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<div class="refentry">
<a name="gst-plugins-good-plugins-gdkpixbufsink"></a><div class="titlepage"></div>
<div class="refnamediv"><table width="100%"><tr>
<td valign="top">
<h2><span class="refentrytitle"><a name="gst-plugins-good-plugins-gdkpixbufsink.top_of_page"></a>gdkpixbufsink</span></h2>
<p>gdkpixbufsink</p>
</td>
<td class="gallery_image" valign="top" align="right"></td>
</tr></table></div>
<div class="refsect1">
<a name="gst-plugins-good-plugins-gdkpixbufsink.properties"></a><h2>Properties</h2>
<div class="informaltable"><table class="informaltable" border="0">
<colgroup>
<col width="150px" class="properties_type">
<col width="300px" class="properties_name">
<col width="200px" class="properties_flags">
</colgroup>
<tbody>
<tr>
<td class="property_type">
<a href="/usr/share/gtk-doc/html/gdk-pixbufgdk-pixbuf-The-GdkPixbuf-Structure.html#GdkPixbuf-struct"><span class="type">GdkPixbuf</span></a> *</td>
<td class="property_name"><a class="link" href="gst-plugins-good-plugins-gdkpixbufsink.html#GstGdkPixbufSink--last-pixbuf" title="The “last-pixbuf” property">last-pixbuf</a></td>
<td class="property_flags">Read</td>
</tr>
<tr>
<td class="property_type"><a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></td>
<td class="property_name"><a class="link" href="gst-plugins-good-plugins-gdkpixbufsink.html#GstGdkPixbufSink--post-messages" title="The “post-messages” property">post-messages</a></td>
<td class="property_flags">Read / Write</td>
</tr>
</tbody>
</table></div>
</div>
<a name="GstGdkPixbufSink"></a><div class="refsect1">
<a name="gst-plugins-good-plugins-gdkpixbufsink.other"></a><h2>Types and Values</h2>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="name">
<col class="description">
</colgroup>
<tbody><tr>
<td class="datatype_keyword">struct</td>
<td class="function_name"><a class="link" href="gst-plugins-good-plugins-gdkpixbufsink.html#GstGdkPixbufSink-struct" title="struct GstGdkPixbufSink">GstGdkPixbufSink</a></td>
</tr></tbody>
</table></div>
</div>
<div class="refsect1">
<a name="gst-plugins-good-plugins-gdkpixbufsink.object-hierarchy"></a><h2>Object Hierarchy</h2>
<pre class="screen"> <a href="/usr/share/gtk-doc/html/gobjectgobject-The-Base-Object-Type.html#GObject-struct">GObject</a>
<span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gobjectgobject-The-Base-Object-Type.html#GInitiallyUnowned">GInitiallyUnowned</a>
<span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gstreamer-1.0GstObject.html#GstObject-struct">GstObject</a>
<span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gstreamer-1.0GstElement.html#GstElement-struct">GstElement</a>
<span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gstreamer-libs-1.0GstBaseSink.html#GstBaseSink-struct">GstBaseSink</a>
<span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gst-plugins-base-libs-1.0gst-plugins-base-libs-gstvideosink.html#GstVideoSink-struct">GstVideoSink</a>
<span class="lineart">╰──</span> GstGdkPixbufSink
</pre>
</div>
<div class="refsect1">
<a name="gst-plugins-good-plugins-gdkpixbufsink.description"></a><h2>Description</h2>
<p>This sink element takes RGB or RGBA images as input and wraps them into
<a href="/usr/share/gtk-doc/html/gdk-pixbufgdk-pixbuf-The-GdkPixbuf-Structure.html#GdkPixbuf-struct"><span class="type">GdkPixbuf</span></a> objects, for easy saving to file via the
GdkPixbuf library API or displaying in Gtk+ applications (e.g. using
the <a href="/usr/share/gtk-doc/html/gtk3GtkImage.html#GtkImage-struct"><span class="type">GtkImage</span></a> widget).</p>
<p>There are two ways to use this element and obtain the <a href="/usr/share/gtk-doc/html/gdk-pixbufgdk-pixbuf-The-GdkPixbuf-Structure.html#GdkPixbuf-struct"><span class="type">GdkPixbuf</span></a> objects
created:</p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
Watching for element messages named <code class="classname">"preroll-pixbuf"
</code> or <code class="classname">"pixbuf"</code> on the bus, which
will be posted whenever an image would usually be rendered. See below for
more details on these messages and how to extract the pixbuf object
contained in them.
