docs/libs/html/gst-plugins-base-libs-gstaudiosink.html

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  20 <th width="100%" align="center">GStreamer Base Plugins 0.10 Library Reference Manual</th>
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  24 <a href="#gst-plugins-base-libs-gstaudiosink.synopsis" class="shortcut">Top</a>
  25                    |
  26                   <a href="#gst-plugins-base-libs-gstaudiosink.description" class="shortcut">Description</a>
  27                    |
  28                   <a href="#gst-plugins-base-libs-gstaudiosink.object-hierarchy" class="shortcut">Object Hierarchy</a>
  29 </td></tr>
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  31 <div class="refentry">
  32 <a name="gst-plugins-base-libs-gstaudiosink"></a><div class="titlepage"></div>
  33 <div class="refnamediv"><table width="100%"><tr>
  34 <td valign="top">
  35 <h2><span class="refentrytitle"><a name="gst-plugins-base-libs-gstaudiosink.top_of_page"></a>gstaudiosink</span></h2>
  36 <p>gstaudiosink — Simple base class for audio sinks</p>
  37 </td>
  38 <td valign="top" align="right"></td>
  39 </tr></table></div>
  40 <div class="refsynopsisdiv">
  41 <a name="gst-plugins-base-libs-gstaudiosink.synopsis"></a><h2>Synopsis</h2>
  42 <a name="GstAudioSink"></a><pre class="synopsis">
  43 #include &lt;gst/audio/gstaudiosink.h&gt;
  44
  45 struct              <a class="link" href="gst-plugins-base-libs-gstaudiosink.html#GstAudioSink-struct" title="struct GstAudioSink">GstAudioSink</a>;
  46 struct              <a class="link" href="gst-plugins-base-libs-gstaudiosink.html#GstAudioSinkClass" title="struct GstAudioSinkClass">GstAudioSinkClass</a>;
  47 </pre>
  48 </div>
  49 <div class="refsect1">
  50 <a name="gst-plugins-base-libs-gstaudiosink.object-hierarchy"></a><h2>Object Hierarchy</h2>
  51 <pre class="synopsis">
  52   <a href="http://library.gnome.org/devel/gobject/unstable/gobject-The-Base-Object-Type.html#GObject">GObject</a>
  53    +----<a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstObject.html">GstObject</a>
  54          +----<a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstElement.html">GstElement</a>
  55                +----<a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer-libs/html/GstBaseSink.html">GstBaseSink</a>
  56                      +----<a class="link" href="gst-plugins-base-libs-gstbaseaudiosink.html#GstBaseAudioSink">GstBaseAudioSink</a>
  57                            +----GstAudioSink
  58 </pre>
  59 </div>
  60 <div class="refsect1">
  61 <a name="gst-plugins-base-libs-gstaudiosink.description"></a><h2>Description</h2>
  62 <p>
  63 This is the most simple base class for audio sinks that only requires
  64 subclasses to implement a set of simple functions:
  65 </p>
  66 <p>
  67 </p>
  68 <div class="variablelist"><table border="0">
  69 <col align="left" valign="top">
  70 <tbody>
  71 <tr>
  72 <td><p><span class="term"><code class="function">open()</code></span></p></td>
  73 <td><p>Open the device.</p></td>
  74 </tr>
  75 <tr>
  76 <td><p><span class="term"><code class="function">prepare()</code></span></p></td>
  77 <td><p>Configure the device with the specified format.</p></td>
  78 </tr>
  79 <tr>
  80 <td><p><span class="term"><code class="function">write()</code></span></p></td>
  81 <td><p>Write samples to the device.</p></td>
  82 </tr>
  83 <tr>
  84 <td><p><span class="term"><code class="function">reset()</code></span></p></td>
  85 <td><p>Unblock writes and flush the device.</p></td>
  86 </tr>
  87 <tr>
  88 <td><p><span class="term"><code class="function">delay()</code></span></p></td>
  89 <td><p>Get the number of samples written but not yet played
  90     by the device.</p></td>
  91 </tr>
  92 <tr>
  93 <td><p><span class="term"><code class="function">unprepare()</code></span></p></td>
  94 <td><p>Undo operations done by prepare.</p></td>
  95 </tr>
  96 <tr>
  97 <td><p><span class="term"><code class="function">close()</code></span></p></td>
  98 <td><p>Close the device.</p></td>
  99 </tr>
 100 </tbody>
 101 </table></div>
 102 <p>
 103 </p>
 104 <p>
 105 All scheduling of samples and timestamps is done in this base class
 106 together with <a class="link" href="gst-plugins-base-libs-gstbaseaudiosink.html#GstBaseAudioSink"><span class="type">GstBaseAudioSink</span></a> using a default implementation of a
 107 <a class="link" href="gst-plugins-base-libs-gstringbuffer.html#GstRingBuffer"><span class="type">GstRingBuffer</span></a> that uses threads.
