Extraction of Photoplethysmography Signal For Heart Rate Estimation Using Smartphone Camera

‘Photoplethysmography’ (PPG) is an approach that uses light to monitor changes in blood mass within tissues due to systole and diastole. The resulting blood volume signal can be utilized to monitor patients, aid in diagnosis, or extract other physiological data. The traditional approach to obtain ‘PPG signals' involves using of PPG sensors that include a light emitter and a photodiode. The current digital age has transformed every area of our lives. As demand for ‘Smartphone technology’ and ‘mobile apps' continue to rise, the influence and reach of mobile health (mHealth) have significantly expanded. In this study, the ‘Near Infrared’ (NIR) LED board is used to illuminate the ‘index finger’, and a ‘smartphone camera’ is used to record fingertip video. ‘PPG signals' are derived from recorded video. From the extracted ‘PPG signal’, heart rate is estimated. The obtained results are contrasted with the readings from the ‘MEDTECH OG05 pulse oximeter'. The results of this study indicate a strong correlation between heart rate measurements derived from the PPG wave and those recorded by the ‘MEDTECH OG05 oximeter’, reflected by a ‘Pearson correlation coefficient’ of 0.88.