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<a href="#GstTypeFindFactory.synopsis" class="shortcut">Top</a>
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<a href="#GstTypeFindFactory.description" class="shortcut">Description</a>
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<a href="#GstTypeFindFactory.object-hierarchy" class="shortcut">Object Hierarchy</a>
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<h2><span class="refentrytitle"><a name="GstTypeFindFactory.top_of_page"></a>GstTypeFindFactory</span></h2>
<p>GstTypeFindFactory — Information about registered typefind functions</p>
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<div class="refsynopsisdiv">
<a name="GstTypeFindFactory.synopsis"></a><h2>Synopsis</h2>
<pre class="synopsis">
#include &lt;gst/gst.h&gt;
struct <a class="link" href="GstTypeFindFactory.html#GstTypeFindFactory-struct" title="struct GstTypeFindFactory">GstTypeFindFactory</a>;
<a href="http://library.gnome.org/devel/glib/unstable/glib-Doubly-Linked-Lists.html#GList"><span class="returnvalue">GList</span></a> * <a class="link" href="GstTypeFindFactory.html#gst-type-find-factory-get-list" title="gst_type_find_factory_get_list ()">gst_type_find_factory_get_list</a> (<em class="parameter"><code><span class="type">void</span></code></em>);
<a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gchar"><span class="returnvalue">gchar</span></a> ** <a class="link" href="GstTypeFindFactory.html#gst-type-find-factory-get-extensions" title="gst_type_find_factory_get_extensions ()">gst_type_find_factory_get_extensions</a>
(<em class="parameter"><code><a class="link" href="GstTypeFindFactory.html" title="GstTypeFindFactory"><span class="type">GstTypeFindFactory</span></a> *factory</code></em>);
<a class="link" href="gstreamer-GstCaps.html#GstCaps" title="struct GstCaps"><span class="returnvalue">GstCaps</span></a> * <a class="link" href="GstTypeFindFactory.html#gst-type-find-factory-get-caps" title="gst_type_find_factory_get_caps ()">gst_type_find_factory_get_caps</a> (<em class="parameter"><code><a class="link" href="GstTypeFindFactory.html" title="GstTypeFindFactory"><span class="type">GstTypeFindFactory</span></a> *factory</code></em>);
<span class="returnvalue">void</span> <a class="link" href="GstTypeFindFactory.html#gst-type-find-factory-call-function" title="gst_type_find_factory_call_function ()">gst_type_find_factory_call_function</a> (<em class="parameter"><code><a class="link" href="GstTypeFindFactory.html" title="GstTypeFindFactory"><span class="type">GstTypeFindFactory</span></a> *factory</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstTypeFind.html#GstTypeFind" title="struct GstTypeFind"><span class="type">GstTypeFind</span></a> *find</code></em>);
</pre>
</div>
<div class="refsect1">
<a name="GstTypeFindFactory.object-hierarchy"></a><h2>Object Hierarchy</h2>
<pre class="synopsis">
<a href="http://library.gnome.org/devel/gobject/unstable/gobject-The-Base-Object-Type.html#GObject">GObject</a>
+----<a href="http://library.gnome.org/devel/gobject/unstable/gobject-The-Base-Object-Type.html#GInitiallyUnowned">GInitiallyUnowned</a>
+----<a class="link" href="GstObject.html" title="GstObject">GstObject</a>
+----<a class="link" href="GstPluginFeature.html" title="GstPluginFeature">GstPluginFeature</a>
+----GstTypeFindFactory
</pre>
</div>
<div class="refsect1">
<a name="GstTypeFindFactory.description"></a><h2>Description</h2>
<p>
These functions allow querying informations about registered typefind
functions. How to create and register these functions is described in
the section <GTKDOCLINK HREF="gstreamer-Writing-typefind-functions">
"Writing typefind functions"</GTKDOCLINK>.
</p>
<p>
</p>
<div class="example">
<a name="id494967"></a><p class="title"><b>Example 14. how to write a simple typefinder</b></p>
<div class="example-contents"><pre class="programlisting">
typedef struct {
guint8 *data;
guint size;
guint probability;
GstCaps *data;
} MyTypeFind;
static void
my_peek (gpointer data, gint64 offset, guint size)
{
MyTypeFind *find = (MyTypeFind *) data;
if (offset &gt;= 0 &amp;&amp; offset + size &lt;= find-&gt;size) {
return find-&gt;data + offset;
}
return NULL;
}
static void
my_suggest (gpointer data, guint probability, GstCaps *caps)
{
MyTypeFind *find = (MyTypeFind *) data;
if (probability &gt; find-&gt;probability) {
find-&gt;probability = probability;
gst_caps_replace (&amp;find-&gt;caps, caps);
}
}
static GstCaps *
find_type (guint8 *data, guint size)
{
GList *walk, *type_list;
MyTypeFind find = {data, size, 0, NULL};
GstTypeFind gst_find = {my_peek, my_suggest, &amp;find, };
walk = type_list = gst_type_find_factory_get_list ();
while (walk) {
GstTypeFindFactory *factory = GST_TYPE_FIND_FACTORY (walk-&gt;data);
walk = g_list_next (walk)
gst_type_find_factory_call_function (factory, &amp;gst_find);
}
g_list_free (type_list);
return find.caps;
};
</pre></div>
</div>
<p><br class="example-break">
</p>
<p>
The above example shows how to write a very simple typefinder that
identifies the given data. You can get quite a bit more complicated than
that though.
</p>
<p>
Last reviewed on 2005-11-09 (0.9.4)
</p>
</div>
<div class="refsect1">
<a name="GstTypeFindFactory.details"></a><h2>Details</h2>
<div class="refsect2">
<a name="GstTypeFindFactory-struct"></a><h3>struct GstTypeFindFactory</h3>
<pre class="programlisting">struct GstTypeFindFactory;</pre>
<p>
Object that stores information about a typefind function.
