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

   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>gstaudiofilter</title>
   6 <meta name="generator" content="DocBook XSL Stylesheets V1.76.1">
   7 <link rel="home" href="index.html" title="GStreamer Base Plugins 0.10 Library Reference Manual">
   8 <link rel="up" href="gstreamer-audio.html" title="Audio Library">
   9 <link rel="prev" href="gst-plugins-base-libs-gstaudioencoder.html" title="gstaudioencoder">
  10 <link rel="next" href="gst-plugins-base-libs-gstaudiomixerutils.html" title="gstaudiomixerutils">
  11 <meta name="generator" content="GTK-Doc V1.18 (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="2">
  16 <tr valign="middle">
  17 <td><a accesskey="p" href="gst-plugins-base-libs-gstaudioencoder.html"><img src="left.png" width="24" height="24" border="0" alt="Prev"></a></td>
  18 <td><a accesskey="u" href="gstreamer-audio.html"><img src="up.png" width="24" height="24" border="0" alt="Up"></a></td>
  19 <td><a accesskey="h" href="index.html"><img src="home.png" width="24" height="24" border="0" alt="Home"></a></td>
  20 <th width="100%" align="center">GStreamer Base Plugins 0.10 Library Reference Manual</th>
  21 <td><a accesskey="n" href="gst-plugins-base-libs-gstaudiomixerutils.html"><img src="right.png" width="24" height="24" border="0" alt="Next"></a></td>
  22 </tr>
  23 <tr><td colspan="5" class="shortcuts">
  24 <a href="#gst-plugins-base-libs-gstaudiofilter.synopsis" class="shortcut">Top</a>
  25                    |
  26                   <a href="#gst-plugins-base-libs-gstaudiofilter.description" class="shortcut">Description</a>
  27                    |
  28                   <a href="#gst-plugins-base-libs-gstaudiofilter.object-hierarchy" class="shortcut">Object Hierarchy</a>
  29 </td></tr>
  30 </table>
  31 <div class="refentry">
  32 <a name="gst-plugins-base-libs-gstaudiofilter"></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-gstaudiofilter.top_of_page"></a>gstaudiofilter</span></h2>
  36 <p>gstaudiofilter — Base class for simple audio filters</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-gstaudiofilter.synopsis"></a><h2>Synopsis</h2>
  42 <a name="GstAudioFilter"></a><pre class="synopsis">
  43 #include &lt;gst/audio/gstaudiofilter.h&gt;
  44
  45 struct              <a class="link" href="gst-plugins-base-libs-gstaudiofilter.html#GstAudioFilter-struct" title="struct GstAudioFilter">GstAudioFilter</a>;
  46 struct              <a class="link" href="gst-plugins-base-libs-gstaudiofilter.html#GstAudioFilterClass" title="struct GstAudioFilterClass">GstAudioFilterClass</a>;
  47 <span class="returnvalue">void</span>                <a class="link" href="gst-plugins-base-libs-gstaudiofilter.html#gst-audio-filter-class-add-pad-templates" title="gst_audio_filter_class_add_pad_templates ()">gst_audio_filter_class_add_pad_templates</a>
  48                                                         (<em class="parameter"><code><a class="link" href="gst-plugins-base-libs-gstaudiofilter.html#GstAudioFilterClass" title="struct GstAudioFilterClass"><span class="type">GstAudioFilterClass</span></a> *klass</code></em>,
  49                                                          <em class="parameter"><code>const <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstCaps.html#GstCaps"><span class="type">GstCaps</span></a> *allowed_caps</code></em>);
  50 </pre>
  51 </div>
  52 <div class="refsect1">
  53 <a name="gst-plugins-base-libs-gstaudiofilter.object-hierarchy"></a><h2>Object Hierarchy</h2>
  54 <pre class="synopsis">
  55   <a href="http://library.gnome.org/devel/gobject/unstable/gobject-The-Base-Object-Type.html#GObject">GObject</a>
  56    +----<a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstObject.html">GstObject</a>
  57          +----<a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstElement.html">GstElement</a>
  58                +----<a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer-libs/html/GstBaseTransform.html">GstBaseTransform</a>
  59                      +----GstAudioFilter
  60 </pre>
  61 </div>
  62 <div class="refsect1">
  63 <a name="gst-plugins-base-libs-gstaudiofilter.description"></a><h2>Description</h2>
  64 <p>
  65 <a class="link" href="gst-plugins-base-libs-gstaudiofilter.html#GstAudioFilter"><span class="type">GstAudioFilter</span></a> is a <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer-libs/html/GstBaseTransform.html"><span class="type">GstBaseTransform</span></a>-derived base class for simple audio
  66 filters, ie. those that output the same format that they get as input.
