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<tr><td colspan="5" class="shortcuts"><nobr><a href="#id2617962" class="shortcut">Top</a>
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<a href="#id2590751" class="shortcut">Description</a>
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<a href="#id2617914" class="shortcut">Object Hierarchy</a>
 | 
<a href="#id2617891" class="shortcut">Properties</a></nobr></td></tr>
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<div class="refentry" lang="en">
<a name="gst-plugins-base-plugins-videorate"></a><div class="titlepage"></div>
<div class="refnamediv"><table width="100%"><tr>
<td valign="top">
<h2>
<a name="id2617962"></a><span class="refentrytitle">videorate</span>
</h2>
<p>videorate — retimestamps and drops/duplicates video frames to
match the source pad's framerate and create a perfect stream</p>
</td>
<td valign="top" align="right"></td>
</tr></table></div>
<div class="refsynopsisdiv">
<h2>Synopsis</h2>
<a name="GstVideoRate"></a><pre class="synopsis">
<a href="gst-plugins-base-plugins-videorate.html#GstVideoRate-struct">GstVideoRate</a>;
</pre>
</div>
<div class="refsect1" lang="en">
<a name="id2617914"></a><h2>Object Hierarchy</h2>
<pre class="synopsis">
GObject
+----GstObject
+----GstElement
+----GstVideoRate
</pre>
</div>
<div class="refsect1" lang="en">
<a name="id2617891"></a><h2>Properties</h2>
<pre class="synopsis">
"<a href="gst-plugins-base-plugins-videorate.html#GstVideoRate--drop">drop</a>" guint64 : Read
"<a href="gst-plugins-base-plugins-videorate.html#GstVideoRate--duplicate">duplicate</a>" guint64 : Read
"<a href="gst-plugins-base-plugins-videorate.html#GstVideoRate--in">in</a>" guint64 : Read
"<a href="gst-plugins-base-plugins-videorate.html#GstVideoRate--new-pref">new-pref</a>" gdouble : Read / Write
"<a href="gst-plugins-base-plugins-videorate.html#GstVideoRate--out">out</a>" guint64 : Read
"<a href="gst-plugins-base-plugins-videorate.html#GstVideoRate--silent">silent</a>" gboolean : Read / Write
</pre>
</div>
<div class="refsect1" lang="en">
<a name="id2590751"></a><h2>Description</h2>
<p>
</p>
<div class="refsect2" lang="en">
<a name="id2585540"></a><p>
This element takes an incoming stream of timestamped video frames.
It will produce a perfect stream that matches the source pad's framerate.
</p>
<p>
The correction is performed by dropping and duplicating frames, no fancy
algorithm is used to interpolate frames (yet).
</p>
<p>
By default the element will simply negotiate the same framerate on its
source and sink pad.
</p>
<p>
This operation is useful to link to elements that require a perfect stream.
Typical examples are formats that do not store timestamps for video frames,
but only store a framerate, like Ogg and AVI.
</p>
<p>
A conversion to a specific framerate can be forced by using filtered caps on
the source pad.
</p>
<p>
The properties "in", "out", "duplicate" and "drop" can be read to obtain
information about number of input frames, output frames, dropped frames
(i.e. the number of unused input frames) and duplicated frames (i.e. the
number of times an input frame was duplicated, beside being used normally).
</p>
<p>
An input stream that needs no adjustments will thus never have dropped or
duplicated frames.
</p>
<p>
When the "silent" property is set to FALSE, a GObject property notification
will be emitted whenever one of the "duplicate" or "drop" values changes.
This can potentially cause performance degradation.
Note that property notification will happen from the streaming thread, so
applications should be prepared for this.
</p>
<h3>Example pipelines</h3>
<p>
</p>
<pre class="programlisting">
gst-launch -v filesrc location=videotestsrc.ogg ! oggdemux ! theoradec ! videorate ! video/x-raw-yuv,framerate=15/1 ! xvimagesink
</pre>
<p>
Decode an Ogg/Theora file and adjust the framerate to 15 fps before playing.
To create the test Ogg/Theora file refer to the documentation of theoraenc.
</p>
<p>
</p>
<pre class="programlisting">
gst-launch -v v4lsrc ! videorate ! video/x-raw-yuv,framerate=25/2 ! theoraenc ! oggmux ! filesink location=v4l.ogg
</pre>
<p>
Capture video from a V4L device, and adjust the stream to 12.5 fps before
encoding to Ogg/Theora.
