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<a href="#gstreamer-GstSegment.description" class="shortcut">Description</a>
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<h2><span class="refentrytitle"><a name="gstreamer-GstSegment.top_of_page"></a>GstSegment</span></h2>
<p>GstSegment — Structure describing the configured region of interest
in a media file.</p>
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<td valign="top" align="right"></td>
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<div class="refsynopsisdiv">
<a name="gstreamer-GstSegment.synopsis"></a><h2>Synopsis</h2>
<pre class="synopsis">
#include <gst/gst.h>
struct <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment">GstSegment</a>;
enum <a class="link" href="gstreamer-GstSegment.html#GstSegmentFlags" title="enum GstSegmentFlags">GstSegmentFlags</a>;
<a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a> <a class="link" href="gstreamer-GstSegment.html#gst-segment-clip" title="gst_segment_clip ()">gst_segment_clip</a> (<em class="parameter"><code>const <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *segment</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>,
<em class="parameter"><code><span class="type">guint64</span> start</code></em>,
<em class="parameter"><code><span class="type">guint64</span> stop</code></em>,
<em class="parameter"><code><span class="type">guint64</span> *clip_start</code></em>,
<em class="parameter"><code><span class="type">guint64</span> *clip_stop</code></em>);
<span class="returnvalue">void</span> <a class="link" href="gstreamer-GstSegment.html#gst-segment-init" title="gst_segment_init ()">gst_segment_init</a> (<em class="parameter"><code><a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *segment</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>);
<a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="returnvalue">GstSegment</span></a> * <a class="link" href="gstreamer-GstSegment.html#gst-segment-new" title="gst_segment_new ()">gst_segment_new</a> (<em class="parameter"><code><span class="type">void</span></code></em>);
<a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="returnvalue">GstSegment</span></a> * <a class="link" href="gstreamer-GstSegment.html#gst-segment-copy" title="gst_segment_copy ()">gst_segment_copy</a> (<em class="parameter"><code>const <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *segment</code></em>);
<span class="returnvalue">void</span> <a class="link" href="gstreamer-GstSegment.html#gst-segment-free" title="gst_segment_free ()">gst_segment_free</a> (<em class="parameter"><code><a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *segment</code></em>);
<a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a> <a class="link" href="gstreamer-GstSegment.html#gst-segment-do-seek" title="gst_segment_do_seek ()">gst_segment_do_seek</a> (<em class="parameter"><code><a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *segment</code></em>,
<em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gdouble"><span class="type">gdouble</span></a> rate</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstEvent.html#GstSeekFlags" title="enum GstSeekFlags"><span class="type">GstSeekFlags</span></a> flags</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstEvent.html#GstSeekType" title="enum GstSeekType"><span class="type">GstSeekType</span></a> start_type</code></em>,
<em class="parameter"><code><span class="type">guint64</span> start</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstEvent.html#GstSeekType" title="enum GstSeekType"><span class="type">GstSeekType</span></a> stop_type</code></em>,
<em class="parameter"><code><span class="type">guint64</span> stop</code></em>,
<em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> *update</code></em>);
<span class="returnvalue">guint64</span> <a class="link" href="gstreamer-GstSegment.html#gst-segment-to-running-time" title="gst_segment_to_running_time ()">gst_segment_to_running_time</a> (<em class="parameter"><code>const <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *segment</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>,
<em class="parameter"><code><span class="type">guint64</span> position</code></em>);
<span class="returnvalue">guint64</span> <a class="link" href="gstreamer-GstSegment.html#gst-segment-to-stream-time" title="gst_segment_to_stream_time ()">gst_segment_to_stream_time</a> (<em class="parameter"><code>const <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *segment</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>,
<em class="parameter"><code><span class="type">guint64</span> position</code></em>);
<span class="returnvalue">guint64</span> <a class="link" href="gstreamer-GstSegment.html#gst-segment-to-position" title="gst_segment_to_position ()">gst_segment_to_position</a> (<em class="parameter"><code>const <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *segment</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>,
<em class="parameter"><code><span class="type">guint64</span> running_time</code></em>);
<a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a> <a class="link" href="gstreamer-GstSegment.html#gst-segment-set-running-time" title="gst_segment_set_running_time ()">gst_segment_set_running_time</a> (<em class="parameter"><code><a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *segment</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>,
<em class="parameter"><code><span class="type">guint64</span> running_time</code></em>);
<span class="returnvalue">void</span> <a class="link" href="gstreamer-GstSegment.html#gst-segment-copy-into" title="gst_segment_copy_into ()">gst_segment_copy_into</a> (<em class="parameter"><code>const <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *src</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *dest</code></em>);
</pre>
</div>
<div class="refsect1">
<a name="gstreamer-GstSegment.description"></a><h2>Description</h2>
<p>
This helper structure holds the relevant values for tracking the region of
interest in a media file, called a segment.
