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 <div class="title">oboe::AudioStreamDataCallback Class Reference<span class="mlabels"><span class="mlabel">abstract</span></span></div>  </div>
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 <p><code>#include &lt;<a class="el" href="_audio_stream_callback_8h_source.html">AudioStreamCallback.h</a>&gt;</code></p>
 <div class="dynheader">
 Inheritance diagram for oboe::AudioStreamDataCallback:</div>
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 <table class="memberdecls">
 <tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="pub-methods"></a>
 Public Member Functions</h2></td></tr>
 <tr class="memitem:ad8a3a9f609df5fd3a5d885cbe1b2204d"><td class="memItemLeft" align="right" valign="top">virtual <a class="el" href="namespaceoboe.html#af85fc9910a287df6c5df0ed396bb75cd">DataCallbackResult</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="classoboe_1_1_audio_stream_data_callback.html#ad8a3a9f609df5fd3a5d885cbe1b2204d">onAudioReady</a> (<a class="el" href="classoboe_1_1_audio_stream.html">AudioStream</a> *audioStream, void *audioData, int32_t numFrames)=0</td></tr>
 <tr class="separator:ad8a3a9f609df5fd3a5d885cbe1b2204d"><td class="memSeparator" colspan="2">&#160;</td></tr>
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 <a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
 <div class="textblock"><p><a class="el" href="classoboe_1_1_audio_stream_data_callback.html">AudioStreamDataCallback</a> defines a callback interface for moving data to/from an audio stream using <code>onAudioReady</code> 2) being alerted when a stream has an error using <code>onError*</code> methods</p>
 <p>It is used with <a class="el" href="classoboe_1_1_audio_stream_builder.html#acad307720e0f370267b4e2f9a626ae70">AudioStreamBuilder::setDataCallback()</a>. </p>
 </div><h2 class="groupheader">Member Function Documentation</h2>
 <a id="ad8a3a9f609df5fd3a5d885cbe1b2204d"></a>
 <h2 class="memtitle"><span class="permalink"><a href="#ad8a3a9f609df5fd3a5d885cbe1b2204d">&#9670;&nbsp;</a></span>onAudioReady()</h2>

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           <td class="memname">virtual <a class="el" href="namespaceoboe.html#af85fc9910a287df6c5df0ed396bb75cd">DataCallbackResult</a> oboe::AudioStreamDataCallback::onAudioReady </td>
           <td>(</td>
           <td class="paramtype"><a class="el" href="classoboe_1_1_audio_stream.html">AudioStream</a> *&#160;</td>
           <td class="paramname"><em>audioStream</em>, </td>
         </tr>
         <tr>
           <td class="paramkey"></td>
           <td></td>
           <td class="paramtype">void *&#160;</td>
           <td class="paramname"><em>audioData</em>, </td>
         </tr>
         <tr>
           <td class="paramkey"></td>
           <td></td>
           <td class="paramtype">int32_t&#160;</td>
           <td class="paramname"><em>numFrames</em>&#160;</td>
         </tr>
         <tr>
           <td></td>
           <td>)</td>
           <td></td><td></td>
         </tr>
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 <p>A buffer is ready for processing.</p>
 <p>For an output stream, this function should render and write numFrames of data in the stream's current data format to the audioData buffer.</p>
 <p>For an input stream, this function should read and process numFrames of data from the audioData buffer.</p>
 <p>The audio data is passed through the buffer. So do NOT call read() or write() on the stream that is making the callback.</p>
 <p>Note that numFrames can vary unless <a class="el" href="classoboe_1_1_audio_stream_builder.html#a3f397821f61eabaeedaf31064c859a54">AudioStreamBuilder::setFramesPerCallback()</a> is called.</p>
 <p>Also note that this callback function should be considered a "real-time" function. It must not do anything that could cause an unbounded delay because that can cause the audio to glitch or pop.</p>
 <p>These are things the function should NOT do: </p><ul>
 <li>
 allocate memory using, for example, malloc() or new </li>
 <li>
 any file operations such as opening, closing, reading or writing </li>
 <li>
 any network operations such as streaming </li>
 <li>
 use any mutexes or other synchronization primitives </li>
 <li>
 sleep </li>
 <li>
 oboeStream-&gt;stop(), pause(), flush() or close() </li>
 <li>
 oboeStream-&gt;read() </li>
 <li>
 oboeStream-&gt;write() </li>
 </ul>
 <p>The following are OK to call from the data callback: </p><ul>
 <li>
 oboeStream-&gt;get*() </li>
 <li>
 <a class="el" href="namespaceoboe.html#af65aaea3c5d82eee6906664d61c094b3">oboe::convertToText()</a> </li>
 <li>
 oboeStream-&gt;setBufferSizeInFrames() </li>
 </ul>
 <p>If you need to move data, eg. MIDI commands, in or out of the callback function then we recommend the use of non-blocking techniques such as an atomic FIFO.</p>
 <dl class="params"><dt>Parameters</dt><dd>
   <table class="params">
     <tr><td class="paramname">audioStream</td><td>pointer to the associated stream </td></tr>
     <tr><td class="paramname">audioData</td><td>buffer containing input data or a place to put output data </td></tr>
     <tr><td class="paramname">numFrames</td><td>number of frames to be processed </td></tr>
   </table>
   </dd>
 </dl>
 <dl class="section return"><dt>Returns</dt><dd>DataCallbackResult::Continue or DataCallbackResult::Stop </dd></dl>

