Algorithm 1 CalcFeatures_stft function

1:procedure CalcFeatures_stft($x,fs\_custom,window=‘\mathrm{hamming}’,nperseg=32,noverlap=0$) 2:    $(f,t,Zxx)\leftarrow \mathrm{STFT}(x,fs=fs\_custom,window=window,nperseg=nperseg,noverlap=noverlap)$ 3:    $z\leftarrow \mathrm{abs}\left(Zxx\right)$ 4:    $n\leftarrow \mathrm{number}\mathrm{of}\mathrm{rows}\left(z\right)$ 5:    $m\leftarrow \mathrm{number}\mathrm{of}\mathrm{columns}\left(z\right)$   6:     Calculate statistical features for each row of z: $y1\leftarrow \mathrm{mean}(z,axis=1)$ $y2\leftarrow \max (z,axis=1)$ $y3\leftarrow \mathrm{RMS}(z,axis=1)$ $y4\leftarrow \mathrm{std}(z,axis=1)$ $y5\leftarrow \mathrm{std}(z,axis=1)/\mathrm{mean}(z,axis=1)$ $y6\leftarrow \max (z,axis=1)/\mathrm{mean}(z,axis=1)$   7:    $\mathit{features}\leftarrow \mathrm{concatenate}(y1,y2,y3,y4,y5,y6,axis=0)$ 8:    return $\mathit{features}$ 9:end procedure