摘要 |
In an analysis-by-synthesis speech coder employing a short-term perceptual weighting filter with transfer function W(z)=A(z/.gamma.1)/A(z/.gamma.2), the values of the spectral expansion coefficients .gamma.1 and .gamma.2 are adapted dynamically on the basis of spectral parameters obtained during short-term linear prediction analysis. The spectral parameters serving in this adaptation may in particular comprise parameters representative of the overall slope of the spectrum of the speech signal, and parameters representative of the resonant character of the short-term synthesis filter. |