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diff --git a/doc/html/probe.html b/doc/html/probe.html index c3ecc26..69fd84c 100644 --- a/doc/html/probe.html +++ b/doc/html/probe.html @@ -8,67 +8,68 @@ <CENTER> <a class="qindex" href="index.html">Home</a> <a class="qindex" href="annotated.html">Class/Enum List</a> <a class="qindex" href="files.html">File List</a> <a class="qindex" href="functions.html">Compound Members</a> </CENTER> <HR> -<!-- Generated by Doxygen 1.6.2 --> +<!-- Generated by Doxygen 1.8.2 --> +</div><!-- top --> +<div class="header"> + <div class="headertitle"> +<div class="title">Probing Device Capabilities </div> </div> +</div><!--header--> <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="keywordtype">int</span> main() -{ - <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#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" 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#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#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#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" 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" 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" 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> +<div class="textblock"><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"><div class="line"><span class="comment">// audioprobe.cpp</span></div> +<div class="line"></div> +<div class="line"><span class="preprocessor">#include <iostream></span></div> +<div class="line"><span class="preprocessor">#include "<a class="code" href="RtAudio_8h.html">RtAudio.h</a>"</span></div> +<div class="line"></div> +<div class="line"><span class="keywordtype">int</span> main()</div> +<div class="line">{</div> +<div class="line"> <a class="code" href="classRtAudio.html" title="Realtime audio i/o C++ classes.">RtAudio</a> audio;</div> +<div class="line"></div> +<div class="line"> <span class="comment">// Determine the number of devices available</span></div> +<div class="line"> <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>();</div> +<div class="line"></div> +<div class="line"> <span class="comment">// Scan through devices for various capabilities</span></div> +<div class="line"> <a class="code" href="structRtAudio_1_1DeviceInfo.html" title="The public device information structure for returning queried values.">RtAudio::DeviceInfo</a> info;</div> +<div class="line"> <span class="keywordflow">for</span> ( <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> i=0; i<=devices; i++ ) {</div> +<div class="line"></div> +<div class="line"> info = audio.<a class="code" href="classRtAudio.html#a02d7ff44ad1d7eae22283a052f3dfda8" title="Return an RtAudio::DeviceInfo structure for a specified device number.">getDeviceInfo</a>( i );</div> +<div class="line"></div> +<div class="line"> <span class="keywordflow">if</span> ( info.<a class="code" href="structRtAudio_1_1DeviceInfo.html#a97573717ccb1e75a834a0a108cd6982d">probed</a> == <span class="keyword">true</span> ) {</div> +<div class="line"> <span class="comment">// Print, for example, the maximum number of output channels for each device</span></div> +<div class="line"> std::cout << <span class="stringliteral">"device = "</span> << i;</div> +<div class="line"> 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>;</div> +<div class="line"> }</div> +<div class="line"> }</div> +<div class="line"></div> +<div class="line"> <span class="keywordflow">return</span> 0;</div> +<div class="line">}</div> +</div><!-- fragment --><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"><div class="line"><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> {</div> +<div class="line"> <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></div> +<div class="line"> std::string <a class="code" href="structRtAudio_1_1DeviceInfo.html#a24df596ab8d54f2eb540c7cf16212b3b">name</a>; <span class="comment">// Character string device identifier.</span></div> +<div class="line"> <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></div> +<div class="line"> <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></div> +<div class="line"> <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></div> +<div class="line"> <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></div> +<div class="line"> <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></div> +<div class="line"> std::vector<unsigned int> <a class="code" href="structRtAudio_1_1DeviceInfo.html#afa65f5f92f66ce7aacd3ff35e11b230f">sampleRates</a>; <span class="comment">// Supported sample rates.</span></div> +<div class="line"> <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></div> +<div class="line">};</div> +</div><!-- fragment --><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"><div class="line"><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>;</div> +<div class="line"><span class="keyword">static</span> <span class="keyword">const</span> RtAudioFormat RTAUDIO_SINT8; <span class="comment">// Signed 8-bit integer</span></div> +<div class="line"><span class="keyword">static</span> <span class="keyword">const</span> RtAudioFormat RTAUDIO_SINT16; <span class="comment">// Signed 16-bit integer</span></div> +<div class="line"><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></div> +<div class="line"><span class="keyword">static</span> <span class="keyword">const</span> RtAudioFormat RTAUDIO_SINT32; <span class="comment">// Signed 32-bit integer</span></div> +<div class="line"><span class="keyword">static</span> <span class="keyword">const</span> RtAudioFormat RTAUDIO_FLOAT32; <span class="comment">// 32-bit float normalized between +/- 1.0</span></div> +<div class="line"><span class="keyword">static</span> <span class="keyword">const</span> RtAudioFormat RTAUDIO_FLOAT64; <span class="comment">// 64-bit double normalized between +/- 1.0</span></div> +</div><!-- fragment --><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> +</div></div><!-- contents --> <HR> - <table><tr><td><img src="../images/mcgill.gif" width=165></td> - <td>©2001-2012 Gary P. Scavone, McGill University. All Rights Reserved.<br>Maintained by <a href="http://www.music.mcgill.ca/~gary/">Gary P. Scavone</a>.</td></tr> + <td>©2001-2013 Gary P. Scavone, McGill University. All Rights Reserved.<br>Maintained by <a href="http://www.music.mcgill.ca/~gary/">Gary P. Scavone</a>.</td></tr> </table> - </BODY> </HTML> |