Algorithm 2 Pseudo-Code: Deriving PPG Derivatives

Inputs: PPG

1.1.1. Initialize Bandpass Filter Parameters (Filter Order, Passband, Stopband, Sampling Frequencies)

2.1.1 bandpass_filter = designfilt(Bandpass Filter using Filter Parameters)

2.2.1 delay = mean(grpdelay(bandpass_filter))

3.1.1 Initialize Sample_Num = linspace(1, length(PPG), length(PPG))

3.2.1 dt = Sample_Num(2) − Sample_Num(1) 3.3.1 PPG = Normalize(PPG) 3.4.1 VPG = Normalize(bandpass_filter(PPG)/dt) 3.5.1 APG = Normalize(bandpass_filter(VPG)/dt) 3.6.1 PPG = PPG(1:end−2*delay) 3.7.1 VPG = VPG(delay+1:end) 3.8.1 APG = APG(2*delay+1:end) Outputs: PPG, VPG, APG