1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> 2<html> 3<head> 4<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 5<title>GstAudioAggregator: GStreamer Base Plugins 1.0 Library Reference Manual</title> 6<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 7<link rel="home" href="index.html" title="GStreamer Base Plugins 1.0 Library Reference Manual"> 8<link rel="up" href="gstreamer-audio.html" title="Audio Library"> 9<link rel="prev" href="gst-plugins-base-libs-GstAudio-meta.html" title="GstAudio meta"> 10<link rel="next" href="GstAudioCdSrc.html" title="GstAudioCdSrc"> 11<meta name="generator" content="GTK-Doc V1.28 (XML mode)"> 12<link rel="stylesheet" href="style.css" type="text/css"> 13</head> 14<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 15<table class="navigation" id="top" width="100%" summary="Navigation header" cellpadding="2" cellspacing="5"><tr valign="middle"> 16<td width="100%" align="left" class="shortcuts"> 17<a href="#" class="shortcut">Top</a><span id="nav_description"> <span class="dim">|</span> 18 <a href="#GstAudioAggregator.description" class="shortcut">Description</a></span><span id="nav_hierarchy"> <span class="dim">|</span> 19 <a href="#GstAudioAggregator.object-hierarchy" class="shortcut">Object Hierarchy</a></span><span id="nav_properties"> <span class="dim">|</span> 20 <a href="#GstAudioAggregator.properties" class="shortcut">Properties</a></span> 21</td> 22<td><a accesskey="h" href="index.html"><img src="home.png" width="16" height="16" border="0" alt="Home"></a></td> 23<td><a accesskey="u" href="gstreamer-audio.html"><img src="up.png" width="16" height="16" border="0" alt="Up"></a></td> 24<td><a accesskey="p" href="gst-plugins-base-libs-GstAudio-meta.html"><img src="left.png" width="16" height="16" border="0" alt="Prev"></a></td> 25<td><a accesskey="n" href="GstAudioCdSrc.html"><img src="right.png" width="16" height="16" border="0" alt="Next"></a></td> 26</tr></table> 27<div class="refentry"> 28<a name="GstAudioAggregator"></a><div class="titlepage"></div> 29<div class="refnamediv"><table width="100%"><tr> 30<td valign="top"> 31<h2><span class="refentrytitle"><a name="GstAudioAggregator.top_of_page"></a>GstAudioAggregator</span></h2> 32<p>GstAudioAggregator — Base class that manages a set of audio input pads 33with the purpose of aggregating or mixing their raw audio input buffers</p> 34</td> 35<td class="gallery_image" valign="top" align="right"></td> 36</tr></table></div> 37<div class="refsect1"> 38<a name="GstAudioAggregator.functions"></a><h2>Functions</h2> 39<div class="informaltable"><table class="informaltable" width="100%" border="0"> 40<colgroup> 41<col width="150px" class="functions_return"> 42<col class="functions_name"> 43</colgroup> 44<tbody><tr> 45<td class="function_type"> 46<span class="returnvalue">void</span> 47</td> 48<td class="function_name"> 49<a class="link" href="GstAudioAggregator.html#gst-audio-aggregator-set-sink-caps" title="gst_audio_aggregator_set_sink_caps ()">gst_audio_aggregator_set_sink_caps</a> <span class="c_punctuation">()</span> 50</td> 51</tr></tbody> 52</table></div> 53</div> 54<div class="refsect1"> 55<a name="GstAudioAggregator.properties"></a><h2>Properties</h2> 56<div class="informaltable"><table class="informaltable" border="0"> 57<colgroup> 58<col width="150px" class="properties_type"> 59<col width="300px" class="properties_name"> 60<col width="200px" class="properties_flags"> 61</colgroup> 62<tbody> 63<tr> 64<td class="property_type"><a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#guint64"><span class="type">guint64</span></a></td> 