</p>
<p>
The structure can be used for two purposes:
</p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem"><p>performing seeks (handling seek events)</p></li>
<li class="listitem"><p>tracking playback regions (handling newsegment events)</p></li>
</ul></div>
<p>
</p>
<p>
The segment is usually configured by the application with a seek event which
is propagated upstream and eventually handled by an element that performs the seek.
</p>
<p>
The configured segment is then propagated back downstream with a newsegment event.
This information is then used to clip media to the segment boundaries.
</p>
<p>
A segment structure is initialized with <a class="link" href="gstreamer-GstSegment.html#gst-segment-init" title="gst_segment_init ()"><code class="function">gst_segment_init()</code></a>, which takes a <a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a>
that will be used as the format of the segment values. The segment will be configured
with a start value of 0 and a stop/duration of -1, which is undefined. The default
rate and applied_rate is 1.0.
</p>
<p>
The public duration field contains the duration of the segment. When using
the segment for seeking, the start and time members should normally be left
to their default 0 value. The stop position is left to -1 unless explicitly
configured to a different value after a seek event.
</p>
<p>
The current position in the segment should be set by changing the position
member in the structure.
</p>
<p>
For elements that perform seeks, the current segment should be updated with the
<a class="link" href="gstreamer-GstSegment.html#gst-segment-do-seek" title="gst_segment_do_seek ()"><code class="function">gst_segment_do_seek()</code></a> and the values from the seek event. This method will update
all the segment fields. The position field will contain the new playback position.
If the start_type was different from GST_SEEK_TYPE_NONE, playback continues from
the position position, possibly with updated flags or rate.
</p>
<p>
For elements that want to use <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> to track the playback region,
update the segment fields with the information from the newsegment event.
The <a class="link" href="gstreamer-GstSegment.html#gst-segment-clip" title="gst_segment_clip ()"><code class="function">gst_segment_clip()</code></a> method can be used to check and clip
the media data to the segment boundaries.
</p>
<p>
For elements that want to synchronize to the pipeline clock, <a class="link" href="gstreamer-GstSegment.html#gst-segment-to-running-time" title="gst_segment_to_running_time ()"><code class="function">gst_segment_to_running_time()</code></a>
can be used to convert a timestamp to a value that can be used to synchronize
to the clock. This function takes into account the base as well as
any rate or applied_rate conversions.
</p>
<p>
For elements that need to perform operations on media data in stream_time,
<a class="link" href="gstreamer-GstSegment.html#gst-segment-to-stream-time" title="gst_segment_to_stream_time ()"><code class="function">gst_segment_to_stream_time()</code></a> can be used to convert a timestamp and the segment
info to stream time (which is always between 0 and the duration of the stream).
</p>
<p>
Last reviewed on 2012-03-29 (0.11.3)
</p>
</div>
<div class="refsect1">
<a name="gstreamer-GstSegment.details"></a><h2>Details</h2>
<div class="refsect2">
<a name="GstSegment"></a><h3>struct GstSegment</h3>
<pre class="programlisting">struct GstSegment {
GstSegmentFlags flags;
gdouble rate;
gdouble applied_rate;
GstFormat format;
guint64 base;
guint64 offset;
guint64 start;
guint64 stop;
guint64 time;
guint64 position;
guint64 duration;
};
</pre>
<p>
A helper structure that holds the configured region of
interest in a media file.
