AudioContext.createMediaStreamSource()

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规范
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createMediaStreamSource() 方法在 AudioContext Interface is used to create a new MediaStreamAudioSourceNode object, given a media stream (say, from a MediaDevices.getUserMedia instance), the audio from which can then be played and manipulated.

For more details about media stream audio source nodes, check out the MediaStreamAudioSourceNode reference page.

句法

audioSourceNode = audioContext.createMediaStreamSource(stream);

参数

stream: MediaStream to serve as an audio source to be fed into an audio processing graph for use and manipulation.

返回值

新的 MediaStreamAudioSourceNode object representing the audio node whose media is obtained from the specified source stream.

范例

In this example, we grab a media (audio + video) stream from navigator.getUserMedia , feed the media into a <video> element to play then mute the audio, but then also feed the audio into a MediaStreamAudioSourceNode . Next, we feed this source audio into a low pass BiquadFilterNode (which effectively serves as a bass booster), then a AudioDestinationNode .

The range slider below the <video> element controls the amount of gain given to the lowpass filter — increase the value of the slider to make the audio sound more bass heavy!

注意 : You can see this example running live ，或 view the source .

var pre = document.querySelector('pre');
var video = document.querySelector('video');
var myScript = document.querySelector('script');
var range = document.querySelector('input');
// getUserMedia block - grab stream
// put it into a MediaStreamAudioSourceNode
// also output the visuals into a video element
if (navigator.mediaDevices) {
    console.log('getUserMedia supported.');
    navigator.mediaDevices.getUserMedia ({audio: true, video: true})
    .then(function(stream) {
        video.srcObject = stream;
        video.onloadedmetadata = function(e) {
            video.play();
            video.muted = true;
        };
        // Create a MediaStreamAudioSourceNode
        // Feed the HTMLMediaElement into it
        var audioCtx = new AudioContext();
        var source = audioCtx.createMediaStreamSource(stream);
        // Create a biquadfilter
        var biquadFilter = audioCtx.createBiquadFilter();
        biquadFilter.type = "lowshelf";
        biquadFilter.frequency.value = 1000;
        biquadFilter.gain.value = range.value;
        // 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(biquadFilter);
        biquadFilter.connect(audioCtx.destination);
        // Get new mouse pointer coordinates when mouse is moved
        // then set new gain value
        range.oninput = function() {
            biquadFilter.gain.value = range.value;
        }
    })
    .catch(function(err) {
        console.log('The following gUM error occured: ' + err);
    });
} else {
   console.log('getUserMedia not supported on your browser!');
}
// dump script to pre element
pre.innerHTML = myScript.innerHTML;

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

规范

规范	状态	注释
Web 音频 API The definition of 'AudioContext.createMediaStreamSource()' in that specification.	工作草案

浏览器兼容性

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request. 更新 GitHub 上的兼容性数据

	桌面						移动
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`createMediaStreamSource`	Chrome 14	Edge 12	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
不支持

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使用 Web 音频 API

元数据

最后修改： Jul 10, 2019

Web 音频 API
AudioContext
构造函数
1. AudioContext()
特性
1. baseLatency
2. outputLatency
方法
1. baseLatency
2. close()
3. ~~createJavaScriptNode()~~
4. createMediaElementSource()
5. createMediaStreamDestination()
6. createMediaStreamSource()
7. createMediaStreamTrackSource()
8. ~~createWaveTable()~~
9. getOutputTimestamp()
10. outputLatency
11. resume()
12. suspend()
继承：
1. EventTarget
Related pages for Web Audio API

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句法

参数

返回值

范例

规范

浏览器兼容性

图例

另请参阅

相关话题