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---
title: AudioNode
slug: Web/API/AudioNode
translation_of: Web/API/AudioNode
---
<p>{{ APIRef("Web Audio API") }}</p>
<p>A interface AudioNode é uma interface genérica para representar um módulo de processamento como uma fonte de áudio (ex. um elemento HTML {{HTMLElement("audio")}} ou {{HTMLElement("video")}} , um {{domxref("OscillatorNode")}}, etc.), um destino do áudio, um módulo intermediário de processamento (ex. um filtro como {{domxref("BiquadFilterNode")}} ou {{domxref("ConvolverNode")}}), ou um controle de volume (como o {{domxref("GainNode")}}).</p>
<p><img alt="AudioNodes participating in an AudioContext create a audio routing graph." src="https://mdn.mozillademos.org/files/12535/WebAudioBasicspt-br.png" style="display: block; height: 461px; margin: 0px auto; width: 677px;"></p>
<p>Um <code>AudioNode</code> tem entradas (inputs) e saídas (outputs), cada uma delas com uma determinada quantidade de canais. Um <code>AudioNode</code> sem nenhuma entrada e uma ou múltiplas saídas é chamado de <em>source node</em>. The exact processing done varies from one <code>AudioNode</code> to another but, in general, a node reads its inputs, does some audio-related processing, and generates new values for its outputs, or simply lets the audio pass through (for example in the {{domxref("AnalyserNode")}}, where the result of the processing is accessed separately).</p>
<p>Different nodes can be linked together to build a <em>processing graph</em>. Such a graph is contained in an {{domxref("AudioContext")}}. Each <code>AudioNode</code> participates in exactly one such context. In general, processing nodes inherit the properties and methods of <code>AudioNode</code>, but also define their own functionality on top. See the individual node pages for more details, as listed on the <a href="/en-US/docs/Web/API/Web_Audio_API">Web Audio API</a> homepage.</p>
<div class="note">
<p><strong>Note</strong>: An <code>AudioNode</code> can be target of events, therefore it implements the {{domxref("EventTarget")}} interface.</p>
</div>
<h2 id="Properties" style="">Properties</h2>
<dl>
<dt>{{domxref("AudioNode.context")}} {{readonlyInline}}</dt>
<dd>Returns the associated {{domxref("AudioContext")}}, that is the object representing the processing graph the node is participating in.</dd>
</dl>
<dl>
<dt>{{domxref("AudioNode.numberOfInputs")}} {{readonlyInline}}</dt>
<dd>Returns the number of inputs feeding the node. Source nodes are defined as nodes having a <code>numberOfInputs</code> property with a value of <code>0</code>.</dd>
</dl>
<dl>
<dt>{{domxref("AudioNode.numberOfOutputs")}} {{readonlyInline}}</dt>
<dd>Returns the number of outputs coming out of the node. Destination nodes — like {{ domxref("AudioDestinationNode") }} — have a value of <code>0</code> for this attribute.</dd>
</dl>
<dl>
<dt>{{domxref("AudioNode.channelCount")}}</dt>
<dd>Represents an integer used to determine how many channels are used when <a href="/en-US/docs/Web/API/Web_Audio_API/Basic_concepts_behind_Web_Audio_API#Up-mixing_and_down-mixing">up-mixing and down-mixing</a> connections to any inputs to the node. Its usage and precise definition depend on the value of {{domxref("AudioNode.channelCountMode")}}.</dd>
</dl>
<dl>
<dt>{{domxref("AudioNode.channelCountMode")}}</dt>
<dd>Represents an enumerated value describing the way channels must be matched between the node's inputs and outputs.</dd>
<dt>{{domxref("AudioNode.channelInterpretation")}}</dt>
<dd>Represents an enumerated value describing the meaning of the channels. This interpretation will define how audio <a href="/en-US/docs/Web/API/Web_Audio_API/Basic_concepts_behind_Web_Audio_API#Up-mixing_and_down-mixing">up-mixing and down-mixing</a> will happen.<br>
