AudioContext.createConvolver()
The createConvolver()
method of the AudioContext
interface creates a ConvolverNode
, which is commonly used to apply reverb effects to your audio. See the spec definition of Convolution for more information.
Syntax
var audioCtx = new AudioContext(); var convolver = audioCtx.createConvolver();
Returns
Example
The following example shows basic usage of an AudioContext to create a convolver node. The basic premise is that you create an AudioBuffer containing a sound sample to be used as an ambience to shape the convolution (called the impulse response,) and apply that to the convolver. The example below uses a short sample of a concert hall crowd, so the reverb effect applied is really deep and echoey.
For applied examples/information, check out our Voice-change-O-matic demo (see app.js for relevant code).
var audioCtx = new (window.AudioContext || window.webkitAudioContext)(); var convolver = audioCtx.createConvolver(); ... // grab audio track via XHR for convolver node var soundSource, concertHallBuffer; ajaxRequest = new XMLHttpRequest(); ajaxRequest.open('GET', 'concert-crowd.ogg', true); ajaxRequest.responseType = 'arraybuffer'; ajaxRequest.onload = function() { var audioData = ajaxRequest.response; audioCtx.decodeAudioData(audioData, function(buffer) { concertHallBuffer = buffer; soundSource = audioCtx.createBufferSource(); soundSource.buffer = concertHallBuffer; }, function(e){"Error with decoding audio data" + e.err}); } ajaxRequest.send(); ... convolver.buffer = concertHallBuffer;
Specifications
Specification | Status | Comment |
---|---|---|
Web Audio API The definition of 'createConvolver()' in that specification. |
Working Draft |
Browser compatibility
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 |
Feature | Android | Firefox Mobile (Gecko) | Firefox OS | IE Mobile | Opera Mobile | Safari Mobile | Chrome for Android |
---|---|---|---|---|---|---|---|
Basic support | ? | 26.0 | 1.2 | ? | ? | ? | 33.0 |
See also
License
© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-us/docs/web/api/audiocontext/createconvolver