Google Git
Sign in
coral / mtk-gstreamer-debian / fa1e60a5264d9f8ef0bba1022545b00159b6e884 / . / docs / libs / html / GstBaseParse.html
blob: 663ef32b7a2e608453623a8d20d2aec7ebd84263 [file] [log] [blame]
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>GstBaseParse: GStreamer 1.0 Library Reference Manual</title>
<meta name="generator" content="DocBook XSL Stylesheets V1.78.1">
<link rel="home" href="index.html" title="GStreamer 1.0 Library Reference Manual">
<link rel="up" href="gstreamer-base.html" title="GStreamer Base and Utillity Classes">
<link rel="prev" href="gstreamer-base.html" title="GStreamer Base and Utillity Classes">
<link rel="next" href="GstBaseSrc.html" title="GstBaseSrc">
<meta name="generator" content="GTK-Doc V1.24 (XML mode)">
<link rel="stylesheet" href="style.css" type="text/css">
</head>
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
<table class="navigation" id="top" width="100%" summary="Navigation header" cellpadding="2" cellspacing="5"><tr valign="middle">
<td width="100%" align="left" class="shortcuts">
<a href="#" class="shortcut">Top</a><span id="nav_description">  <span class="dim">|</span> 
<a href="#GstBaseParse.description" class="shortcut">Description</a></span><span id="nav_hierarchy">  <span class="dim">|</span> 
<a href="#GstBaseParse.object-hierarchy" class="shortcut">Object Hierarchy</a></span><span id="nav_properties">  <span class="dim">|</span> 
<a href="#GstBaseParse.properties" class="shortcut">Properties</a></span>
</td>
<td><a accesskey="h" href="index.html"><img src="home.png" width="16" height="16" border="0" alt="Home"></a></td>
<td><a accesskey="u" href="gstreamer-base.html"><img src="up.png" width="16" height="16" border="0" alt="Up"></a></td>
<td><a accesskey="p" href="gstreamer-base.html"><img src="left.png" width="16" height="16" border="0" alt="Prev"></a></td>
<td><a accesskey="n" href="GstBaseSrc.html"><img src="right.png" width="16" height="16" border="0" alt="Next"></a></td>
</tr></table>
<div class="refentry">
<a name="GstBaseParse"></a><div class="titlepage"></div>
<div class="refnamediv"><table width="100%"><tr>
<td valign="top">
<h2><span class="refentrytitle"><a name="GstBaseParse.top_of_page"></a>GstBaseParse</span></h2>
<p>GstBaseParse — Base class for stream parsers</p>
</td>
<td class="gallery_image" valign="top" align="right"></td>
</tr></table></div>
<div class="refsect1">
<a name="GstBaseParse.functions"></a><h2>Functions</h2>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="functions_return">
<col class="functions_name">
</colgroup>
<tbody>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#gst-base-parse-set-duration" title="gst_base_parse_set_duration ()">gst_base_parse_set_duration</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#gst-base-parse-set-average-bitrate" title="gst_base_parse_set_average_bitrate ()">gst_base_parse_set_average_bitrate</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#gst-base-parse-set-min-frame-size" title="gst_base_parse_set_min_frame_size ()">gst_base_parse_set_min_frame_size</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#gst-base-parse-set-passthrough" title="gst_base_parse_set_passthrough ()">gst_base_parse_set_passthrough</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#gst-base-parse-set-syncable" title="gst_base_parse_set_syncable ()">gst_base_parse_set_syncable</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#gst-base-parse-set-has-timing-info" title="gst_base_parse_set_has_timing_info ()">gst_base_parse_set_has_timing_info</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#gst-base-parse-set-frame-rate" title="gst_base_parse_set_frame_rate ()">gst_base_parse_set_frame_rate</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#gst-base-parse-set-latency" title="gst_base_parse_set_latency ()">gst_base_parse_set_latency</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#gst-base-parse-set-infer-ts" title="gst_base_parse_set_infer_ts ()">gst_base_parse_set_infer_ts</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#gst-base-parse-set-pts-interpolation" title="gst_base_parse_set_pts_interpolation ()">gst_base_parse_set_pts_interpolation</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#gst-base-parse-set-ts-at-offset" title="gst_base_parse_set_ts_at_offset ()">gst_base_parse_set_ts_at_offset</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#gst-base-parse-convert-default" title="gst_base_parse_convert_default ()">gst_base_parse_convert_default</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#gst-base-parse-add-index-entry" title="gst_base_parse_add_index_entry ()">gst_base_parse_add_index_entry</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="returnvalue">GstBaseParseFrame</span></a> *
</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#gst-base-parse-frame-new" title="gst_base_parse_frame_new ()">gst_base_parse_frame_new</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#gst-base-parse-frame-init" title="gst_base_parse_frame_init ()">gst_base_parse_frame_init</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#gst-base-parse-frame-free" title="gst_base_parse_frame_free ()">gst_base_parse_frame_free</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstPad.html#GstFlowReturn"><span class="returnvalue">GstFlowReturn</span></a>
</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#gst-base-parse-push-frame" title="gst_base_parse_push_frame ()">gst_base_parse_push_frame</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstPad.html#GstFlowReturn"><span class="returnvalue">GstFlowReturn</span></a>
</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#gst-base-parse-finish-frame" title="gst_base_parse_finish_frame ()">gst_base_parse_finish_frame</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#GST-BASE-PARSE-DRAINING:CAPS" title="GST_BASE_PARSE_DRAINING()">GST_BASE_PARSE_DRAINING</a><span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name"><a class="link" href="GstBaseParse.html#GST-BASE-PARSE-FLAG-DRAINING:CAPS" title="GST_BASE_PARSE_FLAG_DRAINING">GST_BASE_PARSE_FLAG_DRAINING</a></td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name"><a class="link" href="GstBaseParse.html#GST-BASE-PARSE-FLAG-LOST-SYNC:CAPS" title="GST_BASE_PARSE_FLAG_LOST_SYNC">GST_BASE_PARSE_FLAG_LOST_SYNC</a></td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#GST-BASE-PARSE-LOST-SYNC:CAPS" title="GST_BASE_PARSE_LOST_SYNC()">GST_BASE_PARSE_LOST_SYNC</a><span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#GST-BASE-PARSE-SINK-PAD:CAPS" title="GST_BASE_PARSE_SINK_PAD()">GST_BASE_PARSE_SINK_PAD</a><span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name">
<a class="link" href="GstBaseParse.html#GST-BASE-PARSE-SRC-PAD:CAPS" title="GST_BASE_PARSE_SRC_PAD()">GST_BASE_PARSE_SRC_PAD</a><span class="c_punctuation">()</span>
</td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect1">
<a name="GstBaseParse.properties"></a><h2>Properties</h2>
<div class="informaltable"><table 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="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></td>
