Name pronunciation in German text-to-speech synthesis

Name pronunciation in German text-to-speech synthesis Stefanie Jannedy Linguistics Dept. Ohio State University Columbus, OH 43210, USA j annedy©ling, ohio-state, edu Bernd MSbius Language Modeling Research Bell Laboratories Murray Hill, NJ 07974, USA bmo©research, bell-labs, com Abstract We describe the name analysis and pro- nunciation component in the German ver- sion of the Bell Labs multilingual text-to- speech system. We concentrate on street names because they encompass interest- ing aspects of geographical and personal names. The system was implemented in the framework of finite-state transducer technology, using linguistic criteria as well as frequency distributions derived from a database. In evaluation experiments, we compared the performances of the general- purpose text analysis and the name-specific system on training and test materials. The name-specific system significantly outper- forms the generic system. The error rates compare favorably with results reported in the research literature. Finally, we discuss areas for future work. 1 Introduction The correct pronunciation of names is one of the biggest challenges for text-to-speech (TTS) conver- sion systems. At the same time, many current or en- visioned applications, such as reverse directory sys- tems, automated operator services, catalog ordering or navigation systems, to name just a few, crucially depend upon an accurate and intelligible pronuncia- tion of names. Besides these specific applications, any kind of well-formed text input to a general- purpose TTS system is extremely likely to contain names, and the system has to be well equipped to process these names. This requirement was the main motivation to develop a name analysis and pronunci- ation component for the German version of the Bell Labs multilingual text-to-speech system (GerTTS) (M6bius et al., 1996). Names are conventionally categorized into per- sonal names (first and surnames), geographical names (place, city and street names), and brand names (organization, company and product names). 49 In this paper, we concentrate on street names be- cause they encompass interesting aspects of geo- graphical as well as of personal names. Linguistic de- scriptions and criteria as well as statistical considera- tions, in the sense of frequency distributions derived from a large database, were used in the construction of the name analysis component. The system was implemented in the framework of finite-state trans- ducer (FST) technology (see (Sproat, 1992) for a discussion focussing on morphology). For evalua- tion purposes, we compared the performances of the generM-purpose text analysis and the name-specific systems on training and test materials. As of now, we have neither attempted to deter- mine the etymological or ethnic origin of names, nor have we addressed the problem of detecting names in arbitrary text. However, due to the integration of the name component into the general text analysis system of GerTTS, the latter problem has a reason- able solution. 2 Some problems in name analysis What makes name pronunciation difficult, or spe- cial, in comparison to words that are considered as regular entries in the lexicon of a given language? Various reasons are given in the research literature (Carlson, GranstrSm, and LindstrSm, 1989; Macchi and Spiegel, 1990; …

Content truncated to 500 words