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

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  23 <tr><td colspan="5" class="shortcuts">
  24 <a href="#gst-plugins-base-libs-gstxoverlay.synopsis" class="shortcut">Top</a>
  25                    |
  26                   <a href="#gst-plugins-base-libs-gstxoverlay.description" class="shortcut">Description</a>
  27                    |
  28                   <a href="#gst-plugins-base-libs-gstxoverlay.object-hierarchy" class="shortcut">Object Hierarchy</a>
  29                    |
  30                   <a href="#gst-plugins-base-libs-gstxoverlay.prerequisites" class="shortcut">Prerequisites</a>
  31 </td></tr>
  32 </table>
  33 <div class="refentry">
  34 <a name="gst-plugins-base-libs-gstxoverlay"></a><div class="titlepage"></div>
  35 <div class="refnamediv"><table width="100%"><tr>
  36 <td valign="top">
  37 <h2><span class="refentrytitle"><a name="gst-plugins-base-libs-gstxoverlay.top_of_page"></a>gstxoverlay</span></h2>
  38 <p>gstxoverlay — Interface for setting/getting a Window on elements
  39 supporting it</p>
  40 </td>
  41 <td valign="top" align="right"></td>
  42 </tr></table></div>
  43 <div class="refsynopsisdiv">
  44 <a name="gst-plugins-base-libs-gstxoverlay.synopsis"></a><h2>Synopsis</h2>
  45 <a name="GstXOverlay"></a><pre class="synopsis">
  46 #include &lt;gst/interfaces/xoverlay.h&gt;
  47
  48                     <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay-struct" title="GstXOverlay">GstXOverlay</a>;
  49 struct              <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlayClass" title="struct GstXOverlayClass">GstXOverlayClass</a>;
  50 <span class="returnvalue">void</span>                <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#gst-x-overlay-set-xwindow-id" title="gst_x_overlay_set_xwindow_id ()">gst_x_overlay_set_xwindow_id</a>        (<em class="parameter"><code><a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> *overlay</code></em>,
  51                                                          <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gulong"><span class="type">gulong</span></a> xwindow_id</code></em>);
  52 <span class="returnvalue">void</span>                <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#gst-x-overlay-got-xwindow-id" title="gst_x_overlay_got_xwindow_id ()">gst_x_overlay_got_xwindow_id</a>        (<em class="parameter"><code><a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> *overlay</code></em>,
  53                                                          <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gulong"><span class="type">gulong</span></a> xwindow_id</code></em>);
  54 <span class="returnvalue">void</span>                <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#gst-x-overlay-got-window-handle" title="gst_x_overlay_got_window_handle ()">gst_x_overlay_got_window_handle</a>     (<em class="parameter"><code><a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> *overlay</code></em>,
  55                                                          <em class="parameter"><code><span class="type">guintptr</span> handle</code></em>);
  56 <span class="returnvalue">void</span>                <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#gst-x-overlay-set-window-handle" title="gst_x_overlay_set_window_handle ()">gst_x_overlay_set_window_handle</a>     (<em class="parameter"><code><a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> *overlay</code></em>,
  57                                                          <em class="parameter"><code><span class="type">guintptr</span> handle</code></em>);
  58 <span class="returnvalue">void</span>                <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#gst-x-overlay-prepare-xwindow-id" title="gst_x_overlay_prepare_xwindow_id ()">gst_x_overlay_prepare_xwindow_id</a>    (<em class="parameter"><code><a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> *overlay</code></em>);
  59 <span class="returnvalue">void</span>                <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#gst-x-overlay-expose" title="gst_x_overlay_expose ()">gst_x_overlay_expose</a>                (<em class="parameter"><code><a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> *overlay</code></em>);
  60 <span class="returnvalue">void</span>                <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#gst-x-overlay-handle-events" title="gst_x_overlay_handle_events ()">gst_x_overlay_handle_events</a>         (<em class="parameter"><code><a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> *overlay</code></em>,
  61                                                          <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> handle_events</code></em>);
  62 <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>            <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#gst-x-overlay-set-render-rectangle" title="gst_x_overlay_set_render_rectangle ()">gst_x_overlay_set_render_rectangle</a>  (<em class="parameter"><code><a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> *overlay</code></em>,
  63                                                          <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gint"><span class="type">gint</span></a> x</code></em>,
  64                                                          <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gint"><span class="type">gint</span></a> y</code></em>,
  65                                                          <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gint"><span class="type">gint</span></a> width</code></em>,
  66                                                          <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gint"><span class="type">gint</span></a> height</code></em>);
  67 </pre>
  68 </div>
  69 <div class="refsect1">
  70 <a name="gst-plugins-base-libs-gstxoverlay.object-hierarchy"></a><h2>Object Hierarchy</h2>
  71 <pre class="synopsis">
  72   GInterface
  73    +----GstXOverlay
  74 </pre>
  75 </div>
  76 <div class="refsect1">
  77 <a name="gst-plugins-base-libs-gstxoverlay.prerequisites"></a><h2>Prerequisites</h2>
  78 <p>
  79 GstXOverlay requires
  80  <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstImplementsInterface.html">GstImplementsInterface</a> and  <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstElement.html">GstElement</a>.</p>
  81 </div>
  82 <div class="refsect1">
  83 <a name="gst-plugins-base-libs-gstxoverlay.description"></a><h2>Description</h2>
  84 <p>
  85 </p>
  86 <div class="refsect2">
  87 <a name="idp17754944"></a><p>
  88 The XOverlay interface is used for 2 main purposes :
  89 </p>
  90 <div class="itemizedlist"><ul class="itemizedlist" type="disc">
  91 <li class="listitem"><p>
  92 To get a grab on the Window where the video sink element is going to render.
  93 This is achieved by either being informed about the Window identifier that
  94 the video sink element generated, or by forcing the video sink element to use
  95 a specific Window identifier for rendering.
  96 </p></li>
  97 <li class="listitem"><p>
  98 To force a redrawing of the latest video frame the video sink element
  99 displayed on the Window. Indeed if the <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstPipeline.html"><span class="type">GstPipeline</span></a> is in <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstElement.html#GST-STATE-PAUSED:CAPS"><span class="type">GST_STATE_PAUSED</span></a>
 100 state, moving the Window around will damage its content. Application
 101 developers will want to handle the Expose events themselves and force the
 102 video sink element to refresh the Window's content.
 103 </p></li>
 104 </ul></div>
 105 <p>
 106 </p>
 107 <p>
 108 Using the Window created by the video sink is probably the simplest scenario,
 109 in some cases, though, it might not be flexible enough for application
 110 developers if they need to catch events such as mouse moves and button
 111 clicks.
