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| <a href="#gstreamer-GstContext.synopsis" class="shortcut">Top</a> |
| | |
| <a href="#gstreamer-GstContext.description" class="shortcut">Description</a> |
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| <div class="refentry"> |
| <a name="gstreamer-GstContext"></a><div class="titlepage"></div> |
| <div class="refnamediv"><table width="100%"><tr> |
| <td valign="top"> |
| <h2><span class="refentrytitle"><a name="gstreamer-GstContext.top_of_page"></a>GstContext</span></h2> |
| <p>GstContext — Lightweight objects to represent element contexts</p> |
| </td> |
| <td valign="top" align="right"></td> |
| </tr></table></div> |
| <div class="refsynopsisdiv"> |
| <a name="gstreamer-GstContext.synopsis"></a><h2>Synopsis</h2> |
| <pre class="synopsis"> |
| #include <gst/gst.h> |
| |
| <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext">GstContext</a>; |
| <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="returnvalue">GstContext</span></a> * <a class="link" href="gstreamer-GstContext.html#gst-context-new" title="gst_context_new ()">gst_context_new</a> (<em class="parameter"><code>const <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *context_type</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> persistent</code></em>); |
| <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="returnvalue">GstContext</span></a> * <a class="link" href="gstreamer-GstContext.html#gst-context-ref" title="gst_context_ref ()">gst_context_ref</a> (<em class="parameter"><code><a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> *context</code></em>); |
| <span class="returnvalue">void</span> <a class="link" href="gstreamer-GstContext.html#gst-context-unref" title="gst_context_unref ()">gst_context_unref</a> (<em class="parameter"><code><a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> *context</code></em>); |
| <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="returnvalue">GstContext</span></a> * <a class="link" href="gstreamer-GstContext.html#gst-context-copy" title="gst_context_copy ()">gst_context_copy</a> (<em class="parameter"><code>const <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> *context</code></em>); |
| const <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gchar"><span class="returnvalue">gchar</span></a> * <a class="link" href="gstreamer-GstContext.html#gst-context-get-context-type" title="gst_context_get_context_type ()">gst_context_get_context_type</a> (<em class="parameter"><code>const <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> *context</code></em>); |
| <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a> <a class="link" href="gstreamer-GstContext.html#gst-context-has-context-type" title="gst_context_has_context_type ()">gst_context_has_context_type</a> (<em class="parameter"><code>const <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> *context</code></em>, |
| <em class="parameter"><code>const <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *context_type</code></em>); |
| <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a> <a class="link" href="gstreamer-GstContext.html#gst-context-is-persistent" title="gst_context_is_persistent ()">gst_context_is_persistent</a> (<em class="parameter"><code>const <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> *context</code></em>); |
| const <a class="link" href="gstreamer-GstStructure.html#GstStructure" title="struct GstStructure"><span class="returnvalue">GstStructure</span></a> * <a class="link" href="gstreamer-GstContext.html#gst-context-get-structure" title="gst_context_get_structure ()">gst_context_get_structure</a> (<em class="parameter"><code>const <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> *context</code></em>); |
| <a class="link" href="gstreamer-GstStructure.html#GstStructure" title="struct GstStructure"><span class="returnvalue">GstStructure</span></a> * <a class="link" href="gstreamer-GstContext.html#gst-context-writable-structure" title="gst_context_writable_structure ()">gst_context_writable_structure</a> (<em class="parameter"><code><a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> *context</code></em>); |
| #define <a class="link" href="gstreamer-GstContext.html#gst-context-make-writable" title="gst_context_make_writable()">gst_context_make_writable</a> (context) |
| #define <a class="link" href="gstreamer-GstContext.html#gst-context-is-writable" title="gst_context_is_writable()">gst_context_is_writable</a> (context) |
| <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a> <a class="link" href="gstreamer-GstContext.html#gst-context-replace" title="gst_context_replace ()">gst_context_replace</a> (<em class="parameter"><code><a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> **old_context</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> *new_context</code></em>); |
| </pre> |
| </div> |
| <div class="refsect1"> |
| <a name="gstreamer-GstContext.description"></a><h2>Description</h2> |
| <p> |
