[Statistical study of laryngeal frequency. Application to the analysis and synthesis of prosodic features of French].

Some precisions concerning the specification and the instruments developed for the measurement of laryngeal frequency F1 being stated, the authors give statistical results for French. In first approximation, the F1 distribution is gaussian for a given corpus; the standard deviation measured and given in percentage referring to the mean laryngeal frequency F1 is about 16% for male and female speakers. Ceteris partibus, the variations of F1 are relatively low for a given speaker from one record to an other (about +/- 1/2 tone). The means of F1 are given for samples (gaussian) concerning adults (30 males and 30 female): respectively 118 and 207 Hz with standard deviation sigma (F1) of 18 and 20 Hz. The ratio tau 1 of the voiced duration to the total duration of the corpus, dependant on the sex: 0.50 for men and 0.63 for women (the difference is significant at the 0.001 level) allows the specification of the speaking rate. When the speaking rate increases, the length of pauses decreases. These results can be used for an estimation of the precision of the statistical measurement of F1 and sigma (F1), in relation to the number of periods N. To N appears a total duration of the corpus determined by tau 1. A comparison is made between the results of the calculation and the measurement. The F1 specification can be used for determination of the vocal source of synthesizer to improve naturalness of synthetic sounds and for analysis and synthesis of prosodic features using the results of two previous papers which have allowed to specify the position of level 1, 2 and 4 and to show the differences in the perceptual importance of the variations introduced in connection with the three levels.