 112 </p>
 113 <p>
 114 Setting a specific Window identifier on the video sink element is the most
 115 flexible solution but it has some issues. Indeed the application needs to set
 116 its Window identifier at the right time to avoid internal Window creation
 117 from the video sink element. To solve this issue a <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstMessage.html#GstMessage"><span class="type">GstMessage</span></a> is posted on
 118 the bus to inform the application that it should set the Window identifier
 119 immediately. Here is an example on how to do that correctly:
 120 </p>
 121 <div class="informalexample">
 122   <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
 123     <tbody>
 124       <tr>
 125         <td class="listing_lines" align="right"><pre>1
 126 2
 127 3
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 156 32
 157 33
 158 34</pre></td>
 159         <td class="listing_code"><pre class="programlisting"><span class="gtkdoc kwb">static</span> GstBusSyncReply
 160 <span class="function">create_window</span> <span class="gtkdoc opt">(</span>GstBus <span class="gtkdoc opt">*</span> bus<span class="gtkdoc opt">,</span> GstMessage <span class="gtkdoc opt">*</span> message<span class="gtkdoc opt">,</span> GstPipeline <span class="gtkdoc opt">*</span> pipeline<span class="gtkdoc opt">)</span>
 161 <span class="gtkdoc opt">{</span>
 162  <span class="gtkdoc slc">// ignore anything but 'prepare-xwindow-id' element messages</span>
 163  <span class="keyword">if</span> <span class="gtkdoc opt">(</span><span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstMessage.html#GST-MESSAGE-TYPE:CAPS">GST_MESSAGE_TYPE</a></span> <span class="gtkdoc opt">(</span>message<span class="gtkdoc opt">) !=</span> GST_MESSAGE_ELEMENT<span class="gtkdoc opt">)</span>
 164    <span class="keyword">return</span> GST_BUS_PASS<span class="gtkdoc opt">;</span>
 165
 166  <span class="keyword">if</span> <span class="gtkdoc opt">(!</span><span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstStructure.html#gst-structure-has-name">gst_structure_has_name</a></span> <span class="gtkdoc opt">(</span>message<span class="gtkdoc opt">-&gt;</span>structure<span class="gtkdoc opt">,</span> <span class="string">&quot;prepare-xwindow-id&quot;</span><span class="gtkdoc opt">))</span>
 167    <span class="keyword">return</span> GST_BUS_PASS<span class="gtkdoc opt">;</span>
 168
 169  win <span class="gtkdoc opt">=</span> <span class="function">XCreateSimpleWindow</span> <span class="gtkdoc opt">(</span>disp<span class="gtkdoc opt">,</span> root<span class="gtkdoc opt">,</span> <span class="number">0</span><span class="gtkdoc opt">,</span> <span class="number">0</span><span class="gtkdoc opt">,</span> <span class="number">320</span><span class="gtkdoc opt">,</span> <span class="number">240</span><span class="gtkdoc opt">,</span> <span class="number">0</span><span class="gtkdoc opt">,</span> <span class="number">0</span><span class="gtkdoc opt">,</span> <span class="number">0</span><span class="gtkdoc opt">);</span>
 170
 171  <span class="function">XSetWindowBackgroundPixmap</span> <span class="gtkdoc opt">(</span>disp<span class="gtkdoc opt">,</span> win<span class="gtkdoc opt">,</span> None<span class="gtkdoc opt">);</span>
 172
 173  <span class="function">XMapRaised</span> <span class="gtkdoc opt">(</span>disp<span class="gtkdoc opt">,</span> win<span class="gtkdoc opt">);</span>
 174
 175  <span class="function">XSync</span> <span class="gtkdoc opt">(</span>disp<span class="gtkdoc opt">,</span> FALSE<span class="gtkdoc opt">);</span>
 176
 177  <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gst-plugins-base-libs/html/gst-plugins-base-libs-gstxoverlay.html#gst-x-overlay-set-window-handle">gst_x_overlay_set_window_handle</a></span> <span class="gtkdoc opt">(</span><span class="function">GST_X_OVERLAY</span> <span class="gtkdoc opt">(</span><span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstMessage.html#GST-MESSAGE-SRC:CAPS">GST_MESSAGE_SRC</a></span> <span class="gtkdoc opt">(</span>message<span class="gtkdoc opt">)),</span>
 178      win<span class="gtkdoc opt">);</span>
 179
 180  <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstMessage.html#gst-message-unref">gst_message_unref</a></span> <span class="gtkdoc opt">(</span>message<span class="gtkdoc opt">);</span>
 181
 182  <span class="keyword">return</span> GST_BUS_DROP<span class="gtkdoc opt">;</span>
 183 <span class="gtkdoc opt">}</span>
 184 <span class="gtkdoc opt">...</span>
 185 <span class="gtkdoc kwb">int</span>
 186 <span class="function">main</span> <span class="gtkdoc opt">(</span><span class="gtkdoc kwb">int</span> argc<span class="gtkdoc opt">,</span> <span class="gtkdoc kwb">char</span> <span class="gtkdoc opt">**</span>argv<span class="gtkdoc opt">)</span>
 187 <span class="gtkdoc opt">{</span>
 188 <span class="gtkdoc opt">...</span>
 189  bus <span class="gtkdoc opt">=</span> <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstPipeline.html#gst-pipeline-get-bus">gst_pipeline_get_bus</a></span> <span class="gtkdoc opt">(</span><span class="function">GST_PIPELINE</span> <span class="gtkdoc opt">(</span>pipeline<span class="gtkdoc opt">));</span>
 190  <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstBus.html#gst-bus-set-sync-handler">gst_bus_set_sync_handler</a></span> <span class="gtkdoc opt">(</span>bus<span class="gtkdoc opt">, (</span>GstBusSyncHandler<span class="gtkdoc opt">)</span> create_window<span class="gtkdoc opt">,</span> pipeline<span class="gtkdoc opt">);</span>
 191 <span class="gtkdoc opt">...</span>
 192 <span class="gtkdoc opt">}</span></pre></td>
 193       </tr>
 194     </tbody>
 195   </table>
 196 </div>
 197
 198 <p>
 199 </p>
 200 </div>
 201 <p>
 202 </p>
 203 <hr>
 204 <div class="refsect2">
 205 <a name="idp17764272"></a><h3>Two basic usage scenarios</h3>
 206 <p>
 207 There are two basic usage scenarios: in the simplest case, the application
 208 knows exactly what particular element is used for video output, which is
 209 usually the case when the application creates the videosink to use
 210 (e.g. <span class="type">xvimagesink</span>, <span class="type">ximagesink</span>, etc.) itself; in this case, the application
 211 can just create the videosink element, create and realize the window to
 212 render the video on and then call <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#gst-x-overlay-set-window-handle" title="gst_x_overlay_set_window_handle ()"><code class="function">gst_x_overlay_set_window_handle()</code></a> directly
 213 with the XID or native window handle, before starting up the pipeline.