| <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> is a container object used to store contexts like a device |
| context, a display server connection and similar concepts that should |
| be shared between multiple elements. |
| </p> |
| <p> |
| Applications can set a context on a complete pipeline by using |
| <a class="link" href="GstElement.html#gst-element-set-context" title="gst_element_set_context ()"><code class="function">gst_element_set_context()</code></a>, which will then be propagated to all |
| child elements. Elements can handle these in GstElement::<code class="function">set_context()</code> |
| and merge them with the context information they already have. |
| </p> |
| <p> |
| When an element needs a context it will do the following actions in this |
| order until one step succeeds: |
| 1) Check if the element already has a context |
| 2) Query downstream with GST_QUERY_CONTEXT for the context |
| 2) Query upstream with GST_QUERY_CONTEXT for the context |
| 3) Post a GST_MESSAGE_NEED_CONTEXT message on the bus with the required |
| context types and afterwards check if a usable context was set now |
| 4) Create a context by itself and post a GST_MESSAGE_HAVE_CONTEXT message |
| on the bus. |
| </p> |
| <p> |
| Bins will catch GST_MESSAGE_NEED_CONTEXT messages and will set any previously |
| known context on the element that asks for it if possible. Otherwise the |
| application should provide one if it can. |
| </p> |
| </div> |
| <div class="refsect1"> |
| <a name="gstreamer-GstContext.details"></a><h2>Details</h2> |
| <div class="refsect2"> |
| <a name="GstContext"></a><h3>GstContext</h3> |
| <pre class="programlisting">typedef struct _GstContext GstContext;</pre> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-context-new"></a><h3>gst_context_new ()</h3> |
| <pre class="programlisting"><a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="returnvalue">GstContext</span></a> * gst_context_new (<em class="parameter"><code>const <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *context_type</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> persistent</code></em>);</pre> |
| <p> |
| Create a new context. |
| </p> |
| <div class="variablelist"><table border="0" class="variablelist"> |
| <colgroup> |
| <col align="left" valign="top"> |
| <col> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>persistent</code></em> :</span></p></td> |
| <td>Persistent context</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>The new context. <span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span> |
| </td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 1.2</p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-context-ref"></a><h3>gst_context_ref ()</h3> |
| <pre class="programlisting"><a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="returnvalue">GstContext</span></a> * gst_context_ref (<em class="parameter"><code><a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> *context</code></em>);</pre> |
| <p> |
| Convenience macro to increase the reference count of the context. |
| </p> |
| <div class="variablelist"><table border="0" class="variablelist"> |
| <colgroup> |
| <col align="left" valign="top"> |
| <col> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>context</code></em> :</span></p></td> |
| <td>the context to ref</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td> |
| <em class="parameter"><code>context</code></em> (for convenience when doing assignments)</td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-context-unref"></a><h3>gst_context_unref ()</h3> |
| <pre class="programlisting"><span class="returnvalue">void</span> gst_context_unref (<em class="parameter"><code><a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> *context</code></em>);</pre> |
| <p> |
| Convenience macro to decrease the reference count of the context, possibly |
| freeing it. |
| </p> |
| <div class="variablelist"><table border="0" class="variablelist"> |
| <colgroup> |
| <col align="left" valign="top"> |
| <col> |
| </colgroup> |
| <tbody><tr> |
| <td><p><span class="term"><em class="parameter"><code>context</code></em> :</span></p></td> |
| <td>the context to unref</td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-context-copy"></a><h3>gst_context_copy ()</h3> |
| <pre class="programlisting"><a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="returnvalue">GstContext</span></a> * gst_context_copy (<em class="parameter"><code>const <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> *context</code></em>);</pre> |
| <p> |
| Creates a copy of the context. Returns a copy of the context. |
| </p> |
| <div class="variablelist"><table border="0" class="variablelist"> |
| <colgroup> |
| <col align="left" valign="top"> |
| <col> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>context</code></em> :</span></p></td> |
| <td>the context to copy</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>a new copy of <em class="parameter"><code>context</code></em>. |
| MT safe. <span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span> |
