{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:54:16Z","timestamp":1760147656588,"version":"build-2065373602"},"reference-count":43,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,2,17]],"date-time":"2023-02-17T00:00:00Z","timestamp":1676592000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Computers"],"abstract":"<jats:p>Smartphones, today, come equipped with a wide variety of sensors and high-speed processors that can capture, process, store, and communicate different types of data. Coupled with their ubiquity in recent years, these devices show potential as practical and portable healthcare monitors that are both cost-effective and accessible. To this end, this study focuses on examining the feasibility of smartphones in estimating the heart rate (HR), using video recordings of the users\u2019 fingerprints. The proposed methodology involves two-stage processing that combines channel-intensity-based approaches (Channel-Intensity mode\/Counter method) and a novel technique that relies on the spatial and temporal position of the recorded fingerprint edges (Edge-Detection mode). The dataset used here included 32 fingerprint video recordings taken from 6 subjects, using the rear camera of 2 smartphone models. Each video clip was first validated to determine whether it was suitable for Channel-Intensity mode or Edge-Detection mode, followed by further processing and heart rate estimation in the selected mode. The relative accuracy for recordings via the Edge-Detection mode was 93.04%, with a standard error of estimates (SEE) of 6.55 and Pearson\u2019s correlation r &gt; 0.91, while the Channel-Intensity mode showed a relative accuracy of 92.75%, with an SEE of 5.95 and a Pearson\u2019s correlation r &gt; 0.95. Further statistical analysis was also carried out using Pearson\u2019s correlation test and the Bland\u2013Altman method to verify the statistical significance of the results. The results thus show that the proposed methodology, through smartphones, is a potential alternative to existing technologies for monitoring a person\u2019s heart rate.<\/jats:p>","DOI":"10.3390\/computers12020043","type":"journal-article","created":{"date-parts":[[2023,2,20]],"date-time":"2023-02-20T04:28:57Z","timestamp":1676867337000},"page":"43","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Channel Intensity and Edge-Based Estimation of Heart Rate via Smartphone Recordings"],"prefix":"10.3390","volume":"12","author":[{"given":"Anusha","family":"Krishnamoorthy","sequence":"first","affiliation":[{"name":"Department of Biomedical Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9710-2289","authenticated-orcid":false,"given":"G. Muralidhar","family":"Bairy","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3026-4838","authenticated-orcid":false,"given":"Nandish","family":"Siddeshappa","sequence":"additional","affiliation":[{"name":"Manipal School of Information Science, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8655-4922","authenticated-orcid":false,"given":"Hilda","family":"Mayrose","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3345-360X","authenticated-orcid":false,"given":"Niranjana","family":"Sampathila","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9459-8423","authenticated-orcid":false,"given":"Krishnaraj","family":"Chadaga","sequence":"additional","affiliation":[{"name":"Department of Computer Science and Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"169","DOI":"10.2991\/jegh.k.201217.001","article-title":"Epidemiology and the Magnitude of Coronary Artery Disease and Acute Coronary Syndrome: A Narrative Review","volume":"11","author":"Ralapanawa","year":"2021","journal-title":"J. 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