 214 </p>
 215 <p>
 216 In the other and more common case, the application does not know in advance
 217 what GStreamer video sink element will be used for video output. This is
 218 usually the case when an element such as <span class="type">autovideosink</span> or <span class="type">gconfvideosink</span>
 219 is used. In this case, the video sink element itself is created
 220 asynchronously from a GStreamer streaming thread some time after the
 221 pipeline has been started up. When that happens, however, the video sink
 222 will need to know right then whether to render onto an already existing
 223 application window or whether to create its own window. This is when it
 224 posts a prepare-xwindow-id message, and that is also why this message needs
 225 to be handled in a sync bus handler which will be called from the streaming
 226 thread directly (because the video sink will need an answer right then).
 227 </p>
 228 <p>
 229 As response to the prepare-xwindow-id element message in the bus sync
 230 handler, the application may use <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#gst-x-overlay-set-window-handle" title="gst_x_overlay_set_window_handle ()"><code class="function">gst_x_overlay_set_window_handle()</code></a> to tell
 231 the video sink to render onto an existing window surface. At this point the
 232 application should already have obtained the window handle / XID, so it
 233 just needs to set it. It is generally not advisable to call any GUI toolkit
 234 functions or window system functions from the streaming thread in which the
 235 prepare-xwindow-id message is handled, because most GUI toolkits and
 236 windowing systems are not thread-safe at all and a lot of care would be
 237 required to co-ordinate the toolkit and window system calls of the
 238 different threads (Gtk+ users please note: prior to Gtk+ 2.18
 239 <a href="http://library.gnome.org/devel/gdk/gdk3-X-Window-System-Interaction.html#GDK-WINDOW-XID:CAPS"><code class="function">GDK_WINDOW_XID()</code></a> was just a simple structure access, so generally fine to do
 240 within the bus sync handler; this macro was changed to a function call in
 241 Gtk+ 2.18 and later, which is likely to cause problems when called from a
 242 sync handler; see below for a better approach without <a href="http://library.gnome.org/devel/gdk/gdk3-X-Window-System-Interaction.html#GDK-WINDOW-XID:CAPS"><code class="function">GDK_WINDOW_XID()</code></a>
 243 used in the callback).
 244 </p>
 245 </div>
 246 <p>
 247 </p>
 248 <hr>
 249 <div class="refsect2">
 250 <a name="idp17776432"></a><h3>GstXOverlay and Gtk+</h3>
 251 <p>
 252 </p>
 253 <div class="informalexample">
 254   <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
 255     <tbody>
 256       <tr>
 257         <td class="listing_lines" align="right"><pre>1
 258 2
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 336 80
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 338 82
 339 83</pre></td>
 340         <td class="listing_code"><pre class="programlisting"><span class="gtkdoc ppc">#include &lt;gst/interfaces/xoverlay.h&gt;</span>
 341 <span class="gtkdoc ppc">#include &lt;gtk/gtk.h&gt;</span>
 342 <span class="gtkdoc ppc">#ifdef GDK_WINDOWING_X11</span>
 343 <span class="gtkdoc ppc">#include &lt;gdk/gdkx.h&gt;</span>  <span class="gtkdoc slc">// for GDK_WINDOW_XID</span>
 344 <span class="gtkdoc ppc"></span><span class="gtkdoc ppc">#endif</span>
 345 <span class="gtkdoc opt">...</span>
 346 <span class="gtkdoc kwb">static</span> gulong video_window_xid <span class="gtkdoc opt">=</span> <span class="number">0</span><span class="gtkdoc opt">;</span>
 347 <span class="gtkdoc opt">...</span>
 348 <span class="gtkdoc kwb">static</span> GstBusSyncReply
 349 <span class="function">bus_sync_handler</span> <span class="gtkdoc opt">(</span>GstBus <span class="gtkdoc opt">*</span> bus<span class="gtkdoc opt">,</span> GstMessage <span class="gtkdoc opt">*</span> message<span class="gtkdoc opt">,</span> gpointer user_data<span class="gtkdoc opt">)</span>
 350 <span class="gtkdoc opt">{</span>
 351  <span class="gtkdoc slc">// ignore anything but 'prepare-xwindow-id' element messages</span>
 352  <span class="keyword">if</span> <span class="gtkdoc opt">(</span><span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstMessage.html#GST-MESSAGE-TYPE:CAPS">GST_MESSAGE_TYPE</a></span> <span class="gtkdoc opt">(</span>message<span class="gtkdoc opt">) !=</span> GST_MESSAGE_ELEMENT<span class="gtkdoc opt">)</span>
 353    <span class="keyword">return</span> GST_BUS_PASS<span class="gtkdoc opt">;</span>
 354  <span class="keyword">if</span> <span class="gtkdoc opt">(!</span><span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstStructure.html#gst-structure-has-name">gst_structure_has_name</a></span> <span class="gtkdoc opt">(</span>message<span class="gtkdoc opt">-&gt;</span>structure<span class="gtkdoc opt">,</span> <span class="string">&quot;prepare-xwindow-id&quot;</span><span class="gtkdoc opt">))</span>
 355    <span class="keyword">return</span> GST_BUS_PASS<span class="gtkdoc opt">;</span>
 356
 357  <span class="keyword">if</span> <span class="gtkdoc opt">(</span>video_window_xid <span class="gtkdoc opt">!=</span> <span class="number">0</span><span class="gtkdoc opt">) {</span>
 358    GstXOverlay <span class="gtkdoc opt">*</span>xoverlay<span class="gtkdoc opt">;</span>
 359
 360    <span class="gtkdoc slc">// GST_MESSAGE_SRC (message) will be the video sink element</span>
 361    xoverlay <span class="gtkdoc opt">=</span> <span class="function">GST_X_OVERLAY</span> <span class="gtkdoc opt">(</span><span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstMessage.html#GST-MESSAGE-SRC:CAPS">GST_MESSAGE_SRC</a></span> <span class="gtkdoc opt">(</span>message<span class="gtkdoc opt">));</span>
 362    <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gst-plugins-base-libs/html/gst-plugins-base-libs-gstxoverlay.html#gst-x-overlay-set-window-handle">gst_x_overlay_set_window_handle</a></span> <span class="gtkdoc opt">(</span>xoverlay<span class="gtkdoc opt">,</span> video_window_xid<span class="gtkdoc opt">);</span>
 363  <span class="gtkdoc opt">}</span> <span class="keyword">else</span> <span class="gtkdoc opt">{</span>
 364    <span class="function"><a href="http://library.gnome.org/devel/glib/unstable/glib-Message-Logging.html#g-warning">g_warning</a></span> <span class="gtkdoc opt">(</span><span class="string">&quot;Should have obtained video_window_xid by now!&quot;</span><span class="gtkdoc opt">);</span>
 365  <span class="gtkdoc opt">}</span>
 366