65<td class="property_name"><a class="link" href="GstAudioAggregator.html#GstAudioAggregator--alignment-threshold" title="The “alignment-threshold” property">alignment-threshold</a></td> 66<td class="property_flags">Read / Write</td> 67</tr> 68<tr> 69<td class="property_type"><a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#guint64"><span class="type">guint64</span></a></td> 70<td class="property_name"><a class="link" href="GstAudioAggregator.html#GstAudioAggregator--discont-wait" title="The “discont-wait” property">discont-wait</a></td> 71<td class="property_flags">Read / Write</td> 72</tr> 73<tr> 74<td class="property_type"><a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#guint64"><span class="type">guint64</span></a></td> 75<td class="property_name"><a class="link" href="GstAudioAggregator.html#GstAudioAggregator--output-buffer-duration" title="The “output-buffer-duration” property">output-buffer-duration</a></td> 76<td class="property_flags">Read / Write</td> 77</tr> 78<tr> 79<td class="property_type"> 80<a href="/usr/share/gtk-doc/html/gstreamer-1.0/GstStructure.html#GstStructure-struct"><span class="type">GstStructure</span></a> *</td> 81<td class="property_name"><a class="link" href="GstAudioAggregator.html#GstAudioAggregatorConvertPad--converter-config" title="The “converter-config” property">converter-config</a></td> 82<td class="property_flags">Read / Write</td> 83</tr> 84</tbody> 85</table></div> 86</div> 87<a name="GstAudioAggregatorPad"></a><a name="GstAudioAggregatorConvertPad"></a><div class="refsect1"> 88<a name="GstAudioAggregator.other"></a><h2>Types and Values</h2> 89<div class="informaltable"><table class="informaltable" width="100%" border="0"> 90<colgroup> 91<col width="150px" class="name"> 92<col class="description"> 93</colgroup> 94<tbody> 95<tr> 96<td class="datatype_keyword">struct</td> 97<td class="function_name"><a class="link" href="GstAudioAggregator.html#GstAudioAggregator-struct" title="struct GstAudioAggregator">GstAudioAggregator</a></td> 98</tr> 99<tr> 100<td class="datatype_keyword">struct</td> 101<td class="function_name"><a class="link" href="GstAudioAggregator.html#GstAudioAggregatorClass" title="struct GstAudioAggregatorClass">GstAudioAggregatorClass</a></td> 102</tr> 103<tr> 104<td class="datatype_keyword">struct</td> 105<td class="function_name"><a class="link" href="GstAudioAggregator.html#GstAudioAggregatorPad-struct" title="struct GstAudioAggregatorPad">GstAudioAggregatorPad</a></td> 106</tr> 107<tr> 108<td class="datatype_keyword">struct</td> 109<td class="function_name"><a class="link" href="GstAudioAggregator.html#GstAudioAggregatorPadClass" title="struct GstAudioAggregatorPadClass">GstAudioAggregatorPadClass</a></td> 110</tr> 111<tr> 112<td class="datatype_keyword">struct</td> 113<td class="function_name"><a class="link" href="GstAudioAggregator.html#GstAudioAggregatorConvertPad-struct" title="struct GstAudioAggregatorConvertPad">GstAudioAggregatorConvertPad</a></td> 114</tr> 115<tr> 116<td class="datatype_keyword">struct</td> 117<td class="function_name"><a class="link" href="GstAudioAggregator.html#GstAudioAggregatorConvertPadClass" title="struct GstAudioAggregatorConvertPadClass">GstAudioAggregatorConvertPadClass</a></td> 118</tr> 119</tbody> 120</table></div> 121</div> 122<div class="refsect1"> 123<a name="GstAudioAggregator.object-hierarchy"></a><h2>Object Hierarchy</h2> 124<pre class="screen"> <a href="/usr/share/gtk-doc/html/gobject/gobject-The-Base-Object-Type.html#GObject-struct">GObject</a> 125 <span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gobject/gobject-The-Base-Object-Type.html#GInitiallyUnowned">GInitiallyUnowned</a> 