Heart rate monitoring using peak detection in photoplethysmography signals of fingertip images captured using smartphone

Abstract

Smartphone plays a major role in contributing towards preventive health care services, as they enable users to track by themselves, their diet and fitness regime. Monitoring vital signs particularly, heart rate regularly helps in early detection of heart related ailments. Given the present context, a smartphone is readily available with most of the population; hence it is much easy to monitor heart rate using the same. In this paper, a smartphone based application is presented which calculates the heart rate from the photoplethysmography (PPG) signals obtained from the fingertip images captured through the camera. Heart rate is calculated by counting the peaks that occur in the PPG signals in a particular duration. In order to detect the peaks, a peak detection algorithm proposed in [1] is used, as the algorithm helps in detecting peaks accurately without any pre-processing. The proposed technique is very simple as it calculates heart rate directly from time series PPG data without the need of converting to frequency domain data and can be employed in any smartphone to measure heart rate. In order to validate the proposed method, experiment was performed to calculate the heart rate of forty nine individuals and the obtained results were compared with heart rate readings measured using digital blood pressure (BP) monitor for those individuals. The heart rate obtained from proposed method is close to one that is obtained from digital blood pressure monitor with three percent discrepancy.