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| <div class="refentry"> |
| <a name="gst-plugins-base-plugins-videorate"></a><div class="titlepage"></div> |
| <div class="refnamediv"><table width="100%"><tr> |
| <td valign="top"> |
| <h2><span class="refentrytitle"><a name="gst-plugins-base-plugins-videorate.top_of_page"></a>videorate</span></h2> |
| <p>videorate</p> |
| </td> |
| <td class="gallery_image" valign="top" align="right"></td> |
| </tr></table></div> |
| <div class="refsect1"> |
| <a name="gst-plugins-base-plugins-videorate.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/glibglib-Basic-Types.html#guint64"><span class="type">guint64</span></a></td> |
| <td class="property_name"><a class="link" href="gst-plugins-base-plugins-videorate.html#GstVideoRate--average-period" title="The “average-period” property">average-period</a></td> |
| <td class="property_flags">Read / Write</td> |
| </tr> |
| <tr> |
| <td class="property_type"><a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#guint64"><span class="type">guint64</span></a></td> |
| <td class="property_name"><a class="link" href="gst-plugins-base-plugins-videorate.html#GstVideoRate--drop" title="The “drop” property">drop</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-base-plugins-videorate.html#GstVideoRate--drop-only" title="The “drop-only” property">drop-only</a></td> |
| <td class="property_flags">Read / Write</td> |
| </tr> |
| <tr> |
| <td class="property_type"><a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#guint64"><span class="type">guint64</span></a></td> |
| <td class="property_name"><a class="link" href="gst-plugins-base-plugins-videorate.html#GstVideoRate--duplicate" title="The “duplicate” property">duplicate</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#guint64"><span class="type">guint64</span></a></td> |
| <td class="property_name"><a class="link" href="gst-plugins-base-plugins-videorate.html#GstVideoRate--in" title="The “in” property">in</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#gint"><span class="type">gint</span></a></td> |
| <td class="property_name"><a class="link" href="gst-plugins-base-plugins-videorate.html#GstVideoRate--max-rate" title="The “max-rate” property">max-rate</a></td> |
| <td class="property_flags">Read / Write / Construct</td> |
| </tr> |
| <tr> |
| <td class="property_type"><a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gdouble"><span class="type">gdouble</span></a></td> |
| <td class="property_name"><a class="link" href="gst-plugins-base-plugins-videorate.html#GstVideoRate--new-pref" title="The “new-pref” property">new-pref</a></td> |
| <td class="property_flags">Read / Write</td> |
| </tr> |
| <tr> |
| <td class="property_type"><a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#guint64"><span class="type">guint64</span></a></td> |
| <td class="property_name"><a class="link" href="gst-plugins-base-plugins-videorate.html#GstVideoRate--out" title="The “out” property">out</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-base-plugins-videorate.html#GstVideoRate--silent" title="The “silent” property">silent</a></td> |
| <td class="property_flags">Read / Write</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-base-plugins-videorate.html#GstVideoRate--skip-to-first" title="The “skip-to-first” property">skip-to-first</a></td> |
| <td class="property_flags">Read / Write</td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <a name="GstVideoRate"></a><div class="refsect1"> |
| <a name="gst-plugins-base-plugins-videorate.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-base-plugins-videorate.html#GstVideoRate-struct" title="struct GstVideoRate">GstVideoRate</a></td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <div class="refsect1"> |
| <a name="gst-plugins-base-plugins-videorate.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-1.0GstBaseTransform.html#GstBaseTransform-struct">GstBaseTransform</a> |
| <span class="lineart">╰──</span> GstVideoRate |
| </pre> |
| </div> |
| <div class="refsect1"> |
| <a name="gst-plugins-base-plugins-videorate.description"></a><h2>Description</h2> |
| <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 <a class="link" href="gst-plugins-base-plugins-videorate.html#GstVideoRate--in" title="The “in” property"><span class="type">“in”</span></a>, <a class="link" href="gst-plugins-base-plugins-videorate.html#GstVideoRate--out" title="The “out” property"><span class="type">“out”</span></a>, <a class="link" href="gst-plugins-base-plugins-videorate.html#GstVideoRate--duplicate" title="The “duplicate” property"><span class="type">“duplicate”</span></a> |
