MediaElementAudioSourceNode

The MediaElementAudioSourceNode interface represents an audio source consisting of an HTML5 <audio> or <video> element. It is an AudioNode that acts as an audio source.

A MediaElementSourceNode has no inputs and exactly one output, and is created using the AudioContext.createMediaElementSource method. The amount of channels in the output equals the number of channels of the audio referenced by the HTMLMediaElement used in the creation of the node, or is 1 if the HTMLMediaElement has no audio.

Number of inputs 0
Number of outputs 1
Channel count defined by the media in the HTMLMediaElement passed to the AudioContext.createMediaElementSource method that created it.

Constructor

MediaElementAudioSourceNode()
Creates a new MediaElementAudioSourceNode object instance.

Properties

Inherits properties from its parent, AudioNode.

Methods

Inherits methods from its parent, AudioNode.

Example

This simple example creates a source from an <audio> element using createMediaElementSource(), then passes the audio through a GainNode before feeding it into the AudioDestinationNode for playback. When the mouse pointer is moved, the updatePage() function is invoked, which calculates the current gain as a ratio of mouse Y position divided by overall window height. You can therefore increase and decrease the volume of the playing music by moving the mouse pointer up and down.

var audioCtx = new (window.AudioContext || window.webkitAudioContext)();
var myAudio = document.querySelector('audio');
var pre = document.querySelector('pre');
var myScript = document.querySelector('script');

pre.innerHTML = myScript.innerHTML;

// Create a MediaElementAudioSourceNode
// Feed the HTMLMediaElement into it
var source = audioCtx.createMediaElementSource(myAudio);

// Create a gain node
var gainNode = audioCtx.createGain();

// Create variables to store mouse pointer Y coordinate
// and HEIGHT of screen
var CurY;
var HEIGHT = window.innerHeight;

// Get new mouse pointer coordinates when mouse is moved
// then set new gain value

document.onmousemove = updatePage;

function updatePage(e) {
    CurY = (window.Event) ? e.pageY : event.clientY + (document.documentElement.scrollTop ? document.documentElement.scrollTop : document.body.scrollTop);

    gainNode.gain.value = CurY/HEIGHT;
}


// connect the AudioBufferSourceNode to the gainNode
// and the gainNode to the destination, so we can play the
// music and adjust the volume using the mouse cursor
source.connect(gainNode);
gainNode.connect(audioCtx.destination);

Note: As a consequence of calling createMediaElementSource(), audio playback from the HTMLMediaElement will be re-routed into the processing graph of the AudioContext. So playing/pausing the media can still be done through the media element API and the player controls.

Specification

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

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidiOS SafariSamsung Internet
Basic supportChrome Full support 14Edge Full support YesFirefox Full support 25IE No support NoOpera Full support 15Safari Full support 6WebView Android Full support YesChrome Android Full support 18Edge Mobile Full support YesFirefox Android Full support 26Opera Android Full support 15Safari iOS ? Samsung Internet Android Full support Yes
MediaElementAudioSourceNode() constructorChrome Full support 55
Notes
Full support 55
Notes
Notes Before Chrome 59, the default values were not supported.
Edge ? Firefox Full support 53IE No support NoOpera Full support 42Safari ? WebView Android Full support 55
Notes
Full support 55
Notes
Notes Before version 59, the default values were not supported.
Chrome Android Full support 55
Notes
Full support 55
Notes
Notes Before Chrome 59, the default values were not supported.
Edge Mobile ? Firefox Android Full support 53Opera Android Full support 42Safari iOS ? Samsung Internet Android Full support 6.0
mediaElementChrome ? Edge ? Firefox ? IE ? Opera ? Safari ? WebView Android ? Chrome Android ? Edge Mobile ? Firefox Android ? Opera Android ? Safari iOS ? Samsung Internet Android ?

Legend

Full support  
Full support
No support  
No support
Compatibility unknown  
Compatibility unknown
See implementation notes.
See implementation notes.

See also

Document Tags and Contributors

Last updated by: fscholz,