 367  <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstMessage.html#gst-message-unref">gst_message_unref</a></span> <span class="gtkdoc opt">(</span>message<span class="gtkdoc opt">);</span>
 368  <span class="keyword">return</span> GST_BUS_DROP<span class="gtkdoc opt">;</span>
 369 <span class="gtkdoc opt">}</span>
 370 <span class="gtkdoc opt">...</span>
 371 <span class="gtkdoc kwb">static void</span>
 372 <span class="function">video_widget_realize_cb</span> <span class="gtkdoc opt">(</span>GtkWidget <span class="gtkdoc opt">*</span> widget<span class="gtkdoc opt">,</span> gpointer data<span class="gtkdoc opt">)</span>
 373 <span class="gtkdoc opt">{</span>
 374 <span class="gtkdoc ppc">#if GTK_CHECK_VERSION(2,18,0)</span>
 375   <span class="gtkdoc slc">// This is here just for pedagogical purposes, GDK_WINDOW_XID will call</span>
 376   <span class="gtkdoc slc">// it as well in newer Gtk versions</span>
 377   <span class="keyword">if</span> <span class="gtkdoc opt">(!</span><span class="function"><a href="http://library.gnome.org/devel/gdk/gdk3-Windows.html#gdk-window-ensure-native">gdk_window_ensure_native</a></span> <span class="gtkdoc opt">(</span>widget<span class="gtkdoc opt">-&gt;</span>window<span class="gtkdoc opt">))</span>
 378     <span class="function"><a href="http://library.gnome.org/devel/glib/unstable/glib-Message-Logging.html#g-error">g_error</a></span> <span class="gtkdoc opt">(</span><span class="string">&quot;Couldn't create native window needed for GstXOverlay!&quot;</span><span class="gtkdoc opt">);</span>
 379 <span class="gtkdoc ppc">#endif</span>
 380
 381 <span class="gtkdoc ppc">#ifdef GDK_WINDOWING_X11</span>
 382   video_window_xid <span class="gtkdoc opt">=</span> <span class="function"><a href="http://library.gnome.org/devel/gdk/gdk3-X-Window-System-Interaction.html#GDK-WINDOW-XID:CAPS">GDK_WINDOW_XID</a></span> <span class="gtkdoc opt">(</span><span class="function"><a href="http://library.gnome.org/devel/gtk/GtkWidget.html#gtk-widget-get-window">gtk_widget_get_window</a></span> <span class="gtkdoc opt">(</span>video_window<span class="gtkdoc opt">));</span>
 383 <span class="gtkdoc ppc">#endif</span>
 384 <span class="gtkdoc opt">}</span>
 385 <span class="gtkdoc opt">...</span>
 386 <span class="gtkdoc kwb">int</span>
 387 <span class="function">main</span> <span class="gtkdoc opt">(</span><span class="gtkdoc kwb">int</span> argc<span class="gtkdoc opt">,</span> <span class="gtkdoc kwb">char</span> <span class="gtkdoc opt">**</span>argv<span class="gtkdoc opt">)</span>
 388 <span class="gtkdoc opt">{</span>
 389   GtkWidget <span class="gtkdoc opt">*</span>video_window<span class="gtkdoc opt">;</span>
 390   GtkWidget <span class="gtkdoc opt">*</span>app_window<span class="gtkdoc opt">;</span>
 391   <span class="gtkdoc opt">...</span>
 392   app_window <span class="gtkdoc opt">=</span> <span class="function"><a href="http://library.gnome.org/devel/gtk/GtkWindow.html#gtk-window-new">gtk_window_new</a></span> <span class="gtkdoc opt">(</span>GTK_WINDOW_TOPLEVEL<span class="gtkdoc opt">);</span>
 393   <span class="gtkdoc opt">...</span>
 394   video_window <span class="gtkdoc opt">=</span> <span class="function"><a href="http://library.gnome.org/devel/gtk/GtkDrawingArea.html#gtk-drawing-area-new">gtk_drawing_area_new</a></span> <span class="gtkdoc opt">();</span>
 395   <span class="function"><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Signals.html#g-signal-connect">g_signal_connect</a></span> <span class="gtkdoc opt">(</span>video_window<span class="gtkdoc opt">,</span> <span class="string">&quot;realize&quot;</span><span class="gtkdoc opt">,</span>
 396       <span class="function"><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Closures.html#G-CALLBACK:CAPS">G_CALLBACK</a></span> <span class="gtkdoc opt">(</span>video_widget_realize_cb<span class="gtkdoc opt">),</span> NULL<span class="gtkdoc opt">);</span>
 397   <span class="function"><a href="http://library.gnome.org/devel/gtk/GtkWidget.html#gtk-widget-set-double-buffered">gtk_widget_set_double_buffered</a></span> <span class="gtkdoc opt">(</span>video_window<span class="gtkdoc opt">,</span> FALSE<span class="gtkdoc opt">);</span>
 398   <span class="gtkdoc opt">...</span>
 399   <span class="gtkdoc slc">// usually the video_window will not be directly embedded into the</span>
 400   <span class="gtkdoc slc">// application window like this, but there will be many other widgets</span>
 401   <span class="gtkdoc slc">// and the video window will be embedded in one of them instead</span>
 402   <span class="function"><a href="http://library.gnome.org/devel/gtk/GtkContainer.html#gtk-container-add">gtk_container_add</a></span> <span class="gtkdoc opt">(</span><span class="function">GTK_CONTAINER</span> <span class="gtkdoc opt">(</span>ap_window<span class="gtkdoc opt">),</span> video_window<span class="gtkdoc opt">);</span>
 403   <span class="gtkdoc opt">...</span>
 404   <span class="gtkdoc slc">// show the GUI</span>
 405   <span class="function"><a href="http://library.gnome.org/devel/gtk/GtkWidget.html#gtk-widget-show-all">gtk_widget_show_all</a></span> <span class="gtkdoc opt">(</span>app_window<span class="gtkdoc opt">);</span>
 406
 407   <span class="gtkdoc slc">// realize window now so that the video window gets created and we can</span>
 408   <span class="gtkdoc slc">// obtain its XID before the pipeline is started up and the videosink</span>
 409   <span class="gtkdoc slc">// asks for the XID of the window to render onto</span>
 410   <span class="function"><a href="http://library.gnome.org/devel/gtk/GtkWidget.html#gtk-widget-realize">gtk_widget_realize</a></span> <span class="gtkdoc opt">(</span>video_window<span class="gtkdoc opt">);</span>
 411
 412   <span class="gtkdoc slc">// we should have the XID now</span>
 413   <span class="function"><a href="http://library.gnome.org/devel/glib/unstable/glib-Testing.html#g-assert">g_assert</a></span> <span class="gtkdoc opt">(</span>video_window_xid <span class="gtkdoc opt">!=</span> <span class="number">0</span><span class="gtkdoc opt">);</span>
 414   <span class="gtkdoc opt">...</span>
 415   <span class="gtkdoc slc">// set up sync handler for setting the xid once the pipeline is started</span>
 416   bus <span class="gtkdoc opt">=</span> <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstPipeline.html#gst-pipeline-get-bus">gst_pipeline_get_bus</a></span> <span class="gtkdoc opt">(</span><span class="function">GST_PIPELINE</span> <span class="gtkdoc opt">(</span>pipeline<span class="gtkdoc opt">));</span>
