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次へ: Tempo Estimation 上へ: HMM Using Rhythm Vectors 戻る: Rhythm Estimation: Search Problem

Multiphonic Case

The above stated method can also be applied to the multiphonic case. Projecting the onset timings of all notes in a multiphonic music score onto a one-dimensional time axis, we obtain a ``rhythm score'' from which the $n$-gram ``grammar'' can be defined in the same way. After preprocessing for grouping nearly simultaneous onsets, the rhythm score is recognized from the input sequence of IOIs across multiple voices in the observed MIDI signal, followed by postprocessing for assigning note length to each of recognized note onsets.