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---
title: AudioContext.createChannelMerger()
slug: Web/API/BaseAudioContext/createChannelMerger
tags:
- API
- Audio
- AudioContext
- Audio_Chinese
translation_of: Web/API/BaseAudioContext/createChannelMerger
original_slug: Web/API/AudioContext/createChannelMerger
---
<p>{{ APIRef("Web Audio API") }}</p>
<div>
<p>AudioContext.<code>createChannelMerger()方法，会创建一个</code>ChannelMergerNode，后者可以把多个音频流的通道整合到一个音频流。</p>
</div>
<h2 id="语法">语法</h2>
<pre class="brush: js">var audioCtx = new AudioContext();
var merger = audioCtx.createChannelMerger(2);</pre>
<h3 id="参数">参数</h3>
<dl>
<dt>numberOfInputs</dt>
<dd>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。</dd>
</dl>
<h3 id="返回值">返回值</h3>
<p>一个 {{domxref("ChannelMergerNode")}}.</p>
<h2 id="（举个）栗（例）子">（举个）栗（例）子</h2>
<p>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。</p>
<pre class="brush: js;highlight[7,16,17,24]">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);
});</pre>
<h2 id="规范">规范</h2>
<table class="standard-table">
<tbody>
<tr>
<th scope="col">Specification</th>
<th scope="col">Status</th>
<th scope="col">Comment</th>
</tr>
<tr>
<td>{{SpecName('Web Audio API', '#widl-AudioContext-createChannelMerger-ChannelMergerNode-unsigned-long-numberOfInputs', 'createChannelMerger()')}}</td>
<td>{{Spec2('Web Audio API')}}</td>
<td> </td>
</tr>
</tbody>
</table>
<h2 id="浏览器兼容性">浏览器兼容性</h2>
{{Compat("api.BaseAudioContext.createChannelMerger")}}
<h2 id="相关页面">相关页面</h2>
<ul>
<li><a href="/en-US/docs/Web_Audio_API/Using_Web_Audio_API">Using the Web Audio API</a></li>
</ul>
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