Occurrence and duration modeling of sentence medial pause for Bangla text reading at different speech rate

One of the key issues for speech prosody is control of pause occurrence and duration. Occurrence of pause is unconditional at sentence boundaries with high probability at major syntactic boundaries such as clause boundaries and more or less arbitrarily at minor syntactic boundaries for text-readout speech. In this paper a detailed investigation is conducted for sentence-medial pauses for readout speech of Bangla for different speech rates. Based on the analysis, linear models with variables of syntactic unit length in terms of number of syllable and distance to directly modifying word are constructed for pause occurrence and duration for different speech rates. The models are evaluated using the test data which are not included in the analyzed data in different speech rates. The results show that the proposed models can predict occurrence probability correctly on average 82% cases for all speech rate, and pause duration within ±100 ms for 79% of the cases.