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The MediaElementAudioDestinationNode interface represents an audio destination consisting of a WebRTC MediaStream with a single AudioMediaStreamTrack, which can be used in a similar way to a MediaStream obtained from Navigator.getUserMedia.

It is an AudioNode that acts as an audio destination, created using the AudioContext.createMediaStreamDestination method.

Number of inputs 1
Number of outputs 0
Channel count 2
Channel count mode "explicit"
Channel count interpretation "speakers"

Constructor

MediaStreamAudioDestinationNode.MediaStreamAudioDestinationNode()
Creates a new MediaStreamAudioDestinationNode object instance.

Properties

Inherits properties from its parent, AudioNode.

MediaStreamAudioDestinationNode.stream
Is a MediaStream containing a single AudioMediaStreamTrack with the same number of channels as the node itself. You can use this property to get a stream out of the audio graph and feed it into another construct, such as a Media Recorder.

Methods

Inherits methods from its parent, AudioNode.

Example

In the following simple example, we create a MediaStreamAudioDestinationNode, an OscillatorNode and a MediaRecorder (the example will therefore only work in Firefox and Chrome at this time.) The MediaRecorder is set up to record information from the MediaStreamDestinationNode.

When the button is clicked, the oscillator starts, and the MediaRecorder is started. When the button is stopped, the oscillator and MediaRecorder both stop. Stopping the MediaRecorder causes the dataavailable event to fire, and the event data is pushed into the chunks array. After that, the stop event fires, a new blob is made of type opus — which contains the data in the chunks array, and a new window (tab) is then opened that points to a URL created from the blob.

From here, you can play and save the opus file.

<!DOCTYPE html>
<html>
  <head>
    <title>createMediaStreamDestination() demo</title>
  </head>
  <body>
    <h1>createMediaStreamDestination() demo</h1>

    <p>Encoding a pure sine wave to an Opus file </p>
    <button>Make sine wave</button>
    <audio controls></audio>
    <script>
     var b = document.querySelector("button");
     var clicked = false;
     var chunks = [];
     var ac = new AudioContext();
     var osc = ac.createOscillator();
     var dest = ac.createMediaStreamDestination();
     var mediaRecorder = new MediaRecorder(dest.stream);
     osc.connect(dest);

     b.addEventListener("click", function(e) {
       if (!clicked) {
           mediaRecorder.start();
           osc.start(0);
           e.target.innerHTML = "Stop recording";
           clicked = true;
         } else {
           mediaRecorder.stop();
           osc.stop(0);
           e.target.disabled = true;
         }
     });

     mediaRecorder.ondataavailable = function(evt) {
       // push each chunk (blobs) in an array
       chunks.push(evt.data);
     };

     mediaRecorder.onstop = function(evt) {
       // Make blob out of our blobs, and open it.
       var blob = new Blob(chunks, { 'type' : 'audio/ogg; codecs=opus' });
       document.querySelector("audio").src = URL.createObjectURL(blob);
     };
    </script>
  </body>
</html>

Note: You can view this example live, or study the source code, on Github.

Specification

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

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung 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
MediaStreamAudioDestinationNode() 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 Chrome 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
streamChrome 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

Legend

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

See also

Schlagwörter des Dokuments und Mitwirkende

Mitwirkende an dieser Seite: fscholz, chrisdavidmills, anoopelias, teoli, Sebastianz
Zuletzt aktualisiert von: fscholz,