{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,29]],"date-time":"2026-05-29T11:19:04Z","timestamp":1780053544985,"version":"3.54.0"},"reference-count":32,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2021,12,14]],"date-time":"2021-12-14T00:00:00Z","timestamp":1639440000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Camera-based remote photoplethysmography (rPPG) is a low-cost and casual non-contact heart rate measurement method suitable for telemedicine. Several factors affect the accuracy of measuring the heart rate and heart rate variability (HRV) using rPPG despite HRV being an important indicator for healthcare monitoring. This study aimed to investigate the appropriate setup for precise HRV measurements using rPPG while considering the effects of possible factors including illumination, direction of the light, frame rate of the camera, and body motion. In the lighting conditions experiment, the smallest mean absolute R\u2013R interval (RRI) error was obtained when light greater than 500 lux was cast from the front (among the following conditions\u2014illuminance: 100, 300, 500, and 700 lux; directions: front, top, and front and top). In addition, the RRI and HRV were measured with sufficient accuracy at frame rates above 30 fps. The accuracy of the HRV measurement was greatly reduced when the body motion was not constrained; thus, it is necessary to limit the body motion, especially the head motion, in an actual telemedicine situation. The results of this study can act as guidelines for setting up the shooting environment and camera settings for rPPG use in telemedicine.<\/jats:p>","DOI":"10.3390\/s21248357","type":"journal-article","created":{"date-parts":[[2021,12,14]],"date-time":"2021-12-14T22:06:10Z","timestamp":1639519570000},"page":"8357","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["Evaluation of Remote Photoplethysmography Measurement Conditions toward Telemedicine Applications"],"prefix":"10.3390","volume":"21","author":[{"given":"Akito","family":"Tohma","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, Tokyo University of Science, Tokyo 162-8601, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maho","family":"Nishikawa","sequence":"additional","affiliation":[{"name":"Graduate School of Informatics and Engineering, The University of Electro-Communications, Tokyo 182-0033, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7190-8233","authenticated-orcid":false,"given":"Takuya","family":"Hashimoto","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Tokyo University of Science, Tokyo 162-8601, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoichi","family":"Yamazaki","sequence":"additional","affiliation":[{"name":"Department of Home Electronics, Kanagawa Institute of Technology, Kanagawa 243-0292, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5639-3171","authenticated-orcid":false,"given":"Guanghao","family":"Sun","sequence":"additional","affiliation":[{"name":"Graduate School of Informatics and Engineering, The University of Electro-Communications, Tokyo 182-0033, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e000530","DOI":"10.1136\/fmch-2020-000530","article-title":"Telemedicine, the current COVID-19 pandemic and the future: A narrative review and perspectives moving forward in the USA","volume":"8","author":"Kichloo","year":"2020","journal-title":"Fam. 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