/orcid.org\/0000-0002-1479-2446","authenticated-orcid":false,"given":"Ilde","family":"Lorato","sequence":"first","affiliation":[{"name":"Department of Electrical Engineering, Eindhoven University of Technology, 5612 AZ Eindhoven, The Netherlands"}]},{"ORCID":"http:\/\/orcid.org\/0000-0002-2518-6847","authenticated-orcid":false,"given":"Sander","family":"Stuijk","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Eindhoven University of Technology, 5612 AZ Eindhoven, The Netherlands"}]},{"given":"Mohammed","family":"Meftah","sequence":"additional","affiliation":[{"name":"Department of Family Care Solutions, Philips Research, 5656 AE Eindhoven, The Netherlands"}]},{"given":"Deedee","family":"Kommers","sequence":"additional","affiliation":[{"name":"Department of Neonatology, M\u00e1xima Medical Centre, 5504 DB Veldhoven, The Netherlands"},{"name":"Department of Applied Physics, Eindhoven University of Technology, 5612 AZ Eindhoven, The Netherlands"}]},{"ORCID":"http:\/\/orcid.org\/0000-0002-5159-6874","authenticated-orcid":false,"given":"Peter","family":"Andriessen","sequence":"additional","affiliation":[{"name":"Department of Neonatology, M\u00e1xima Medical Centre, 5504 DB Veldhoven, The Netherlands"},{"name":"Department of Applied Physics, Eindhoven University of Technology, 5612 AZ Eindhoven, The Netherlands"}]},{"ORCID":"http:\/\/orcid.org\/0000-0001-7342-9623","authenticated-orcid":false,"given":"Carola","family":"van Pul","sequence":"additional","affiliation":[{"name":"Department of Applied Physics, Eindhoven University of Technology, 5612 AZ Eindhoven, The Netherlands"},{"name":"Department of Clinical Physics, M\u00e1xima Medical Centre, 5504 DB Veldhoven, The Netherlands"}]},{"given":"Gerard","family":"de Haan","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Eindhoven University of Technology, 5612 AZ Eindhoven, The Netherlands"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,21]]},"reference":[{"key":"ref_1","first-page":"494","article-title":"Respiratory Rate: The Forgotten Vital Sign\u2014Make It Count!","volume":"44","author":"Loughlin","year":"2018","journal-title":"Jt. 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