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diff --git a/doc/html/probe.html b/doc/html/probe.html index 52ba570..ef7ba41 100644 --- a/doc/html/probe.html +++ b/doc/html/probe.html @@ -8,8 +8,9 @@ <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 1.4.4 --> -<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> +<!-- Generated by Doxygen 1.5.8 --> +<div class="contents"> +<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">// audioprobe.cpp</span> <span class="preprocessor">#include <iostream></span> @@ -17,42 +18,42 @@ <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#747ce2d73803641bbb66d6e78092aa1a" 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; + <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=1; i<=devices; i++ ) { - info = audio.<a class="code" href="classRtAudio.html#a4">getDeviceInfo</a>( i ); + info = audio.<a class="code" href="classRtAudio.html#02d7ff44ad1d7eae22283a052f3dfda8" 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#5bf008c629ef493c713ec870d0217407">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">": maximum output channels = "</span> << info.<a class="code" href="structRtAudio_1_1DeviceInfo.html#185f8aac1095de4fbb6e0076875d24c4">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">unsigned</span> <span class="keywordtype">int</span> outputChannels; <span class="comment">// Maximum output channels supported by device.</span> - <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> inputChannels; <span class="comment">// Maximum input channels supported by device.</span> - <span class="keywordtype">unsigned</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<unsigned 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> +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#5bf008c629ef493c713ec870d0217407">probed</a>; <span class="comment">// true if the device capabilities were successfully probed.</span> + std::string <a class="code" href="structRtAudio_1_1DeviceInfo.html#a0e2ea10c52c206c9e105ac76b01f194">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#185f8aac1095de4fbb6e0076875d24c4">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#731b31adf84c550ab98329be1baa58b4">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#ca6ecfb8b5b8c114c54809d8af50ee5b">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#af74fc23f451fdd22ed073a47f0db674">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#a8b03618fa1d4c051f6add14bb031728">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#5b158efcbfbd30e7226df92d0109d475">sampleRates</a>; <span class="comment">// Supported sample rates.</span> + <a class="code" href="RtAudio_8h.html#afca92882d25915560018873221e44b8" title="RtAudio data format type.">RtAudioFormat</a> <a class="code" href="structRtAudio_1_1DeviceInfo.html#97559ee4a1f2c8cfb765949e6193e1f4">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>; +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#afca92882d25915560018873221e44b8" 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> @@ -60,12 +61,13 @@ The following data formats are defined and fully supported by <a class="el" href <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> +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> +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> +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. </div> +<HR> <table><tr><td><img src="../images/mcgill.gif" width=165></td> - <td>©2001-2008 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>©2001-2009 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> |