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-<!-- Generated by Doxygen 1.4.4 -->
-<h1><a class="anchor" name="probe">Probing Device Capabilities</a></h1>A programmer may wish to query the available audio device capabilities before deciding which to use. The following example outlines how this can be done.<p>
-<div class="fragment"><pre class="fragment"><span class="comment">// probe.cpp</span>
+<!-- Generated by Doxygen 1.6.2 -->
+<div class="contents">
+
+
+<h1><a class="anchor" id="probe">Probing Device Capabilities </a></h1><p>A programmer may wish to query the available audio device capabilities before deciding which to use. The following example outlines how this can be done.</p>
+<div class="fragment"><pre class="fragment"><span class="comment">// audioprobe.cpp</span>
<span class="preprocessor">#include <iostream></span>
-<span class="preprocessor">#include "<a class="code" href="RtAudio_8h.html">RtAudio.h</a>"</span>
+<span class="preprocessor">#include "<a class="code" href="RtAudio_8h.html">RtAudio.h</a>"</span>
<span class="keywordtype">int</span> main()
{
- <a class="code" href="classRtAudio.html">RtAudio</a> audio;
+ <a class="code" href="classRtAudio.html" title="Realtime audio i/o C++ classes.">RtAudio</a> audio;
<span class="comment">// Determine the number of devices available</span>
- <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> devices = audio.<a class="code" href="classRtAudio.html#a3">getDeviceCount</a>();
+ <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> devices = audio.<a class="code" href="classRtAudio.html#a747ce2d73803641bbb66d6e78092aa1a" title="A public function that queries for the number of audio devices available.">getDeviceCount</a>();
<span class="comment">// Scan through devices for various capabilities</span>
- <a class="code" href="structRtAudio_1_1DeviceInfo.html">RtAudio::DeviceInfo</a> info;
- <span class="keywordflow">for</span> ( <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> i=1; i<=devices; i++ ) {
+ <a class="code" href="structRtAudio_1_1DeviceInfo.html" title="The public device information structure for returning queried values.">RtAudio::DeviceInfo</a> info;
+ <span class="keywordflow">for</span> ( <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> i=0; i<=devices; i++ ) {
- info = audio.<a class="code" href="classRtAudio.html#a4">getDeviceInfo</a>( i );
+ info = audio.<a class="code" href="classRtAudio.html#a02d7ff44ad1d7eae22283a052f3dfda8" title="Return an RtAudio::DeviceInfo structure for a specified device number.">getDeviceInfo</a>( i );
- <span class="keywordflow">if</span> ( info.<a class="code" href="structRtAudio_1_1DeviceInfo.html#o0">probed</a> == <span class="keyword">true</span> ) {
+ <span class="keywordflow">if</span> ( info.<a class="code" href="structRtAudio_1_1DeviceInfo.html#a97573717ccb1e75a834a0a108cd6982d">probed</a> == <span class="keyword">true</span> ) {
<span class="comment">// Print, for example, the maximum number of output channels for each device</span>
- std::cout << <span class="stringliteral">"device = "</span> << i;
- std::cout << <span class="stringliteral">": maximum output channels = "</span> << info.<a class="code" href="structRtAudio_1_1DeviceInfo.html#o2">outputChannels</a> << <span class="stringliteral">"\n"</span>;
+ std::cout << <span class="stringliteral">"device = "</span> << i;
+ std::cout << <span class="stringliteral">": maximum output channels = "</span> << info.<a class="code" href="structRtAudio_1_1DeviceInfo.html#a81aaf488f8158ef55b1bb678f66feb7d">outputChannels</a> << <span class="stringliteral">"\n"</span>;
}
}
<span class="keywordflow">return</span> 0;
}
-</pre></div><p>
-The <a class="el" href="structRtAudio_1_1DeviceInfo.html">RtAudio::DeviceInfo</a> structure is defined in <a class="el" href="RtAudio_8h.html">RtAudio.h</a> and provides a variety of information useful in assessing the capabilities of a device:<p>
-<div class="fragment"><pre class="fragment"> <span class="keyword">typedef</span> <span class="keyword">struct </span><a class="code" href="structRtAudio_1_1DeviceInfo.html">RtAudio::DeviceInfo</a> {
- <span class="keywordtype">bool</span> probed; <span class="comment">// true if the device capabilities were successfully probed.</span>
