Developing a Text to Speech System for Dzongkha

Abstract

Text to Speech plays a vital role in imparting information to the general population who have difficulty reading text but can understand spoken language. In Bhutan, many people fall in this category in adopting the national language ‘Dzongkha’ and system of such kind will have advantages in the community. In addition, the language will heighten its digital evolution in narrowing the digital gap. The same is more important in helping people with visual impairment. Text to speech systems are widely used in talking BOTs to news readers and announcement systems. This paper presents an attempt towards developing a working model of Text to Speech system for Dzongkha language. It also presents the development of a transcription or grapheme table for phonetic transcription from Dzongkha text to its equivalent phone set. The transcription tables for both consonants and vowels have been prepared in such a way that it facilitates better compatibility in computing. A total of 3000 sentences have been manually transcribed and recorded with a single male voice. The speech synthesis is based on a statistical method with concatenative speech generation on FESTIVAL platform. The model is generated using the two variants CLUSTERGEN and CLUNITS of the FESTIVAL speech tools FESTVOX. The development of system prototype is of the first kind for the Dzongkha language.

Keywords: Natural Language processing (NLP), Dzongkha, Text to speech (TTS) system, Statistical speech synthesis, phoneme, corpus, transcription

DOI: 10.7176/CEIS/12-1-04

Publication date: January 31^st 2021