- S. A. Thati, B. Raj, B. Yegnanarayana, K. Prahallad. 2011. A Comparison of Prosody Modification using Instants of Significant Excitation and Mel-Cepstral Vocoder. Abstract: In this paper, we compare two methods for prosody (duration and pitch) modification. These are prosody modification using instants of Significant Excitation and Mel-Cepstral vocoder. We show that duration modifications are better using Mel- Cepstral vocoder for higher modification factor while pitch modifications are better using instants of Significant Excitations. In the end we show that Mel-Cepstral vocoder provides flexibility for non-uniform prosody manipulation. method using Instants of Significant Excitation (epochs) was proposed (3). This method operates on the linear prediction (LP) residual of signal and incorporates desired features by using the knowledge of epochs. Prosody modification in the residual domain is believed to reduce the spectral and phase distortions. Most of the above methods are non-parametric, as they rely heavily on the speech production model and there is no explicit estimation of the model parameters. Other techniques have been proposed in which the parameters of a speech production model are estimated, and explicitly used in the modification/synthesis stages. The most straightforward of such approaches was the Linear Predictive Vocoder (4), but has now been abandoned because of its inability to provide high-quality modifications. Another such approach using Mel- Cepstral Vocoder represents a more promising approach be- cause the estimated parameters are considered to be highly
