AudioContext.createBufferSource() - Web API 接口参考 编辑

createBufferSource() 方法用于创建一个新的AudioBufferSourceNode接口, 该接口可以通过AudioBuffer 对象来播放音频数据. AudioBuffer对象可以通过AudioContext.createBuffer 来创建或者通过 AudioContext.decodeAudioData成功解码音轨后获取.

语法

var audioCtx = new AudioContext();
var source = audioCtx.createBufferSource();

返回

一个AudioBufferSourceNode对象.

例子

在这个例子中, 我们将会创建一个2秒的缓冲器,并用白噪音填充它, 然后通过AudioBufferSourceNode来播放它. 

Note: You can also run the code live, or view the source.

var audioCtx = new (window.AudioContext || window.webkitAudioContext)();
var button = document.querySelector('button');
var pre = document.querySelector('pre');
var myScript = document.querySelector('script');

pre.innerHTML = myScript.innerHTML;

// Stereo
var channels = 2;
// Create an empty two second stereo buffer at the
// sample rate of the AudioContext
var frameCount = audioCtx.sampleRate * 2.0;

var myArrayBuffer = audioCtx.createBuffer(2, frameCount, audioCtx.sampleRate);

button.onclick = function() {
  // Fill the buffer with white noise;
  //just random values between -1.0 and 1.0
  for (var channel = 0; channel < channels; channel++) {
   // This gives us the actual ArrayBuffer that contains the data
   var nowBuffering = myArrayBuffer.getChannelData(channel);
   for (var i = 0; i < frameCount; i++) {
     // Math.random() is in [0; 1.0]
     // audio needs to be in [-1.0; 1.0]
     nowBuffering[i] = Math.random() * 2 - 1;
   }
  }

  // Get an AudioBufferSourceNode.
  // This is the AudioNode to use when we want to play an AudioBuffer
  var source = audioCtx.createBufferSource();
  // set the buffer in the AudioBufferSourceNode
  source.buffer = myArrayBuffer;
  // connect the AudioBufferSourceNode to the
  // destination so we can hear the sound
  source.connect(audioCtx.destination);
  // start the source playing
  source.start();
}

规范

Specification	Status	Comment
Web Audio API createBufferSource()	Working Draft

浏览器支持

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!

• Desktop
• Mobile

Feature	Chrome	Firefox (Gecko)	Internet Explorer	Opera	Safari (WebKit)
Basic support	10.0webkit	25.0 (25.0)	未实现	15.0webkit 22 (unprefixed)	6.0webkit

Feature	Android	Firefox Mobile (Gecko)	Firefox OS	IE Mobile	Opera Mobile	Safari Mobile	Chrome for Android
Basic support	?	26.0	1.2	?	?	?	33.0

See also

• Using the Web Audio API