stylization using an optimal piecewise polynomial approximation
Prasanta Kumar Ghosh and Shrikanth Narayanan
IEEE Signal Processing Letters, Volume 16, No. 9, September 2009, pp 810-813
ABSTRACT: We propose a dynamic programming (DP) based piecewise polynomial approximation of discrete data such that the L2 norm of the approximation error is minimized. We apply this technique for the stylization of speech pitch contour. Objective evaluation verifies that the DP based technique indeed yields minimum mean square error (MSE) compared to other approximation methods. Subjective evaluation reveals that the quality of the synthesized speech using stylized pitch contour obtained by the DP method is almost identical to that of the original speech.
(pdf) (Software [matlab code])
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