</li>
<li class="listitem">
Retrieving the current pixbuf via the <a class="link" href="gst-plugins-good-plugins-gdkpixbufsink.html#GstGdkPixbufSink--last-pixbuf" title="The “last-pixbuf” property"><span class="type">“last-pixbuf”</span></a> property
when needed. This is the easiest way to get at pixbufs for snapshotting
purposes - just wait until the pipeline is prerolled (ASYNC_DONE message
on the bus), then read the property. If you use this method, you may want
to disable message posting by setting the <a class="link" href="gst-plugins-good-plugins-gdkpixbufsink.html#GstGdkPixbufSink--post-messages" title="The “post-messages” property"><span class="type">“post-messages”</span></a>
property to <a href="/usr/share/gtk-doc/html/glibglib-Standard-Macros.html#FALSE:CAPS"><span class="type">FALSE</span></a>. This avoids unnecessary memory overhead.
</li>
</ul></div>
<p>The primary purpose of this element is to abstract away the <a href="/usr/share/gtk-doc/html/gstreamer-1.0GstBuffer.html#GstBuffer-struct"><span class="type">GstBuffer</span></a> to
<a href="/usr/share/gtk-doc/html/gdk-pixbufgdk-pixbuf-The-GdkPixbuf-Structure.html#GdkPixbuf-struct"><span class="type">GdkPixbuf</span></a> conversion. Other than that it's very similar to the fakesink
element.</p>
<p>This element is meant for easy no-hassle video snapshotting. It is not
suitable for video playback or video display at high framerates. Use
ximagesink, xvimagesink or some other suitable video sink in connection
with the <span class="type">GstXOverlay</span> interface instead if you want to do video playback.</p>
<div class="refsect2">
<a name="id-1.2.67.7.7"></a><h3>Message details</h3>
As mentioned above, this element will by default post element messages
containing structures named <code class="classname">"preroll-pixbuf"
</code> or <code class="classname">"pixbuf"</code> on the bus (this
can be disabled by setting the <a class="link" href="gst-plugins-good-plugins-gdkpixbufsink.html#GstGdkPixbufSink--post-messages" title="The “post-messages” property"><span class="type">“post-messages”</span></a> property
to <a href="/usr/share/gtk-doc/html/glibglib-Standard-Macros.html#FALSE:CAPS"><span class="type">FALSE</span></a> though). The element message structure has the following fields:
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<code class="classname">"pixbuf"</code>: the <a href="/usr/share/gtk-doc/html/gdk-pixbufgdk-pixbuf-The-GdkPixbuf-Structure.html#GdkPixbuf-struct"><span class="type">GdkPixbuf</span></a> object
</li>
<li class="listitem">
<code class="classname">"pixel-aspect-ratio"</code>: the pixel aspect
ratio (PAR) of the input image (this field contains a <span class="type">GstFraction</span>); the
PAR is usually 1:1 for images, but is often something non-1:1 in the case
of video input. In this case the image may be distorted and you may need
to rescale it accordingly before saving it to file or displaying it. This
can easily be done using <a href="/usr/share/gtk-doc/html/gdk-pixbufgdk-pixbuf-Scaling.html#gdk-pixbuf-scale"><code class="function">gdk_pixbuf_scale()</code></a> (the reason this is not done
automatically is that the application will often scale the image anyway
according to the size of the output window, in which case it is much more
efficient to only scale once rather than twice). You can put a videoscale
element and a capsfilter element with
<code class="literal">video/x-raw-rgb,pixel-aspect-ratio=(fraction)1/1</code> caps
in front of this element to make sure the pixbufs always have a 1:1 PAR.
