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>volume: GStreamer Base Plugins 1.0 Plugins 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 Plugins Reference Manual"> 8<link rel="up" href="ch01.html" title="gst-plugins-base Elements"> 9<link rel="prev" href="gst-plugins-base-plugins-videotestsrc.html" title="videotestsrc"> 10<link rel="next" href="gst-plugins-base-plugins-vorbisdec.html" title="vorbisdec"> 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="#gst-plugins-base-plugins-volume.description" class="shortcut">Description</a></span><span id="nav_hierarchy"> <span class="dim">|</span> 19 <a href="#gst-plugins-base-plugins-volume.object-hierarchy" class="shortcut">Object Hierarchy</a></span><span id="nav_interfaces"> <span class="dim">|</span> 20 <a href="#gst-plugins-base-plugins-volume.implemented-interfaces" class="shortcut">Implemented Interfaces</a></span><span id="nav_properties"> <span class="dim">|</span> 21 <a href="#gst-plugins-base-plugins-volume.properties" class="shortcut">Properties</a></span> 22</td> 23<td><a accesskey="h" href="index.html"><img src="home.png" width="16" height="16" border="0" alt="Home"></a></td> 24<td><a accesskey="u" href="ch01.html"><img src="up.png" width="16" height="16" border="0" alt="Up"></a></td> 25<td><a accesskey="p" href="gst-plugins-base-plugins-videotestsrc.html"><img src="left.png" width="16" height="16" border="0" alt="Prev"></a></td> 26<td><a accesskey="n" href="gst-plugins-base-plugins-vorbisdec.html"><img src="right.png" width="16" height="16" border="0" alt="Next"></a></td> 27</tr></table> 28<div class="refentry"> 29<a name="gst-plugins-base-plugins-volume"></a><div class="titlepage"></div> 30<div class="refnamediv"><table width="100%"><tr> 31<td valign="top"> 32<h2><span class="refentrytitle"><a name="gst-plugins-base-plugins-volume.top_of_page"></a>volume</span></h2> 33<p>volume</p> 34</td> 35<td class="gallery_image" valign="top" align="right"></td> 36</tr></table></div> 37<div class="refsect1"> 38<a name="gst-plugins-base-plugins-volume.properties"></a><h2>Properties</h2> 39<div class="informaltable"><table class="informaltable" border="0"> 40<colgroup> 41<col width="150px" class="properties_type"> 42<col width="300px" class="properties_name"> 43<col width="200px" class="properties_flags"> 44</colgroup> 45<tbody> 46<tr> 47<td class="property_type"><a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></td> 48<td class="property_name"><a class="link" href="gst-plugins-base-plugins-volume.html#GstVolume--mute" title="The “mute” property">mute</a></td> 49<td class="property_flags">Read / Write</td> 50</tr> 51<tr> 52<td class="property_type"><a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gdouble"><span class="type">gdouble</span></a></td> 53<td class="property_name"><a class="link" href="gst-plugins-base-plugins-volume.html#GstVolume--volume" title="The “volume” property">volume</a></td> 54<td class="property_flags">Read / Write</td> 55</tr> 56</tbody> 57</table></div> 58</div> 59<a name="GstVolume"></a><div class="refsect1"> 60<a name="gst-plugins-base-plugins-volume.other"></a><h2>Types and Values</h2> 61<div class="informaltable"><table class="informaltable" width="100%" border="0"> 62<colgroup> 63<col width="150px" class="name"> 64<col class="description"> 65</colgroup> 66<tbody><tr> 67<td class="datatype_keyword">struct</td> 68<td class="function_name"><a class="link" href="gst-plugins-base-plugins-volume.html#GstVolume-struct" title="struct GstVolume">GstVolume</a></td> 69</tr></tbody> 70</table></div> 71</div> 72<div class="refsect1"> 73<a name="gst-plugins-base-plugins-volume.object-hierarchy"></a><h2>Object Hierarchy</h2> 74<pre class="screen"> <a href="/usr/share/gtk-doc/html/gobject/gobject-The-Base-Object-Type.html#GObject-struct">GObject</a> 75 <span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gobject/gobject-The-Base-Object-Type.html#GInitiallyUnowned">GInitiallyUnowned</a> 76 <span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gstreamer-1.0/GstObject.html#GstObject-struct">GstObject</a> 77 <span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gstreamer-1.0/GstElement.html#GstElement-struct">GstElement</a> 78 <span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gstreamer-libs-1.0/GstBaseTransform.html#GstBaseTransform-struct">GstBaseTransform</a> 79 <span class="lineart">╰──</span> <a href="../html/GstAudioFilter.html#GstAudioFilter-struct">GstAudioFilter</a> 80 <span class="lineart">╰──</span> GstVolume 81</pre> 82</div> 83<div class="refsect1"> 84<a name="gst-plugins-base-plugins-volume.implemented-interfaces"></a><h2>Implemented Interfaces</h2> 85<p> 86GstVolume implements 87 <a href="../html/GstStreamVolume.html#GstStreamVolume-struct">GstStreamVolume</a>.