126 <span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gstreamer-1.0/GstObject.html#GstObject-struct">GstObject</a> 127 <span class="lineart">├──</span> <a href="/usr/share/gtk-doc/html/gstreamer-1.0/GstElement.html#GstElement-struct">GstElement</a> 128 <span class="lineart">│</span> <span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gstreamer-libs-1.0/GstAggregator.html#GstAggregator-struct">GstAggregator</a> 129 <span class="lineart">│</span> <span class="lineart">╰──</span> GstAudioAggregator 130 <span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gstreamer-1.0/GstPad.html#GstPad-struct">GstPad</a> 131 <span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gstreamer-libs-1.0/GstAggregatorPad.html#GstAggregatorPad-struct">GstAggregatorPad</a> 132 <span class="lineart">╰──</span> GstAudioAggregatorPad 133 <span class="lineart">╰──</span> GstAudioAggregatorConvertPad 134</pre> 135</div> 136<div class="refsect1"> 137<a name="GstAudioAggregator.includes"></a><h2>Includes</h2> 138<pre class="synopsis">#include <gst/audio/audio.h> 139</pre> 140</div> 141<div class="refsect1"> 142<a name="GstAudioAggregator.description"></a><h2>Description</h2> 143<p>Subclasses must use (a subclass of) <a class="link" href="GstAudioAggregator.html#GstAudioAggregatorPad"><span class="type">GstAudioAggregatorPad</span></a> for both 144their source and sink pads, 145<a href="/usr/share/gtk-doc/html/gstreamer-1.0/GstElement.html#gst-element-class-add-static-pad-template-with-gtype"><code class="function">gst_element_class_add_static_pad_template_with_gtype()</code></a> is a convenient 146helper.</p> 147<p><a class="link" href="GstAudioAggregator.html" title="GstAudioAggregator"><span class="type">GstAudioAggregator</span></a> can perform conversion on the data arriving 148on its sink pads, based on the format expected downstream: in order 149to enable that behaviour, the GType of the sink pads must either be 150a (subclass of) <a class="link" href="GstAudioAggregator.html#GstAudioAggregatorConvertPad"><span class="type">GstAudioAggregatorConvertPad</span></a> to use the default 151<a class="link" href="gst-plugins-base-libs-GstAudioConverter.html#GstAudioConverter" title="GstAudioConverter"><span class="type">GstAudioConverter</span></a> implementation, or a subclass of <a class="link" href="GstAudioAggregator.html#GstAudioAggregatorPad"><span class="type">GstAudioAggregatorPad</span></a> 152implementing <a class="link" href="GstAudioAggregator.html#GstAudioAggregatorPadClass.convert-buffer"><span class="type">GstAudioAggregatorPadClass.convert_buffer</span></a>.</p> 153<p>To allow for the output caps to change, the mechanism is the same as 154above, with the GType of the source pad.</p> 155<p>See <a href="/usr/share/gtk-doc/html/gst-plugins-base-plugins-1.0/gst-plugins-base-plugins-audiomixer.html#GstAudioMixer-struct"><span class="type">GstAudioMixer</span></a> for an example.</p> 156<p>When conversion is enabled, <a class="link" href="GstAudioAggregator.html" title="GstAudioAggregator"><span class="type">GstAudioAggregator</span></a> will accept 157any type of raw audio caps and perform conversion 158on the data arriving on its sink pads, with whatever downstream 159expects as the target format.</p> 160<p>In case downstream caps are not fully fixated, it will use 161the first configured sink pad to finish fixating its source pad 162caps.</p> 163<p>A notable exception for now is the sample rate, sink pads must 164have the same sample rate as either the downstream requirement, 165or the first configured pad, or a combination of both (when 166downstream specifies a range or a set of acceptable rates).