| </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-context-get-context-type"></a><h3>gst_context_get_context_type ()</h3> |
| <pre class="programlisting">const <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gchar"><span class="returnvalue">gchar</span></a> * gst_context_get_context_type (<em class="parameter"><code>const <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> *context</code></em>);</pre> |
| <p> |
| Get the type of <em class="parameter"><code>context</code></em>. |
| </p> |
| <div class="variablelist"><table border="0" class="variablelist"> |
| <colgroup> |
| <col align="left" valign="top"> |
| <col> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>context</code></em> :</span></p></td> |
| <td>The <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a>.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>The type of the context.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 1.2</p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-context-has-context-type"></a><h3>gst_context_has_context_type ()</h3> |
| <pre class="programlisting"><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a> gst_context_has_context_type (<em class="parameter"><code>const <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> *context</code></em>, |
| <em class="parameter"><code>const <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *context_type</code></em>);</pre> |
| <p> |
| Checks if <em class="parameter"><code>context</code></em> has <em class="parameter"><code>context_type</code></em>. |
| </p> |
| <div class="variablelist"><table border="0" class="variablelist"> |
| <colgroup> |
| <col align="left" valign="top"> |
| <col> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>context</code></em> :</span></p></td> |
| <td>The <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a>.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>context_type</code></em> :</span></p></td> |
| <td>Context type to check.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td> |
| <a href="http://library.gnome.org/devel/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> if <em class="parameter"><code>context</code></em> has <em class="parameter"><code>context_type</code></em>.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 1.2</p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-context-is-persistent"></a><h3>gst_context_is_persistent ()</h3> |
| <pre class="programlisting"><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a> gst_context_is_persistent (<em class="parameter"><code>const <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> *context</code></em>);</pre> |
| <p> |
| Check if <em class="parameter"><code>context</code></em> is persistent. |
| </p> |
| <div class="variablelist"><table border="0" class="variablelist"> |
| <colgroup> |
| <col align="left" valign="top"> |
| <col> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>context</code></em> :</span></p></td> |
| <td>The <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a>.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td> |
| <a href="http://library.gnome.org/devel/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> if the context is persistent.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 1.2</p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-context-get-structure"></a><h3>gst_context_get_structure ()</h3> |
| <pre class="programlisting">const <a class="link" href="gstreamer-GstStructure.html#GstStructure" title="struct GstStructure"><span class="returnvalue">GstStructure</span></a> * gst_context_get_structure (<em class="parameter"><code>const <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> *context</code></em>);</pre> |
| <p> |
| Access the structure of the context. |
| </p> |
| <div class="variablelist"><table border="0" class="variablelist"> |
| <colgroup> |
| <col align="left" valign="top"> |
| <col> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>context</code></em> :</span></p></td> |
| <td>The <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a>.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>The structure of the context. The structure is |
| still owned by the context, which means that you should not modify it, |
| free it and that the pointer becomes invalid when you free the context. <span class="annotation">[<acronym title="Don't free data after the code is done."><span class="acronym">transfer none</span></acronym>]</span> |
| </td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 1.2</p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-context-writable-structure"></a><h3>gst_context_writable_structure ()</h3> |
| <pre class="programlisting"><a class="link" href="gstreamer-GstStructure.html#GstStructure" title="struct GstStructure"><span class="returnvalue">GstStructure</span></a> * gst_context_writable_structure (<em class="parameter"><code><a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> *context</code></em>);</pre> |
| <p> |
| Get a writable version of the structure. |
| </p> |
