1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> 2<html> 3<head> 4<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 5<title>gdkpixbufsink: GStreamer Good Plugins 1.0 Plugins Reference Manual</title> 6<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 7<link rel="home" href="index.html" title="GStreamer Good Plugins 1.0 Plugins Reference Manual"> 8<link rel="up" href="ch01.html" title="gst-plugins-good Elements"> 9<link rel="prev" href="gst-plugins-good-plugins-gdkpixbufoverlay.html" title="gdkpixbufoverlay"> 10<link rel="next" href="gst-plugins-good-plugins-goom2k1.html" title="goom2k1"> 11<meta name="generator" content="GTK-Doc V1.28 (XML mode)"> 12<link rel="stylesheet" href="style.css" type="text/css"> 13</head> 14<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 15<table class="navigation" id="top" width="100%" summary="Navigation header" cellpadding="2" cellspacing="5"><tr valign="middle"> 16<td 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href="gst-plugins-good-plugins-goom2k1.html"><img src="right.png" width="16" height="16" border="0" alt="Next"></a></td> 26</tr></table> 27<div class="refentry"> 28<a name="gst-plugins-good-plugins-gdkpixbufsink"></a><div class="titlepage"></div> 29<div class="refnamediv"><table width="100%"><tr> 30<td valign="top"> 31<h2><span class="refentrytitle"><a name="gst-plugins-good-plugins-gdkpixbufsink.top_of_page"></a>gdkpixbufsink</span></h2> 32<p>gdkpixbufsink</p> 33</td> 34<td class="gallery_image" valign="top" align="right"></td> 35</tr></table></div> 36<div class="refsect1"> 37<a name="gst-plugins-good-plugins-gdkpixbufsink.properties"></a><h2>Properties</h2> 38<div class="informaltable"><table class="informaltable" border="0"> 39<colgroup> 40<col width="150px" class="properties_type"> 41<col width="300px" class="properties_name"> 42<col width="200px" class="properties_flags"> 43</colgroup> 44<tbody> 45<tr> 46<td class="property_type"> 47<a href="/usr/share/gtk-doc/html/gdk-pixbuf/gdk-pixbuf-The-GdkPixbuf-Structure.html#GdkPixbuf-struct"><span class="type">GdkPixbuf</span></a> *</td> 48<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> 49<td class="property_flags">Read</td> 50</tr> 51<tr> 52<td class="property_type"><a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></td> 53<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> 54<td class="property_flags">Read / Write</td> 55</tr> 56</tbody> 57</table></div> 58</div> 59<a name="GstGdkPixbufSink"></a><div class="refsect1"> 60<a name="gst-plugins-good-plugins-gdkpixbufsink.other"></a><h2>Types and Values</h2> 61<div class="informaltable"><table class="informaltable" width="100%" border="0"> 62<colgroup> 63<col width="150px" class="name"> 64<col class="description"> 65</colgroup> 66<tbody><tr> 67<td class="datatype_keyword">struct</td> 68<td class="function_name"><a class="link" href="gst-plugins-good-plugins-gdkpixbufsink.html#GstGdkPixbufSink-struct" title="struct GstGdkPixbufSink">GstGdkPixbufSink</a></td> 69</tr></tbody> 70</table></div> 71</div> 72<div class="refsect1"> 73<a name="gst-plugins-good-plugins-gdkpixbufsink.object-hierarchy"></a><h2>Object Hierarchy</h2> 74<pre class="screen"> <a href="/usr/share/gtk-doc/html/gobject/gobject-The-Base-Object-Type.html#GObject-struct">GObject</a> 75 <span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gobject/gobject-The-Base-Object-Type.html#GInitiallyUnowned">GInitiallyUnowned</a> 76 <span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gstreamer-1.0/GstObject.html#GstObject-struct">GstObject</a> 77 <span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gstreamer-1.0/GstElement.html#GstElement-struct">GstElement</a> 78 <span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gstreamer-libs-1.0/GstBaseSink.html#GstBaseSink-struct">GstBaseSink</a> 79 <span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gst-plugins-base-libs-1.0/GstVideoSink.html#GstVideoSink-struct">GstVideoSink</a> 80 <span class="lineart">╰──</span> GstGdkPixbufSink 81</pre> 82</div> 83<div class="refsect1"> 84<a name="gst-plugins-good-plugins-gdkpixbufsink.description"></a><h2>Description</h2> 85<p>This sink element takes RGB or RGBA images as input and wraps them into 86<a href="/usr/share/gtk-doc/html/gdk-pixbuf/gdk-pixbuf-The-GdkPixbuf-Structure.html#GdkPixbuf-struct"><span class="type">GdkPixbuf</span></a> objects, for easy saving to file via the 87GdkPixbuf library API or displaying in Gtk+ applications (e.g. using 88the <a href="/usr/share/gtk-doc/html/gtk3/GtkImage.html#GtkImage-struct"><span class="type">GtkImage</span></a> widget).