</p>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term"><a class="link" href="gstreamer-GstSegment.html#GstSegmentFlags" title="enum GstSegmentFlags"><span class="type">GstSegmentFlags</span></a> <em class="structfield"><code><a name="GstSegment.flags"></a>flags</code></em>;</span></p></td>
<td>flags for this segment</td>
</tr>
<tr>
<td><p><span class="term"><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gdouble"><span class="type">gdouble</span></a> <em class="structfield"><code><a name="GstSegment.rate"></a>rate</code></em>;</span></p></td>
<td>the rate of the segment</td>
</tr>
<tr>
<td><p><span class="term"><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gdouble"><span class="type">gdouble</span></a> <em class="structfield"><code><a name="GstSegment.applied-rate"></a>applied_rate</code></em>;</span></p></td>
<td>the already applied rate to the segment</td>
</tr>
<tr>
<td><p><span class="term"><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> <em class="structfield"><code><a name="GstSegment.format"></a>format</code></em>;</span></p></td>
<td>the format of the segment values</td>
</tr>
<tr>
<td><p><span class="term"><span class="type">guint64</span> <em class="structfield"><code><a name="GstSegment.base"></a>base</code></em>;</span></p></td>
<td>the base of the segment</td>
</tr>
<tr>
<td><p><span class="term"><span class="type">guint64</span> <em class="structfield"><code><a name="GstSegment.offset"></a>offset</code></em>;</span></p></td>
<td>the offset to apply to <em class="parameter"><code>start</code></em> or <em class="parameter"><code>stop</code></em>
</td>
</tr>
<tr>
<td><p><span class="term"><span class="type">guint64</span> <em class="structfield"><code><a name="GstSegment.start"></a>start</code></em>;</span></p></td>
<td>the start of the segment</td>
</tr>
<tr>
<td><p><span class="term"><span class="type">guint64</span> <em class="structfield"><code><a name="GstSegment.stop"></a>stop</code></em>;</span></p></td>
<td>the stop of the segment</td>
</tr>
<tr>
<td><p><span class="term"><span class="type">guint64</span> <em class="structfield"><code><a name="GstSegment.time"></a>time</code></em>;</span></p></td>
<td>the stream time of the segment</td>
</tr>
<tr>
<td><p><span class="term"><span class="type">guint64</span> <em class="structfield"><code><a name="GstSegment.position"></a>position</code></em>;</span></p></td>
<td>the position in the segment</td>
</tr>
<tr>
<td><p><span class="term"><span class="type">guint64</span> <em class="structfield"><code><a name="GstSegment.duration"></a>duration</code></em>;</span></p></td>
<td>the duration of the segment</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="GstSegmentFlags"></a><h3>enum GstSegmentFlags</h3>
<pre class="programlisting">typedef enum {
/*< flags >*/
GST_SEGMENT_FLAG_NONE = GST_SEEK_FLAG_NONE,
GST_SEGMENT_FLAG_RESET = GST_SEEK_FLAG_FLUSH,
GST_SEGMENT_FLAG_SKIP = GST_SEEK_FLAG_SKIP,
GST_SEGMENT_FLAG_SEGMENT = GST_SEEK_FLAG_SEGMENT
} GstSegmentFlags;
</pre>
<p>
Flags for the GstSegment structure. Currently mapped to the corresponding
values of the seek flags.