<td class="property_name"><a class="link" href="GstBaseParse.html#GstBaseParse--disable-passthrough" title="The “disable-passthrough” property">disable-passthrough</a></td>
<td class="property_flags">Read / Write</td>
</tr></tbody>
</table></div>
</div>
<div class="refsect1">
<a name="GstBaseParse.other"></a><h2>Types and Values</h2>
<div class="informaltable"><table 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="GstBaseParse.html#GstBaseParse-struct" title="struct GstBaseParse">GstBaseParse</a></td>
</tr>
<tr>
<td class="datatype_keyword">struct</td>
<td class="function_name"><a class="link" href="GstBaseParse.html#GstBaseParseClass" title="struct GstBaseParseClass">GstBaseParseClass</a></td>
</tr>
<tr>
<td class="datatype_keyword"> </td>
<td class="function_name"><a class="link" href="GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame">GstBaseParseFrame</a></td>
</tr>
<tr>
<td class="datatype_keyword">enum</td>
<td class="function_name"><a class="link" href="GstBaseParse.html#GstBaseParseFrameFlags" title="enum GstBaseParseFrameFlags">GstBaseParseFrameFlags</a></td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name"><a class="link" href="GstBaseParse.html#GST-BASE-PARSE-FLOW-DROPPED:CAPS" title="GST_BASE_PARSE_FLOW_DROPPED">GST_BASE_PARSE_FLOW_DROPPED</a></td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect1">
<a name="GstBaseParse.object-hierarchy"></a><h2>Object Hierarchy</h2>
<pre class="screen"> <a href="https://developer.gnome.org/gobject/unstable/gobject-The-Base-Object-Type.html#GObject">GObject</a>
<span class="lineart">╰──</span> <a href="https://developer.gnome.org/gobject/unstable/gobject-The-Base-Object-Type.html#GInitiallyUnowned">GInitiallyUnowned</a>
<span class="lineart">╰──</span> <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstObject.html">GstObject</a>
<span class="lineart">╰──</span> <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstElement.html">GstElement</a>
<span class="lineart">╰──</span> GstBaseParse
</pre>
</div>
<div class="refsect1">
<a name="GstBaseParse.includes"></a><h2>Includes</h2>
<pre class="synopsis">#include &lt;gst/base/gstbaseparse.h&gt;
</pre>
</div>
<div class="refsect1">
<a name="GstBaseParse.description"></a><h2>Description</h2>
<p>This base class is for parser elements that process data and splits it
into separate audio/video/whatever frames.</p>
<p>It provides for:</p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem"><p>provides one sink pad and one source pad</p></li>
<li class="listitem"><p>handles state changes</p></li>
<li class="listitem"><p>can operate in pull mode or push mode</p></li>
<li class="listitem"><p>handles seeking in both modes</p></li>
<li class="listitem"><p>handles events (SEGMENT/EOS/FLUSH)</p></li>
<li class="listitem"><p>
handles queries (POSITION/DURATION/SEEKING/FORMAT/CONVERT)
</p></li>
<li class="listitem"><p>handles flushing</p></li>
</ul></div>
<p>The purpose of this base class is to provide the basic functionality of
a parser and share a lot of rather complex code.</p>
<p>Description of the parsing mechanism:</p>
<div class="orderedlist"><ol class="orderedlist" type="1">
<li class="listitem"><div class="itemizedlist">
<p class="title"><b>Set-up phase</b></p>
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem"><p>
<a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> calls <em class="parameter"><code>start</code></em> to inform subclass that data processing is
about to start now.
</p></li>
<li class="listitem"><p>
<a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> class calls <em class="parameter"><code>set_sink_caps</code></em> to inform the subclass about
incoming sinkpad caps. Subclass could already set the srcpad caps
accordingly, but this might be delayed until calling
<a class="link" href="GstBaseParse.html#gst-base-parse-finish-frame" title="gst_base_parse_finish_frame ()"><code class="function">gst_base_parse_finish_frame()</code></a> with a non-queued frame.
</p></li>
<li class="listitem"><p>
At least at this point subclass needs to tell the <a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> class
how big data chunks it wants to receive (min_frame_size). It can do
this with <a class="link" href="GstBaseParse.html#gst-base-parse-set-min-frame-size" title="gst_base_parse_set_min_frame_size ()"><code class="function">gst_base_parse_set_min_frame_size()</code></a>.
</p></li>
<li class="listitem"><p>
<a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> class sets up appropriate data passing mode (pull/push)
and starts to process the data.
</p></li>
</ul>
</div></li>
<li class="listitem"><div class="itemizedlist">
<p class="title"><b>Parsing phase</b></p>
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem"><p>
<a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> gathers at least min_frame_size bytes of data either
by pulling it from upstream or collecting buffers in an internal
<a class="link" href="GstAdapter.html" title="GstAdapter"><span class="type">GstAdapter</span></a>.
</p></li>
<li class="listitem">
<p>
A buffer of (at least) min_frame_size bytes is passed to subclass with
<em class="parameter"><code>handle_frame</code></em>. Subclass checks the contents and can optionally
return GST_FLOW_OK along with an amount of data to be skipped to find
a valid frame (which will result in a subsequent DISCONT).
If, otherwise, the buffer does not hold a complete frame,
<em class="parameter"><code>handle_frame</code></em> can merely return and will be called again when additional
data is available. In push mode this amounts to an
additional input buffer (thus minimal additional latency), in pull mode
this amounts to some arbitrary reasonable buffer size increase.
Of course, <a class="link" href="GstBaseParse.html#gst-base-parse-set-min-frame-size" title="gst_base_parse_set_min_frame_size ()"><code class="function">gst_base_parse_set_min_frame_size()</code></a> could also be used if a
very specific known amount of additional data is required.
If, however, the buffer holds a complete valid frame, it can pass
the size of this frame to <a class="link" href="GstBaseParse.html#gst-base-parse-finish-frame" title="gst_base_parse_finish_frame ()"><code class="function">gst_base_parse_finish_frame()</code></a>.
If acting as a converter, it can also merely indicate consumed input data
while simultaneously providing custom output data.
Note that baseclass performs some processing (such as tracking
overall consumed data rate versus duration) for each finished frame,
but other state is only updated upon each call to <em class="parameter"><code>handle_frame</code></em>
(such as tracking upstream input timestamp).
</p>
<p>
Subclass is also responsible for setting the buffer metadata
(e.g. buffer timestamp and duration, or keyframe if applicable).
(although the latter can also be done by <a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> if it is
appropriately configured, see below). Frame is provided with
timestamp derived from upstream (as much as generally possible),
duration obtained from configuration (see below), and offset
if meaningful (in pull mode).