</p>
</div>
<hr>
<div class="refsect2">
<a name="gst-type-find-factory-get-list"></a><h3>gst_type_find_factory_get_list ()</h3>
<pre class="programlisting"><a href="http://library.gnome.org/devel/glib/unstable/glib-Doubly-Linked-Lists.html#GList"><span class="returnvalue">GList</span></a> * gst_type_find_factory_get_list (<em class="parameter"><code><span class="type">void</span></code></em>);</pre>
<p>
Gets the list of all registered typefind factories. You must free the
list using <a class="link" href="GstPluginFeature.html#gst-plugin-feature-list-free" title="gst_plugin_feature_list_free ()"><code class="function">gst_plugin_feature_list_free()</code></a>.
</p>
<p>
The returned factories are sorted by highest rank first, and then by
factory name. (behaviour change since 0.10.26)
</p>
<p>
Free-function: gst_plugin_feature_list_free
</p>
<div class="variablelist"><table border="0">
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<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>the list of all
registered <a class="link" href="GstTypeFindFactory.html" title="GstTypeFindFactory"><span class="type">GstTypeFindFactory</span></a>. <span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>][<acronym title="Generics and defining elements of containers and arrays."><span class="acronym">element-type</span></acronym> Gst.TypeFindFactory]</span>
</td>
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<hr>
<div class="refsect2">
<a name="gst-type-find-factory-get-extensions"></a><h3>gst_type_find_factory_get_extensions ()</h3>
<pre class="programlisting"><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gchar"><span class="returnvalue">gchar</span></a> ** gst_type_find_factory_get_extensions
(<em class="parameter"><code><a class="link" href="GstTypeFindFactory.html" title="GstTypeFindFactory"><span class="type">GstTypeFindFactory</span></a> *factory</code></em>);</pre>
<p>
Gets the extensions associated with a <a class="link" href="GstTypeFindFactory.html" title="GstTypeFindFactory"><span class="type">GstTypeFindFactory</span></a>. The returned
array should not be changed. If you need to change stuff in it, you should
copy it using <a href="http://library.gnome.org/devel/glib/unstable/glib-String-Utility-Functions.html#g-strdupv"><code class="function">g_strdupv()</code></a>. This function may return NULL to indicate
a 0-length list.
</p>
<div class="variablelist"><table border="0">
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<td><p><span class="term"><em class="parameter"><code>factory</code></em> :</span></p></td>
<td>A <a class="link" href="GstTypeFindFactory.html" title="GstTypeFindFactory"><span class="type">GstTypeFindFactory</span></a>
</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>a
NULL-terminated array of extensions associated with this factory. <span class="annotation">[<acronym title="Don't free data after the code is done."><span class="acronym">transfer none</span></acronym>][<acronym title="Parameter points to an array of items."><span class="acronym">array</span></acronym> zero-terminated=1][<acronym title="Generics and defining elements of containers and arrays."><span class="acronym">element-type</span></acronym> utf8]</span>
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<hr>
<div class="refsect2">
<a name="gst-type-find-factory-get-caps"></a><h3>gst_type_find_factory_get_caps ()</h3>
<pre class="programlisting"><a class="link" href="gstreamer-GstCaps.html#GstCaps" title="struct GstCaps"><span class="returnvalue">GstCaps</span></a> * gst_type_find_factory_get_caps (<em class="parameter"><code><a class="link" href="GstTypeFindFactory.html" title="GstTypeFindFactory"><span class="type">GstTypeFindFactory</span></a> *factory</code></em>);</pre>
<p>
Gets the <a class="link" href="gstreamer-GstCaps.html#GstCaps" title="struct GstCaps"><span class="type">GstCaps</span></a> associated with a typefind factory.
</p>
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<td><p><span class="term"><em class="parameter"><code>factory</code></em> :</span></p></td>
<td>A <a class="link" href="GstTypeFindFactory.html" title="GstTypeFindFactory"><span class="type">GstTypeFindFactory</span></a>
</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>the <a class="link" href="gstreamer-GstCaps.html#GstCaps" title="struct GstCaps"><span class="type">GstCaps</span></a> associated with this factory. <span class="annotation">[<acronym title="Don't free data after the code is done."><span class="acronym">transfer none</span></acronym>]</span>
</td>
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<hr>
<div class="refsect2">
<a name="gst-type-find-factory-call-function"></a><h3>gst_type_find_factory_call_function ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gst_type_find_factory_call_function (<em class="parameter"><code><a class="link" href="GstTypeFindFactory.html" title="GstTypeFindFactory"><span class="type">GstTypeFindFactory</span></a> *factory</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstTypeFind.html#GstTypeFind" title="struct GstTypeFind"><span class="type">GstTypeFind</span></a> *find</code></em>);</pre>
<p>
Calls the <a class="link" href="gstreamer-GstTypeFind.html#GstTypeFindFunction" title="GstTypeFindFunction ()"><span class="type">GstTypeFindFunction</span></a> associated with this factory.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>factory</code></em> :</span></p></td>
<td>A <a class="link" href="GstTypeFindFactory.html" title="GstTypeFindFactory"><span class="type">GstTypeFindFactory</span></a>
</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>find</code></em> :</span></p></td>
<td>a properly setup <a class="link" href="gstreamer-GstTypeFind.html#GstTypeFind" title="struct GstTypeFind"><span class="type">GstTypeFind</span></a> entry. The get_data
and suggest_type members must be set. <span class="annotation">[<acronym title="Don't free data after the code is done."><span class="acronym">transfer none</span></acronym>]</span>
</td>
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