Spectral Flatness Analysis for Emotional Speech Synthesis and Transformation

摘要

According to psychological research of emotional speech different emotions are accompanied by different spectral noise. We control its amount by spectral flatness according to which the high frequency noise is mixed in voiced frames during cepstral speech synthesis. Our experiments are aimed at statistical analysis of spectral flatness in three emotions (joy, sadness, anger), and a neutral state for comparison. Calculated histograms of spectral flatness distribution are visually compared and modelled by Gamma probability distribution. Obtained statistical parameters and emotional-to-neutral ratios of their mean values show good correlation for both male and female voices and all three emotions.