Duration and intonation in emotional speech

Three experiments investigated the role of duration and intonation in the expression of emotions in natural and synthetic speech. Two sentences of an actor portraying seven emotions (neutral, joy, boredom, anger, sadness, fear, indignation) were acoustically analyzed. By copying pitch and duration of the original utterances to a monotonous one, it could be shown that both factors were sufficient to express the various emotions. In the second part, rules about intonation and duration were derived and tested. These rules were applied to resynthesized natural speech and synthetic speech generated from LPC-coded diphones. The results showed that emotions can be expressed accurately by manipulating pitch and duration in a rule-based way.