“…The segments Ω k , k = 1,2, … , K are derived using slope sum function. First the PPG signal is filtered with narrow band pass filter and the filtered PPG is slope-adjusted and realigned through weighted slope sum function [1] to find the series of Ω k , k = 1,2, … , K, where K is the total number of complete heart cycles present in P s . Let , = 1,2, … , K be the segment length of Ω k .…”