Automated estimation of ride cymbal swing ratios in jazz recordings

In this paper, we propose a new method suitable for the automatic analysis of microtiming played by drummers in jazz recordings. Specifically, we aim to estimate the drummers' swing ratio in excerpts of jazz recordings taken from the Weimar Jazz Database. A first approach is based on automatic detection of ride cymbal (RC) onsets and evaluation of relative time intervals between them. However, small errors in the onset detection propagate considerably into the swing ratio estimates. As our main technical contribution, we propose to use the log-lag autocorrelation function (LLACF) as a mid-level representation for estimating swing ratios, circumventing the error-prone detection of RC onsets. In our experiments, the LLACF-based swing ratio estimates prove to be more reliable than the ones based on RC onset detection. Therefore, the LLACF seems to be the method of choice to process large amounts of jazz recordings. Finally, we indicate some implications of our method for microtiming studies in jazz research.