</p> 88</div> 89<div class="refsect1"> 90<a name="gst-plugins-base-plugins-volume.description"></a><h2>Description</h2> 91<p>The volume element changes the volume of the audio data.</p> 92<div class="refsect3"> 93<a name="id-1.2.111.8.3"></a><h4>Example launch line</h4> 94<div class="informalexample"> 95 <table class="listing_frame" border="0" cellpadding="0" cellspacing="0"> 96 <tbody> 97 <tr> 98 <td class="listing_lines" align="right"><pre>1</pre></td> 99 <td class="listing_code"><pre class="programlisting">gst<span class="gtkdoc opt">-</span>launch<span class="gtkdoc opt">-</span><span class="number">1.0</span> <span class="gtkdoc opt">-</span>v <span class="gtkdoc opt">-</span>m audiotestsrc <span class="gtkdoc opt">!</span> volume volume<span class="gtkdoc opt">=</span><span class="number">0.5</span> <span class="gtkdoc opt">!</span> level <span class="gtkdoc opt">!</span> fakesink silent<span class="gtkdoc opt">=</span>TRUE</pre></td> 100 </tr> 101 </tbody> 102 </table> 103</div> 104 105<p> 106 This pipeline shows that the level of audiotestsrc has been halved 107(peak values are around -6 dB and RMS around -9 dB) compared to 108the same pipeline without the volume element.</p> 109</div> 110<div class="refsynopsisdiv"> 111<h2>Synopsis</h2> 112<div class="refsect2"> 113<a name="id-1.2.111.8.4.1"></a><h3>Element Information</h3> 114<div class="variablelist"><table border="0" class="variablelist"> 115<colgroup> 116<col align="left" valign="top"> 117<col> 118</colgroup> 119<tbody> 120<tr> 121<td><p><span class="term">plugin</span></p></td> 122<td> 123 <a class="link" href="gst-plugins-base-plugins-plugin-volume.html#plugin-volume">volume</a> 124 </td> 125</tr> 126<tr> 127<td><p><span class="term">author</span></p></td> 128<td>Andy Wingo <wingo@pobox.com></td> 129</tr> 130<tr> 131<td><p><span class="term">class</span></p></td> 132<td>Filter/Effect/Audio</td> 133</tr> 134</tbody> 135</table></div> 136</div> 137<hr> 138<div class="refsect2"> 139<a name="id-1.2.111.8.4.2"></a><h3>Element Pads</h3> 140<div class="variablelist"><table border="0" class="variablelist"> 141<colgroup> 142<col align="left" valign="top"> 143<col> 144</colgroup> 145<tbody> 146<tr> 147<td><p><span class="term">name</span></p></td> 148<td>sink</td> 149</tr> 150<tr> 151<td><p><span class="term">direction</span></p></td> 152<td>sink</td> 153</tr> 154<tr> 155<td><p><span class="term">presence</span></p></td> 156<td>always</td> 157</tr> 158<tr> 159<td><p><span class="term">details</span></p></td> 160<td>audio/x-raw, format=(string){ F32LE, F64LE, S8, S16LE, S24LE, S32LE }, rate=(int)[ 1, 2147483647 ], channels=(int)[ 1, 2147483647 ], layout=(string)interleaved</td> 161</tr> 162</tbody> 163</table></div> 164<div class="variablelist"><table border="0" class="variablelist"> 165<colgroup> 166<col align="left" valign="top"> 167<col> 168</colgroup> 169<tbody> 170<tr> 171<td><p><span class="term">name</span></p></td> 172<td>src</td> 173</tr> 174<tr> 175<td><p><span class="term">direction</span></p></td> 176<td>source</td> 177</tr> 178<tr> 179<td><p><span class="term">presence</span></p></td> 180<td>always</td> 181</tr> 182<tr> 183<td><p><span class="term">details</span></p></td> 184<td>audio/x-raw, format=(string){ F32LE, F64LE, S8, S16LE, S24LE, S32LE }, rate=(int)[ 1, 2147483647 ], channels=(int)[ 1, 2147483647 ], layout=(string)interleaved</td> 185</tr> 186</tbody> 187</table></div> 188</div> 189</div> 190</div> 191<div class="refsect1"> 192<a name="gst-plugins-base-plugins-volume.functions_details"></a><h2>Functions</h2> 193<p></p> 194</div> 195<div class="refsect1"> 196<a name="gst-plugins-base-plugins-volume.other_details"></a><h2>Types and Values</h2> 197<div class="refsect2"> 198<a name="GstVolume-struct"></a><h3>struct GstVolume</h3> 199<pre class="programlisting">struct GstVolume;</pre> 200<p>Opaque data structure.</p> 201</div> 202</div> 203<div class="refsect1"> 204<a name="gst-plugins-base-plugins-volume.property-details"></a><h2>Property Details</h2> 205<div class="refsect2"> 206<a name="GstVolume--mute"></a><h3>The <code class="literal">“mute”</code> property</h3> 207<pre class="programlisting"> “mute” <a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></pre> 208<p>mute channel.</p> 209<p>Flags: Read / Write</p> 210<p>Default value: FALSE</p> 211</div> 212<hr> 213<div class="refsect2"> 214<a name="GstVolume--volume"></a><h3>The <code class="literal">“volume”</code> property</h3> 215<pre class="programlisting"> “volume” <a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gdouble"><span class="type">gdouble</span></a></pre> 216<p>volume factor, 1.0=100%.</p> 217<p>Flags: Read / Write</p> 218<p>Allowed values: [0,10]</p> 219<p>Default value: 1</p> 220</div> 221</div> 222</div> 223<div class="footer"> 224<hr>Generated by GTK-Doc V1.28</div> 225</body> 226</html>