</p> 89<p>There are two ways to use this element and obtain the <a href="/usr/share/gtk-doc/html/gdk-pixbuf/gdk-pixbuf-The-GdkPixbuf-Structure.html#GdkPixbuf-struct"><span class="type">GdkPixbuf</span></a> objects 90created:</p> 91<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 92<li class="listitem"> 93Watching for element messages named <code class="classname">"preroll-pixbuf" 94</code> or <code class="classname">"pixbuf"</code> on the bus, which 95will be posted whenever an image would usually be rendered. See below for 96more details on these messages and how to extract the pixbuf object 97contained in them. 98</li> 99<li class="listitem"> 100Retrieving 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 101when needed. This is the easiest way to get at pixbufs for snapshotting 102purposes - just wait until the pipeline is prerolled (ASYNC_DONE message 103on the bus), then read the property. If you use this method, you may want 104to 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> 105property to <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#FALSE:CAPS"><code class="literal">FALSE</code></a>. This avoids unnecessary memory overhead. 106</li> 107</ul></div> 108<p>The primary purpose of this element is to abstract away the <a href="/usr/share/gtk-doc/html/gstreamer-1.0/GstBuffer.html#GstBuffer-struct"><span class="type">GstBuffer</span></a> to 109<a href="/usr/share/gtk-doc/html/gdk-pixbuf/gdk-pixbuf-The-GdkPixbuf-Structure.html#GdkPixbuf-struct"><span class="type">GdkPixbuf</span></a> conversion. Other than that it's very similar to the fakesink 110element.</p> 111<p>This element is meant for easy no-hassle video snapshotting. It is not 112suitable for video playback or video display at high framerates. Use 113ximagesink, xvimagesink or some other suitable video sink in connection 114with the <span class="type">GstXOverlay</span> interface instead if you want to do video playback.</p> 115<div class="refsect2"> 116<a name="id-1.2.67.7.7"></a><h3>Message details</h3> 117As mentioned above, this element will by default post element messages 118containing structures named <code class="classname">"preroll-pixbuf" 119</code> or <code class="classname">"pixbuf"</code> on the bus (this 120can 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 121to <a href="/usr/share/gtk-doc/html/glib/glib-Standard-Macros.html#FALSE:CAPS"><code class="literal">FALSE</code></a> though). The element message structure has the following fields: 122<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 123<li class="listitem"> 124<code class="classname">"pixbuf"</code>: the <a href="/usr/share/gtk-doc/html/gdk-pixbuf/gdk-pixbuf-The-GdkPixbuf-Structure.html#GdkPixbuf-struct"><span class="type">GdkPixbuf</span></a> object 125</li> 126<li class="listitem"> 127<code class="classname">"pixel-aspect-ratio"</code>: the pixel aspect 128 ratio (PAR) of the input image (this field contains a <span class="type">GstFraction</span>); the 129 PAR is usually 1:1 for images, but is often something non-1:1 in the case 130 of video input. In this case the image may be distorted and you may need 131 to rescale it accordingly before saving it to file or displaying it. This 132 can easily be done using <a href="/usr/share/gtk-doc/html/gdk-pixbuf/gdk-pixbuf-Scaling.html#gdk-pixbuf-scale"><code class="function">gdk_pixbuf_scale()</code></a> (the reason this is not done 133 automatically is that the application will often scale the image anyway 134 according to the size of the output window, in which case it is much more 135 