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---
title: AudioContext.createWaveShaper()
slug: Web/API/BaseAudioContext/createWaveShaper
translation_of: Web/API/BaseAudioContext/createWaveShaper
original_slug: Web/API/AudioContext/createWaveShaper
---
<p>{{ APIRef("Web Audio API") }}</p>
<p>{{ domxref("AudioContext") }} 接口的createWaveShaper()方法创建了 表示非线性失真的{{ domxref("WaveShaperNode") }}。该节点通常被用来给音频添加失真效果</p>
<h2 id="语法">语法</h2>
<pre class="brush: js">var audioCtx = new AudioContext();
var distortion = audioCtx.createWaveShaper();</pre>
<h3 id="Description" name="Description">返回</h3>
<p>A {{domxref("WaveShaperNode")}}.</p>
<h2 id="Example" name="Example">例子</h2>
<p>The following example shows basic usage of an AudioContext to create a wave shaper node. For applied examples/information, check out our <a href="http://mdn.github.io/voice-change-o-matic/">Voice-change-O-matic</a><a href="http://mdn.github.io/voice-change-o-matic/"> demo</a> (<a href="https://github.com/mdn/voice-change-o-matic/blob/gh-pages/scripts/app.js">see app.js</a> for relevant code).</p>
<p>下面的例子展示了AudioContext创建一个波形整形器节点的基本用法。有关应用示例/信息，请查看我们的<a href="http://mdn.github.io/voice-change-o-matic/">oice-change-O-matic</a><a href="http://mdn.github.io/voice-change-o-matic/"> demo</a>演示（有关代码，请参阅<a href="https://github.com/mdn/voice-change-o-matic/blob/gh-pages/scripts/app.js">app.js</a>）。</p>
<div class="note">
<p><strong>注</strong>：实现失真曲线并不是简单的事情，你可能需要到处找资料来找到这样的算法。我们在<a href="http://stackoverflow.com/questions/22312841/waveshaper-node-in-webaudio-how-to-emulate-distortion">Stack Overflow</a>上找到了以下的失真曲线代码</p>
</div>
<pre class="brush: js">var audioCtx = new (window.AudioContext || window.webkitAudioContext)();
var distortion = audioCtx.createWaveShaper();
...
function makeDistortionCurve(amount) {
var k = typeof amount === 'number' ? amount : 50,
n_samples = 44100,
curve = new Float32Array(n_samples),
deg = Math.PI / 180,
i = 0,
x;
for ( ; i < n_samples; ++i ) {
x = i * 2 / n_samples - 1;
curve[i] = ( 3 + k ) * x * 20 * deg / ( Math.PI + k * Math.abs(x) );
}
return curve;
};
...
distortion.curve = makeDistortionCurve(400);
distortion.oversample = '4x';</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-createWaveShaper-WaveShaperNode', 'createWaveShaper()')}}</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.createWaveShaper")}}
<h2 id="See_also">See also</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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