| and <a class="link" href="gst-plugins-base-plugins-videorate.html#GstVideoRate--drop" title="The “drop” property"><span class="type">“drop”</span></a> 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 <a class="link" href="gst-plugins-base-plugins-videorate.html#GstVideoRate--silent" title="The “silent” property"><span class="type">“silent”</span></a> property is set to FALSE, a GObject property |
| notification will be emitted whenever one of the <a class="link" href="gst-plugins-base-plugins-videorate.html#GstVideoRate--duplicate" title="The “duplicate” property"><span class="type">“duplicate”</span></a> or |
| <a class="link" href="gst-plugins-base-plugins-videorate.html#GstVideoRate--drop" title="The “drop” property"><span class="type">“drop”</span></a> 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> |
| <div class="refsect2"> |
| <a name="id-1.2.54.7.10"></a><h3>Example pipelines</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>v uridecodebin uri<span class="gtkdoc opt">=</span>file<span class="gtkdoc opt">:</span><span class="gtkdoc slc">///path/to/video.ogg ! videoconvert ! videoscale ! videorate ! video/x-raw,framerate=15/1 ! autovideosink</span></pre></td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| Decode a video file and adjust the framerate to 15 fps before playing. |
| To create a test Ogg/Theora file refer to the documentation of theoraenc. |
| <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>v v4l2src <span class="gtkdoc opt">!</span> videorate <span class="gtkdoc opt">!</span> video<span class="gtkdoc opt">/</span>x<span class="gtkdoc opt">-</span>raw<span class="gtkdoc opt">,</span>framerate<span class="gtkdoc opt">=</span><span class="number">25</span><span class="gtkdoc opt">/</span><span class="number">2</span> <span class="gtkdoc opt">!</span> theoraenc <span class="gtkdoc opt">!</span> oggmux <span class="gtkdoc opt">!</span> filesink location<span class="gtkdoc opt">=</span>recording<span class="gtkdoc opt">.</span>ogg</pre></td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| Capture video from a V4L device, and adjust the stream to 12.5 fps before |
| encoding to Ogg/Theora. |
| <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>v uridecodebin uri<span class="gtkdoc opt">=</span>file<span class="gtkdoc opt">:</span><span class="gtkdoc slc">///path/to/video.ogg ! videoconvert ! videoscale ! videorate ! video/x-raw,framerate=1/5 ! jpegenc ! multifilesink location=snapshot-%05d.jpg</span></pre></td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| Decode a video file and save a snapshot every 5 seconds as consecutively numbered jpeg file. |
| </div> |
| <div class="refsynopsisdiv"> |
| <h2>Synopsis</h2> |
| <div class="refsect2"> |
| <a name="id-1.2.54.7.11.1"></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-base-plugins-plugin-videorate.html#plugin-videorate">videorate</a> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term">author</span></p></td> |
| <td>Wim Taymans <wim@fluendo.com></td> |
| </tr> |
| <tr> |
| <td><p><span class="term">class</span></p></td> |
| <td>Filter/Effect/Video</td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="id-1.2.54.7.11.2"></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(ANY)</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"></span></p></td> |
| <td> video/x-bayer(ANY)</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"></span></p></td> |
| <td> image/jpeg(ANY)</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"></span></p></td> |
| <td> image/png(ANY)</td> |
| </tr> |
| </tbody> |
| </table></div> |
| <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>src</td> |
| </tr> |
| <tr> |
| <td><p><span class="term">direction</span></p></td> |
| <td>source</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(ANY)</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"></span></p></td> |
| <td> video/x-bayer(ANY)</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"></span></p></td> |
| <td> image/jpeg(ANY)</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"></span></p></td> |
| <td> image/png(ANY)</td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| </div> |
| </div> |
| <div class="refsect1"> |
| <a name="gst-plugins-base-plugins-videorate.functions_details"></a><h2>Functions</h2> |
| <p></p> |
| </div> |
| <div class="refsect1"> |
| <a name="gst-plugins-base-plugins-videorate.other_details"></a><h2>Types and Values</h2> |
