NAME
  aubioonset - a command line tool to extract musical onset times

SYNOPSIS

  aubioonset source
  aubioonset [[-i] source] [-o sink]
             [-r rate] [-B win] [-H hop]
             [-O method] [-t thres]
             [-T time-format]
             [-s sil] [-m] [-f]
             [-j] [-N miditap-note] [-V miditap-velo]
             [-v] [-h]

DESCRIPTION

  aubioonset attempts to detect onset times, the beginning of discrete sound
  events, in audio signals.

  When started with an input source (-i/--input), the detected onset times are
  given on the console, in seconds.

  When started without an input source, or with the jack option (-j/--jack),
  aubioonset starts in jack mode.

OPTIONS

  This program follows the usual GNU command line syntax, with long options
  starting with two dashes (--). A summary of options is included below.

  -i, --input source  Run analysis on this audio file. Most uncompressed and
  compressed are supported, depending on how aubio was built.

  -o, --output sink  Save results in this file. The file will be created on
  the model of the input file. Onset times are marked by a short wood-block
  like sound.

  -r, --samplerate rate  Fetch the input source, resampled at the given
  sampling rate. The rate should be specified in Hertz as an integer. If 0,
  the sampling rate of the original source will be used. Defaults to 0.

  -B, --bufsize win  The size of the buffer to analyze, that is the length
  of the window used for spectral and temporal computations. Defaults to 512.

  -H, --hopsize hop  The number of samples between two consecutive analysis.
  Defaults to 256.

  -O, --onset method  The onset detection method to use. See ONSET METHODS
  below. Defaults to 'default'.

  -t, --onset-threshold thres  Set the threshold value for the onset peak
  picking. Values are typically in the range [0.001, 0.900]. Lower threshold
  values imply more onsets detected. Increasing this threshold should reduce
  the number of incorrect detections. Defaults to 0.3.

  -M, --minioi value  Set the minimum inter-onset interval, in seconds, the
  shortest interval between two consecutive onsets. Defaults to 0.020

  -s, --silence sil  Set the silence threshold, in dB, under which the onset
  will not be detected. A value of -20.0 would eliminate most onsets but the
  loudest ones. A value of -90.0 would select all onsets. Defaults to -90.0.

  -T, --timeformat format  Set time format (samples, ms, seconds). Defaults to
  seconds.

  -m, --mix-input  Mix source signal to the output signal before writing to
  sink.

  -f, --force-overwrite  Overwrite output file if it already exists.

  -j, --jack  Use Jack input/output. You will need a Jack connection
  controller to feed aubio some signal and listen to its output.

  -N, --miditap-note  Override note value for MIDI tap. Defaults to 69.

  -V, --miditap-velop  Override velocity value for MIDI tap. Defaults to 65.

  -h, --help  Print a short help message and exit.

  -v, --verbose  Be verbose.

ONSET METHODS

  Available methods are:

  default  Default distance, currently hfc

  Default: 'default' (currently set to hfc)

  energy  Energy based distance

  This function calculates the local energy of the input spectral frame.

  hfc  High-Frequency content

  This method computes the High Frequency Content (HFC) of the input
  spectral frame. The resulting function is efficient at detecting
  percussive onsets.

  Paul Masri. Computer modeling of Sound for Transformation and Synthesis of
  Musical Signal. PhD dissertation, University of Bristol, UK, 1996.

  complex  Complex domain onset detection function

  This function uses information both in frequency and in phase to determine
  changes in the spectral content that might correspond to musical onsets.
  It is best suited for complex signals such as polyphonic recordings.

  Christopher Duxbury, Mike E. Davies, and Mark B. Sandler.  Complex domain
  onset detection for musical signals. In Proceedings of the Digital Audio
  Effects Conference, DAFx-03, pages 90-93, London, UK, 2003.

  phase  Phase based onset detection function

  This function uses information both in frequency and in phase to determine
  changes in the spectral content that might correspond to musical onsets. It
  is best suited for complex signals such as polyphonic recordings.

  Juan-Pablo Bello, Mike P. Davies, and Mark B. Sandler.  Phase-based note
  onset detection for music signals. In Proceedings of the IEEE International
  Conference on Acoustics Speech and Signal Processing, pages 441­444,
  Hong-Kong, 2003.

  specdiff  Spectral difference onset detection function

  Jonhatan Foote and Shingo Uchihashi. The beat spectrum: a new approach to
  rhythm analysis. In IEEE International Conference on Multimedia and Expo
  (ICME 2001), pages 881­884, Tokyo, Japan, August 2001.

  kl  Kulback-Liebler onset detection function

  Stephen Hainsworth and Malcom Macleod. Onset detection in music audio
  signals. In Proceedings of the International Computer Music Conference
  (ICMC), Singapore, 2003.

  mkl  Modified Kulback-Liebler onset detection function

  Paul Brossier, ``Automatic annotation of musical audio for interactive
  systems'', Chapter 2, Temporal segmentation, PhD thesis, Centre for
  Digital music, Queen Mary University of London, London, UK, 2006.

  specflux  Spectral flux

  Simon Dixon, Onset Detection Revisited, in ``Proceedings of the 9th
  International Conference on Digital Audio Effects'' (DAFx-06), Montreal,
  Canada, 2006.

SEE ALSO

  aubiopitch(1),
  aubiotrack(1),
  aubionotes(1),
  aubioquiet(1),
  aubiomfcc(1),
  and
  aubiocut(1).

AUTHOR

  This manual page was written by Paul Brossier <piem@aubio.org>. Permission is
  granted to copy, distribute and/or modify this document under the terms of
  the GNU General Public License as published by the Free Software Foundation,
  either version 3 of the License, or (at your option) any later version.
