Riccardo Rossetti
INFOCOM Dept., Univ. of Rome ``La Sapienza,'' via Eudossiana 18, 00184 Rome, Italy
An acoustic study of geminated and nongerminated Italian stops was carried out. The analysis was performed on 648 VCV syllables, where V is one of the vowels [i, a, u] and C is one of the consonants [p, t, k, b, d, g] (in geminated and nongeminated form). The syllables were uttered by 6 speakers, 3 repetitions. The analysis of the segments durations corresponding to the different articulatory phases of the VCV structure showed a strong correlation between the presence of gemination and the first vowel and occlusive silence durations. Statistical analyses using an a posteriori classifier yielded to a classification score of 96.1%. An analysis of the properties of the burst (energy, power, and spectral shape) showed that there is no correlation between these and the presence of gemination. An automatic software system, which allows the modification of a single/geminated VCV utterance into a geminated/single one, was developed. Informal perceptual tests, in which the stimuli were obtained by using the previous program, validated the significance of the first vowel and the occlusion durations as acoustic correlates of gemination.