</p>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><a name="GST-SEGMENT-FLAG-NONE:CAPS"></a><span class="term"><code class="literal">GST_SEGMENT_FLAG_NONE</code></span></p></td>
<td>no flags
</td>
</tr>
<tr>
<td><p><a name="GST-SEGMENT-FLAG-RESET:CAPS"></a><span class="term"><code class="literal">GST_SEGMENT_FLAG_RESET</code></span></p></td>
<td>reset the pipeline running_time to the segment
running_time
</td>
</tr>
<tr>
<td><p><a name="GST-SEGMENT-FLAG-SKIP:CAPS"></a><span class="term"><code class="literal">GST_SEGMENT_FLAG_SKIP</code></span></p></td>
<td>perform skip playback
</td>
</tr>
<tr>
<td><p><a name="GST-SEGMENT-FLAG-SEGMENT:CAPS"></a><span class="term"><code class="literal">GST_SEGMENT_FLAG_SEGMENT</code></span></p></td>
<td>send SEGMENT_DONE instead of EOS
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gst-segment-clip"></a><h3>gst_segment_clip ()</h3>
<pre class="programlisting"><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a> gst_segment_clip (<em class="parameter"><code>const <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *segment</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>,
<em class="parameter"><code><span class="type">guint64</span> start</code></em>,
<em class="parameter"><code><span class="type">guint64</span> stop</code></em>,
<em class="parameter"><code><span class="type">guint64</span> *clip_start</code></em>,
<em class="parameter"><code><span class="type">guint64</span> *clip_stop</code></em>);</pre>
<p>
Clip the given <em class="parameter"><code>start</code></em> and <em class="parameter"><code>stop</code></em> values to the segment boundaries given
in <em class="parameter"><code>segment</code></em>. <em class="parameter"><code>start</code></em> and <em class="parameter"><code>stop</code></em> are compared and clipped to <em class="parameter"><code>segment</code></em>
start and stop values.
</p>
<p>
If the function returns FALSE, <em class="parameter"><code>start</code></em> and <em class="parameter"><code>stop</code></em> are known to fall
outside of <em class="parameter"><code>segment</code></em> and <em class="parameter"><code>clip_start</code></em> and <em class="parameter"><code>clip_stop</code></em> are not updated.
</p>
<p>
When the function returns TRUE, <em class="parameter"><code>clip_start</code></em> and <em class="parameter"><code>clip_stop</code></em> will be
updated. If <em class="parameter"><code>clip_start</code></em> or <em class="parameter"><code>clip_stop</code></em> are different from <em class="parameter"><code>start</code></em> or <em class="parameter"><code>stop</code></em>
respectively, the region fell partially in the segment.
</p>
<p>
Note that when <em class="parameter"><code>stop</code></em> is -1, <em class="parameter"><code>clip_stop</code></em> will be set to the end of the
segment. Depending on the use case, this may or may not be what you want.
</p>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>segment</code></em> :</span></p></td>
<td>a <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> structure.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>format</code></em> :</span></p></td>
<td>the format of the segment.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>start</code></em> :</span></p></td>
<td>the start position in the segment</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>stop</code></em> :</span></p></td>
<td>the stop position in the segment</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>clip_start</code></em> :</span></p></td>
<td>the clipped start position in the segment. <span class="annotation">[<acronym title="Parameter for returning results. Default is transfer full."><span class="acronym">out</span></acronym>][<acronym title="NULL is ok, both for passing and for returning."><span class="acronym">allow-none</span></acronym>]</span>
</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>clip_stop</code></em> :</span></p></td>
<td>the clipped stop position in the segment. <span class="annotation">[<acronym title="Parameter for returning results. Default is transfer full."><span class="acronym">out</span></acronym>][<acronym title="NULL is ok, both for passing and for returning."><span class="acronym">allow-none</span></acronym>]</span>
</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>TRUE if the given <em class="parameter"><code>start</code></em> and <em class="parameter"><code>stop</code></em> times fall partially or
completely in <em class="parameter"><code>segment</code></em>, FALSE if the values are completely outside
of the segment.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gst-segment-init"></a><h3>gst_segment_init ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gst_segment_init (<em class="parameter"><code><a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *segment</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>);</pre>
<p>
The start/position fields are set to 0 and the stop/duration
fields are set to -1 (unknown). The default rate of 1.0 and no
flags are set.
</p>
<p>
Initialize <em class="parameter"><code>segment</code></em> to its default values.