 417   <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstBus.html#gst-bus-set-sync-handler">gst_bus_set_sync_handler</a></span> <span class="gtkdoc opt">(</span>bus<span class="gtkdoc opt">, (</span>GstBusSyncHandler<span class="gtkdoc opt">)</span> bus_sync_handler<span class="gtkdoc opt">,</span> NULL<span class="gtkdoc opt">);</span>
 418   <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstObject.html#gst-object-unref">gst_object_unref</a></span> <span class="gtkdoc opt">(</span>bus<span class="gtkdoc opt">);</span>
 419   <span class="gtkdoc opt">...</span>
 420   <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstElement.html#gst-element-set-state">gst_element_set_state</a></span> <span class="gtkdoc opt">(</span>pipeline<span class="gtkdoc opt">,</span> GST_STATE_PLAYING<span class="gtkdoc opt">);</span>
 421   <span class="gtkdoc opt">...</span>
 422 <span class="gtkdoc opt">}</span></pre></td>
 423       </tr>
 424     </tbody>
 425   </table>
 426 </div>
 427
 428 <p>
 429 </p>
 430 </div>
 431 <p>
 432 </p>
 433 <hr>
 434 <div class="refsect2">
 435 <a name="idp17781264"></a><h3>GstXOverlay and Qt</h3>
 436 <p>
 437 </p>
 438 <div class="informalexample">
 439   <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
 440     <tbody>
 441       <tr>
 442         <td class="listing_lines" align="right"><pre>1
 443 2
 444 3
 445 4
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 447 6
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 494 53</pre></td>
 495         <td class="listing_code"><pre class="programlisting"><span class="gtkdoc ppc">#include &lt;glib.h&gt;</span>
 496 <span class="gtkdoc ppc">#include &lt;gst/gst.h&gt;</span>
 497 <span class="gtkdoc ppc">#include &lt;gst/interfaces/xoverlay.h&gt;</span>
 498
 499 <span class="gtkdoc ppc">#include &lt;QApplication&gt;</span>
 500 <span class="gtkdoc ppc">#include &lt;QTimer&gt;</span>
 501 <span class="gtkdoc ppc">#include &lt;QWidget&gt;</span>
 502
 503 <span class="gtkdoc kwb">int</span> <span class="function">main</span><span class="gtkdoc opt">(</span><span class="gtkdoc kwb">int</span> argc<span class="gtkdoc opt">,</span> <span class="gtkdoc kwb">char</span> <span class="gtkdoc opt">*</span>argv<span class="gtkdoc opt">[])</span>
 504 <span class="gtkdoc opt">{</span>
 505   <span class="keyword">if</span> <span class="gtkdoc opt">(!</span><span class="function"><a href="http://library.gnome.org/devel/glib/unstable/glib-Threads.html#g-thread-supported">g_thread_supported</a></span> <span class="gtkdoc opt">())</span>
 506     <span class="function"><a href="http://library.gnome.org/devel/glib/unstable/glib-Threads.html#g-thread-init">g_thread_init</a></span> <span class="gtkdoc opt">(</span>NULL<span class="gtkdoc opt">);</span>
 507
 508   <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-Gst.html#gst-init">gst_init</a></span> <span class="gtkdoc opt">(&amp;</span>argc<span class="gtkdoc opt">, &amp;</span>argv<span class="gtkdoc opt">);</span>
 509   QApplication <span class="function">app</span><span class="gtkdoc opt">(</span>argc<span class="gtkdoc opt">,</span> argv<span class="gtkdoc opt">);</span>
 510   app<span class="gtkdoc opt">.</span><span class="function">connect</span><span class="gtkdoc opt">(&amp;</span>app<span class="gtkdoc opt">,</span> <span class="function">SIGNAL</span><span class="gtkdoc opt">(</span><span class="function">lastWindowClosed</span><span class="gtkdoc opt">()), &amp;</span>app<span class="gtkdoc opt">,</span> <span class="function">SLOT</span><span class="gtkdoc opt">(</span><span class="function">quit</span> <span class="gtkdoc opt">()));</span>
 511
 512   <span class="gtkdoc slc">// prepare the pipeline</span>
 513
 514   GstElement <span class="gtkdoc opt">*</span>pipeline <span class="gtkdoc opt">=</span> <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstPipeline.html#gst-pipeline-new">gst_pipeline_new</a></span> <span class="gtkdoc opt">(</span><span class="string">&quot;xvoverlay&quot;</span><span class="gtkdoc opt">);</span>
 515   GstElement <span class="gtkdoc opt">*</span>src <span class="gtkdoc opt">=</span> <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstElementFactory.html#gst-element-factory-make">gst_element_factory_make</a></span> <span class="gtkdoc opt">(</span><span class="string">&quot;videotestsrc&quot;</span><span class="gtkdoc opt">,</span> NULL<span class="gtkdoc opt">);</span>
 516   GstElement <span class="gtkdoc opt">*</span>sink <span class="gtkdoc opt">=</span> <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstElementFactory.html#gst-element-factory-make">gst_element_factory_make</a></span> <span class="gtkdoc opt">(</span><span class="string">&quot;xvimagesink&quot;</span><span class="gtkdoc opt">,</span> NULL<span class="gtkdoc opt">);</span>
 517   <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstBin.html#gst-bin-add-many">gst_bin_add_many</a></span> <span class="gtkdoc opt">(</span><span class="function">GST_BIN</span> <span class="gtkdoc opt">(</span>pipeline<span class="gtkdoc opt">),</span> src<span class="gtkdoc opt">,</span> sink<span class="gtkdoc opt">,</span> NULL<span class="gtkdoc opt">);</span>
 518   <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstElement.html#gst-element-link">gst_element_link</a></span> <span class="gtkdoc opt">(</span>src<span class="gtkdoc opt">,</span> sink<span class="gtkdoc opt">);</span>
 519
 520   <span class="gtkdoc slc">// prepare the ui</span>
 521
 522   QWidget window<span class="gtkdoc opt">;</span>
 523   window<span class="gtkdoc opt">.</span><span class="function">resize</span><span class="gtkdoc opt">(</span><span class="number">320</span><span class="gtkdoc opt">,</span> <span class="number">240</span><span class="gtkdoc opt">);</span>
 524   window<span class="gtkdoc opt">.</span><span class="function">show</span><span class="gtkdoc opt">();</span>
 525
 526   WId xwinid <span class="gtkdoc opt">=</span> window<span class="gtkdoc opt">.</span><span class="function">winId</span><span class="gtkdoc opt">();</span>
 527   <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gst-plugins-base-libs/html/gst-plugins-base-libs-gstxoverlay.html#gst-x-overlay-set-window-handle">gst_x_overlay_set_window_handle</a></span> <span class="gtkdoc opt">(</span><span class="function">GST_X_OVERLAY</span> <span class="gtkdoc opt">(</span>sink<span class="gtkdoc opt">),</span> xwinid<span class="gtkdoc opt">);</span>
 528
 529   <span class="gtkdoc slc">// run the pipeline</span>
 530
 531   GstStateChangeReturn sret <span class="gtkdoc opt">=</span> <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstElement.html#gst-element-set-state">gst_element_set_state</a></span> <span class="gtkdoc opt">(</span>pipeline<span class="gtkdoc opt">,</span>
 532       GST_STATE_PLAYING<span class="gtkdoc opt">);</span>
