Implementing "A Generative Theory of Tonal Music",
Masatoshi Hamanaka, Keiji Hirata and Satoshi Tojo
Abstract:
This paper proposes a music analysing system called the automatic
time-span tree analyser (ATTA). ATTA derives a time-span tree that
assigns a hierarchy of "structural importance" to the notes of a piece
of music based on the generative theory of tonal music
(GTTM). Although the time-span tree has been applied in music
summarization and collaborative music creation systems, these systems
use time-span trees manually analysed by experts in musicology.
Current systems based on GTTM cannot acquire a time-span tree without
manual application of most of the rules, since GTTM does not resolve
much of the ambiguity involved in the application of the rules. To
solve this problem, we propose a novel computational model of GTTM
that re-formalizes the rules through a computer implementation. The
main advantage of our approach is thatwe can introduce adjustable
parameters, which enables us to assign priorities to the rules. Our
analyser automatically acquires time-span trees by configuring the
parameters that cover 17 out of 26 GTTM rules for constructing a
time-span tree. Experimental results show that after these parameters
were tuned, our method could outperform a baseline performance. We
hope to distribute the time-span tree analyser as a tool for various
musical tasks, such as searching and arranging music.