- std::string name; <span class="comment">// Character string device identifier.</span>
- <span class="keywordtype">int</span> outputChannels; <span class="comment">// Maximum output channels supported by device.</span>
- <span class="keywordtype">int</span> inputChannels; <span class="comment">// Maximum input channels supported by device.</span>
- <span class="keywordtype">int</span> duplexChannels; <span class="comment">// Maximum simultaneous input/output channels supported by device.</span>
- <span class="keywordtype">bool</span> isDefaultOutput; <span class="comment">// true if this is the default output device.</span>
- <span class="keywordtype">bool</span> isDefaultInput; <span class="comment">// true if this is the default input device.</span>
- std::vector<int> sampleRates; <span class="comment">// Supported sample rates.</span>
- <a class="code" href="RtAudio_8h.html#a1">RtAudioFormat</a> nativeFormats; <span class="comment">// Bit mask of supported data formats.</span>
+</pre></div><p>The <a class="el" href="structRtAudio_1_1DeviceInfo.html" title="The public device information structure for returning queried values.">RtAudio::DeviceInfo</a> structure is defined in <a class="el" href="RtAudio_8h.html">RtAudio.h</a> and provides a variety of information useful in assessing the capabilities of a device:</p>
+<div class="fragment"><pre class="fragment"> <span class="keyword">typedef</span> <span class="keyword">struct </span><a class="code" href="structRtAudio_1_1DeviceInfo.html" title="The public device information structure for returning queried values.">RtAudio::DeviceInfo</a> {
+ <span class="keywordtype">bool</span> <a class="code" href="structRtAudio_1_1DeviceInfo.html#a97573717ccb1e75a834a0a108cd6982d">probed</a>; <span class="comment">// true if the device capabilities were successfully probed.</span>
+ std::string <a class="code" href="structRtAudio_1_1DeviceInfo.html#a24df596ab8d54f2eb540c7cf16212b3b">name</a>; <span class="comment">// Character string device identifier.</span>
+ <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> <a class="code" href="structRtAudio_1_1DeviceInfo.html#a81aaf488f8158ef55b1bb678f66feb7d">outputChannels</a>; <span class="comment">// Maximum output channels supported by device.</span>
+ <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> <a class="code" href="structRtAudio_1_1DeviceInfo.html#a56247b458a937ae84d98ca9c4b243275">inputChannels</a>; <span class="comment">// Maximum input channels supported by device.</span>
+ <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> <a class="code" href="structRtAudio_1_1DeviceInfo.html#a3e8ad34c2d14e24293a0beafc26186e7">duplexChannels</a>; <span class="comment">// Maximum simultaneous input/output channels supported by device.</span>
+ <span class="keywordtype">bool</span> <a class="code" href="structRtAudio_1_1DeviceInfo.html#a5365245e73ffe29a05734de4474acd58">isDefaultOutput</a>; <span class="comment">// true if this is the default output device.</span>
+ <span class="keywordtype">bool</span> <a class="code" href="structRtAudio_1_1DeviceInfo.html#a7c8aca084bd908799b6be5954b80def2">isDefaultInput</a>; <span class="comment">// true if this is the default input device.</span>
+ std::vector<unsigned int> <a class="code" href="structRtAudio_1_1DeviceInfo.html#afa65f5f92f66ce7aacd3ff35e11b230f">sampleRates</a>; <span class="comment">// Supported sample rates.</span>
+ <a class="code" href="RtAudio_8h.html#aafca92882d25915560018873221e44b8" title="RtAudio data format type.">RtAudioFormat</a> <a class="code" href="structRtAudio_1_1DeviceInfo.html#a23251b549b89b2fe04a57fcd7cb76ea4">nativeFormats</a>; <span class="comment">// Bit mask of supported data formats.</span>
};
-</pre></div><p>
-The following data formats are defined and fully supported by <a class="el" href="classRtAudio.html">RtAudio</a>:<p>
-<div class="fragment"><pre class="fragment"> <span class="keyword">typedef</span> <span class="keywordtype">unsigned</span> <span class="keywordtype">long</span> <a class="code" href="RtAudio_8h.html#a1">RtAudioFormat</a>;
+</pre></div><p>The following data formats are defined and fully supported by <a class="el" href="classRtAudio.html" title="Realtime audio i/o C++ classes.">RtAudio</a>:</p>