| <div class="variablelist"><table border="0" class="variablelist"> |
| <colgroup> |
| <col align="left" valign="top"> |
| <col> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>context</code></em> :</span></p></td> |
| <td>The <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a>.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>The structure of the context. The structure is still |
| owned by the event, which means that you should not free it and |
| that the pointer becomes invalid when you free the event. |
| This function checks if <em class="parameter"><code>context</code></em> is writable.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 1.2</p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-context-make-writable"></a><h3>gst_context_make_writable()</h3> |
| <pre class="programlisting">#define gst_context_make_writable(context) GST_CONTEXT_CAST (gst_mini_object_make_writable (GST_MINI_OBJECT_CAST (context))) |
| </pre> |
| <p> |
| Checks if a context is writable. If not, a writable copy is made and |
| returned. |
| </p> |
| <div class="variablelist"><table border="0" class="variablelist"> |
| <colgroup> |
| <col align="left" valign="top"> |
| <col> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>context</code></em> :</span></p></td> |
| <td>the context to make writable. <span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>a context (possibly a duplicate) that is writable. |
| MT safe. <span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span> |
| </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-context-is-writable"></a><h3>gst_context_is_writable()</h3> |
| <pre class="programlisting">#define gst_context_is_writable(context) gst_mini_object_is_writable (GST_MINI_OBJECT_CAST (context)) |
| </pre> |
| <p> |
| Tests if you can safely write into a context's structure or validly |
| modify the seqnum and timestamp fields. |
| </p> |
| <div class="variablelist"><table border="0" class="variablelist"> |
| <colgroup> |
| <col align="left" valign="top"> |
| <col> |
| </colgroup> |
| <tbody><tr> |
| <td><p><span class="term"><em class="parameter"><code>context</code></em> :</span></p></td> |
| <td>a <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> |
| </td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-context-replace"></a><h3>gst_context_replace ()</h3> |
| <pre class="programlisting"><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a> gst_context_replace (<em class="parameter"><code><a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> **old_context</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> *new_context</code></em>);</pre> |
| <p> |
| Modifies a pointer to a <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> to point to a different <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a>. The |
| modification is done atomically (so this is useful for ensuring thread safety |
| in some cases), and the reference counts are updated appropriately (the old |
| context is unreffed, the new one is reffed). |
| </p> |
| <p> |
| Either <em class="parameter"><code>new_context</code></em> or the <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> pointed to by <em class="parameter"><code>old_context</code></em> may be NULL. |
| </p> |
| <div class="variablelist"><table border="0" class="variablelist"> |
| <colgroup> |
| <col align="left" valign="top"> |
| <col> |
| </colgroup> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>old_context</code></em> :</span></p></td> |
| <td>pointer to a pointer to a <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> |
| to be replaced. <span class="annotation">[<acronym title="Parameter for input and for returning results. Default is transfer full."><span class="acronym">inout</span></acronym>][<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>new_context</code></em> :</span></p></td> |
| <td>pointer to a <a class="link" href="gstreamer-GstContext.html#GstContext" title="GstContext"><span class="type">GstContext</span></a> that will |
| replace the context pointed to by <em class="parameter"><code>old_context</code></em>. <span class="annotation">[<acronym title="NULL is ok, both for passing and for returning."><span class="acronym">allow-none</span></acronym>][<acronym title="Don't free data after the code is done."><span class="acronym">transfer none</span></acronym>]</span> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>TRUE if <em class="parameter"><code>new_context</code></em> was different from <em class="parameter"><code>old_context</code></em> |
| </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| </div> |
| <div class="refsect1"> |
| <a name="gstreamer-GstContext.see-also"></a><h2>See Also</h2> |
| <a class="link" href="gstreamer-GstMiniObject.html#GstMiniObject" title="struct GstMiniObject"><span class="type">GstMiniObject</span></a>, <a class="link" href="GstElement.html" title="GstElement"><span class="type">GstElement</span></a> |
| </div> |
| </div> |
| <div class="footer"> |
| <hr> |
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