Computer improvisation of blues melodies.

Abstract

A computer program has been written that generates blues melodies to fit input chord progressions. The program uses a combination of stochastic methods and high-level rules. Second-order Markov models govern the generation of pitches and rhythms, with fall back procedures (to first- and zero-order models) used to deal with zero-frequency problems. Pitches and rhythms are generated by independent processes; an experimental goal is to determine the degree to which these processes may be linked. The rhythm model uses rhythmic patterns of varying lengths, thus incorporating a moderately variable time scale. Long-term time scale factors are controlled by rules operating at the phrase level. Output from the program will be judged by listeners to determine the degree to which the program captures the structure of blues melodies. Results of these listening experiments will be presented at the conference.