ML	Machine Learning
HMD	Head-Mounted Display
ROI	Region of Interest
FFT	Fast Fourier Transform
CNN	Convolutional Neural Network
RMSE	Root Mean Square Error
MAPE	Mean Absolute Percentage Error
LSTM	Long Short-Term Memory
SVM	Support Vector Machine
BPM	Beat Per Minute
PPG	PhotoPlethysmoGraphy
rPPG	Remote PhotoPlethysmoGraphy
EVM	Eulerian Video Magnification
ME	Mean Error
SD	Standard Deviation
$\rho$	Pearson’s correlation