| <div class="refsect2"> |
| <a name="GstVideoRate-struct"></a><h3>struct GstVideoRate</h3> |
| <pre class="programlisting">struct GstVideoRate;</pre> |
| <p>Opaque data structure.</p> |
| </div> |
| </div> |
| <div class="refsect1"> |
| <a name="gst-plugins-base-plugins-videorate.property-details"></a><h2>Property Details</h2> |
| <div class="refsect2"> |
| <a name="GstVideoRate--average-period"></a><h3>The <code class="literal">“average-period”</code> property</h3> |
| <pre class="programlisting"> “average-period” <a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#guint64"><span class="type">guint64</span></a></pre> |
| <p>Arrange for maximum framerate by dropping frames beyond a certain framerate, |
| where the framerate is calculated using a moving average over the |
| configured.</p> |
| <p>Flags: Read / Write</p> |
| <p>Allowed values: <= G_MAXLONG</p> |
| <p>Default value: 0</p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstVideoRate--drop"></a><h3>The <code class="literal">“drop”</code> property</h3> |
| <pre class="programlisting"> “drop” <a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#guint64"><span class="type">guint64</span></a></pre> |
| <p>Number of dropped frames.</p> |
| <p>Flags: Read</p> |
| <p>Default value: 0</p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstVideoRate--drop-only"></a><h3>The <code class="literal">“drop-only”</code> property</h3> |
| <pre class="programlisting"> “drop-only” <a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></pre> |
| <p>Only drop frames, no duplicates are produced.</p> |
| <p>Flags: Read / Write</p> |
| <p>Default value: FALSE</p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstVideoRate--duplicate"></a><h3>The <code class="literal">“duplicate”</code> property</h3> |
| <pre class="programlisting"> “duplicate” <a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#guint64"><span class="type">guint64</span></a></pre> |
| <p>Number of duplicated frames.</p> |
| <p>Flags: Read</p> |
| <p>Default value: 0</p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstVideoRate--in"></a><h3>The <code class="literal">“in”</code> property</h3> |
| <pre class="programlisting"> “in” <a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#guint64"><span class="type">guint64</span></a></pre> |
| <p>Number of input frames.</p> |
| <p>Flags: Read</p> |
| <p>Default value: 0</p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstVideoRate--max-rate"></a><h3>The <code class="literal">“max-rate”</code> property</h3> |
| <pre class="programlisting"> “max-rate” <a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gint"><span class="type">gint</span></a></pre> |
| <p>maximum framerate to pass through</p> |
| <p>Flags: Read / Write / Construct</p> |
| <p>Allowed values: >= 1</p> |
| <p>Default value: 2147483647</p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstVideoRate--new-pref"></a><h3>The <code class="literal">“new-pref”</code> property</h3> |
| <pre class="programlisting"> “new-pref” <a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gdouble"><span class="type">gdouble</span></a></pre> |
| <p>Value indicating how much to prefer new frames (unused).</p> |
| <p>Flags: Read / Write</p> |
| <p>Allowed values: [0,1]</p> |
| <p>Default value: 1</p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstVideoRate--out"></a><h3>The <code class="literal">“out”</code> property</h3> |
| <pre class="programlisting"> “out” <a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#guint64"><span class="type">guint64</span></a></pre> |
| <p>Number of output frames.</p> |
| <p>Flags: Read</p> |
| <p>Default value: 0</p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstVideoRate--silent"></a><h3>The <code class="literal">“silent”</code> property</h3> |
| <pre class="programlisting"> “silent” <a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></pre> |
| <p>Don't emit notify for dropped and duplicated frames.</p> |
| <p>Flags: Read / Write</p> |
| <p>Default value: TRUE</p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstVideoRate--skip-to-first"></a><h3>The <code class="literal">“skip-to-first”</code> property</h3> |
| <pre class="programlisting"> “skip-to-first” <a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></pre> |
| <p>Don't produce buffers before the first one we receive.</p> |
| <p>Flags: Read / Write</p> |
| <p>Default value: FALSE</p> |
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| </div> |
| </div> |
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