{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:20:18Z","timestamp":1760242818085,"version":"build-2065373602"},"reference-count":22,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2016,11,25]],"date-time":"2016-11-25T00:00:00Z","timestamp":1480032000000},"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>We propose the visualization of venous compliance (VC) using a digital red-green-blue (RGB) camera. The new imaging method, which transforms RGB values into VC, combines VC evaluation with blood concentration estimation from the RGB values of each pixel. We evaluate a non-contact plethysmography (NCPG) system for VC based on comparisons with conventional strain gauge plethysmography (SPG). We conduct in vivo measurements using both systems and investigate their differences by evaluating the VC. The results show that the two methods measure different blood vessels and that errors caused by interstitial fluid accumulation are negligible for the NCPG system, whereas SPG is influenced by such errors. Additionally, we investigate the relationship between VC and physical activity using NCPG.<\/jats:p>","DOI":"10.3390\/s16121996","type":"journal-article","created":{"date-parts":[[2016,11,25]],"date-time":"2016-11-25T08:18:15Z","timestamp":1480061895000},"page":"1996","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Visualization of Venous Compliance of Superficial Veins Using Non-Contact Plethysmography Based on Digital Red-Green-Blue Images"],"prefix":"10.3390","volume":"16","author":[{"given":"Kazuya","family":"Nakano","sequence":"first","affiliation":[{"name":"Faculty of Science, Division 2, Tokyo University of Science, 1-3, Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan"}]},{"given":"Yuta","family":"Aoki","sequence":"additional","affiliation":[{"name":"Graduate School of Bio-Application and Systems Engineering, Tokyo University of Agriculture and Technology, 2-24-16, Naka-cho, Koganei, Tokyo 184-8588, Japan"}]},{"given":"Ryota","family":"Satoh","sequence":"additional","affiliation":[{"name":"Graduate School of Bio-Application and Systems Engineering, Tokyo University of Agriculture and Technology, 2-24-16, Naka-cho, Koganei, Tokyo 184-8588, Japan"}]},{"given":"Hiroyuki","family":"Suzuki","sequence":"additional","affiliation":[{"name":"Laboratory for Future Interdisciplinary Research of Science and Technology, Institute of Innovative Research, Tokyo Institute of Technology, 4259, Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8503, Japan"}]},{"given":"Izumi","family":"Nishidate","sequence":"additional","affiliation":[{"name":"Graduate School of Bio-Application and Systems Engineering, Tokyo University of Agriculture and Technology, 2-24-16, Naka-cho, Koganei, Tokyo 184-8588, Japan"}]}],"member":"1968","published-online":{"date-parts":[[2016,11,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1034","DOI":"10.1007\/s10439-005-5763-2","article-title":"Contactless multiple wavelength photoplethysmographic imaging: A first step toward \u201cSpO2 camera\u201d technology","volume":"33","author":"Wieringa","year":"2005","journal-title":"Ann. Biomed. Eng."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"McCombie, D.B., Shaltis, P.A., Reisner, A.T., and Asada, H.H. (2007, January 23\u201326). Adaptive hydrostatic blood pressure calibration: Development of a wearable, autonomous pulse wave velocity blood pressure monitor. Proceedings of the 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, Lyon, France.","DOI":"10.1109\/IEMBS.2007.4352301"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"044304","DOI":"10.1063\/1.2724789","article-title":"Noncontact simultaneous dual wavelength photoplethysmography: A further step toward noncontact pulse oximetry","volume":"78","author":"Humphreys","year":"2007","journal-title":"Rev. Sci. 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[11th ed.]."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/16\/12\/1996\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T19:27:26Z","timestamp":1760210846000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/16\/12\/1996"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2016,11,25]]},"references-count":22,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2016,12]]}},"alternative-id":["s16121996"],"URL":"https:\/\/doi.org\/10.3390\/s16121996","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2016,11,25]]}}}