The Influence of Chord Duration Modeling on Chord and Local Key Extraction

In this paper, we investigate the effect of different types of chord duration modeling on the performance of a simultaneous chord and local key extraction system. Two hypotheses are examined, (1) whether the introduction of multiple states per key-chord combination makes any difference as it changes the prior duration from a geometric distribution to a negative binomial distribution, and (2) whether making the prior mean duration of a key-chord combination a function of the chord has a positive effect. We found that the introduction of multiple states per key-chord has no influence on neither key nor chord extraction performance, but making the mean duration a function of the chord interpreted in its key leads to an increase in the key estimation capabilities.