Improvements in Speech Synthesis: Cost 258: The Naturalness of Synthetic Speech

Naturalness in synthetic speech is one of the most intractable problems in information technology today. Although speech synthesis systems have improved considerably over the last 20 years, they rarely sound entirely like human speakers. Why is this so, and what can be done about it? * Prosodic processing must be rendered more varied and more appropriate to the speech situation * Timing, melodic control and the relationships between the various prosodic parameters need increased attention * Signal processing systems must be developed and perfected that are capable of generating more than just one voice from a database * A better understanding must be achieved of what distinguishes one voice from another, and of how speech styles differ between simply reading aloud numbers and sentences and their use in interactive speech * New evaluation methodologies should be developed to provide objective and subjective measurements of the intelligibility of the synthetic speech and the cognitive load imposed upon the listener by impoverished stimuli * Adequate text markup systems must be proposed and tested with multiple languages in real-world situations * Further research is required to integrate speech synthesis systems into larger natural-language processing systems Improvements in Speech Synthesis presents the latest research in the above areas. Contributors include speech synthesis specialists from 16 countries, with experience in the development of systems for 12 European languages. This volume emerges from a four-year European COST project focussed on "The Naturalness of Synthetic Speech", and will be a valuable text for everyone involved in speech synthesis.

Table of Contents:
List of Contributors ix Preface xiii Part I Issues in Signal Generation 1 1 Towards Greater Naturalness: Future Directions of Research in Speech Synthesis 3 Eric Keller 2 Towards More Versatile Signal Generation Systems 18 GeÂrard Bailly 3 A Parametric Harmonic ‡ Noise Model 22 GeÂrard Bailly 4 The COST 258 Signal Generation Test Array 39 GeÂrard Bailly 5 Concatenative Text-to-Speech Synthesis Based on Sinusoidal Modelling 52 Eduardo RodrõÂguez Banga,Carmen GarcõÂa Mateo and Xavier FernaÂndez Salgado 6 Shape Invariant Pitch and Time-Scale Modification of Speech Based on a Harmonic Model 64 Darragh O'Brien and Alex Monaghan 7 Concatenative Speech Synthesis Using SRELP 76 Erhard Rank Part II Issues in Prosody 87 8 Prosody in Synthetic Speech: Problems, Solutions and Challenges 89 Alex Monaghan 9 State-of-the-Art Summary of European Synthetic Prosody R&D 93 Alex Monaghan 10 Modelling FO in Various Romance Languages: Implementation in Some TTS Systems 104 Philippe Martin 11 Acoustic Characterisation of the Tonic Syllable in Portuguese 120 JoaÄo Paulo Ramos Teixeira and Diamantino R.S. Freitas 12 Prosodic Parameters of Synthetic Czech: Developing Rules for Duration and Intensity 129 Marie DohalskaÂ,Jana Mejvaldova and Tomas DubeÏda 13 MFGI, a Linguistically Motivated Quantitative Model of German Prosody 134 HansjoÈrg Mixdorff 14 Improvements in Modelling the FO Contour for Different Types of Intonation Units in Slovene 144 Ales Dobnikar 15 Representing Speech Rhythm 154 Brigitte Zellner Keller and Eric Keller 16 Phonetic and Timing Considerations in a Swiss High German TTS System 165 Beat Siebenhaar,Brigitte Zellner Keller and Eric Keller 17 Corpus-based Development of Prosodic Models Across Six Languages 176 Justin Fackrell,Halewijn Vereecken,Cynthia Grover, Jean-Pierre Martens and Bert Van Coile 18 Vowel Reduction in German Read Speech 186 Christina Widera Part III Issues in Styles of Speech 197 19 Variability and Speaking Styles in Speech Synthesis 199 Jacques Terken 20 An Auditory Analysis of the Prosody of Fast and Slow Speech Styles in English, Dutch and German 204 Alex Monaghan 21 Automatic Prosody Modelling of Galician and its Application to Spanish 218 Eduardo LoÂpez Gonzalo,Juan M. Villar Navarro and Luis A. HernaÂndez GoÂmez 22 Reduction and Assimilatory Processes in Conversational French Speech: Implications for Speech Synthesis 228 Danielle Duez 23 Acoustic Patterns of Emotions 237 Branka Zei Pollermann and Marc Archinard 24 The Role of Pitch and Tempo in Spanish Emotional Speech: Towards Concatenative Synthesis 246 Juan Manuel Montero Martinez,Juana M. GutieÂrrez Arriola, Ricardo de CoÂrdoba Herralde,Emilia Victoria EnrõÂquez Carrasco and Jose Manuel Pardo MunÄoz 25 Voice Quality and the Synthesis of Affect 252 Ailbhe Nõ Chasaide and Christer Gobl 26 Prosodic Parameters of a `Fun' Speaking Style 264 Kjell Gustafson and David House 27 Dynamics of the Glottal Source Signal: Implications for Naturalness in Speech Synthesis 273 Christer Gobl and Ailbhe Nõ Chasaide 28 A Nonlinear Rhythmic Component in Various Styles of Speech 284 Brigitte Zellner Keller and Eric Keller Part IV Issues in Segmentation and Mark-up 293 29 Issues in Segmentation and Mark-up 295 Mark Huckvale 30 The Use and Potential of Extensible Mark-up �XML) in Speech Generation 297 Mark Huckvale 31 Mark-up for Speech Synthesis: A Review and Some Suggestions 307 Alex Monaghan 32 Automatic Analysis of Prosody for Multi-lingual Speech Corpora 320 Daniel Hirst 33 Automatic Speech Segmentation Based on Alignment with a Text-to-Speech System 328 Petr HoraÂk 34 Using the COST 249 Reference Speech Recogniser for Automatic Speech Segmentation 339 Narada D. Warakagoda and Jon E. Natvig Part V Future Challenges 349 35 Future Challenges 351 Eric Keller 36 Towards Naturalness, or the Challenge of Subjectiveness 353 GenevieÁve Caelen-Haumont 37 Synthesis Within Multi-Modal Systems 363 Andrew Breen 38 A Multi-Modal Speech Synthesis Tool Applied to Audio-Visual Prosody 372 Jonas Beskow,BjoÈrn GranstroÈm and David House 39 Interface Design for Speech Synthesis Systems 383 Gudrun Flach Index 391

About the Author :
E. Keller is the editor of Improvements in Speech Synthesis: Cost 258: The Naturalness of Synthetic Speech, published by Wiley. G. Bailly is the editor of Improvements in Speech Synthesis: Cost 258: The Naturalness of Synthetic Speech, published by Wiley.