Pitch determination considering laryngealization effects in spoken dialogs

A frequent phenomenon in spoken dialogs of the information seeking type are short elliptic utterances whose mood (declarative or interrogative) can only be distinguished by intonation. The main acoustic evidence is conveyed by the fundamental frequency or F_0-contour. Many algorithms for F_0 determination have been reported in the literature. A common problem are irregularities of speech known as 'laryngealizations'. This article describes an approach based on neural network techniques for the improved determination of fundamental frequency. First, an improved version of our neural network algorithm for reconstruction of the voice source signal (glottis signal) is presented. Second, the reconstructed voice source signal is used as input to another neural network distinguishing the three classes 'voiceless', 'voiced non-laryngealized', and 'voiced laryngealized'. Third, the results are used to improve an existing F_0 algorithm. Results of this approach are presented and discussed in the context of the application in a spoken dialog system. (orig.)SIGLEAvailable from TIB Hannover: RR 5221(33)+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman

Prosodic modules for speech recognition and understanding in VERBMOBIL

Within Verbmobil, a large project on spoken language research in Germany, two modules for detecting and recognizing prosodic events have been developed. One module operates on speech signal parameters and the word hypothesis graph, whereas the other module, designed for a novel, highly interactive architecture, only uses speech signal parameters as its input. Phrase boundaries, sentence moduality, and accents are detected. The recognition rates in spontaneous dialogs are for accents up to 82.5%, for phrase boundaries up to 91.7%. (orig.)Available from TIB Hannover: RR 5221(148)+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman