In this paper, the authors discuss the concept of adaptive music soundtracks and sound effects in video games. They propose a novel development called, 'background music reactive games'. In this system, rather than the music reacting to the game, the game reacts to the background music. In developing this system the authors have focussed on the use of MIDI-based background music as a means through which to control video game parameters. The paper includes the results of some initial beta testing.
Using MIDI to Modify Video Game Content
Havukainen, Kai, Arrasvuori, Juha, Holm, Jukka
International Conference on New Interfaces for Musical Expression : 65-70.