Vamp (http://www.vamp-plugins.org/) is an audio processing plugin system that extract descriptive information from audio data — typically referred to as audio analysis plugins or audio feature extraction plugins.
Vamp is the primary analysis plugin format used by Sonic Visualiser and editors like Ardour or Audacity use Vamp plugins for audio analysis.
Many vamp plugins are already availablel, for example:
- note onset detector
- beat tracker
- tempo estimator / tempot tracking
- pitch tracking / note tracking
- key estimator
- tonal change detector
- structural segmenter
- timbral and rhythmic similarity estimator
- chromagram
- constant Q spectrogram and MFCC calculation
- audio fingerprinting
for a full list see http://www.vamp-plugins.org/download.html .
It would be definitely nice to have all these plugins working in PD and also benefit from future extensions to vamp.
Writing a vamp host for PD
A vamp host for PD would need some more work than a simple DSP externals.
As listed on http://www.vamp-plugins.org/rationale.html the following things amongst others have to be considered:
- Plugins have more control over their inputs than a typical real-time processing plugin. For example, they can indicate to the host their preferred processing block and step sizes, and these do not have to be equal.
- Vamp plugins may ask to receive data in the frequency domain instead of the time domain. The host takes the responsibility for converting the input data using an FFT of windowed frames.
Therefore the vamp-host PD external should abstract all the requirements of an individual plugin. This means that FFT and blocksize conversions should be done automatically in the external, making it as easy to use as possible on the patcher level.