AudioContext.createChannelMerger()

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since April 2021.

AudioContext.createChannelMerger() 方法，会创建一个 ChannelMergerNode，后者可以把多个音频流的通道整合到一个音频流。

语法

js
var audioCtx = new AudioContext();
var merger = audioCtx.createChannelMerger(2);

参数

numberOfInputs

通道输入音频流的数量，输出流将包含这个数量的通道。默认值 6。

返回值

一个 ChannelMergerNode.

示例

下面的例子展示了如何分离立体音轨（就是一段音乐），处理使左右声道不同。使用的时候，需要指定 AudioNode.connect(AudioNode) 方法的第二个和第三个参数，分别用来指定通道链接来源的索引和输出的索引。

js
var ac = new AudioContext();
ac.decodeAudioData(someStereoBuffer, function (data) {
  var source = ac.createBufferSource();
  source.buffer = data;
  var splitter = ac.createChannelSplitter(2);
  source.connect(splitter);
  var merger = ac.createChannelMerger(2);

  // Reduce the volume of the left channel only
  var gainNode = ac.createGain();
  gainNode.gain.value = 0.5;
  splitter.connect(gainNode, 0);

  // Connect the splitter back to the second input of the merger: we
  // effectively swap the channels, here, reversing the stereo image.
  gainNode.connect(merger, 0, 1);
  splitter.connect(merger, 1, 0);

  var dest = ac.createMediaStreamDestination();

  // Because we have used a ChannelMergerNode, we now have a stereo
  // MediaStream we can use to pipe the Web Audio graph to WebRTC,
  // MediaRecorder, etc.
  merger.connect(dest);
});

规范

Specification
Web Audio API
# dom-baseaudiocontext-createchannelmerger

浏览器兼容性

参见