 533   <span class="keyword">if</span> <span class="gtkdoc opt">(</span>sret <span class="gtkdoc opt">==</span> GST_STATE_CHANGE_FAILURE<span class="gtkdoc opt">) {</span>
 534     <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstElement.html#gst-element-set-state">gst_element_set_state</a></span> <span class="gtkdoc opt">(</span>pipeline<span class="gtkdoc opt">,</span> GST_STATE_NULL<span class="gtkdoc opt">);</span>
 535     <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstObject.html#gst-object-unref">gst_object_unref</a></span> <span class="gtkdoc opt">(</span>pipeline<span class="gtkdoc opt">);</span>
 536     <span class="gtkdoc slc">// Exit application</span>
 537     QTimer<span class="gtkdoc opt">::</span><span class="function">singleShot</span><span class="gtkdoc opt">(</span><span class="number">0</span><span class="gtkdoc opt">,</span> QApplication<span class="gtkdoc opt">::</span><span class="function">activeWindow</span><span class="gtkdoc opt">(),</span> <span class="function">SLOT</span><span class="gtkdoc opt">(</span><span class="function">quit</span><span class="gtkdoc opt">()));</span>
 538   <span class="gtkdoc opt">}</span>
 539
 540   <span class="gtkdoc kwb">int</span> ret <span class="gtkdoc opt">=</span> app<span class="gtkdoc opt">.</span><span class="function">exec</span><span class="gtkdoc opt">();</span>
 541
 542   window<span class="gtkdoc opt">.</span><span class="function">hide</span><span class="gtkdoc opt">();</span>
 543   <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstElement.html#gst-element-set-state">gst_element_set_state</a></span> <span class="gtkdoc opt">(</span>pipeline<span class="gtkdoc opt">,</span> GST_STATE_NULL<span class="gtkdoc opt">);</span>
 544   <span class="function"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstObject.html#gst-object-unref">gst_object_unref</a></span> <span class="gtkdoc opt">(</span>pipeline<span class="gtkdoc opt">);</span>
 545
 546   <span class="keyword">return</span> ret<span class="gtkdoc opt">;</span>
 547 <span class="gtkdoc opt">}</span></pre></td>
 548       </tr>
 549     </tbody>
 550   </table>
 551 </div>
 552
 553 <p>
 554 </p>
 555 </div>
 556 <p>
 557 </p>
 558 </div>
 559 <div class="refsect1">
 560 <a name="gst-plugins-base-libs-gstxoverlay.details"></a><h2>Details</h2>
 561 <div class="refsect2">
 562 <a name="GstXOverlay-struct"></a><h3>GstXOverlay</h3>
 563 <pre class="programlisting">typedef struct _GstXOverlay GstXOverlay;</pre>
 564 <p>
 565 Opaque <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> data structure.
 566 </p>
 567 </div>
 568 <hr>
 569 <div class="refsect2">
 570 <a name="GstXOverlayClass"></a><h3>struct GstXOverlayClass</h3>
 571 <pre class="programlisting">struct GstXOverlayClass {
 572   GTypeInterface klass;
 573
 574   /* virtual functions */
 575 #ifndef GST_DISABLE_DEPRECATED
 576   void (* set_xwindow_id)      (GstXOverlay *overlay,
 577                                 gulong       xwindow_id);
 578 #else
 579 #endif
 580 #endif /* not GST_DISABLE_DEPRECATED */
 581
 582   void (* expose)              (GstXOverlay *overlay);
 583
 584   void (* handle_events)       (GstXOverlay *overlay,
 585                                 gboolean     handle_events);
 586
 587   void (* set_render_rectangle) (GstXOverlay *overlay,
 588                                  gint x, gint y,
 589                                  gint width, gint height);
 590
 591   void (* set_window_handle)   (GstXOverlay *overlay,
 592                                 guintptr    handle);
 593 };
 594 </pre>
 595 <p>
 596 <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> interface
 597 </p>
 598 <div class="variablelist"><table border="0">
 599 <col align="left" valign="top">
 600 <tbody>
 601 <tr>
 602 <td><p><span class="term"><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Type-Information.html#GTypeInterface"><span class="type">GTypeInterface</span></a> <em class="structfield"><code><a name="GstXOverlayClass.klass"></a>klass</code></em>;</span></p></td>
 603 <td>parent interface type.</td>
 604 </tr>
 605 <tr>
 606 <td><p><span class="term"><em class="structfield"><code><a name="GstXOverlayClass.set-xwindow-id"></a>set_xwindow_id</code></em> ()</span></p></td>
 607 <td>(deprecated) virtual method to configure the XWindow handle</td>
 608 </tr>
 609 <tr>
 610 <td><p><span class="term"><em class="structfield"><code><a name="GstXOverlayClass.expose"></a>expose</code></em> ()</span></p></td>
 611 <td>virtual method to handle expose events</td>
 612 </tr>
 613 <tr>
 614 <td><p><span class="term"><em class="structfield"><code><a name="GstXOverlayClass.handle-events"></a>handle_events</code></em> ()</span></p></td>
 615 <td>virtual method to handle events</td>
 616 </tr>
 617 <tr>
 618 <td><p><span class="term"><em class="structfield"><code><a name="GstXOverlayClass.set-render-rectangle"></a>set_render_rectangle</code></em> ()</span></p></td>
 619 <td>virtual method to set the render rectangle (since 0.10.29)</td>
 620 </tr>
 621 <tr>
 622 <td><p><span class="term"><em class="structfield"><code><a name="GstXOverlayClass.set-window-handle"></a>set_window_handle</code></em> ()</span></p></td>
 623 <td>virtual method to configure the window handle</td>
 624 </tr>
 625 </tbody>
 626 </table></div>
 627 </div>
 628 <hr>
 629 <div class="refsect2">
 630 <a name="gst-x-overlay-set-xwindow-id"></a><h3>gst_x_overlay_set_xwindow_id ()</h3>
 631 <pre class="programlisting"><span class="returnvalue">void</span>                gst_x_overlay_set_xwindow_id        (<em class="parameter"><code><a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> *overlay</code></em>,
 632                                                          <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gulong"><span class="type">gulong</span></a> xwindow_id</code></em>);</pre>
 633 <div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;">
 634 <h3 class="title">Warning</h3>
 635 <p><code class="literal">gst_x_overlay_set_xwindow_id</code> is deprecated and should not be used in newly-written code. Use <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#gst-x-overlay-set-window-handle" title="gst_x_overlay_set_window_handle ()"><code class="function">gst_x_overlay_set_window_handle()</code></a> instead.</p>
 636 </div>
 637 <p>
 638 This will call the video overlay's set_xwindow_id method. You should
 639 use this method to tell to a XOverlay to display video output to a
 640 specific XWindow. Passing 0 as the <em class="parameter"><code>xwindow_id</code></em> will tell the overlay to
 641 stop using that window and create an internal one.
