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]
                  [-s sil] [-m] [-f]
                  [-j] [-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.  Typical
              values  are  typically  within 0.001 and 0.900. Defaults to 0.1.
              Lower threshold values imply more onsets detected.  Try  0.5  in
              case of over-detections. Defaults to 0.3.

       -s, --silence sil
              Set the silence threshold, in dB, under which the pitch 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.

       -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.

       -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.