Review on remote heart rate measurements using photoplethysmography

Remote photoplethysmography (rPPG) gains recent great interest due to its potential in contactless heart rate measurement using consumer-level cameras. This paper presents a detailed review of rPPG measurement using computer vision and deep learning techniques for heart rate estimation. Several common gaps and difficulties of rPPG development are highlighted for the feasibility study in real-world applications. Numerous computer vision and deep learning methods are reviewed to mitigate crucial issues such as motion artifact and illumination variation. In comparison, deep learning approaches are proven more accurate than conventional computer vision methods due to their adaptive pattern learning and generalization characteristics. An increasing trend of applying deep learning techniques in rPPG can improve effective heart rate estimation and artifact removal. To consider more realistic disturbances into account, additional vital signs and large training datasets are crucial to improve the accuracy of heart rate estimations. By taking the benefit of contactless and accurate estimation, the application of rPPG can be greatly adopted in real-world activities, especially in precision sports.