beats

A naive but generic beat-detection module.

Usage

detect = require('beats')(bins[, minSeparation])

Takes an array of bins, and an optional minSeparation value which determines the minimum amount of time between beats for each bin (defaults to 0).

Each bin takes the following options:

{
  // the minimum index to sample in
  // the frequencies array.
    lo: 0
  // The maximum index to sample in
  // the frequencies array.
  , hi: 512
  // The minimum volume at which to
  // trigger a beat for this bin.
  , threshold: 0
  // the amount by which to decay
  // the threshold for this bin for
  // each sampled frame.
  , decay: 0.005
}

result = detect(frequencies[, dt])

Returns a Float32Array containing the beats for the current frame: one element per bin. If an element's value is 0, then there is no beat this frame. Otherwise, the value will match the average volume of the bin's frequencies.

frequencies is an array of audio frequencies for the current frame. dt is the amount of time between this frame and the last one - it defaults to 1.

License

MIT. See LICENSE.md for details.