</p> 167</div> 168<div class="refsect1"> 169<a name="GstAudioAggregator.functions_details"></a><h2>Functions</h2> 170<div class="refsect2"> 171<a name="gst-audio-aggregator-set-sink-caps"></a><h3>gst_audio_aggregator_set_sink_caps ()</h3> 172<pre class="programlisting"><span class="returnvalue">void</span> 173gst_audio_aggregator_set_sink_caps (<em class="parameter"><code><a class="link" href="GstAudioAggregator.html" title="GstAudioAggregator"><span class="type">GstAudioAggregator</span></a> *aagg</code></em>, 174 <em class="parameter"><code><a class="link" href="GstAudioAggregator.html#GstAudioAggregatorPad"><span class="type">GstAudioAggregatorPad</span></a> *pad</code></em>, 175 <em class="parameter"><code><a href="/usr/share/gtk-doc/html/gstreamer-1.0/GstCaps.html#GstCaps-struct"><span class="type">GstCaps</span></a> *caps</code></em>);</pre> 176</div> 177</div> 178<div class="refsect1"> 179<a name="GstAudioAggregator.other_details"></a><h2>Types and Values</h2> 180<div class="refsect2"> 181<a name="GstAudioAggregator-struct"></a><h3>struct GstAudioAggregator</h3> 182<pre class="programlisting">struct GstAudioAggregator { 183 GstCaps *current_caps; 184}; 185</pre> 186<p>GstAudioAggregator object</p> 187<div class="refsect3"> 188<a name="GstAudioAggregator.members"></a><h4>Members</h4> 189<div class="informaltable"><table class="informaltable" width="100%" border="0"> 190<colgroup> 191<col width="300px" class="struct_members_name"> 192<col class="struct_members_description"> 193<col width="200px" class="struct_members_annotations"> 194</colgroup> 195<tbody><tr> 196<td class="struct_member_name"><p><a href="/usr/share/gtk-doc/html/gstreamer-1.0/GstCaps.html#GstCaps-struct"><span class="type">GstCaps</span></a> *<em class="structfield"><code><a name="GstAudioAggregator-struct.current-caps"></a>current_caps</code></em>;</p></td> 197<td class="struct_member_description"><p>The caps set by the subclass</p></td> 198<td class="struct_member_annotations"> </td> 199</tr></tbody> 200</table></div> 201</div> 202<p class="since">Since: <a class="link" href="ix04.html#api-index-1.14">1.14</a></p> 203</div> 204<hr> 205<div class="refsect2"> 206<a name="GstAudioAggregatorClass"></a><h3>struct GstAudioAggregatorClass</h3> 207<pre class="programlisting">struct GstAudioAggregatorClass { 208 GstAggregatorClass parent_class; 209 210 GstBuffer * (* create_output_buffer) (GstAudioAggregator * aagg, 211 guint num_frames); 212 gboolean (* aggregate_one_buffer) (GstAudioAggregator * aagg, 213 GstAudioAggregatorPad * pad, GstBuffer * inbuf, guint in_offset, 214 GstBuffer * outbuf, guint out_offset, guint num_frames); 215}; 216</pre> 217<div class="refsect3"> 218<a name="GstAudioAggregatorClass.members"></a><h4>Members</h4> 219<div class="informaltable"><table class="informaltable" width="100%" border="0"> 220<colgroup> 221<col width="300px" class="struct_members_name"> 222<col class="struct_members_description"> 223<col width="200px" class="struct_members_annotations"> 224</colgroup> 225<tbody> 226<tr> 227<td class="struct_member_name"><p><em class="structfield"><code><a name="GstAudioAggregatorClass.create-output-buffer"></a>create_output_buffer</code></em> ()</p></td> 228<td class="struct_member_description"><p>Create a new output buffer contains num_frames frames.