Neutral to Target Speech Conversion using Polynomial Curve Fitting.

摘要

This paper propose a work in emotion conversion of neutral speech signal to target signals like sad speech, fear speech and anger speech signals. A method called curve fit using polynomials is proposed for converting the given neutral speech signal to a target emotional speech signals like sad and fear. As pitch plays an important role in emotion expression, here pitch contour is modified first by using the method of curve fit using polynomials and then speech parameters are modified. Sad and fear speech signals are synthesized by modifying speech/prosodic parameters like pitch contour, intensity contour and duration contour. Anger speech signal are synthesized by modifying prosodic parameters like pitch range, shift pitch frequency, intensity contour and duration contour. The target speech is compared with resultant speech obtained by modifying only the pitch contour and also have observed the improvements in quality of expression due to modification of spectral energy. The method curve fit using polynomials results in good quality for neutral to sad speech and neutral to fear speech conversions and from neutral to anger the speech conversion quality is not up to the mark.