Methods and Tool for Constructing Phonetically-Balanced Materials for Speech Perception Testing: A Development of Thai Sentence-Length Materials
This paper proposes a work on phonetically balanced sentence (PB) and phonetically distributed sentence (PD) set, which are parts of the text prompt for speech recording in Large Vocabulary Continuous Speech Recognition (LVCSR) corpus for Thai language. Firstly, a protocol of Thai phonetic transcription and some essential rules of phonetic correction after grapheme-to-phoneme (G2P) process are described. An iterative procedure of PB and PD sentence selection is conducted in order to avoid tedious work of manual phone correction on all initial sentences. A standard text corpus, ORCHID, was chosen for the initial text. Analysis of several attributes such as the number of words, syllables, monophones and biphones, phone’s distribution, etc., in both the PB and PD sets are reported. At the end, the final selected PB are partially compared to the American English TIMIT’s PB set (MIT-450) and the Japanese ATR’s 503 PB set.