Table 3 Input features to the recognition system
features | description |
|---|---|
f0 | Fundamental frequency of the voice signal |
RI(Relative Intensity) | Ratio of intensity to the maximum intensity in syllable. |
f1 | Frequency of the first formant |
f2 | Frequency of the second formant |
f3 | Frequency of the third formant |
f1/f2 | Ratio of first to second formant frequencies |
Nasality (1/(Af1-A1k)) | Reverse of the difference between amplitude of the first formant and spectral extra peak at 1 kHz |
Entropy | Approximate entropy of the voice signal |
Fractal dimension | Fractal dimension of the speech phase space |
Lyapanov exponent | Lyapanov exponent of the voice signal |
Mean energy of Wavelet coefficients | Mean energy of Wavelet coefficients in scales 7,8 and 9 |