</p></td> 229<td class="struct_member_annotations"> </td> 230</tr> 231<tr> 232<td class="struct_member_name"><p><em class="structfield"><code><a name="GstAudioAggregatorClass.aggregate-one-buffer"></a>aggregate_one_buffer</code></em> ()</p></td> 233<td class="struct_member_description"><p>Aggregates one input buffer to the output 234buffer. The in_offset and out_offset are in "frames", which is 235the size of a sample times the number of channels. Returns TRUE if 236any non-silence was added to the buffer</p></td> 237<td class="struct_member_annotations"> </td> 238</tr> 239</tbody> 240</table></div> 241</div> 242<p class="since">Since: <a class="link" href="ix04.html#api-index-1.14">1.14</a></p> 243</div> 244<hr> 245<div class="refsect2"> 246<a name="GstAudioAggregatorPad-struct"></a><h3>struct GstAudioAggregatorPad</h3> 247<pre class="programlisting">struct GstAudioAggregatorPad { 248 /* read-only, with OBJECT_LOCK */ 249 GstAudioInfo info; 250}; 251</pre> 252<p>The default implementation of GstPad used with <a class="link" href="GstAudioAggregator.html" title="GstAudioAggregator"><span class="type">GstAudioAggregator</span></a></p> 253<div class="refsect3"> 254<a name="GstAudioAggregatorPad.members"></a><h4>Members</h4> 255<div class="informaltable"><table class="informaltable" width="100%" border="0"> 256<colgroup> 257<col width="300px" class="struct_members_name"> 258<col class="struct_members_description"> 259<col width="200px" class="struct_members_annotations"> 260</colgroup> 261<tbody><tr> 262<td class="struct_member_name"><p><a class="link" href="gst-plugins-base-libs-GstAudio.html#GstAudioInfo"><span class="type">GstAudioInfo</span></a> <em class="structfield"><code><a name="GstAudioAggregatorPad-struct.info"></a>info</code></em>;</p></td> 263<td class="struct_member_description"><p>The audio info for this pad set from the incoming caps</p></td> 264<td class="struct_member_annotations"> </td> 265</tr></tbody> 266</table></div> 267</div> 268<p class="since">Since: <a class="link" href="ix04.html#api-index-1.14">1.14</a></p> 269</div> 270<hr> 271<div class="refsect2"> 272<a name="GstAudioAggregatorPadClass"></a><h3>struct GstAudioAggregatorPadClass</h3> 273<pre class="programlisting">struct GstAudioAggregatorPadClass { 274 GstAggregatorPadClass parent_class; 275 276 GstBuffer * (* convert_buffer) (GstAudioAggregatorPad * pad, 277 GstAudioInfo *in_info, 278 GstAudioInfo *out_info, 279 GstBuffer * buffer); 280 281 void (* update_conversion_info) (GstAudioAggregatorPad *pad); 282}; 283</pre> 284<div class="refsect3"> 285<a name="GstAudioAggregatorPadClass.members"></a><h4>Members</h4> 286<div class="informaltable"><table class="informaltable" width="100%" border="0"> 287<colgroup> 288<col width="300px" class="struct_members_name"> 289<col class="struct_members_description"> 290<col width="200px" class="struct_members_annotations"> 291</colgroup> 292<tbody> 293<tr> 294<td class="struct_member_name"><p><em class="structfield"><code><a name="GstAudioAggregatorPadClass.convert-buffer"></a>convert_buffer</code></em> ()</p></td> 295<td class="struct_member_description"><p>Convert a buffer from one format to another.</p></td> 296<td class="struct_member_annotations"> </td> 297</tr> 298<tr> 299<td class="struct_member_name"><p><em class="structfield"><code><a name="GstAudioAggregatorPadClass.update-conversion-info"></a>update_conversion_info</code></em> ()</p></td> 300<td class="struct_member_description"><p>Called when either the input or output 301formats have changed.