streaming mode | Rhythm category


  • signal (real) - the input audio signal


  • onsets (vector_real) - lists of onsets


  • combine (real ∈ (0, ∞), default = 20) :

    time threshold for double onsets detections (ms)

  • frameSize (integer ∈ (0, ∞), default = 2048) :

    the frame size for computing low-level features

  • hopSize (integer ∈ (0, ∞), default = 256) :

    the hop size for computing low-level features

  • ratioThreshold (real ∈ [0, ∞), default = 16) :

    ratio threshold for peak picking with respect to novelty_signal/novelty_average rate, use 0 to disable it (for low-energy onsets)

  • sampleRate (real ∈ (0, ∞), default = 44100) :

    the audio sampling rate [Hz]

  • threshold (real ∈ [0, ∞), default = 0.05) :

    threshold for peak peaking with respect to the difference between novelty_signal and average_signal (for onsets in ambient noise)


This algorithm detects onsets given an audio signal using SuperFlux algorithm. This implementation is based on the available reference implementation in python [2]. The algorithm computes spectrum of the input signal, summarizes it into triangular band energies, and computes a onset detection function based on spectral flux tracking spectral trajectories with a maximum filter (SuperFluxNovelty). The peaks of the function are then detected (SuperFluxPeaks).


[1] Böck, S. and Widmer, G., Maximum Filter Vibrato Suppression for Onset Detection, Proceedings of the 16th International Conference on Digital Audio Effects (DAFx-13), 2013 [2]

Source code

See also

Flux (standard) Flux (streaming) SuperFluxExtractor (standard) SuperFluxNovelty (standard) SuperFluxNovelty (streaming) SuperFluxPeaks (standard) SuperFluxPeaks (streaming) Vibrato (standard) Vibrato (streaming)