AudioContext.createMediaElementSource()

在此页

句法
范例
规范
浏览器兼容性
另请参阅
相关话题

createMediaElementSource() 方法在 AudioContext Interface is used to create a new MediaElementAudioSourceNode object, given an existing HTML <audio> or <video> element, the audio from which can then be played and manipulated.

For more details about media element audio source nodes, check out the MediaElementAudioSourceNode reference page.

句法

var audioCtx = new AudioContext();
var source = audioCtx.createMediaElementSource(myMediaElement);

参数

myMediaElement: HTMLMediaElement object that you want to feed into an audio processing graph to manipulate.

A MediaElementAudioSourceNode .

范例

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.

注意 : You can also view this example running live ，或 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);

注意 : 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.

规范

规范	状态	注释
Web 音频 API The definition of 'createMediaElementSource()' 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
`createMediaElementSource`	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

另请参阅

使用 Web 音频 API

元数据

最后修改： 2020 年 1 月 22 日

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

在此页

句法

参数

返回

范例

规范

浏览器兼容性

图例

另请参阅

相关话题