Time-Span Tree Analyzer for Polyphonic Music
Masatoshi Hamanaka, Keiji Hirata, Satoshi Tojo · Institutional Repositories DataBase (IRDB) · 2013
We have been developing a music analysis system called a polyphonic music time-span tree analyzer (PTTA). A time-span tree assigns a hierarchy of 'structural importance' to the notes of a piece of music on the basis of the Generative Theory of Tonal Music (GTTM). However, the theory only accepts homophonic music. To solve this problem, we first record the composers' processes for arranging from polyphony to homophony because the processes show how a musician reduces ornamental notes. Using the recording of the arrangement process with the time-span tree of the homophony, we manually acquire a time-span tree of polyphony. Then we attempt to develop a PTTA that semi-automatically acquires a time-span tree of polyphony by implementing an additional novel rule for time-span analysis. Experimental results show that the PTTA using our proposed rules outperforms the baseline.