Sixth International Conference on Spoken Language Processing

A new cepstrumbased technique is developed in order to provide an alternative means of estimating the harmonicstonoise ratio in voice signals. The geometric mean harmonicstonoise ratio (GHNR) is defined as the mean of the individual spectral (i.e. at specific frequency locations) harmonicstonoise ratios in dB. A heuristic development of the method treats the harmonic spectrum (in dB) of voiced speech taken over several cycles of the waveform as a more usual time domain signal, which is Fourier transformed. The sum of the resulting cepstral peaks (rahmonics) gives a direct estimation of the geometric mean harmonicstonoise ratio (GHNR). The need for, inverse Fourier transform of the masked cepstrum back into the frequency domain, baseline correction and the usual harmonicstonoise ratio (HNR) calculation is avoided by this approach. The technique is examined using synthetically generated voice signals.
Bibliographic reference. Murphy, Peter J. (2000): "A cepstrumbased harmonicstonoise ratio in voice signals", In ICSLP2000, vol.4, 672675.