

Silvet: Shift-Invariant Latent Variable Transcription
=====================================================

A polyphonic music transcription plugin.

    http://code.soundsoftware.ac.uk/projects/silvet

Silvet is a Vamp plugin (http://vamp-plugins.org) for automatic music
transcription, using the method of "A Shift-Invariant Latent Variable
Model for Automatic Music Transcription" by Emmanouil Benetos and
Simon Dixon (see CITATION file).


What does it do?
----------------

Silvet listens to audio recordings of music and tries to work out what
notes are being played.

To use Silvet, you need a Vamp plugin host such as Sonic Visualiser
(http://sonicvisualiser.org). How to use the plugin will depend on the
host, but in the case of Sonic Visualiser, you should load an audio
file and then run Silvet Note Transcription from the Transform
menu. This will add a note layer to your session with the
transcription in it, which you can play back or export as a MIDI file.


How good is it?
---------------

It's reasonable for recordings that suit it: chamber music, solo
piano, acoustic jazz, etc. But the range of music that works well is
quite limited at this stage.

Silvet uses a probablistic latent-variable estimation method to
decompose a Constant-Q time-frequency matrix into note activations
using a set of spectral templates learned from recordings of solo
instruments. This means its performance is dominated by the
correspondence between its instrument templates and the sounds present
in the recording.

The method performs quite well (70-85% of notes identified correctly)
for clear recordings that contain only instruments with a good
correspondence to the known templates. In these cases its performance
becomes limited by the note decomposition step, clustering pitch
probabilities into note events, which is still fairly simplistic.

Silvet does not yet contain any vocal templates, or templates for
typical rock or electronic instruments. So it will usually perform
very poorly with pop and rock music, although the results can be
interesting anyway. Silvet also makes no attempt to transcribe
percussion.

For a formal evaluation, please refer to the 2012 edition of MIREX,
the Music Information Retrieval Evaluation Exchange, where the basic
method implemented in Silvet formed the BD1, BD2 and BD3 submissions
in the Multiple F0 Tracking task:

http://www.music-ir.org/mirex/wiki/2012:Multiple_Fundamental_Frequency_Estimation_%26_Tracking_Results


Authors
-------

The Silvet plugin code was adapted by Chris Cannam from research and a
MATLAB implementation by Emmanouil Benetos.


Citation, License and Use
-------------------------

If you make use of this software for any public or commercial purpose,
we ask you to kindly mention the authors and Queen Mary, University of
London in your user-visible documentation. We're very happy to see
this sort of use but would much appreciate being credited, independent
of the requirements of the software license itself (see below).

If you make use of this software for academic purposes, please cite:

  Emmanouil Benetos and Simon Dixon, "A Shift-Invariant Latent
  Variable Model for Automatic Music Transcription".
  Computer Music Journal, volume 36 no 4, 2012, pp. 81-94.

(See the CITATION file for a BibTeX reference.)

This plugin is Copyright 2014 Queen Mary, University of London. It is
distributed under the GNU General Public License: see the file COPYING
for details.