</li>
</ul></div>
</div>
<hr>
<div class="refsect2">
<a name="id-1.2.67.7.8"></a><h3>Example pipeline</h3>
<div class="informalexample">
<table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
<tbody>
<tr>
<td class="listing_lines" align="right"><pre>1</pre></td>
<td class="listing_code"><pre class="programlisting">gst<span class="gtkdoc opt">-</span>launch<span class="gtkdoc opt">-</span><span class="number">1.0</span> <span class="gtkdoc opt">-</span>m <span class="gtkdoc opt">-</span>v videotestsrc num<span class="gtkdoc opt">-</span>buffers<span class="gtkdoc opt">=</span><span class="number">1</span> <span class="gtkdoc opt">!</span> gdkpixbufsink</pre></td>
</tr>
</tbody>
</table>
</div>
Process one single test image as pixbuf (note that the output you see will
be slightly misleading. The message structure does contain a valid pixbuf
object even if the structure string says '(NULL)').
</div>
<div class="refsynopsisdiv">
<h2>Synopsis</h2>
<div class="refsect2">
<a name="id-1.2.67.7.9.1"></a><h3>Element Information</h3>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term">plugin</span></p></td>
<td>
<a class="link" href="gst-plugins-good-plugins-plugin-gdkpixbuf.html#plugin-gdkpixbuf">gdkpixbuf</a>
</td>
</tr>
<tr>
<td><p><span class="term">author</span></p></td>
<td>Tim-Philipp Müller &lt;tim centricular net&gt;</td>
</tr>
<tr>
<td><p><span class="term">class</span></p></td>
<td>Sink/Video</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="id-1.2.67.7.9.2"></a><h3>Element Pads</h3>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term">name</span></p></td>
<td>sink</td>
</tr>
<tr>
<td><p><span class="term">direction</span></p></td>
<td>sink</td>
</tr>
<tr>
<td><p><span class="term">presence</span></p></td>
<td>always</td>
</tr>
<tr>
<td><p><span class="term">details</span></p></td>
<td>video/x-raw, format=(string)RGB, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]</td>
</tr>
<tr>
<td><p><span class="term"></span></p></td>
<td> video/x-raw, format=(string)RGBA, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]</td>
</tr>
</tbody>
</table></div>
</div>
</div>
</div>
<div class="refsect1">
<a name="gst-plugins-good-plugins-gdkpixbufsink.functions_details"></a><h2>Functions</h2>
<p></p>
</div>
<div class="refsect1">
<a name="gst-plugins-good-plugins-gdkpixbufsink.other_details"></a><h2>Types and Values</h2>
<div class="refsect2">
<a name="GstGdkPixbufSink-struct"></a><h3>struct GstGdkPixbufSink</h3>
<pre class="programlisting">struct GstGdkPixbufSink;</pre>
<p>Opaque element structure.</p>
</div>
</div>
<div class="refsect1">
<a name="gst-plugins-good-plugins-gdkpixbufsink.property-details"></a><h2>Property Details</h2>
<div class="refsect2">
<a name="GstGdkPixbufSink--last-pixbuf"></a><h3>The <code class="literal">“last-pixbuf”</code> property</h3>
<pre class="programlisting"> “last-pixbuf” <a href="/usr/share/gtk-doc/html/gdk-pixbufgdk-pixbuf-The-GdkPixbuf-Structure.html#GdkPixbuf-struct"><span class="type">GdkPixbuf</span></a> *</pre>
<p>Last GdkPixbuf object rendered.</p>
<p>Flags: Read</p>
</div>
<hr>
<div class="refsect2">
<a name="GstGdkPixbufSink--post-messages"></a><h3>The <code class="literal">“post-messages”</code> property</h3>
<pre class="programlisting"> “post-messages” <a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></pre>
<p>Whether to post messages containing pixbufs on the bus.</p>
<p>Flags: Read / Write</p>
<p>Default value: TRUE</p>
</div>
</div>
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