 642 </p>
 643 <div class="variablelist"><table border="0">
 644 <col align="left" valign="top">
 645 <tbody>
 646 <tr>
 647 <td><p><span class="term"><em class="parameter"><code>overlay</code></em> :</span></p></td>
 648 <td>a <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> to set the window on.</td>
 649 </tr>
 650 <tr>
 651 <td><p><span class="term"><em class="parameter"><code>xwindow_id</code></em> :</span></p></td>
 652 <td>a XID referencing the XWindow.</td>
 653 </tr>
 654 </tbody>
 655 </table></div>
 656 </div>
 657 <hr>
 658 <div class="refsect2">
 659 <a name="gst-x-overlay-got-xwindow-id"></a><h3>gst_x_overlay_got_xwindow_id ()</h3>
 660 <pre class="programlisting"><span class="returnvalue">void</span>                gst_x_overlay_got_xwindow_id        (<em class="parameter"><code><a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> *overlay</code></em>,
 661                                                          <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gulong"><span class="type">gulong</span></a> xwindow_id</code></em>);</pre>
 662 <div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;">
 663 <h3 class="title">Warning</h3>
 664 <p><code class="literal">gst_x_overlay_got_xwindow_id</code> is deprecated and should not be used in newly-written code. Use <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#gst-x-overlay-got-window-handle" title="gst_x_overlay_got_window_handle ()"><code class="function">gst_x_overlay_got_window_handle()</code></a> instead.</p>
 665 </div>
 666 <p>
 667 This will post a "have-xwindow-id" element message on the bus.
 668 </p>
 669 <p>
 670 This function should only be used by video overlay plugin developers.
 671 </p>
 672 <div class="variablelist"><table border="0">
 673 <col align="left" valign="top">
 674 <tbody>
 675 <tr>
 676 <td><p><span class="term"><em class="parameter"><code>overlay</code></em> :</span></p></td>
 677 <td>a <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> which got a XWindow.</td>
 678 </tr>
 679 <tr>
 680 <td><p><span class="term"><em class="parameter"><code>xwindow_id</code></em> :</span></p></td>
 681 <td>a XID referencing the XWindow.</td>
 682 </tr>
 683 </tbody>
 684 </table></div>
 685 </div>
 686 <hr>
 687 <div class="refsect2">
 688 <a name="gst-x-overlay-got-window-handle"></a><h3>gst_x_overlay_got_window_handle ()</h3>
 689 <pre class="programlisting"><span class="returnvalue">void</span>                gst_x_overlay_got_window_handle     (<em class="parameter"><code><a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> *overlay</code></em>,
 690                                                          <em class="parameter"><code><span class="type">guintptr</span> handle</code></em>);</pre>
 691 <p>
 692 This will post a "have-xwindow-id" element message on the bus.
 693 </p>
 694 <p>
 695 This function should only be used by video overlay plugin developers.
 696 </p>
 697 <div class="variablelist"><table border="0">
 698 <col align="left" valign="top">
 699 <tbody>
 700 <tr>
 701 <td><p><span class="term"><em class="parameter"><code>overlay</code></em> :</span></p></td>
 702 <td>a <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> which got a window</td>
 703 </tr>
 704 <tr>
 705 <td><p><span class="term"><em class="parameter"><code>handle</code></em> :</span></p></td>
 706 <td>a platform-specific handle referencing the window</td>
 707 </tr>
 708 </tbody>
 709 </table></div>
 710 </div>
 711 <hr>
 712 <div class="refsect2">
 713 <a name="gst-x-overlay-set-window-handle"></a><h3>gst_x_overlay_set_window_handle ()</h3>
 714 <pre class="programlisting"><span class="returnvalue">void</span>                gst_x_overlay_set_window_handle     (<em class="parameter"><code><a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> *overlay</code></em>,
 715                                                          <em class="parameter"><code><span class="type">guintptr</span> handle</code></em>);</pre>
 716 <p>
 717 This will call the video overlay's set_window_handle method. You
 718 should use this method to tell to a XOverlay to display video output to a
 719 specific window (e.g. an XWindow on X11). Passing 0 as the  <em class="parameter"><code>handle</code></em> will
 720 tell the overlay to stop using that window and create an internal one.
