Text Normalization for Bangla, Khmer, Nepali, Javanese, Sinhala, and Sundanese TTS Systems

Keshan Sodimana
Pasindu De Silva
Chen Fang Li
Supheakmungkol Sarin
Knot Pipatsrisawat
6th International Workshop on Spoken Language Technologies for Under-Resourced Languages (SLTU-2018), International Speech Communication Association (ISCA), 29--31 August, Gurugram, India, pp. 147-151


Text normalization is the process of converting non-standard words (NSWs) such as numbers, abbreviations, and time expressions into standard words so that their pronunciations can be derived either through lexicon lookup or by utilizing a program to predict pronunciations from spellings. Text normalization is, thus, an important component of any Text-to-Speech (TTS) system. Without such component, the resulting voice, no matter how good the quality is, may sound unintelligent. Such a component is often built manually by translating language-specific knowledge into rules that can be utilized by TTS pipelines. In this paper, we describe an approach to develop a rule-based text normalization component for many low-resourced languages. We also describe our open source repository containing text normalization grammars for Bangla, Javanese, Khmer, Nepali, Sinhala, Sundanese and present a recipe for utilizing them in a TTS system.