Abstract:
The quantity, harmonic-to-noise ratio (HNR), has been used to estimate the level of noise in human voice signals. HNR estimation can be accomplished in two ways: (1) Time-domain techniques, in which HNR is computed directly from the acoustic waveform; and (2) frequency-domain techniques, in which HNR is computed from a transformed representation of the waveform. It is unclear, however, how to operationally relate time- and frequency-domain estimations of HNR because of the quasiperiodicity of human voice signals. This work demonstrates the relationship between time- and frequency-domain estimations of HNR experimentally. Results indicate that the time-domain estimation of HNR approximates the average levels of harmonics measured above a reference spectral envelope, which is obtained by cepstral analysis. [Work support by NIH.]