 721 </p>
 722 <div class="variablelist"><table border="0">
 723 <col align="left" valign="top">
 724 <tbody>
 725 <tr>
 726 <td><p><span class="term"><em class="parameter"><code>overlay</code></em> :</span></p></td>
 727 <td>a <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> to set the window on.</td>
 728 </tr>
 729 <tr>
 730 <td><p><span class="term"><em class="parameter"><code>handle</code></em> :</span></p></td>
 731 <td>a handle referencing the window.</td>
 732 </tr>
 733 </tbody>
 734 </table></div>
 735 <p class="since">Since 0.10.31</p>
 736 </div>
 737 <hr>
 738 <div class="refsect2">
 739 <a name="gst-x-overlay-prepare-xwindow-id"></a><h3>gst_x_overlay_prepare_xwindow_id ()</h3>
 740 <pre class="programlisting"><span class="returnvalue">void</span>                gst_x_overlay_prepare_xwindow_id    (<em class="parameter"><code><a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> *overlay</code></em>);</pre>
 741 <p>
 742 This will post a "prepare-xwindow-id" element message on the bus
 743 to give applications an opportunity to call
 744 <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#gst-x-overlay-set-xwindow-id" title="gst_x_overlay_set_xwindow_id ()"><code class="function">gst_x_overlay_set_xwindow_id()</code></a> before a plugin creates its own
 745 window.
 746 </p>
 747 <p>
 748 This function should only be used by video overlay plugin developers.
 749 </p>
 750 <div class="variablelist"><table border="0">
 751 <col align="left" valign="top">
 752 <tbody><tr>
 753 <td><p><span class="term"><em class="parameter"><code>overlay</code></em> :</span></p></td>
 754 <td>a <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> which does not yet have an XWindow.</td>
 755 </tr></tbody>
 756 </table></div>
 757 </div>
 758 <hr>
 759 <div class="refsect2">
 760 <a name="gst-x-overlay-expose"></a><h3>gst_x_overlay_expose ()</h3>
 761 <pre class="programlisting"><span class="returnvalue">void</span>                gst_x_overlay_expose                (<em class="parameter"><code><a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> *overlay</code></em>);</pre>
 762 <p>
 763 Tell an overlay that it has been exposed. This will redraw the current frame
 764 in the drawable even if the pipeline is PAUSED.
 765 </p>
 766 <div class="variablelist"><table border="0">
 767 <col align="left" valign="top">
 768 <tbody><tr>
 769 <td><p><span class="term"><em class="parameter"><code>overlay</code></em> :</span></p></td>
 770 <td>a <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> to expose.</td>
 771 </tr></tbody>
 772 </table></div>
 773 </div>
 774 <hr>
 775 <div class="refsect2">
 776 <a name="gst-x-overlay-handle-events"></a><h3>gst_x_overlay_handle_events ()</h3>
 777 <pre class="programlisting"><span class="returnvalue">void</span>                gst_x_overlay_handle_events         (<em class="parameter"><code><a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> *overlay</code></em>,
 778                                                          <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> handle_events</code></em>);</pre>
 779 <p>
 780 Tell an overlay that it should handle events from the window system. These
 781 events are forwarded upstream as navigation events. In some window system,
 782 events are not propagated in the window hierarchy if a client is listening
 783 for them. This method allows you to disable events handling completely
 784 from the XOverlay.
 785 </p>
 786 <div class="variablelist"><table border="0">
 787 <col align="left" valign="top">
 788 <tbody>
 789 <tr>
 790 <td><p><span class="term"><em class="parameter"><code>overlay</code></em> :</span></p></td>
 791 <td>a <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> to expose.</td>
 792 </tr>
 793 <tr>
 794 <td><p><span class="term"><em class="parameter"><code>handle_events</code></em> :</span></p></td>
 795 <td>a <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> indicating if events should be handled or not.</td>
 796 </tr>
 797 </tbody>
 798 </table></div>
 799 <p class="since">Since 0.10.12</p>
 800 </div>
 801 <hr>
 802 <div class="refsect2">
 803 <a name="gst-x-overlay-set-render-rectangle"></a><h3>gst_x_overlay_set_render_rectangle ()</h3>
 804 <pre class="programlisting"><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>            gst_x_overlay_set_render_rectangle  (<em class="parameter"><code><a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a> *overlay</code></em>,
 805                                                          <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gint"><span class="type">gint</span></a> x</code></em>,
 806                                                          <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gint"><span class="type">gint</span></a> y</code></em>,
 807                                                          <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gint"><span class="type">gint</span></a> width</code></em>,
 808                                                          <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gint"><span class="type">gint</span></a> height</code></em>);</pre>
 809 <p>
 810 Configure a subregion as a video target within the window set by
 811 <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#gst-x-overlay-set-window-handle" title="gst_x_overlay_set_window_handle ()"><code class="function">gst_x_overlay_set_window_handle()</code></a>. If this is not used or not supported
 812 the video will fill the area of the window set as the overlay to 100%.
 813 By specifying the rectangle, the video can be overlayed to a specific region
 814 of that window only. After setting the new rectangle one should call
 815 <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#gst-x-overlay-expose" title="gst_x_overlay_expose ()"><code class="function">gst_x_overlay_expose()</code></a> to force a redraw. To unset the region pass -1 for
 816 the <em class="parameter"><code>width</code></em> and <em class="parameter"><code>height</code></em> parameters.
 817 </p>
 818 <p>
 819 This method is needed for non fullscreen video overlay in UI toolkits that
 820 do not support subwindows.
 821 </p>
 822 <div class="variablelist"><table border="0">
 823 <col align="left" valign="top">
 824 <tbody>
 825 <tr>
 826 <td><p><span class="term"><em class="parameter"><code>overlay</code></em> :</span></p></td>
 827 <td>a <a class="link" href="gst-plugins-base-libs-gstxoverlay.html#GstXOverlay"><span class="type">GstXOverlay</span></a>
 828 </td>
 829 </tr>
 830 <tr>
 831 <td><p><span class="term"><em class="parameter"><code>x</code></em> :</span></p></td>
 832 <td>the horizontal offset of the render area inside the window</td>
 833 </tr>
 834 <tr>
 835 <td><p><span class="term"><em class="parameter"><code>y</code></em> :</span></p></td>
 836 <td>the vertical offset of the render area inside the window</td>
 837 </tr>
 838 <tr>
 839 <td><p><span class="term"><em class="parameter"><code>width</code></em> :</span></p></td>
 840 <td>the width of the render area inside the window</td>
 841 </tr>
 842 <tr>
 843 <td><p><span class="term"><em class="parameter"><code>height</code></em> :</span></p></td>
 844 <td>the height of the render area inside the window</td>
 845 </tr>
 846 <tr>
 847 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 848 <td>
 849 <a href="http://library.gnome.org/devel/glib/unstable/glib-Standard-Macros.html#FALSE:CAPS"><code class="literal">FALSE</code></a> if not supported by the sink.</td>
 850 </tr>
 851 </tbody>
 852 </table></div>
 853 <p class="since">Since 0.10.29</p>
 854 </div>
 855 </div>
 856 </div>
 857 <div class="footer">
 858 <hr>
 859           Generated by GTK-Doc V1.18</div>
 860 </body>
 861 </html>