Armando Vannucci
INFOCOM Dept., Univ. of Rome ``La Sapienza,'' via Eudossiana 18, 00184 Rome, Italy
The object of this study was the determination of acoustic correlates of two distinctive features of Italian stops related to voicing and point of articulation. The analysis was carried out on 648 VCV syllables. The correlates found for voicing were the sound bar during the voiced stops occlusion and the low-frequency (LF) burst energy. Informal perceptual tests showed the relevance of only the second correlate. As to the point of articulation, the attention was focused both on formants transition from the first vowel to the following stop and on the spectral shape of the burst. For the formants transition, different groups of templates were obtained for the different vowels. The burst spectrum was then analyzed to obtain a gross representation through four centroids defining three segments with different slopes. A posteriori classification based on either voicing (sound bar and LF burst energy) or point of articulation (gross spectral shape) yielded on the previous database to a classification score of 88% and 87%, respectively. These strategies were implemented in a system used for the recognition of Italian stops in VCV structures. An inter-linguistic study aimed at comparing Italian dental stops with British English corresponding alveolars in progress.