</p>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>segment</code></em> :</span></p></td>
<td>a <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> structure.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>format</code></em> :</span></p></td>
<td>the format of the segment.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gst-segment-new"></a><h3>gst_segment_new ()</h3>
<pre class="programlisting"><a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="returnvalue">GstSegment</span></a> * gst_segment_new (<em class="parameter"><code><span class="type">void</span></code></em>);</pre>
<p>
Allocate a new <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> structure and initialize it using
<a class="link" href="gstreamer-GstSegment.html#gst-segment-init" title="gst_segment_init ()"><code class="function">gst_segment_init()</code></a>.
</p>
<p>
Free-function: gst_segment_free
</p>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody><tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>a new <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a>, free with <a class="link" href="gstreamer-GstSegment.html#gst-segment-free" title="gst_segment_free ()"><code class="function">gst_segment_free()</code></a>. <span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span>
</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gst-segment-copy"></a><h3>gst_segment_copy ()</h3>
<pre class="programlisting"><a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="returnvalue">GstSegment</span></a> * gst_segment_copy (<em class="parameter"><code>const <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *segment</code></em>);</pre>
<p>
Create a copy of given <em class="parameter"><code>segment</code></em>.
</p>
<p>
Free-function: gst_segment_free
</p>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>segment</code></em> :</span></p></td>
<td>a <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a>. <span class="annotation">[<acronym title="Don't free data after the code is done."><span class="acronym">transfer none</span></acronym>]</span>
</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>a new <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a>, free with <a class="link" href="gstreamer-GstSegment.html#gst-segment-free" title="gst_segment_free ()"><code class="function">gst_segment_free()</code></a>. <span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span>
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gst-segment-free"></a><h3>gst_segment_free ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gst_segment_free (<em class="parameter"><code><a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *segment</code></em>);</pre>
<p>
Free the allocated segment <em class="parameter"><code>segment</code></em>.
</p>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>segment</code></em> :</span></p></td>
<td>a <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a>. <span class="annotation">[<acronym title="Parameter for input. Default is transfer none."><span class="acronym">in</span></acronym>][<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span>
</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gst-segment-do-seek"></a><h3>gst_segment_do_seek ()</h3>
<pre class="programlisting"><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a> gst_segment_do_seek (<em class="parameter"><code><a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *segment</code></em>,
<em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gdouble"><span class="type">gdouble</span></a> rate</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstEvent.html#GstSeekFlags" title="enum GstSeekFlags"><span class="type">GstSeekFlags</span></a> flags</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstEvent.html#GstSeekType" title="enum GstSeekType"><span class="type">GstSeekType</span></a> start_type</code></em>,
<em class="parameter"><code><span class="type">guint64</span> start</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstEvent.html#GstSeekType" title="enum GstSeekType"><span class="type">GstSeekType</span></a> stop_type</code></em>,
<em class="parameter"><code><span class="type">guint64</span> stop</code></em>,
<em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> *update</code></em>);</pre>
<p>
Update the segment structure with the field values of a seek event (see
<a class="link" href="gstreamer-GstEvent.html#gst-event-new-seek" title="gst_event_new_seek ()"><code class="function">gst_event_new_seek()</code></a>).
</p>
<p>
After calling this method, the segment field position and time will
contain the requested new position in the segment. The new requested
position in the segment depends on <em class="parameter"><code>rate</code></em> and <em class="parameter"><code>start_type</code></em> and <em class="parameter"><code>stop_type</code></em>.
</p>
<p>
For positive <em class="parameter"><code>rate</code></em>, the new position in the segment is the new <em class="parameter"><code>segment</code></em>
start field when it was updated with a <em class="parameter"><code>start_type</code></em> different from
<a class="link" href="gstreamer-GstEvent.html#GST-SEEK-TYPE-NONE:CAPS"><span class="type">GST_SEEK_TYPE_NONE</span></a>. If no update was performed on <em class="parameter"><code>segment</code></em> start position
(<a class="link" href="gstreamer-GstEvent.html#GST-SEEK-TYPE-NONE:CAPS"><span class="type">GST_SEEK_TYPE_NONE</span></a>), <em class="parameter"><code>start</code></em> is ignored and <em class="parameter"><code>segment</code></em> position is
unmodified.
