Conveying emotion through music Generating affective background music using cellular automata

Emotion adds affect and improves understanding in humancomputer interaction. Emotion can not only be conveyed to the human user using visual cues like color or facial expression, but also using music. This paper describes development of CAM (Cellular Automata Music) that generates music using cellular automata and adds affect by modifying it according to a few simple rules that are based on detection of emotion in music. Input for the system is emotion which is given as a point on the two dimensional emotion space (2DES). The music is very basic because it lacks properties like patterns or chords, but it should be good enough to be used as background music. The system is evaluated with a user experiment in which participants were asked to indicate perceived emotions while listening to a few fragments. This article describes the state of art of music generation, detection of emotion in music and generating affective music and discusses the design and results of the experiment.