 <p>Implemented in <a class="el" href="classoboe_1_1_stabilized_callback.html#ad447e12ebf732cf151655c1fbaf58a49">oboe::StabilizedCallback</a>.</p>

 </div>
 </div>
 <hr/>The documentation for this class was generated from the following file:<ul>
 <li>include/oboe/<a class="el" href="_audio_stream_callback_8h_source.html">AudioStreamCallback.h</a></li>
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	<p><code>#include <<a class="el" href="_audio_stream_callback_8h_source.html">AudioStreamCallback.h</a>></code></p>
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	Inheritance diagram for oboe::AudioStreamDataCallback:</div>
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	Public Member Functions</h2></td></tr>
	<tr class="memitem:ad8a3a9f609df5fd3a5d885cbe1b2204d"><td class="memItemLeft" align="right" valign="top">virtual <a class="el" href="namespaceoboe.html#af85fc9910a287df6c5df0ed396bb75cd">DataCallbackResult</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="classoboe_1_1_audio_stream_data_callback.html#ad8a3a9f609df5fd3a5d885cbe1b2204d">onAudioReady</a> (<a class="el" href="classoboe_1_1_audio_stream.html">AudioStream</a> audioStream, void audioData, int32_t numFrames)=0</td></tr>
	<tr class="separator:ad8a3a9f609df5fd3a5d885cbe1b2204d"><td class="memSeparator" colspan="2"> </td></tr>
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	<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
	<div class="textblock"><p><a class="el" href="classoboe_1_1_audio_stream_data_callback.html">AudioStreamDataCallback</a> defines a callback interface for moving data to/from an audio stream using <code>onAudioReady</code> 2) being alerted when a stream has an error using <code>onError*</code> methods</p>
	<p>It is used with <a class="el" href="classoboe_1_1_audio_stream_builder.html#acad307720e0f370267b4e2f9a626ae70">AudioStreamBuilder::setDataCallback()</a>. </p>
	</div><h2 class="groupheader">Member Function Documentation</h2>
	<a id="ad8a3a9f609df5fd3a5d885cbe1b2204d"></a>
	<h2 class="memtitle"><span class="permalink"><a href="#ad8a3a9f609df5fd3a5d885cbe1b2204d">◆ </a></span>onAudioReady()</h2>