</p></td> 302<td class="struct_member_annotations"> </td> 303</tr> 304</tbody> 305</table></div> 306</div> 307<p class="since">Since: <a class="link" href="ix04.html#api-index-1.14">1.14</a></p> 308</div> 309<hr> 310<div class="refsect2"> 311<a name="GstAudioAggregatorConvertPad-struct"></a><h3>struct GstAudioAggregatorConvertPad</h3> 312<pre class="programlisting">struct GstAudioAggregatorConvertPad;</pre> 313<p>An implementation of GstPad that can be used with <a class="link" href="GstAudioAggregator.html" title="GstAudioAggregator"><span class="type">GstAudioAggregator</span></a>.</p> 314<p>See <a class="link" href="GstAudioAggregator.html" title="GstAudioAggregator"><span class="type">GstAudioAggregator</span></a> for more details.</p> 315<p class="since">Since: <a class="link" href="ix04.html#api-index-1.14">1.14</a></p> 316</div> 317<hr> 318<div class="refsect2"> 319<a name="GstAudioAggregatorConvertPadClass"></a><h3>struct GstAudioAggregatorConvertPadClass</h3> 320<pre class="programlisting">struct GstAudioAggregatorConvertPadClass { 321 GstAudioAggregatorPadClass parent_class; 322}; 323</pre> 324<p class="since">Since: <a class="link" href="ix04.html#api-index-1.14">1.14</a></p> 325</div> 326</div> 327<div class="refsect1"> 328<a name="GstAudioAggregator.property-details"></a><h2>Property Details</h2> 329<div class="refsect2"> 330<a name="GstAudioAggregator--alignment-threshold"></a><h3>The <code class="literal">“alignment-threshold”</code> property</h3> 331<pre class="programlisting"> “alignment-threshold” <a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#guint64"><span class="type">guint64</span></a></pre> 332<p>Timestamp alignment threshold in nanoseconds.</p> 333<p>Flags: Read / Write</p> 334<p>Allowed values: <= 18446744073709551614</p> 335<p>Default value: 40000000</p> 336</div> 337<hr> 338<div class="refsect2"> 339<a name="GstAudioAggregator--discont-wait"></a><h3>The <code class="literal">“discont-wait”</code> property</h3> 340<pre class="programlisting"> “discont-wait” <a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#guint64"><span class="type">guint64</span></a></pre> 341<p>Window of time in nanoseconds to wait before creating a discontinuity.</p> 342<p>Flags: Read / Write</p> 343<p>Allowed values: <= 18446744073709551614</p> 344<p>Default value: 1000000000</p> 345</div> 346<hr> 347<div class="refsect2"> 348<a name="GstAudioAggregator--output-buffer-duration"></a><h3>The <code class="literal">“output-buffer-duration”</code> property</h3> 349<pre class="programlisting"> “output-buffer-duration” <a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#guint64"><span class="type">guint64</span></a></pre> 350<p>Output block size in nanoseconds.</p> 351<p>Flags: Read / Write</p> 352<p>Allowed values: >= 1</p> 353<p>Default value: 10000000</p> 354</div> 355<hr> 356<div class="refsect2"> 357<a name="GstAudioAggregatorConvertPad--converter-config"></a><h3>The <code class="literal">“converter-config”</code> property</h3> 358<pre class="programlisting"> “converter-config” <a href="/usr/share/gtk-doc/html/gstreamer-1.0/GstStructure.html#GstStructure-struct"><span class="type">GstStructure</span></a> *</pre> 359<p>A GstStructure describing the configuration that should be used when converting this pad's audio buffers.</p> 360<p>Flags: Read / Write</p> 361</div> 362</div> 363<div class="refsect1"> 364<a name="GstAudioAggregator.see-also"></a><h2>See Also</h2> 365<p><a href="/usr/share/gtk-doc/html/gstreamer-libs-1.0/GstAggregator.html#GstAggregator-struct"><span class="type">GstAggregator</span></a>, <a href="/usr/share/gtk-doc/html/gst-plugins-base-plugins-1.0/gst-plugins-base-plugins-audiomixer.html#GstAudioMixer-struct"><span class="type">GstAudioMixer</span></a></p> 366</div> 367</div> 368<div class="footer"> 369<hr>Generated by GTK-Doc V1.28</div> 370</body> 371</html>
