MediaStreamAudioDestinationNode

MediaStreamAudioDestinationNode 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() 方法。

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

构造函数

MediaStreamAudioDestinationNode.MediaStreamAudioDestinationNode()
创建新的 MediaStreamAudioDestinationNode object instance.

特性

Inherits properties from its parent, AudioNode .

MediaStreamAudioDestinationNode.stream
A MediaStream containing a single MediaStreamTrack whose kind is audio and with the same number of channels as the node. 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 .

方法

Inherits methods from its parent, AudioNode .

范例

In the following simple example, we create a MediaStreamAudioDestinationNode , an OscillatorNode 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>
					

注意 : You can view this example live ,或 study the source code , on Github.

规范

规范 状态 Comment
Web 音频 API
The definition of 'MediaStreamAudioDestinationNode' in that specification.
工作草案

浏览器兼容性

更新 GitHub 上的兼容性数据
Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
MediaStreamAudioDestinationNode Chrome 14 Edge ≤18 Firefox 25 IE 不支持 No Opera 15 Safari 6 WebView Android Yes Chrome Android 18 Firefox Android 26 Opera Android 14 Safari iOS Yes Samsung Internet Android 1.0
MediaStreamAudioDestinationNode() 构造函数 Chrome 55
注意事项
55
注意事项
Before Chrome 59, the default values were not supported.
Edge ≤79 Firefox 53 IE 不支持 No Opera 42 Safari ? WebView Android 55
注意事项
55
注意事项
Before Chrome 59, the default values were not supported.
Chrome Android 55
注意事项
55
注意事项
Before Chrome 59, the default values were not supported.
Firefox Android 53 Opera Android 42 Safari iOS ? Samsung Internet Android 6.0
注意事项
6.0
注意事项
Before Samsung Internet 7.0, the default values were not supported.
stream Chrome 14 Edge ≤18 Firefox 25 IE 不支持 No Opera 15 Safari 6 WebView Android Yes Chrome Android 18 Firefox Android 26 Opera Android 14 Safari iOS Yes Samsung Internet Android 1.0

图例

完整支持
完整支持
不支持
不支持
兼容性未知
兼容性未知
见实现注意事项。

另请参阅