</p>
<p>
For negative <em class="parameter"><code>rate</code></em>, the new position in the segment is the new <em class="parameter"><code>segment</code></em>
stop field when it was updated with a <em class="parameter"><code>stop_type</code></em> different from
<a class="link" href="gstreamer-GstEvent.html#GST-SEEK-TYPE-NONE:CAPS"><span class="type">GST_SEEK_TYPE_NONE</span></a>. If no stop was previously configured in the segment, the
duration of the segment will be used to update the stop position.
If no update was performed on <em class="parameter"><code>segment</code></em> stop position (<a class="link" href="gstreamer-GstEvent.html#GST-SEEK-TYPE-NONE:CAPS"><span class="type">GST_SEEK_TYPE_NONE</span></a>),
<em class="parameter"><code>stop</code></em> is ignored and <em class="parameter"><code>segment</code></em> position is unmodified.
</p>
<p>
The applied rate of the segment will be set to 1.0 by default.
If the caller can apply a rate change, it should update <em class="parameter"><code>segment</code></em>
rate and applied_rate after calling this function.
</p>
<p>
<em class="parameter"><code>update</code></em> will be set to TRUE if a seek should be performed to the segment
position field. This field can be FALSE if, for example, only the <em class="parameter"><code>rate</code></em>
has been changed but not the playback position.
</p>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>segment</code></em> :</span></p></td>
<td>a <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> structure.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>rate</code></em> :</span></p></td>
<td>the rate of the segment.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>format</code></em> :</span></p></td>
<td>the format of the segment.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>flags</code></em> :</span></p></td>
<td>the segment flags for the segment</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>start_type</code></em> :</span></p></td>
<td>the seek method</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>start</code></em> :</span></p></td>
<td>the seek start value</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>stop_type</code></em> :</span></p></td>
<td>the seek method</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>stop</code></em> :</span></p></td>
<td>the seek stop value</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>update</code></em> :</span></p></td>
<td>boolean holding whether position was updated.</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>
<a href="http://library.gnome.org/devel/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> if the seek could be performed.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gst-segment-to-running-time"></a><h3>gst_segment_to_running_time ()</h3>
<pre class="programlisting"><span class="returnvalue">guint64</span> gst_segment_to_running_time (<em class="parameter"><code>const <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *segment</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>,
<em class="parameter"><code><span class="type">guint64</span> position</code></em>);</pre>
<p>
Translate <em class="parameter"><code>position</code></em> to the total running time using the currently configured
segment. Position is a value between <em class="parameter"><code>segment</code></em> start and stop time.
</p>
<p>
This function is typically used by elements that need to synchronize to the
global clock in a pipeline. The runnning time is a constantly increasing value
starting from 0. When <a class="link" href="gstreamer-GstSegment.html#gst-segment-init" title="gst_segment_init ()"><code class="function">gst_segment_init()</code></a> is called, this value will reset to
0.
</p>
<p>
This function returns -1 if the position is outside of <em class="parameter"><code>segment</code></em> start and stop.
</p>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>segment</code></em> :</span></p></td>
<td>a <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> structure.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>format</code></em> :</span></p></td>
<td>the format of the segment.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>position</code></em> :</span></p></td>
<td>the position in the segment</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>the position as the total running time or -1 when an invalid position
was given.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gst-segment-to-stream-time"></a><h3>gst_segment_to_stream_time ()</h3>
<pre class="programlisting"><span class="returnvalue">guint64</span> gst_segment_to_stream_time (<em class="parameter"><code>const <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *segment</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>,
<em class="parameter"><code><span class="type">guint64</span> position</code></em>);</pre>
<p>
Translate <em class="parameter"><code>position</code></em> to stream time using the currently configured
segment. The <em class="parameter"><code>position</code></em> value must be between <em class="parameter"><code>segment</code></em> start and
stop value.
</p>
<p>
This function is typically used by elements that need to operate on
the stream time of the buffers it receives, such as effect plugins.
