Acoustic analysis of vowels in five low resource north East Indian languages of Nagaland

This paper describes acoustic analysis of vowels in five different low resource languages of Nagaland namely Nagamese, Ao, Lotha, Sumi and Angami from North-Eastern India. Six major vowels (/u/, /o/, /a/, /a/, /e/, /i/) are studied for these languages to build up the characteristic features of these languages from readout speech. Vowel duration and 1 ^st , 2 ^nd and 3 ^rd formant i.e. F1, F2 and F3 are investigated and analyzed for these languages. Using these vowels' knowledge, a small Language Identification module has been developed and tested with unseen samples of the above said languages. Result shows that instead of considering F1, F2 and vowel duration only, inclusion of F3 markedly improves the performance for identification of Nagaland languages except for Nagamese. This initial study unveils the importance of vowel characteristics. The result of language identification is also encouraging for these low resource languages.