</p>
<p>
Note that <em class="parameter"><code>check_valid_frame</code></em> might receive any small
amount of input data when leftover data is being drained (e.g. at EOS).
</p>
</li>
<li class="listitem"><p>
As part of finish frame processing,
just prior to actually pushing the buffer in question,
it is passed to <em class="parameter"><code>pre_push_frame</code></em> which gives subclass yet one
last chance to examine buffer metadata, or to send some custom (tag)
events, or to perform custom (segment) filtering.
</p></li>
<li class="listitem"><p>
During the parsing process <a class="link" href="GstBaseParse.html#GstBaseParseClass" title="struct GstBaseParseClass"><span class="type">GstBaseParseClass</span></a> will handle both srcpad
and sinkpad events. They will be passed to subclass if <em class="parameter"><code>event</code></em> or
<em class="parameter"><code>src_event</code></em> callbacks have been provided.
</p></li>
</ul>
</div></li>
<li class="listitem"><div class="itemizedlist">
<p class="title"><b>Shutdown phase</b></p>
<ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
<a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> class calls <em class="parameter"><code>stop</code></em> to inform the subclass that data
parsing will be stopped.
</p></li></ul>
</div></li>
</ol></div>
<p>Subclass is responsible for providing pad template caps for
source and sink pads. The pads need to be named "sink" and "src". It also
needs to set the fixed caps on srcpad, when the format is ensured (e.g.
when base class calls subclass' <em class="parameter"><code>set_sink_caps</code></em>
function).</p>
<p>This base class uses <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstFormat.html#GST-FORMAT-DEFAULT:CAPS"><code class="literal">GST_FORMAT_DEFAULT</code></a> as a meaning of frames. So,
subclass conversion routine needs to know that conversion from
<a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstFormat.html#GST-FORMAT-TIME:CAPS"><code class="literal">GST_FORMAT_TIME</code></a> to <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstFormat.html#GST-FORMAT-DEFAULT:CAPS"><code class="literal">GST_FORMAT_DEFAULT</code></a> must return the
frame number that can be found from the given byte position.</p>
<p><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> uses subclasses conversion methods also for seeking (or
otherwise uses its own default one, see also below).</p>
<p>Subclass <em class="parameter"><code>start</code></em>
and <em class="parameter"><code>stop</code></em>
functions will be called to inform the beginning
and end of data processing.</p>
<p>Things that subclass need to take care of:</p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem"><p>Provide pad templates</p></li>
<li class="listitem"><p>
Fixate the source pad caps when appropriate
</p></li>
<li class="listitem"><p>
Inform base class how big data chunks should be retrieved. This is
done with <a class="link" href="GstBaseParse.html#gst-base-parse-set-min-frame-size" title="gst_base_parse_set_min_frame_size ()"><code class="function">gst_base_parse_set_min_frame_size()</code></a> function.
</p></li>
<li class="listitem"><p>
Examine data chunks passed to subclass with <em class="parameter"><code>handle_frame</code></em> and pass
proper frame(s) to <a class="link" href="GstBaseParse.html#gst-base-parse-finish-frame" title="gst_base_parse_finish_frame ()"><code class="function">gst_base_parse_finish_frame()</code></a>, and setting src pad
caps and timestamps on frame.
</p></li>
<li class="listitem"><p>Provide conversion functions</p></li>
<li class="listitem"><p>
Update the duration information with <a class="link" href="GstBaseParse.html#gst-base-parse-set-duration" title="gst_base_parse_set_duration ()"><code class="function">gst_base_parse_set_duration()</code></a>
</p></li>
<li class="listitem"><p>
Optionally passthrough using <a class="link" href="GstBaseParse.html#gst-base-parse-set-passthrough" title="gst_base_parse_set_passthrough ()"><code class="function">gst_base_parse_set_passthrough()</code></a>
</p></li>
<li class="listitem"><p>
Configure various baseparse parameters using
<a class="link" href="GstBaseParse.html#gst-base-parse-set-average-bitrate" title="gst_base_parse_set_average_bitrate ()"><code class="function">gst_base_parse_set_average_bitrate()</code></a>, <a class="link" href="GstBaseParse.html#gst-base-parse-set-syncable" title="gst_base_parse_set_syncable ()"><code class="function">gst_base_parse_set_syncable()</code></a>
and <a class="link" href="GstBaseParse.html#gst-base-parse-set-frame-rate" title="gst_base_parse_set_frame_rate ()"><code class="function">gst_base_parse_set_frame_rate()</code></a>.
</p></li>
<li class="listitem"><p>
In particular, if subclass is unable to determine a duration, but
parsing (or specs) yields a frames per seconds rate, then this can be
provided to <a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> to enable it to cater for
buffer time metadata (which will be taken from upstream as much as
possible). Internally keeping track of frame durations and respective
sizes that have been pushed provides <a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> with an estimated
bitrate. A default <em class="parameter"><code>convert</code></em> (used if not overridden) will then use these
rates to perform obvious conversions. These rates are also used to
update (estimated) duration at regular frame intervals.
</p></li>
</ul></div>
</div>
<div class="refsect1">
<a name="GstBaseParse.functions_details"></a><h2>Functions</h2>
<div class="refsect2">
<a name="gst-base-parse-set-duration"></a><h3>gst_base_parse_set_duration ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_base_parse_set_duration (<em class="parameter"><code><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>,
<em class="parameter"><code><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstFormat.html#GstFormat"><span class="type">GstFormat</span></a> fmt</code></em>,
<em class="parameter"><code><span class="type">gint64</span> duration</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gint"><span class="type">gint</span></a> interval</code></em>);</pre>
<p>Sets the duration of the currently playing media. Subclass can use this
when it is able to determine duration and/or notices a change in the media
duration. Alternatively, if <em class="parameter"><code>interval</code></em>
is non-zero (default), then stream
duration is determined based on estimated bitrate, and updated every <em class="parameter"><code>interval</code></em>
frames.</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.2.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>parse</p></td>
<td class="parameter_description"><p><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a>.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>fmt</p></td>
<td class="parameter_description"><p><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstFormat.html#GstFormat"><span class="type">GstFormat</span></a>.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>duration</p></td>
<td class="parameter_description"><p>duration value.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>interval</p></td>
<td class="parameter_description"><p>how often to update the duration estimate based on bitrate, or 0.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-base-parse-set-average-bitrate"></a><h3>gst_base_parse_set_average_bitrate ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_base_parse_set_average_bitrate (<em class="parameter"><code><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#guint"><span class="type">guint</span></a> bitrate</code></em>);</pre>
<p>Optionally sets the average bitrate detected in media (if non-zero),
e.g. based on metadata, as it will be posted to the application.</p>
<p>By default, announced average bitrate is estimated. The average bitrate
is used to estimate the total duration of the stream and to estimate
a seek position, if there's no index and the format is syncable
(see <a class="link" href="GstBaseParse.html#gst-base-parse-set-syncable" title="gst_base_parse_set_syncable ()"><code class="function">gst_base_parse_set_syncable()</code></a>).</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.3.6"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>parse</p></td>
<td class="parameter_description"><p><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a>.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>bitrate</p></td>
<td class="parameter_description"><p>average bitrate in bits/second</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-base-parse-set-min-frame-size"></a><h3>gst_base_parse_set_min_frame_size ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_base_parse_set_min_frame_size (<em class="parameter"><code><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#guint"><span class="type">guint</span></a> min_size</code></em>);</pre>
<p>Subclass can use this function to tell the base class that it needs to
give at least <span class="type">min_size</span> buffers.</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.4.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>parse</p></td>
<td class="parameter_description"><p><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a>.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>min_size</p></td>
<td class="parameter_description"><p>Minimum size of the data that this base class should give to
subclass.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-base-parse-set-passthrough"></a><h3>gst_base_parse_set_passthrough ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_base_parse_set_passthrough (<em class="parameter"><code><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> passthrough</code></em>);</pre>
<p>Set if the nature of the format or configuration does not allow (much)
parsing, and the parser should operate in passthrough mode (which only
applies when operating in push mode). That is, incoming buffers are
pushed through unmodified, i.e. no <em class="parameter"><code>check_valid_frame</code></em>
or <em class="parameter"><code>parse_frame</code></em>
callbacks will be invoked, but <em class="parameter"><code>pre_push_frame</code></em>
will still be invoked,
so subclass can perform as much or as little is appropriate for
passthrough semantics in <em class="parameter"><code>pre_push_frame</code></em>
.</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.5.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>parse</p></td>
<td class="parameter_description"><p>a <a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>passthrough</p></td>
<td class="parameter_description"><p><a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> if parser should run in passthrough mode</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-base-parse-set-syncable"></a><h3>gst_base_parse_set_syncable ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_base_parse_set_syncable (<em class="parameter"><code><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> syncable</code></em>);</pre>
<p>Set if frame starts can be identified. This is set by default and
determines whether seeking based on bitrate averages
is possible for a format/stream.</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.6.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>parse</p></td>
<td class="parameter_description"><p>a <a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>syncable</p></td>
<td class="parameter_description"><p>set if frame starts can be identified</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-base-parse-set-has-timing-info"></a><h3>gst_base_parse_set_has_timing_info ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_base_parse_set_has_timing_info (<em class="parameter"><code><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> has_timing</code></em>);</pre>
<p>Set if frames carry timing information which the subclass can (generally)
parse and provide. In particular, intrinsic (rather than estimated) time
can be obtained following a seek.</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.7.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>parse</p></td>
<td class="parameter_description"><p>a <a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>has_timing</p></td>
<td class="parameter_description"><p>whether frames carry timing information</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-base-parse-set-frame-rate"></a><h3>gst_base_parse_set_frame_rate ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_base_parse_set_frame_rate (<em class="parameter"><code><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#guint"><span class="type">guint</span></a> fps_num</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#guint"><span class="type">guint</span></a> fps_den</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#guint"><span class="type">guint</span></a> lead_in</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#guint"><span class="type">guint</span></a> lead_out</code></em>);</pre>
<p>If frames per second is configured, parser can take care of buffer duration
and timestamping. When performing segment clipping, or seeking to a specific
location, a corresponding decoder might need an initial <em class="parameter"><code>lead_in</code></em>
and a
following <em class="parameter"><code>lead_out</code></em>
number of frames to ensure the desired segment is
entirely filled upon decoding.</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.8.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>parse</p></td>
<td class="parameter_description"><p>the <a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> to set</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>fps_num</p></td>
<td class="parameter_description"><p>frames per second (numerator).</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>fps_den</p></td>
<td class="parameter_description"><p>frames per second (denominator).</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>lead_in</p></td>
<td class="parameter_description"><p>frames needed before a segment for subsequent decode</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>lead_out</p></td>
<td class="parameter_description"><p>frames needed after a segment</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-base-parse-set-latency"></a><h3>gst_base_parse_set_latency ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_base_parse_set_latency (<em class="parameter"><code><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>,
<em class="parameter"><code><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstClock.html#GstClockTime"><span class="type">GstClockTime</span></a> min_latency</code></em>,
<em class="parameter"><code><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstClock.html#GstClockTime"><span class="type">GstClockTime</span></a> max_latency</code></em>);</pre>
<p>Sets the minimum and maximum (which may likely be equal) latency introduced
by the parsing process. If there is such a latency, which depends on the
particular parsing of the format, it typically corresponds to 1 frame duration.</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.9.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>parse</p></td>
<td class="parameter_description"><p>a <a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>min_latency</p></td>
<td class="parameter_description"><p>minimum parse latency</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>max_latency</p></td>
<td class="parameter_description"><p>maximum parse latency</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-base-parse-set-infer-ts"></a><h3>gst_base_parse_set_infer_ts ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_base_parse_set_infer_ts (<em class="parameter"><code><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> infer_ts</code></em>);</pre>
<p>By default, the base class might try to infer PTS from DTS and vice
versa. While this is generally correct for audio data, it may not
be otherwise. Sub-classes implementing such formats should disable
timestamp inferring.</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.10.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>parse</p></td>
<td class="parameter_description"><p>a <a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>infer_ts</p></td>
<td class="parameter_description"><p><a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> if parser should infer DTS/PTS from each other</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-base-parse-set-pts-interpolation"></a><h3>gst_base_parse_set_pts_interpolation ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_base_parse_set_pts_interpolation (<em class="parameter"><code><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> pts_interpolate</code></em>);</pre>
<p>By default, the base class will guess PTS timestamps using a simple
interpolation (previous timestamp + duration), which is incorrect for
data streams with reordering, where PTS can go backward. Sub-classes
implementing such formats should disable PTS interpolation.</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.11.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>parse</p></td>
<td class="parameter_description"><p>a <a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>pts_interpolate</p></td>
<td class="parameter_description"><p><a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> if parser should interpolate PTS timestamps</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-base-parse-set-ts-at-offset"></a><h3>gst_base_parse_set_ts_at_offset ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_base_parse_set_ts_at_offset (<em class="parameter"><code><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>,
<em class="parameter"><code><span class="type">gsize</span> offset</code></em>);</pre>
<p>This function should only be called from a <em class="parameter"><code>handle_frame</code></em>
implementation.</p>
<p><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> creates initial timestamps for frames by using the last
timestamp seen in the stream before the frame starts. In certain
cases, the correct timestamps will occur in the stream after the
start of the frame, but before the start of the actual picture data.
This function can be used to set the timestamps based on the offset
into the frame data that the picture starts.</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.12.6"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>parse</p></td>
<td class="parameter_description"><p>a <a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>offset</p></td>
<td class="parameter_description"><p>offset into current buffer</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: <a class="link" href="ix05.html#api-index-1.2">1.2</a></p>
</div>
<hr>
<div class="refsect2">
<a name="gst-base-parse-convert-default"></a><h3>gst_base_parse_convert_default ()</h3>
<pre class="programlisting"><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
gst_base_parse_convert_default (<em class="parameter"><code><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>,
<em class="parameter"><code><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstFormat.html#GstFormat"><span class="type">GstFormat</span></a> src_format</code></em>,
<em class="parameter"><code><span class="type">gint64</span> src_value</code></em>,
<em class="parameter"><code><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstFormat.html#GstFormat"><span class="type">GstFormat</span></a> dest_format</code></em>,
<em class="parameter"><code><span class="type">gint64</span> *dest_value</code></em>);</pre>
<p>Default implementation of "convert" vmethod in <a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> class.</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.13.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>parse</p></td>
<td class="parameter_description"><p><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a>.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>src_format</p></td>
<td class="parameter_description"><p><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstFormat.html#GstFormat"><span class="type">GstFormat</span></a> describing the source format.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>src_value</p></td>
<td class="parameter_description"><p>Source value to be converted.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>dest_format</p></td>
<td class="parameter_description"><p><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gstreamer-GstFormat.html#GstFormat"><span class="type">GstFormat</span></a> defining the converted format.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>dest_value</p></td>
<td class="parameter_description"><p>Pointer where the conversion result will be put.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.3.9.13.6"></a><h4>Returns</h4>
<p> <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> if conversion was successful.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-base-parse-add-index-entry"></a><h3>gst_base_parse_add_index_entry ()</h3>
<pre class="programlisting"><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
gst_base_parse_add_index_entry (<em class="parameter"><code><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>,
<em class="parameter"><code><span class="type">guint64</span> offset</code></em>,
<em class="parameter"><code><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstClock.html#GstClockTime"><span class="type">GstClockTime</span></a> ts</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> key</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> force</code></em>);</pre>
<p>Adds an entry to the index associating <em class="parameter"><code>offset</code></em>
to <em class="parameter"><code>ts</code></em>
. It is recommended
to only add keyframe entries. <em class="parameter"><code>force</code></em>
allows to bypass checks, such as
whether the stream is (upstream) seekable, another entry is already "close"
to the new entry, etc.</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.14.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>parse</p></td>
<td class="parameter_description"><p><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a>.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>offset</p></td>
<td class="parameter_description"><p>offset of entry</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>ts</p></td>
<td class="parameter_description"><p>timestamp associated with offset</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>key</p></td>
<td class="parameter_description"><p>whether entry refers to keyframe</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>force</p></td>
<td class="parameter_description"><p>add entry disregarding sanity checks</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.3.9.14.6"></a><h4>Returns</h4>
<p> <a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> indicating whether entry was added</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-base-parse-frame-new"></a><h3>gst_base_parse_frame_new ()</h3>
<pre class="programlisting"><a class="link" href="GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="returnvalue">GstBaseParseFrame</span></a> *
gst_base_parse_frame_new (<em class="parameter"><code><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstBuffer.html"><span class="type">GstBuffer</span></a> *buffer</code></em>,
<em class="parameter"><code><a class="link" href="GstBaseParse.html#GstBaseParseFrameFlags" title="enum GstBaseParseFrameFlags"><span class="type">GstBaseParseFrameFlags</span></a> flags</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gint"><span class="type">gint</span></a> overhead</code></em>);</pre>
<p>Allocates a new <a class="link" href="GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a>. This function is mainly for bindings,
elements written in C should usually allocate the frame on the stack and
then use <a class="link" href="GstBaseParse.html#gst-base-parse-frame-init" title="gst_base_parse_frame_init ()"><code class="function">gst_base_parse_frame_init()</code></a> to initialise it.</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.15.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>buffer</p></td>
<td class="parameter_description"><p> a <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstBuffer.html"><span class="type">GstBuffer</span></a>. </p></td>
<td class="parameter_annotations"><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 class="parameter_name"><p>flags</p></td>
<td class="parameter_description"><p>the flags</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>overhead</p></td>
<td class="parameter_description"><p>number of bytes in this frame which should be counted as
metadata overhead, ie. not used to calculate the average bitrate.
Set to -1 to mark the entire frame as metadata. If in doubt, set to 0.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.3.9.15.6"></a><h4>Returns</h4>
<p> a newly-allocated <a class="link" href="GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a>. Free with
<a class="link" href="GstBaseParse.html#gst-base-parse-frame-free" title="gst_base_parse_frame_free ()"><code class="function">gst_base_parse_frame_free()</code></a> when no longer needed.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-base-parse-frame-init"></a><h3>gst_base_parse_frame_init ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_base_parse_frame_init (<em class="parameter"><code><a class="link" href="GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a> *frame</code></em>);</pre>
<p>Sets a <a class="link" href="GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a> to initial state. Currently this means
all public fields are zero-ed and a private flag is set to make
sure <a class="link" href="GstBaseParse.html#gst-base-parse-frame-free" title="gst_base_parse_frame_free ()"><code class="function">gst_base_parse_frame_free()</code></a> only frees the contents but not
the actual frame. Use this function to initialise a <a class="link" href="GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a>
allocated on the stack.</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.16.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>frame</p></td>
<td class="parameter_description"><p><a class="link" href="GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a>.</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-base-parse-frame-free"></a><h3>gst_base_parse_frame_free ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gst_base_parse_frame_free (<em class="parameter"><code><a class="link" href="GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a> *frame</code></em>);</pre>
</div>
<hr>
<div class="refsect2">
<a name="gst-base-parse-push-frame"></a><h3>gst_base_parse_push_frame ()</h3>
<pre class="programlisting"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstPad.html#GstFlowReturn"><span class="returnvalue">GstFlowReturn</span></a>
gst_base_parse_push_frame (<em class="parameter"><code><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>,
<em class="parameter"><code><a class="link" href="GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a> *frame</code></em>);</pre>
<p>Pushes the frame's buffer downstream, sends any pending events and
does some timestamp and segment handling. Takes ownership of
frame's buffer, though caller retains ownership of <em class="parameter"><code>frame</code></em>
.</p>
<p>This must be called with sinkpad STREAM_LOCK held.</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.18.6"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>parse</p></td>
<td class="parameter_description"><p><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a>.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>frame</p></td>
<td class="parameter_description"><p> a <a class="link" href="GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a>. </p></td>
<td class="parameter_annotations"><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 class="refsect3">
<a name="id-1.2.4.3.9.18.7"></a><h4>Returns</h4>
<p> <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstPad.html#GstFlowReturn"><span class="type">GstFlowReturn</span></a></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gst-base-parse-finish-frame"></a><h3>gst_base_parse_finish_frame ()</h3>
<pre class="programlisting"><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstPad.html#GstFlowReturn"><span class="returnvalue">GstFlowReturn</span></a>
gst_base_parse_finish_frame (<em class="parameter"><code><a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>,
<em class="parameter"><code><a class="link" href="GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a> *frame</code></em>,
<em class="parameter"><code><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gint"><span class="type">gint</span></a> size</code></em>);</pre>
<p>Collects parsed data and pushes this downstream.
Source pad caps must be set when this is called.</p>
<p>If <em class="parameter"><code>frame</code></em>
's out_buffer is set, that will be used as subsequent frame data.
Otherwise, <em class="parameter"><code>size</code></em>
samples will be taken from the input and used for output,
and the output's metadata (timestamps etc) will be taken as (optionally)
set by the subclass on <em class="parameter"><code>frame</code></em>
's (input) buffer (which is otherwise
ignored for any but the above purpose/information).</p>
<p>Note that the latter buffer is invalidated by this call, whereas the
caller retains ownership of <em class="parameter"><code>frame</code></em>
.</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.19.7"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>parse</p></td>
<td class="parameter_description"><p>a <a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>frame</p></td>
<td class="parameter_description"><p>a <a class="link" href="GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a></p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>size</p></td>
<td class="parameter_description"><p>consumed input data represented by frame</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="id-1.2.4.3.9.19.8"></a><h4>Returns</h4>
<p> a <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstPad.html#GstFlowReturn"><span class="type">GstFlowReturn</span></a> that should be escalated to caller (of caller)</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GST-BASE-PARSE-DRAINING:CAPS"></a><h3>GST_BASE_PARSE_DRAINING()</h3>
<pre class="programlisting">#define GST_BASE_PARSE_DRAINING(parse) (!!(GST_BASE_PARSE_CAST(parse)-&gt;flags &amp; GST_BASE_PARSE_FLAG_DRAINING))
</pre>
<p>Obtains current drain status (ie. whether EOS has been received and
the parser is now processing the frames at the end of the stream)</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.20.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>parse</p></td>
<td class="parameter_description"><p>base parse instance</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GST-BASE-PARSE-FLAG-DRAINING:CAPS"></a><h3>GST_BASE_PARSE_FLAG_DRAINING</h3>
<pre class="programlisting">#define GST_BASE_PARSE_FLAG_DRAINING (1 &lt;&lt; 1)
</pre>
</div>
<hr>
<div class="refsect2">
<a name="GST-BASE-PARSE-FLAG-LOST-SYNC:CAPS"></a><h3>GST_BASE_PARSE_FLAG_LOST_SYNC</h3>
<pre class="programlisting">#define GST_BASE_PARSE_FLAG_LOST_SYNC (1 &lt;&lt; 0)
</pre>
</div>
<hr>
<div class="refsect2">
<a name="GST-BASE-PARSE-LOST-SYNC:CAPS"></a><h3>GST_BASE_PARSE_LOST_SYNC()</h3>
<pre class="programlisting">#define GST_BASE_PARSE_LOST_SYNC(parse) (!!(GST_BASE_PARSE_CAST(parse)-&gt;flags &amp; GST_BASE_PARSE_FLAG_LOST_SYNC))
</pre>
<p>Obtains current sync status.</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.23.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>parse</p></td>
<td class="parameter_description"><p>base parse instance</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GST-BASE-PARSE-SINK-PAD:CAPS"></a><h3>GST_BASE_PARSE_SINK_PAD()</h3>
<pre class="programlisting">#define GST_BASE_PARSE_SINK_PAD(obj) (GST_BASE_PARSE_CAST (obj)-&gt;sinkpad)
</pre>
<p>Gives the pointer to the sink <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstPad.html"><span class="type">GstPad</span></a> object of the element.</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.24.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>obj</p></td>
<td class="parameter_description"><p>base parse instance</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GST-BASE-PARSE-SRC-PAD:CAPS"></a><h3>GST_BASE_PARSE_SRC_PAD()</h3>
<pre class="programlisting">#define GST_BASE_PARSE_SRC_PAD(obj) (GST_BASE_PARSE_CAST (obj)-&gt;srcpad)
</pre>
<p>Gives the pointer to the source <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstPad.html"><span class="type">GstPad</span></a> object of the element.</p>
<div class="refsect3">
<a name="id-1.2.4.3.9.25.5"></a><h4>Parameters</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>obj</p></td>
<td class="parameter_description"><p>base parse instance</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
</div>
<div class="refsect1">
<a name="GstBaseParse.other_details"></a><h2>Types and Values</h2>
<div class="refsect2">
<a name="GstBaseParse-struct"></a><h3>struct GstBaseParse</h3>
<pre class="programlisting">struct GstBaseParse {
GstElement element;
};
</pre>
<p>The opaque <a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> data structure.</p>
<div class="refsect3">
<a name="id-1.2.4.3.10.2.5"></a><h4>Members</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="300px" class="struct_members_name">
<col class="struct_members_description">
<col width="200px" class="struct_members_annotations">
</colgroup>
<tbody><tr>
<td class="struct_member_name"><p><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstElement.html"><span class="type">GstElement</span></a> <em class="structfield"><code><a name="GstBaseParse-struct.element"></a>element</code></em>;</p></td>
<td class="struct_member_description"><p>the parent element.</p></td>
<td class="struct_member_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GstBaseParseClass"></a><h3>struct GstBaseParseClass</h3>
<pre class="programlisting">struct GstBaseParseClass {
GstElementClass parent_class;
/* virtual methods for subclasses */
gboolean (*start) (GstBaseParse * parse);
gboolean (*stop) (GstBaseParse * parse);
gboolean (*set_sink_caps) (GstBaseParse * parse,
GstCaps * caps);
GstFlowReturn (*handle_frame) (GstBaseParse * parse,
GstBaseParseFrame * frame,
gint * skipsize);
GstFlowReturn (*pre_push_frame) (GstBaseParse * parse,
GstBaseParseFrame * frame);
gboolean (*convert) (GstBaseParse * parse,
GstFormat src_format,
gint64 src_value,
GstFormat dest_format,
gint64 * dest_value);
gboolean (*sink_event) (GstBaseParse * parse,
GstEvent * event);
gboolean (*src_event) (GstBaseParse * parse,
GstEvent * event);
GstCaps * (*get_sink_caps) (GstBaseParse * parse,
GstCaps * filter);
GstFlowReturn (*detect) (GstBaseParse * parse,
GstBuffer * buffer);
gboolean (*sink_query) (GstBaseParse * parse,
GstQuery * query);
gboolean (*src_query) (GstBaseParse * parse,
GstQuery * query);
};
</pre>
<p>Subclasses can override any of the available virtual methods or not, as
needed. At minimum <em class="parameter"><code>handle_frame</code></em>
needs to be overridden.</p>
<div class="refsect3">
<a name="id-1.2.4.3.10.3.5"></a><h4>Members</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="300px" class="struct_members_name">
<col class="struct_members_description">
<col width="200px" class="struct_members_annotations">
</colgroup>
<tbody>
<tr>
<td class="struct_member_name"><p><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstElement.html#GstElementClass"><span class="type">GstElementClass</span></a> <em class="structfield"><code><a name="GstBaseParseClass.parent-class"></a>parent_class</code></em>;</p></td>
<td class="struct_member_description"><p>the parent class</p></td>
<td class="struct_member_annotations"> </td>
</tr>
<tr>
<td class="struct_member_name"><p><em class="structfield"><code><a name="GstBaseParseClass.start"></a>start</code></em> ()</p></td>
<td class="struct_member_description"><p>Optional.
Called when the element starts processing.
Allows opening external resources.</p></td>
<td class="struct_member_annotations"> </td>
</tr>
<tr>
<td class="struct_member_name"><p><em class="structfield"><code><a name="GstBaseParseClass.stop"></a>stop</code></em> ()</p></td>
<td class="struct_member_description"><p>Optional.
Called when the element stops processing.
Allows closing external resources.</p></td>
<td class="struct_member_annotations"> </td>
</tr>
<tr>
<td class="struct_member_name"><p><em class="structfield"><code><a name="GstBaseParseClass.set-sink-caps"></a>set_sink_caps</code></em> ()</p></td>
<td class="struct_member_description"><p>Optional.
Allows the subclass to be notified of the actual caps set.</p></td>
<td class="struct_member_annotations"> </td>
</tr>
<tr>
<td class="struct_member_name"><p><em class="structfield"><code><a name="GstBaseParseClass.handle-frame"></a>handle_frame</code></em> ()</p></td>
<td class="struct_member_description"><p>Parses the input data into valid frames as defined by subclass
which should be passed to <a class="link" href="GstBaseParse.html#gst-base-parse-finish-frame" title="gst_base_parse_finish_frame ()"><code class="function">gst_base_parse_finish_frame()</code></a>.
The frame's input buffer is guaranteed writable,
whereas the input frame ownership is held by caller
(so subclass should make a copy if it needs to hang on).
Input buffer (data) is provided by baseclass with as much
metadata set as possible by baseclass according to upstream
information and/or subclass settings,
though subclass may still set buffer timestamp and duration
if desired.</p></td>
<td class="struct_member_annotations"> </td>
</tr>
<tr>
<td class="struct_member_name"><p><em class="structfield"><code><a name="GstBaseParseClass.pre-push-frame"></a>pre_push_frame</code></em> ()</p></td>
<td class="struct_member_description"><p>Optional.
Called just prior to pushing a frame (after any pending
events have been sent) to give subclass a chance to perform
additional actions at this time (e.g. tag sending) or to
decide whether this buffer should be dropped or not
(e.g. custom segment clipping).</p></td>
<td class="struct_member_annotations"> </td>
</tr>
<tr>
<td class="struct_member_name"><p><em class="structfield"><code><a name="GstBaseParseClass.convert"></a>convert</code></em> ()</p></td>
<td class="struct_member_description"><p>Optional.
Convert between formats.</p></td>
<td class="struct_member_annotations"> </td>
</tr>
<tr>
<td class="struct_member_name"><p><em class="structfield"><code><a name="GstBaseParseClass.sink-event"></a>sink_event</code></em> ()</p></td>
<td class="struct_member_description"><p>Optional.
Event handler on the sink pad. This function should chain
up to the parent implementation to let the default handler
run.</p></td>
<td class="struct_member_annotations"> </td>
</tr>
<tr>
<td class="struct_member_name"><p><em class="structfield"><code><a name="GstBaseParseClass.src-event"></a>src_event</code></em> ()</p></td>
<td class="struct_member_description"><p>Optional.
Event handler on the source pad. Should chain up to the
parent to let the default handler run.</p></td>
<td class="struct_member_annotations"> </td>
</tr>
<tr>
<td class="struct_member_name"><p><em class="structfield"><code><a name="GstBaseParseClass.get-sink-caps"></a>get_sink_caps</code></em> ()</p></td>
<td class="struct_member_description"><p>Optional.
Allows the subclass to do its own sink get caps if needed.</p></td>
<td class="struct_member_annotations"> </td>
</tr>
<tr>
<td class="struct_member_name"><p><em class="structfield"><code><a name="GstBaseParseClass.detect"></a>detect</code></em> ()</p></td>
<td class="struct_member_description"><p>Optional.
Called until it doesn't return GST_FLOW_OK anymore for
the first buffers. Can be used by the subclass to detect
the stream format.</p></td>
<td class="struct_member_annotations"> </td>
</tr>
<tr>
<td class="struct_member_name"><p><em class="structfield"><code><a name="GstBaseParseClass.sink-query"></a>sink_query</code></em> ()</p></td>
<td class="struct_member_description"><p>Optional.
Query handler on the sink pad. This function should chain
up to the parent implementation to let the default handler
run (Since 1.2)</p></td>
<td class="struct_member_annotations"> </td>
</tr>
<tr>
<td class="struct_member_name"><p><em class="structfield"><code><a name="GstBaseParseClass.src-query"></a>src_query</code></em> ()</p></td>
<td class="struct_member_description"><p>Optional.