</p>
</div>
<p>
</p>
<p>
Last reviewed on 2006-09-02 (0.10.11)</p>
<div class="refsect2" lang="en">
<a name="id2617876"></a><h3>Element Information</h3>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><span class="term">plugin</span></td>
<td>
<a href="gst-plugins-base-plugins-plugin-videorate.html#plugin-videorate">videorate</a>
</td>
</tr>
<tr>
<td><span class="term">author</span></td>
<td>Wim Taymans <wim@fluendo.com></td>
</tr>
<tr>
<td><span class="term">class</span></td>
<td>Filter/Effect/Video</td>
</tr>
</tbody>
</table></div>
<h3>Element Pads</h3>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><span class="term">name</span></td>
<td>sink</td>
</tr>
<tr>
<td><span class="term">direction</span></td>
<td>sink</td>
</tr>
<tr>
<td><span class="term">presence</span></td>
<td>always</td>
</tr>
<tr>
<td><span class="term">details</span></td>
<td>video/x-raw-yuv; video/x-raw-rgb</td>
</tr>
</tbody>
</table></div>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><span class="term">name</span></td>
<td>src</td>
</tr>
<tr>
<td><span class="term">direction</span></td>
<td>source</td>
</tr>
<tr>
<td><span class="term">presence</span></td>
<td>always</td>
</tr>
<tr>
<td><span class="term">details</span></td>
<td>video/x-raw-yuv; video/x-raw-rgb</td>
</tr>
</tbody>
</table></div>
</div>
<p>
</p>
</div>
<div class="refsect1" lang="en">
<a name="id2613772"></a><h2>Details</h2>
<div class="refsect2" lang="en">
<a name="id2613783"></a><h3>
<a name="GstVideoRate-struct"></a>GstVideoRate</h3>
<a class="indexterm" name="id2613795"></a><pre class="programlisting">typedef struct _GstVideoRate GstVideoRate;</pre>
<p>
Opaque data structure.</p>
<p>
</p>
</div>
</div>
<div class="refsect1" lang="en">
<a name="id2613816"></a><h2>Property Details</h2>
<div class="refsect2" lang="en">
<a name="id2613826"></a><h3>
<a name="GstVideoRate--drop"></a>The "<code class="literal">drop</code>" property</h3>
<a class="indexterm" name="id2613841"></a><pre class="programlisting"> "drop" guint64 : Read</pre>
<p>Number of dropped frames.</p>
<p>Default value: 0</p>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2615281"></a><h3>
<a name="GstVideoRate--duplicate"></a>The "<code class="literal">duplicate</code>" property</h3>
<a class="indexterm" name="id2615295"></a><pre class="programlisting"> "duplicate" guint64 : Read</pre>
<p>Number of duplicated frames.</p>
<p>Default value: 0</p>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2615320"></a><h3>
<a name="GstVideoRate--in"></a>The "<code class="literal">in</code>" property</h3>
<a class="indexterm" name="id2615335"></a><pre class="programlisting"> "in" guint64 : Read</pre>
<p>Number of input frames.</p>
<p>Default value: 0</p>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2615360"></a><h3>
<a name="GstVideoRate--new-pref"></a>The "<code class="literal">new-pref</code>" property</h3>
<a class="indexterm" name="id2615374"></a><pre class="programlisting"> "new-pref" gdouble : Read / Write</pre>
<p>Value indicating how much to prefer new frames (unused).</p>
<p>Allowed values: [0,1]</p>
<p>Default value: 1</p>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2615405"></a><h3>
<a name="GstVideoRate--out"></a>The "<code class="literal">out</code>" property</h3>
<a class="indexterm" name="id2615420"></a><pre class="programlisting"> "out" guint64 : Read</pre>
<p>Number of output frames.</p>
<p>Default value: 0</p>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2615445"></a><h3>
<a name="GstVideoRate--silent"></a>The "<code class="literal">silent</code>" property</h3>
<a class="indexterm" name="id2615459"></a><pre class="programlisting"> "silent" gboolean : Read / Write</pre>
<p>Don't emit notify for dropped and duplicated frames.</p>
<p>Default value: TRUE</p>
</div>
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