In those use cases, <em class="parameter"><code>position</code></em> is typically the buffer timestamp or
clock time that one wants to convert to the stream time.
The stream time is always between 0 and the total duration of the
media stream.
</p>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>segment</code></em> :</span></p></td>
<td>a <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> structure.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>format</code></em> :</span></p></td>
<td>the format of the segment.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>position</code></em> :</span></p></td>
<td>the position in the segment</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>the position in stream_time or -1 when an invalid position
was given.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gst-segment-to-position"></a><h3>gst_segment_to_position ()</h3>
<pre class="programlisting"><span class="returnvalue">guint64</span> gst_segment_to_position (<em class="parameter"><code>const <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *segment</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>,
<em class="parameter"><code><span class="type">guint64</span> running_time</code></em>);</pre>
<p>
Convert <em class="parameter"><code>running_time</code></em> into a position in the segment so that
<a class="link" href="gstreamer-GstSegment.html#gst-segment-to-running-time" title="gst_segment_to_running_time ()"><code class="function">gst_segment_to_running_time()</code></a> with that position returns <em class="parameter"><code>running_time</code></em>.
</p>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>segment</code></em> :</span></p></td>
<td>a <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> structure.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>format</code></em> :</span></p></td>
<td>the format of the segment.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>running_time</code></em> :</span></p></td>
<td>the running_time in the segment</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>the position in the segment for <em class="parameter"><code>running_time</code></em>. This function returns
-1 when <em class="parameter"><code>running_time</code></em> is -1 or when it is not inside <em class="parameter"><code>segment</code></em>.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gst-segment-set-running-time"></a><h3>gst_segment_set_running_time ()</h3>
<pre class="programlisting"><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a> gst_segment_set_running_time (<em class="parameter"><code><a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *segment</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstFormat.html#GstFormat" title="enum GstFormat"><span class="type">GstFormat</span></a> format</code></em>,
<em class="parameter"><code><span class="type">guint64</span> running_time</code></em>);</pre>
<p>
Adjust the start/stop and base values of <em class="parameter"><code>segment</code></em> such that the next valid
buffer will be one with <em class="parameter"><code>running_time</code></em>.
</p>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>segment</code></em> :</span></p></td>
<td>a <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> structure.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>format</code></em> :</span></p></td>
<td>the format of the segment.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>running_time</code></em> :</span></p></td>
<td>the running_time in the segment</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>
<a href="http://library.gnome.org/devel/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> if the segment could be updated successfully. If <a href="http://library.gnome.org/devel/glib/unstable/glib-Standard-Macros.html#FALSE:CAPS"><code class="literal">FALSE</code></a> is
returned, <em class="parameter"><code>running_time</code></em> is -1 or not in <em class="parameter"><code>segment</code></em>.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="gst-segment-copy-into"></a><h3>gst_segment_copy_into ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> gst_segment_copy_into (<em class="parameter"><code>const <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *src</code></em>,
<em class="parameter"><code><a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a> *dest</code></em>);</pre>
<p>
Copy the contents of <em class="parameter"><code>src</code></em> into <em class="parameter"><code>dest</code></em>.
</p>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>src</code></em> :</span></p></td>
<td>a <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a>. <span class="annotation">[<acronym title="Don't free data after the code is done."><span class="acronym">transfer none</span></acronym>]</span>
</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>dest</code></em> :</span></p></td>
<td>a <a class="link" href="gstreamer-GstSegment.html#GstSegment" title="struct GstSegment"><span class="type">GstSegment</span></a>. <span class="annotation">[<acronym title="Don't free data after the code is done."><span class="acronym">transfer none</span></acronym>]</span>
</td>
</tr>
</tbody>
</table></div>
</div>
</div>
<div class="refsect1">
<a name="gstreamer-GstSegment.see-also"></a><h2>See Also</h2>
<a class="link" href="gstreamer-GstEvent.html#GstEvent" title="struct GstEvent"><span class="type">GstEvent</span></a>
</div>
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