Researching the possibilities of remote photoplethysmography application to analysis of time-frequency changes of human heart rate variability

In the paper, possibilities of using remote photoplethysmography (rPPG) to investigation time-frequency changes of heart rate variability are discussed. The blood volume pulse rate estimated from the rPPG rhythmogram and cardiac pulse rate estimated from the electrocardiogram are compared by means of the correlation analysis. The results showed that oscillations of the rPPG rhythmogram in the very low frequency band [0.04-0.003] Hz can be used to assess functional changes of a human. For the low frequency band [0.15-0.04] Hz, the results must be verified by additional parameters such as changes of facial expression. It was concluded that the rPPG may be applied to analysis of functional reserves and adaptation level of a human.