Abstract: In an acoustic noise suppressor, a power spectrum component and a phase component are extracted from an input signal by a frequency analysis part, while at the same time a check is made in a speech/non-speech identification part to see if the input signal is a speech signal or noise. Only when the input signal is noise, its spectrum is stored in a storage part and is weighted by a psychoacoustic weighting function W(f), and the weighted spectrum is subtracted from the power spectrum of the input signal and is reconverted to a time-domain signal by making its inverse analysis.

Abstract: In a waveform compilation (waveform concatenation or synthesis-by-rule) type speech synthesis method and speech synthesizer, phoneme waveform segments in natural speech waveforms are clustered, and one of the phoneme waveform segments having a parameter nearest the centroid of LPC parameters of all the phoneme waveforms in each cluster is selected and stored as a representative phoneme waveform in a waveform information memory. When synthesizing a speech waveform, representative phoneme waveforms of the same phonemes, whose context is most similar to that of each phoneme of a phoneme string of the speech to be synthesized, are selectively read out of the waveform information memory and thus read-out representative phoneme waveforms are sequentially concatenated for output as a continuous synthesized speech waveform.