| Time Series |
---|---|
1 | Cough Length: length from the start of the cough until 99.4% of the cough energy is achieved (s) |
2 | L-ratio: Cough flow length/cough sound length |
3 | Skewness: where μ, and σ are the mean, and the standard deviation of the cough sound signal respectively. |
4 | Kurtosis: where μ, and σ are the mean, and the standard deviation of the cough sound signal respectively. |
5 | Crest Factor: maximum sound pressure wave/Root Mean Square "RMS" sound |
 | Frequency Series |
6 | Dominant Frequency: the frequency with the most power present in the cough sound pressure wave (Hz) |
7 | Total energy |
8-24 | Octave Analysis (1-17)** |
25 | Total Power: total power in the cough sound signal (W) |
26 | Peak Power: maximum power level (W) |
27 | Average Power: Average power over all frequency ranges (W) |
28 | Sound beta: the inverse power law 1/fβ of the power spectrum [22]. |
29 | Sound Wavelet: a wavelet parameter based on the variability in the wavelet detail coefficients found in the wavelet decomposition of the cough sound |
30 | Ratio: mean spectrogram intensity/max spectrogram intensity |
31 | Peaks: this counts the number of peaks in the spectrogram that meet a given threshold |
32-51 | Spec1 - Spec20: The spectrogram is broken into 20 evenly spaced time intervals. For each interval, the maximum energy is found, and the corresponding frequency is saved. |
52-81 | Spec21 - Spec50: The spectrogram is broken into 30 evenly space time intervals. For each interval, the average frequency is calculated and saved. |
82-111 | Spec51 - Spec80: The spectrogram is broken into 30 evenly spaced frequency intervals. For each frequency interval the time at which half of the energy is attained is saved. |