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
.
mediaElement
Read only- The
HTMLMediaElement
used when constructing thisMediaStreamAudioSourceNode
.
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.
Note: You can also view this example running live, or view the source.
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
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
MediaElementAudioSourceNode | Chrome Full support 14 | Edge Full support ≤18 | Firefox Full support 25 | IE No support No | Opera Full support 15 | Safari Full support 6 | WebView Android Full support Yes | Chrome Android Full support 18 | Firefox Android Full support 26 | Opera Android Full support 14 | Safari iOS Full support Yes | Samsung Internet Android Full support 1.0 |
MediaElementAudioSourceNode() constructor | Chrome
Full support
55
| Edge Full support ≤79 | Firefox Full support 53 | IE No support No | Opera Full support 42 | Safari ? | WebView Android
Full support
55
| Chrome Android
Full support
55
| Firefox Android Full support 53 | Opera Android Full support 42 | Safari iOS ? | Samsung Internet Android
Full support
6.0
|
mediaElement | Chrome Full support Yes | Edge Full support ≤79 | Firefox Full support 70 | IE No support No | Opera Full support Yes | Safari Full support Yes | WebView Android Full support Yes | Chrome Android Full support Yes | Firefox Android No support No | Opera Android Full support Yes | Safari iOS Full support Yes | Samsung Internet Android Full support Yes |
Legend
- Full support
- Full support
- No support
- No support
- Compatibility unknown
- Compatibility unknown
- See implementation notes.
- See implementation notes.