Automatic pitch accent contour transcription for Indian languages

Abstract

In this paper, an automatic method to transcribe the pitch accent contour from the speech signal is presented. Pitch contour transcription refers to the labeling of temporal variations of the pitch contour of the speech signal with finite number of discrete labels. Pitch contour is derived from the zero frequency filtered (ZFF) speech signal. A non-linear smoothing technique is used to remove the spurious pitch values in the pitch contour. An intonation like contour is obtained by removing trend in the pitch contour. The location of the tonal variations in the intonation phrases is identified and assigned with appropriate tone label. Pitch contour transcription is derived using tonal labels and the corresponding timing information from the pitch contour. The Automatic pitch contour transcription system is evaluated using read, extempore and conversation modes of speech from 11 Indian languages. For each mode of speech, the speaker-wise subjective evaluation is carried out for 11 Indian languages to validate the correctness of the proposed automatic pitch contour transcription method.