An Application of Evolutionary Algorithms to Music: - Co-Evolving Melodies and Harmonization

Algorithmic composition is a field that is close to 60 years old, and has seen much research. Systems today are able to do a wide range of compositional tasks, ranging from simple melody generation to fully automated orchestral composition. Systems for computer aided composition are becoming more and more common, either to evaluate music created by humans, or as generators of raw material to be used by composers. This Master s Thesis describes a novel implementation of a multi-objective evolutionary algorithm, that is capable of generating short musical ideas consisting of a melody and abstract harmonization. The implementation is capable of creating these ideas based on provided material, or autonomously. Three automated fitness features were adapted to the model to evaluate the generated music during evolution, and a fourth was developed for ensuring harmonic progression. Four rhythmical pattern matching features were also developed. The implementation produced 21 pieces of music, under various configurations, that were evaluated in a study. The results of this study indicates that the system is capable of composing ideas that are subjectively interesting and pleasant, but not consistently