Table 3.
Description of features extracted from the cardiac cycles detected from the photoplethysmograms.
| Feature | Description (Units of Measurement) |
|---|---|
| F1 | Cycle duration, measured from consecutive TI points (s) |
| F2 | Pulse amplitude, measured as the amplitude difference between the onset of the pulse and its systolic peak (V) |
| F3 | Amplitude of the maximum slope point, measured from the onset of the pulse (V) |
| F4 | Area of the pulse, measured from consecutive TI points (V) |
| F5 | Area of the systolic phase, measured from the onset of the pulse and the location of the systolic peak (V) |
| F6 | Area of the diastolic phase, measured from the location of the systolic peak and the onset of the next pulse (V) |
| F7 | x-coordinate of the centroid of the pulse (s) |
| F8 | y-coordinate of the centroid of the pulse (V) |
| F9 | x-coordinate of the centroid of the systolic phase of the pulse (s) |
| F10 | y-coordinate of the centroid of the systolic phase of the pulse (V) |
| F11 | x-coordinate of the centroid of the diastolic phase of the pulse (s) |
| F12 | y-coordinate of the centroid of the diastolic phase of the pulse (V) |
| F13 | Pulse width, measured as the difference between F9 and F11 (s) |
| F14 | Rise time, measured as the time between the onset of the pulse and the location of the systolic peak (s) |
| F15 | Decay time, measured as the time between the location of the systolic peak and the onset of the next pulse (s) |
| F16 | Upslope angle, measured as the inverse tangent of the triangle formed by F2 and F14 (rad) |
| F17 | Downslope angle, measured as the inverse tangent of the triangle formed by F2 and F15 (rad) |