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	<td class="memname">virtual <a class="el" href="namespaceoboe.html#af85fc9910a287df6c5df0ed396bb75cd">DataCallbackResult</a> oboe::AudioStreamDataCallback::onAudioReady </td>
	<td>(</td>
	<td class="paramtype"><a class="el" href="classoboe_1_1_audio_stream.html">AudioStream</a> * </td>
	<td class="paramname"><em>audioStream</em>, </td>
	</tr>
	<tr>
	<td class="paramkey"></td>
	<td></td>
	<td class="paramtype">void * </td>
	<td class="paramname"><em>audioData</em>, </td>
	</tr>
	<tr>
	<td class="paramkey"></td>
	<td></td>
	<td class="paramtype">int32_t </td>
	<td class="paramname"><em>numFrames</em> </td>
	</tr>
	<tr>
	<td></td>
	<td>)</td>
	<td></td><td></td>
	</tr>
	</table>
	</td>
	<td class="mlabels-right">
	<span class="mlabels"><span class="mlabel">pure virtual</span></span> </td>
	</tr>
	</table>
	</div><div class="memdoc">
	<p>A buffer is ready for processing.</p>
	<p>For an output stream, this function should render and write numFrames of data in the stream's current data format to the audioData buffer.</p>
	<p>For an input stream, this function should read and process numFrames of data from the audioData buffer.</p>
	<p>The audio data is passed through the buffer. So do NOT call read() or write() on the stream that is making the callback.</p>
	<p>Note that numFrames can vary unless <a class="el" href="classoboe_1_1_audio_stream_builder.html#a3f397821f61eabaeedaf31064c859a54">AudioStreamBuilder::setFramesPerCallback()</a> is called.</p>
	<p>Also note that this callback function should be considered a "real-time" function. It must not do anything that could cause an unbounded delay because that can cause the audio to glitch or pop.</p>
	<p>These are things the function should NOT do: </p><ul>
	<li>
	allocate memory using, for example, malloc() or new </li>
	<li>
	any file operations such as opening, closing, reading or writing </li>
	<li>
	any network operations such as streaming </li>
	<li>
	use any mutexes or other synchronization primitives </li>
	<li>
	sleep </li>
	<li>
	oboeStream->stop(), pause(), flush() or close() </li>
	<li>
	oboeStream->read() </li>
	<li>
	oboeStream->write() </li>
	</ul>
	<p>The following are OK to call from the data callback: </p><ul>
	<li>
	oboeStream->get*() </li>
	<li>
	<a class="el" href="namespaceoboe.html#af65aaea3c5d82eee6906664d61c094b3">oboe::convertToText()</a> </li>
	<li>
	oboeStream->setBufferSizeInFrames() </li>
	</ul>
	<p>If you need to move data, eg. MIDI commands, in or out of the callback function then we recommend the use of non-blocking techniques such as an atomic FIFO.</p>
	<dl class="params"><dt>Parameters</dt><dd>
	<table class="params">
	<tr><td class="paramname">audioStream</td><td>pointer to the associated stream </td></tr>
	<tr><td class="paramname">audioData</td><td>buffer containing input data or a place to put output data </td></tr>
	<tr><td class="paramname">numFrames</td><td>number of frames to be processed </td></tr>
	</table>
	</dd>
	</dl>
	<dl class="section return"><dt>Returns</dt><dd>DataCallbackResult::Continue or DataCallbackResult::Stop </dd></dl>

	<p>Implemented in <a class="el" href="classoboe_1_1_stabilized_callback.html#ad447e12ebf732cf151655c1fbaf58a49">oboe::StabilizedCallback</a>.</p>

	</div>
	</div>
	<hr/>The documentation for this class was generated from the following file:<ul>
	<li>include/oboe/<a class="el" href="_audio_stream_callback_8h_source.html">AudioStreamCallback.h</a></li>
	</ul>
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