+<div class="fragment"><pre class="fragment"> <span class="keyword">typedef</span> <span class="keywordtype">unsigned</span> <span class="keywordtype">long</span> <a class="code" href="RtAudio_8h.html#aafca92882d25915560018873221e44b8" title="RtAudio data format type.">RtAudioFormat</a>;
<span class="keyword">static</span> <span class="keyword">const</span> RtAudioFormat RTAUDIO_SINT8; <span class="comment">// Signed 8-bit integer</span>
<span class="keyword">static</span> <span class="keyword">const</span> RtAudioFormat RTAUDIO_SINT16; <span class="comment">// Signed 16-bit integer</span>
<span class="keyword">static</span> <span class="keyword">const</span> RtAudioFormat RTAUDIO_SINT24; <span class="comment">// Signed 24-bit integer (lower 3 bytes of 32-bit signed integer.)</span>
<span class="keyword">static</span> <span class="keyword">const</span> RtAudioFormat RTAUDIO_SINT32; <span class="comment">// Signed 32-bit integer</span>
<span class="keyword">static</span> <span class="keyword">const</span> RtAudioFormat RTAUDIO_FLOAT32; <span class="comment">// 32-bit float normalized between +/- 1.0</span>
<span class="keyword">static</span> <span class="keyword">const</span> RtAudioFormat RTAUDIO_FLOAT64; <span class="comment">// 64-bit double normalized between +/- 1.0</span>
-</pre></div><p>
-The <code>nativeFormats</code> member of the <a class="el" href="structRtAudio_1_1DeviceInfo.html">RtAudio::DeviceInfo</a> structure is a bit mask of the above formats which are natively supported by the device. However, <a class="el" href="classRtAudio.html">RtAudio</a> will automatically provide format conversion if a particular format is not natively supported. When the <code>probed</code> member of the <a class="el" href="structRtAudio_1_1DeviceInfo.html">RtAudio::DeviceInfo</a> structure is false, the remaining structure members are undefined and the device is probably unusable.<p>
-Some audio devices may require a minimum channel value greater than one. <a class="el" href="classRtAudio.html">RtAudio</a> will provide automatic channel number compensation when the number of channels set by the user is less than that required by the device. Channel compensation is <em>NOT</em> possible when the number of channels set by the user is greater than that supported by the device.<p>
-It should be noted that the capabilities reported by a device driver or underlying audio API are not always accurate and/or may be dependent on a combination of device settings. For this reason, <a class="el" href="classRtAudio.html">RtAudio</a> does not rely on the queried values when attempting to open a stream. <HR>
+</pre></div><p>The <code>nativeFormats</code> member of the <a class="el" href="structRtAudio_1_1DeviceInfo.html" title="The public device information structure for returning queried values.">RtAudio::DeviceInfo</a> structure is a bit mask of the above formats which are natively supported by the device. However, <a class="el" href="classRtAudio.html" title="Realtime audio i/o C++ classes.">RtAudio</a> will automatically provide format conversion if a particular format is not natively supported. When the <code>probed</code> member of the <a class="el" href="structRtAudio_1_1DeviceInfo.html" title="The public device information structure for returning queried values.">RtAudio::DeviceInfo</a> structure is false, the remaining structure members are undefined and the device is probably unusable.</p>
+<p>Some audio devices may require a minimum channel value greater than one. <a class="el" href="classRtAudio.html" title="Realtime audio i/o C++ classes.">RtAudio</a> will provide automatic channel number compensation when the number of channels set by the user is less than that required by the device. Channel compensation is <em>NOT</em> possible when the number of channels set by the user is greater than that supported by the device.</p>
+<p>It should be noted that the capabilities reported by a device driver or underlying audio API are not always accurate and/or may be dependent on a combination of device settings. For this reason, <a class="el" href="classRtAudio.html" title="Realtime audio i/o C++ classes.">RtAudio</a> does not rely on the queried values when attempting to open a stream. </p>
+</div>
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