Non-linear pitch modification in voice conversion using artificial neural networks

Abstract

Majority of the current voice conversion methods do not focus on the modelling local variations of pitch contour, but only on linear modification of the pitch values, based on means and standard deviations. However, a significant amount of speaker related information is also present in pitch contour. In this paper we propose a non-linear pitch modification method for mapping the pitch contours of the source speaker according to the target speaker pitch contours. This work is done within the framework of Artificial Neural Networks (ANNs) based voice conversion. The pitch contours are represented with Discrete Cosine Transform (DCT) coefficients at the segmental level. The results evaluated using subjective and objective measures confirm that the proposed method performed better in mimicking the target speaker's speaking style when compared to the linear modification method. © 2013 Springer-Verlag Berlin Heidelberg.