  67 </p>
  68 <p>
  69 <a class="link" href="gst-plugins-base-libs-gstaudiofilter.html#GstAudioFilter"><span class="type">GstAudioFilter</span></a> will parse the input format for you (with error checking)
  70 before calling your setup function. Also, elements deriving from
  71 <a class="link" href="gst-plugins-base-libs-gstaudiofilter.html#GstAudioFilter"><span class="type">GstAudioFilter</span></a> may use <a class="link" href="gst-plugins-base-libs-gstaudiofilter.html#gst-audio-filter-class-add-pad-templates" title="gst_audio_filter_class_add_pad_templates ()"><code class="function">gst_audio_filter_class_add_pad_templates()</code></a> from
  72 their base_init function to easily configure the set of caps/formats that
  73 the element is able to handle.
  74 </p>
  75 <p>
  76 Derived classes should override the <a class="link" href="gst-plugins-base-libs-gstaudiofilter.html#GstAudioFilterClass.setup"><code class="function">GstAudioFilterClass.setup()</code></a> and
  77 <code class="function">GstBaseTransformClass.transform_ip()</code> and/or
  78 <code class="function">GstBaseTransformClass.transform()</code>
  79 virtual functions in their class_init function.
  80 </p>
  81 <p>
  82 Last reviewed on 2007-02-03 (0.10.11.1)
  83 </p>
  84 </div>
  85 <div class="refsect1">
  86 <a name="gst-plugins-base-libs-gstaudiofilter.details"></a><h2>Details</h2>
  87 <div class="refsect2">
  88 <a name="GstAudioFilter-struct"></a><h3>struct GstAudioFilter</h3>
  89 <pre class="programlisting">struct GstAudioFilter;</pre>
  90 <p>
  91 Base class for audio filters with the same format for input and output.
  92 </p>
  93 <p class="since">Since 0.10.12</p>
  94 </div>
  95 <hr>
  96 <div class="refsect2">
  97 <a name="GstAudioFilterClass"></a><h3>struct GstAudioFilterClass</h3>
  98 <pre class="programlisting">struct GstAudioFilterClass {
  99   GstBaseTransformClass basetransformclass;
 100
 101   /* virtual function, called whenever the format changes */
 102   gboolean  (*setup) (GstAudioFilter * filter, GstRingBufferSpec * format);
 103 };
 104 </pre>
 105 <p>
 106 In addition to the <em class="parameter"><code>setup</code></em> virtual function, you should also override the
 107 GstBaseTransform::transform and/or GstBaseTransform::transform_ip virtual
 108 function.
 109 </p>
 110 <div class="variablelist"><table border="0">
 111 <col align="left" valign="top">
 112 <tbody>
 113 <tr>
 114 <td><p><span class="term"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer-libs/html/GstBaseTransform.html#GstBaseTransformClass"><span class="type">GstBaseTransformClass</span></a> <em class="structfield"><code><a name="GstAudioFilterClass.basetransformclass"></a>basetransformclass</code></em>;</span></p></td>
 115 <td>parent class</td>
 116 </tr>
 117 <tr>
 118 <td><p><span class="term"><em class="structfield"><code><a name="GstAudioFilterClass.setup"></a>setup</code></em> ()</span></p></td>
 119 <td>virtual function called whenever the format changes</td>
 120 </tr>
 121 </tbody>
 122 </table></div>
 123 <p class="since">Since 0.10.12</p>
 124 </div>
 125 <hr>
 126 <div class="refsect2">
 127 <a name="gst-audio-filter-class-add-pad-templates"></a><h3>gst_audio_filter_class_add_pad_templates ()</h3>
 128 <pre class="programlisting"><span class="returnvalue">void</span>                gst_audio_filter_class_add_pad_templates
 129                                                         (<em class="parameter"><code><a class="link" href="gst-plugins-base-libs-gstaudiofilter.html#GstAudioFilterClass" title="struct GstAudioFilterClass"><span class="type">GstAudioFilterClass</span></a> *klass</code></em>,
 130                                                          <em class="parameter"><code>const <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstCaps.html#GstCaps"><span class="type">GstCaps</span></a> *allowed_caps</code></em>);</pre>
 131 <p>
 132 Convenience function to add pad templates to this element class, with
 133 <em class="parameter"><code>allowed_caps</code></em> as the caps that can be handled.
 134 </p>
 135 <p>
 136 This function is usually used from within a GObject base_init function.
 137 </p>
 138 <div class="variablelist"><table border="0">
 139 <col align="left" valign="top">
 140 <tbody>
 141 <tr>
 142 <td><p><span class="term"><em class="parameter"><code>klass</code></em> :</span></p></td>
 143 <td>an <a class="link" href="gst-plugins-base-libs-gstaudiofilter.html#GstAudioFilterClass" title="struct GstAudioFilterClass"><span class="type">GstAudioFilterClass</span></a>
 144 </td>
 145 </tr>
 146 <tr>
 147 <td><p><span class="term"><em class="parameter"><code>allowed_caps</code></em> :</span></p></td>
 148 <td>what formats the filter can handle, as <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstCaps.html#GstCaps"><span class="type">GstCaps</span></a>
 149 </td>
 150 </tr>
 151 </tbody>
 152 </table></div>
 153 <p class="since">Since 0.10.12</p>
 154 </div>
 155 </div>
 156 </div>
 157 <div class="footer">
 158 <hr>
 159           Generated by GTK-Doc V1.18</div>
 160 </body>
 161 </html>