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This work identifies two key parameters\u2014tone mapping and sensor threshold\u2014that significantly impact cPPG measurements. We propose a novel calibration method to linearize camera measurements, thus enhancing consistency and transferability of cPPG across devices. A benchtop calibration system is also presented, leveraging a microcontroller and LED setup to characterize these parameters for each phone model. Our validation studies demonstrate that, with appropriate calibration and camera settings, cPPG applications can achieve 74% higher accuracy than with default settings. Moreover, our calibration method proves effective across different smartphone models (<jats:inline-formula><mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" id=\"IM1\"><mml:mi>N<\/mml:mi><mml:mo>=<\/mml:mo><mml:mn>4<\/mml:mn><\/mml:math><\/jats:inline-formula>), and calibrations performed on one phone can be applied to other smartphones of the same model (<jats:inline-formula><mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" id=\"IM2\"><mml:mi>N<\/mml:mi><mml:mo>=<\/mml:mo><mml:mn>6<\/mml:mn><\/mml:math><\/jats:inline-formula>), enhancing consistency and scalability of cPPG applications.<\/jats:p>","DOI":"10.3389\/fdgth.2023.1301019","type":"journal-article","created":{"date-parts":[[2023,11,24]],"date-time":"2023-11-24T15:23:35Z","timestamp":1700839415000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":4,"title":["A calibration method for smartphone camera photophlethysmography"],"prefix":"10.3389","volume":"5","author":[{"given":"Yinan","family":"Xuan","sequence":"first","affiliation":[]},{"given":"Colin","family":"Barry","sequence":"additional","affiliation":[]},{"given":"Nick","family":"Antipa","sequence":"additional","affiliation":[]},{"given":"Edward Jay","family":"Wang","sequence":"additional","affiliation":[]}],"member":"1965","published-online":{"date-parts":[[2023,11,24]]},"reference":[{"key":"B1","doi-asserted-by":"crossref","first-page":"203","DOI":"10.1007\/978-3-319-19656-5_29","article-title":"HeartSense: Estimating heart rate from smartphone photoplethysmogram using adaptive filter, interpolation","volume-title":"Internet of things. 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