The possible values are <code>"speakers"</code> or <code>"discrete"</code>.</dd>
</dl>
<h2 id="Methods">Methods</h2>
<p><em>Also implements methods from the interface </em>{{domxref("EventTarget")}}.</p>
<dl>
<dt>{{domxref("AudioNode.connect(AudioNode)")}}</dt>
<dd>Allows us to connect one output of this node to one input of another node.</dd>
<dt>{{domxref("AudioNode.connect(AudioParam)")}}</dt>
<dd>Allows us to connect one output of this node to one input of an audio parameter.</dd>
<dt>{{domxref("AudioNode.disconnect()")}}</dt>
<dd>Allows us to disconnect the current node from another one it is already connected to.</dd>
</dl>
<h2 id="Example">Example</h2>
<p>This simple snippet of code shows the creation of some audio nodes, and how the <code>AudioNode</code> properties and methods can be used. You can find examples of such usage on any of the examples linked to on the <a href="/en-US/docs/Web/API/Web_Audio_API">Web Audio API</a> landing page (for example <a href="https://github.com/mdn/violent-theremin">Violent Theremin</a>.)<span class="p"> </span></p>
<pre class="brush: js;highlight[8,9,11,12,13,14]">var AudioContext = window.AudioContext || window.webkitAudioContext;
var audioCtx = new AudioContext();
var oscillator = audioCtx.createOscillator();
var gainNode = audioCtx.createGain();
oscillator.connect(gainNode);
gainNode.connect(audioCtx.destination);
oscillator.context;
oscillator.numberOfInputs;
oscillator.numberOfOutputs;
oscillator.channelCount;</pre>
<h2 id="Specifications">Specifications</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', '#the-audionode-interface', 'AudioNode')}}</td>
<td>{{Spec2('Web Audio API')}}</td>
<td> </td>
</tr>
</tbody>
</table>
<h2 id="Browser_compatibility">Compatibilidade com navegadores</h2>
<div>{{CompatibilityTable}}</div>
<div id="compat-desktop">
<table class="compat-table">
<tbody>
<tr>
<th>Feature</th>
<th>Chrome</th>
<th>Firefox (Gecko)</th>
<th>Internet Explorer</th>
<th>Opera</th>
<th>Safari (WebKit)</th>
</tr>
<tr>
<td>Basic support</td>
<td>{{CompatChrome(10.0)}}{{property_prefix("webkit")}}</td>
<td>{{CompatGeckoDesktop(25.0)}}</td>
<td>{{CompatNo}}</td>
<td>15.0{{property_prefix("webkit")}}<br>
22 (unprefixed)</td>
<td>{{CompatVersionUnknown}}</td>
</tr>
<tr>
<td><code>channelCount</code> <code>channelCountMode</code></td>
<td>{{CompatVersionUnknown}} {{property_prefix("webkit")}}</td>
<td>{{CompatVersionUnknown}}</td>
<td>{{CompatNo}}</td>
<td>{{CompatVersionUnknown}}</td>
<td>{{CompatNo}}</td>
</tr>
<tr>
<td><code>connect</code><code>(AudioParam)</code></td>
<td>{{CompatVersionUnknown}} {{property_prefix("webkit")}}</td>
<td>{{CompatVersionUnknown}}</td>
<td>{{CompatNo}}</td>
<td>{{CompatVersionUnknown}}</td>
<td>{{CompatNo}}</td>
</tr>
</tbody>
</table>
</div>
<div id="compat-mobile">
<table class="compat-table">
<tbody>
<tr>
<th>Feature</th>
<th>Android</th>
<th>Firefox Mobile (Gecko)</th>
<th>Firefox OS (Gecko)</th>
<th>IE Phone</th>
<th>Opera Mobile</th>
<th>Safari Mobile</th>
</tr>
<tr>
<td>Basic support</td>
<td>{{CompatUnknown}}</td>
<td>25.0</td>
<td>1.2</td>
<td>{{CompatUnknown}}</td>
<td>{{CompatUnknown}}</td>
<td>{{CompatUnknown}}</td>
</tr>
<tr>
<td><code>channelCount</code><br>
<code>channelCountMode</code></td>
<td>{{CompatNo}}</td>
<td>{{CompatVersionUnknown}}</td>
<td>{{CompatVersionUnknown}}</td>
<td>{{CompatNo}}</td>
<td>{{CompatNo}}</td>
<td>{{CompatNo}}</td>
</tr>
<tr>
<td><code>connect</code><code>(AudioParam)</code></td>
<td>{{CompatNo}}</td>
<td>{{CompatVersionUnknown}}</td>
<td>{{CompatVersionUnknown}}</td>
<td>{{CompatNo}}</td>
<td>{{CompatNo}}</td>
<td>{{CompatNo}}</td>
</tr>
</tbody>
</table>
</div>
<h2 id="See_also">See also</h2>
<ul>
<li><a href="/en-US/docs/Web/API/Web_Audio_API/Using_Web_Audio_API">Using the Web Audio API</a></li>
</ul>
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