Synthesis and decoding of emotionally expressive music performance

A recently developed application of Director Musices (DM) is presented. The DM is a rule-based software tool for automatic music performance developed at the Speech Music and Hearing Dept. at the Royal Institute of Technology, Stockholm. It is written in Common Lisp and is available both for Windows and Macintosh. It is demonstrated that particular combinations of rules defined in the DM can be used for synthesizing performances that differ in emotional quality. Different performances of two pieces of music were synthesized so as to elicit listeners' associations to six different emotions (fear, anger, happiness, sadness, tenderness, and solemnity). Performance rules and their parameters were selected so as to match previous findings about emotional aspects of music performance. Variations of the performance variables IOI (Inter-Onset Interval), OOI (Offset-Onset Interval) and L (Sound Level) are presented for each rule-setup. In a forced-choice listening test 20 listeners were asked to classify the performances with respect to emotions. The results showed that the listeners, with very few exceptions, recognized the intended emotions correctly. This shows that a proper selection of rules and rule parameters in DM can indeed produce a wide variety of meaningful, emotional performances, even extending the scope of the original rule definition.