Table 1.

Some of the most widely used features as discussed in [34].

Type	Features	Some Applications
Time-domain	Mean [35], variance, standard deviation [36,37], root mean square [38,39], zero or mean crossing rate [40], derivative, peak counts [41,42]	Human activity recognition [37,38], speech recognition [39], eye movement analysis [42]
Frequency-domain	Discrete fast Fourier transforms coefficient, spectral energy [7,43]	Human activity recognition [7]
Time frequency domain	Wavelet coefficients [44]	Blink detection [42]