AudioContext.createWaveShaper()

The createWaveShaper() method of the AudioContext interface creates a WaveShaperNode, which represents a non-linear distortion. It is used to apply distortion effects to your audio.

SyntaxEdit

var audioCtx = new AudioContext();
var distortion = audioCtx.createWaveShaper();

Returns

A WaveShaperNode.

ExampleEdit

The following example shows basic usage of an AudioContext to create a wave shaper node. For applied examples/information, check out our Voice-change-O-matic demo (see app.js for relevant code).

Note: Distortion curves are not the easiest thing to work out, and you will probably need to look around to find such algorithms. We found the below distortion curve code on Stack Overflow.

var audioCtx = new (window.AudioContext || window.webkitAudioContext)();
var distortion = audioCtx.createWaveShaper();

  ...

function makeDistortionCurve(amount) {
  var k = typeof amount === 'number' ? amount : 50,
    n_samples = 44100,
    curve = new Float32Array(n_samples),
    deg = Math.PI / 180,
    i = 0,
    x;
  for ( ; i < n_samples; ++i ) {
    x = i * 2 / n_samples - 1;
    curve[i] = ( 3 + k ) * x * 20 * deg / ( Math.PI + k * Math.abs(x) );
  }
  return curve;
};

  ...

distortion.curve = makeDistortionCurve(400);
distortion.oversample = '4x';

SpecificationsEdit

Specification Status Comment
Web Audio API
The definition of 'createWaveShaper()' in that specification.
Working Draft  

Browser compatibilityEdit

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 10.0webkit 25.0 (25.0)  Not supported 15.0webkit
22 (unprefixed)
6.0webkit

See alsoEdit

Document Tags and Contributors

 Contributors to this page: teoli, chrisdavidmills
 Last updated by: teoli,