Estimation of the amount of spectral content present in the reference (tutor) song that is absent from the comparison (tutee) song.
(A) Example reference and comparison songs. To compute the DKL for these songs, we first fit Gaussian mixture models (GMMs) to the data from each song. (B) Representation in one dimension of the GMMs fit to song spectral content for both the reference song (left, blue) and the comparison song (right, red). (C) Superimposed mixture models for the reference song (blue) and comparison song (red). Regions of the reference-song mixture model which are not shared with the comparison-song model (red arrow) correspond to reference song content which is absent in the comparison song and will result in a higher DKL. However, regions of the comparison-song model which are not shared with the reference-song model (green arrow) will not impact the DKL.