efficient to only scale once rather than twice). You can put a videoscale 136 element and a capsfilter element with 137 <code class="literal">video/x-raw-rgb,pixel-aspect-ratio=(fraction)1/1</code> caps 138 in front of this element to make sure the pixbufs always have a 1:1 PAR. 139</li> 140</ul></div> 141</div> 142<hr> 143<div class="refsect2"> 144<a name="id-1.2.67.7.8"></a><h3>Example pipeline</h3> 145<div class="informalexample"> 146 <table class="listing_frame" border="0" cellpadding="0" cellspacing="0"> 147 <tbody> 148 <tr> 149 <td class="listing_lines" align="right"><pre>1</pre></td> 150 <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> 151 </tr> 152 </tbody> 153 </table> 154</div> 155 Process one single test image as pixbuf (note that the output you see will 156be slightly misleading. The message structure does contain a valid pixbuf 157object even if the structure string says '(NULL)'). 158</div> 159<div class="refsynopsisdiv"> 160<h2>Synopsis</h2> 161<div class="refsect2"> 162<a name="id-1.2.67.7.9.1"></a><h3>Element Information</h3> 163<div class="variablelist"><table border="0" class="variablelist"> 164<colgroup> 165<col align="left" valign="top"> 166<col> 167</colgroup> 168<tbody> 169<tr> 170<td><p><span class="term">plugin</span></p></td> 171<td> 172 <a class="link" href="gst-plugins-good-plugins-plugin-gdkpixbuf.html#plugin-gdkpixbuf">gdkpixbuf</a> 173 </td> 174</tr> 175<tr> 176<td><p><span class="term">author</span></p></td> 177<td>Tim-Philipp Müller <tim centricular net></td> 178</tr> 179<tr> 180<td><p><span class="term">class</span></p></td> 181<td>Sink/Video</td> 182</tr> 183</tbody> 184</table></div> 185</div> 186<hr> 187<div class="refsect2"> 188<a name="id-1.2.67.7.9.2"></a><h3>Element Pads</h3> 189<div class="variablelist"><table border="0" class="variablelist"> 190<colgroup> 191<col align="left" valign="top"> 192<col> 193</colgroup> 194<tbody> 195<tr> 196<td><p><span class="term">name</span></p></td> 197<td>sink</td> 198</tr> 199<tr> 200<td><p><span class="term">direction</span></p></td> 201<td>sink</td> 202</tr> 203<tr> 204<td><p><span class="term">presence</span></p></td> 205<td>always</td> 206</tr> 207<tr> 208<td><p><span class="term">details</span></p></td> 209<td>video/x-raw, format=(string)RGB, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]</td> 210</tr> 211<tr> 212<td><p><span class="term"></span></p></td> 213<td> video/x-raw, format=(string)RGBA, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]</td> 214</tr> 215</tbody> 216</table></div> 217</div> 218</div> 219</div> 220<div class="refsect1"> 221<a name="gst-plugins-good-plugins-gdkpixbufsink.functions_details"></a><h2>Functions</h2> 222<p></p> 223</div> 224<div class="refsect1"> 225<a name="gst-plugins-good-plugins-gdkpixbufsink.other_details"></a><h2>Types and Values</h2> 226<div class="refsect2"> 227<a name="GstGdkPixbufSink-struct"></a><h3>struct GstGdkPixbufSink</h3> 228<pre class="programlisting">struct GstGdkPixbufSink;</pre> 229<p>Opaque element structure.</p> 230</div> 231</div> 232<div class="refsect1"> 233<a name="gst-plugins-good-plugins-gdkpixbufsink.property-details"></a><h2>Property Details</h2> 234<div class="refsect2"> 235<a name="GstGdkPixbufSink--last-pixbuf"></a><h3>The <code class="literal">“last-pixbuf”</code> property</h3> 236<pre class="programlisting"> “last-pixbuf” <a href="/usr/share/gtk-doc/html/gdk-pixbuf/gdk-pixbuf-The-GdkPixbuf-Structure.html#GdkPixbuf-struct"><span class="type">GdkPixbuf</span></a> *</pre> 237<p>Last GdkPixbuf object rendered.</p> 238<p>Flags: Read</p> 239</div> 240<hr> 241<div class="refsect2"> 242<a name="GstGdkPixbufSink--post-messages"></a><h3>The <code class="literal">“post-messages”</code> property</h3> 243<pre class="programlisting"> “post-messages” <a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></pre> 244<p>Whether to post messages containing pixbufs on the bus.</p> 245<p>Flags: Read / Write</p> 246<p>Default value: TRUE</p> 247</div> 248</div> 249</div> 250<div class="footer"> 251<hr>Generated by GTK-Doc V1.28</div> 252</body> 253</html>
