Study on PPG Biometric Recognition Based on Multifeature Extraction and Naive Bayes Classifier

Table 2

Calculation formula of the time-domain feature (TDF) of a sample.

Label of the feature	Name of the feature	Formula
	Max value
	Min value
	Peak value (PV)
	Peak to peak value
	Mean value
	Square root amplitude (SRA)
	Mean amplitude (MA)
	Variance
	Standard deviation (STD)
	Root mean square (RMS)
	Skewness
	Kurtosis
	Waveform index
	Pulse index
	Peak index
	Margin index
	Clearance index