Extraction of acoustic features and the classification of the voiceless allocates /ts/ and /t∫/ in Japanese
O. Kunisaki, Norio Higuchi, Hiroya Fujisaki · The Journal of the Acoustical Society of America · 1978
The acoustic characteristics of voiceless affricates have not been clearly determined. The voiceless affricates /ts/ and /t∫/ in CV syllables are analyzed in this paper to obtain acoustic features useful for their discrimination from the voiceless fricatives /s/ and /∫/ as well as for distinguishing between /ts/ and /t∫/ themselves. The maximum rate of increase in short-term power at consonantal onset was found to be useful for separating the affricates from the fricatives, while the frequency of the spectral zero, extracted by assuming a model with one zero and two poles for the frequency spectrum up to 7 kHz, was found to be effective for separating the two affricates [H. Fujisaki and O. Kunisaki, IEEE Trans. ASSP-26, 21–27 (1978)]. Based on these results, a recognition test was carried out on 100 CV syllables consisting of /ts/, /t∫/, /s/, or /∫/ followed by one of the five Japanese vowels uttered by a male speaker, and a recognition rate of 99% was achieved. [Work supported by Ministry of Education Grant-in-Aid for Scientific Research No. 239005.]