Query handler on the source pad. Should chain up to the
parent to let the default handler run (Since 1.2)</p></td>
<td class="struct_member_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GstBaseParseFrame"></a><h3>GstBaseParseFrame</h3>
<pre class="programlisting">typedef struct {
GstBuffer * buffer;
GstBuffer * out_buffer;
guint flags;
guint64 offset;
gint overhead;
} GstBaseParseFrame;
</pre>
<p>Frame (context) data passed to each frame parsing virtual methods. In
addition to providing the data to be checked for a valid frame or an already
identified frame, it conveys additional metadata or control information
from and to the subclass w.r.t. the particular frame in question (rather
than global parameters). Some of these may apply to each parsing stage, others
only to some a particular one. These parameters are effectively zeroed at start
of each frame's processing, i.e. parsing virtual method invocation sequence.</p>
<div class="refsect3">
<a name="id-1.2.4.3.10.4.5"></a><h4>Members</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="300px" class="struct_members_name">
<col class="struct_members_description">
<col width="200px" class="struct_members_annotations">
</colgroup>
<tbody>
<tr>
<td class="struct_member_name"><p><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstBuffer.html"><span class="type">GstBuffer</span></a> *<em class="structfield"><code><a name="GstBaseParseFrame.buffer"></a>buffer</code></em>;</p></td>
<td class="struct_member_description"><p>input data to be parsed for frames.</p></td>
<td class="struct_member_annotations"> </td>
</tr>
<tr>
<td class="struct_member_name"><p><a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstBuffer.html"><span class="type">GstBuffer</span></a> *<em class="structfield"><code><a name="GstBaseParseFrame.out-buffer"></a>out_buffer</code></em>;</p></td>
<td class="struct_member_description"><p>output data.</p></td>
<td class="struct_member_annotations"> </td>
</tr>
<tr>
<td class="struct_member_name"><p><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#guint"><span class="type">guint</span></a> <em class="structfield"><code><a name="GstBaseParseFrame.flags"></a>flags</code></em>;</p></td>
<td class="struct_member_description"><p>a combination of input and output <a class="link" href="GstBaseParse.html#GstBaseParseFrameFlags" title="enum GstBaseParseFrameFlags"><span class="type">GstBaseParseFrameFlags</span></a> that
convey additional context to subclass or allow subclass to tune
subsequent <a class="link" href="GstBaseParse.html" title="GstBaseParse"><span class="type">GstBaseParse</span></a> actions.</p></td>
<td class="struct_member_annotations"> </td>
</tr>
<tr>
<td class="struct_member_name"><p><span class="type">guint64</span> <em class="structfield"><code><a name="GstBaseParseFrame.offset"></a>offset</code></em>;</p></td>
<td class="struct_member_description"><p>media specific offset of input frame
Note that a converter may have a different one on the frame's buffer.</p></td>
<td class="struct_member_annotations"> </td>
</tr>
<tr>
<td class="struct_member_name"><p><a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gint"><span class="type">gint</span></a> <em class="structfield"><code><a name="GstBaseParseFrame.overhead"></a>overhead</code></em>;</p></td>
<td class="struct_member_description"><p>subclass can set this to indicates the metadata overhead
for the given frame, which is then used to enable more accurate bitrate
computations. If this is -1, it is assumed that this frame should be
skipped in bitrate calculation.</p></td>
<td class="struct_member_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GstBaseParseFrameFlags"></a><h3>enum GstBaseParseFrameFlags</h3>
<p>Flags to be used in a <a class="link" href="GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a>.</p>
<div class="refsect3">
<a name="id-1.2.4.3.10.5.4"></a><h4>Members</h4>
<div class="informaltable"><table width="100%" border="0">
<colgroup>
<col width="300px" class="enum_members_name">
<col class="enum_members_description">
<col width="200px" class="enum_members_annotations">
</colgroup>
<tbody>
<tr>
<td class="enum_member_name"><p><a name="GST-BASE-PARSE-FRAME-FLAG-NONE:CAPS"></a>GST_BASE_PARSE_FRAME_FLAG_NONE</p></td>
<td class="enum_member_description">
<p>no flag</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
<tr>
<td class="enum_member_name"><p><a name="GST-BASE-PARSE-FRAME-FLAG-NEW-FRAME:CAPS"></a>GST_BASE_PARSE_FRAME_FLAG_NEW_FRAME</p></td>
<td class="enum_member_description">
<p>set by baseclass if current frame
is passed for processing to the subclass for the first time
(and not set on subsequent calls with same data).</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
<tr>
<td class="enum_member_name"><p><a name="GST-BASE-PARSE-FRAME-FLAG-NO-FRAME:CAPS"></a>GST_BASE_PARSE_FRAME_FLAG_NO_FRAME</p></td>
<td class="enum_member_description">
<p>set to indicate this buffer should not be
counted as frame, e.g. if this frame is dependent on a previous one.
As it is not counted as a frame, bitrate increases but frame to time
conversions are maintained.</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
<tr>
<td class="enum_member_name"><p><a name="GST-BASE-PARSE-FRAME-FLAG-CLIP:CAPS"></a>GST_BASE_PARSE_FRAME_FLAG_CLIP</p></td>
<td class="enum_member_description">
<p><em class="parameter"><code>pre_push_frame</code></em>
can set this to indicate
that regular segment clipping can still be performed (as opposed to
any custom one having been done).</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
<tr>
<td class="enum_member_name"><p><a name="GST-BASE-PARSE-FRAME-FLAG-DROP:CAPS"></a>GST_BASE_PARSE_FRAME_FLAG_DROP</p></td>
<td class="enum_member_description">
<p>indicates to <em class="parameter"><code>finish_frame</code></em>
that the
the frame should be dropped (and might be handled internally by subclass)</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
<tr>
<td class="enum_member_name"><p><a name="GST-BASE-PARSE-FRAME-FLAG-QUEUE:CAPS"></a>GST_BASE_PARSE_FRAME_FLAG_QUEUE</p></td>
<td class="enum_member_description">
<p>indicates to <em class="parameter"><code>finish_frame</code></em>
that the
the frame should be queued for now and processed fully later
when the first non-queued frame is finished</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="GST-BASE-PARSE-FLOW-DROPPED:CAPS"></a><h3>GST_BASE_PARSE_FLOW_DROPPED</h3>
<pre class="programlisting">#define GST_BASE_PARSE_FLOW_DROPPED GST_FLOW_CUSTOM_SUCCESS
</pre>
<p>A <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstPad.html#GstFlowReturn"><span class="type">GstFlowReturn</span></a> that can be returned from parse_frame to
indicate that no output buffer was generated, or from pre_push_frame to
to forego pushing buffer.</p>
</div>
</div>
<div class="refsect1">
<a name="GstBaseParse.property-details"></a><h2>Property Details</h2>
<div class="refsect2">
<a name="GstBaseParse--disable-passthrough"></a><h3>The <code class="literal">“disable-passthrough”</code> property</h3>
<pre class="programlisting"> “disable-passthrough” <a href="https://developer.gnome.org/glib/unstable/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></pre>
<p>If set to <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a>, baseparse will unconditionally force parsing of the
incoming data. This can be required in the rare cases where the incoming
side-data (caps, pts, dts, ...) is not trusted by the user and wants to
force validation and parsing of the incoming data.
If set to <a href="https://developer.gnome.org/glib/unstable/glib-Standard-Macros.html#FALSE:CAPS"><code class="literal">FALSE</code></a>, decision of whether to parse the data or not is up to
the implementation (standard behaviour).</p>
<p>Flags: Read / Write</p>
<p>Default value: FALSE</p>
</div>
</div>
<div class="refsect1">
<a name="GstBaseParse.see-also"></a><h2>See Also</h2>
<p><a class="link" href="GstBaseTransform.html" title="GstBaseTransform"><span class="type">GstBaseTransform</span></a></p>
</div>
</div>
<div class="footer">
<hr>Generated by GTK-Doc V1.24</div>
</body>
</html>