 108 </p>
 109 <p>
 110 Last reviewed on 2006-09-27 (0.10.12)
 111 </p>
 112 </div>
 113 <div class="refsect1">
 114 <a name="gst-plugins-base-libs-gstaudiosink.details"></a><h2>Details</h2>
 115 <div class="refsect2">
 116 <a name="GstAudioSink-struct"></a><h3>struct GstAudioSink</h3>
 117 <pre class="programlisting">struct GstAudioSink;</pre>
 118 <p>
 119 Opaque <a class="link" href="gst-plugins-base-libs-gstaudiosink.html#GstAudioSink"><span class="type">GstAudioSink</span></a>.
 120 </p>
 121 </div>
 122 <hr>
 123 <div class="refsect2">
 124 <a name="GstAudioSinkClass"></a><h3>struct GstAudioSinkClass</h3>
 125 <pre class="programlisting">struct GstAudioSinkClass {
 126   GstBaseAudioSinkClass parent_class;
 127
 128   /* vtable */
 129
 130   /* open the device with given specs */
 131   gboolean (*open)      (GstAudioSink *sink);
 132   /* prepare resources and state to operate with the given specs */
 133   gboolean (*prepare)   (GstAudioSink *sink, GstRingBufferSpec *spec);
 134   /* undo anything that was done in prepare() */
 135   gboolean (*unprepare) (GstAudioSink *sink);
 136   /* close the device */
 137   gboolean (*close)     (GstAudioSink *sink);
 138   /* write samples to the device */
 139   /* FIXME 0.11: change return value to gint, as most implementation use that
 140    * already anyway */
 141   guint    (*write)     (GstAudioSink *sink, gpointer data, guint length);
 142   /* get number of samples queued in the device */
 143   guint    (*delay)     (GstAudioSink *sink);
 144   /* reset the audio device, unblock from a write */
 145   void     (*reset)     (GstAudioSink *sink);
 146 };
 147 </pre>
 148 <p>
 149 <a class="link" href="gst-plugins-base-libs-gstaudiosink.html#GstAudioSink"><span class="type">GstAudioSink</span></a> class. Override the vmethods to implement functionality.
 150 </p>
 151 <div class="variablelist"><table border="0">
 152 <col align="left" valign="top">
 153 <tbody>
 154 <tr>
 155 <td><p><span class="term"><a class="link" href="gst-plugins-base-libs-gstbaseaudiosink.html#GstBaseAudioSinkClass" title="struct GstBaseAudioSinkClass"><span class="type">GstBaseAudioSinkClass</span></a> <em class="structfield"><code><a name="GstAudioSinkClass.parent-class"></a>parent_class</code></em>;</span></p></td>
 156 <td>the parent class structure.</td>
 157 </tr>
 158 <tr>
 159 <td><p><span class="term"><em class="structfield"><code><a name="GstAudioSinkClass.open"></a>open</code></em> ()</span></p></td>
 160 <td>Open the device. No configuration needs to be done at this point.
 161 This function is also used to check if the device is available.</td>
 162 </tr>
 163 <tr>
 164 <td><p><span class="term"><em class="structfield"><code><a name="GstAudioSinkClass.prepare"></a>prepare</code></em> ()</span></p></td>
 165 <td>Prepare the device to operate with the specified parameters.</td>
 166 </tr>
 167 <tr>
 168 <td><p><span class="term"><em class="structfield"><code><a name="GstAudioSinkClass.unprepare"></a>unprepare</code></em> ()</span></p></td>
 169 <td>Undo operations done in prepare.</td>
 170 </tr>
 171 <tr>
 172 <td><p><span class="term"><em class="structfield"><code><a name="GstAudioSinkClass.close"></a>close</code></em> ()</span></p></td>
 173 <td>Close the device.</td>
 174 </tr>
 175 <tr>
 176 <td><p><span class="term"><em class="structfield"><code><a name="GstAudioSinkClass.write"></a>write</code></em> ()</span></p></td>
 177 <td>Write data to the device.</td>
 178 </tr>
 179 <tr>
 180 <td><p><span class="term"><em class="structfield"><code><a name="GstAudioSinkClass.delay"></a>delay</code></em> ()</span></p></td>
 181 <td>Return how many samples are still in the device. This is used to
 182 drive the synchronisation.</td>
 183 </tr>
 184 <tr>
 185 <td><p><span class="term"><em class="structfield"><code><a name="GstAudioSinkClass.reset"></a>reset</code></em> ()</span></p></td>
 186 <td>Returns as quickly as possible from a write and flush any pending
 187 samples from the device.</td>
 188 </tr>
 189 </tbody>
 190 </table></div>
 191 </div>
 192 </div>
 193 <div class="refsect1">
 194 <a name="gst-plugins-base-libs-gstaudiosink.see-also"></a><h2>See Also</h2>
 195 <a class="link" href="gst-plugins-base-libs-gstbaseaudiosink.html#GstBaseAudioSink"><span class="type">GstBaseAudioSink</span></a>, <a class="link" href="gst-plugins-base-libs-gstringbuffer.html#GstRingBuffer"><span class="type">GstRingBuffer</span></a>, <a class="link" href="gst-plugins-base-libs-gstaudiosink.html#GstAudioSink"><span class="type">GstAudioSink</span></a>.
 196 </div>
 197 </div>
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