decodeAudioData

Summary

Asynchronously decodes the audio file data contained in the ArrayBuffer. The ArrayBuffer can, for example, be loaded from an XMLHttpRequest with the new responseType and response attributes. Audio file data can be in any of the formats supported by the audio element.

The decodeAudioData() method is preferred over the createBuffer() from ArrayBuffer method because it is asynchronous and does not block the main JavaScript thread.

Method of apis/webaudio/AudioContextapis/webaudio/AudioContext

Syntax

var  = AudioContext.decodeAudioData(audioData, successCallback, errorCallback);

Parameters

audioData

Data-type

String

An ArrayBuffer containing audio file data.

successCallback

Data-type

function

A callback function which will be invoked when the decoding is finished. The single argument to this callback is an AudioBuffer representing the decoded PCM audio data.

errorCallback

Data-type

function

(Optional)

A callback function which will be invoked if there is an error decoding the audio file data.

Return Value

Returns an object of type

Examples

var audioCtx = new AudioContext();
audioCtx.decodeAudioData(audioData, function(buffer) { ... };);

Notes

The older callback-based system is still in the spec for legacy reasons and is currently supported across browsers that support the Web Audio API. It is to be superceded by the newer promise-based syntax, which is in the latest spec, but not yet supported by any browser.

See http://webaudio.github.io/web-audio-api/.

Related specifications

W3C Web Audio API

W3C Editor’s Draft