5. The method of claim 4 , wherein extracting the second-order scatter features from the acoustic input signal further comprises passing at least a portion of the acoustic input signal through a second wavelet transform.
5. The method of claim 4 , wherein extracting the second-order scatter features from the acoustic input signal further comprises passing at least a portion of the acoustic input signal through a second wavelet transform. 8. The method of claim 5 , wherein the extracting step is performed in the frequency domain.