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| <a href="#gstreamer-libs-GstBaseParse.description" class="shortcut">Description</a> |
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| <a name="gstreamer-libs-GstBaseParse"></a><div class="titlepage"></div> |
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| <h2><span class="refentrytitle"><a name="gstreamer-libs-GstBaseParse.top_of_page"></a>GstBaseParse</span></h2> |
| <p>GstBaseParse — Base class for stream parsers</p> |
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| <div class="refsynopsisdiv"> |
| <a name="gstreamer-libs-GstBaseParse.synopsis"></a><h2>Synopsis</h2> |
| <pre class="synopsis"> |
| #include <gst/base/gstbaseparse.h> |
| |
| struct <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse">GstBaseParse</a>; |
| struct <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParseClass" title="struct GstBaseParseClass">GstBaseParseClass</a>; |
| <span class="returnvalue">void</span> <a class="link" href="gstreamer-libs-GstBaseParse.html#gst-base-parse-set-duration" title="gst_base_parse_set_duration ()">gst_base_parse_set_duration</a> (<em class="parameter"><code><a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>, |
| <em class="parameter"><code><a href="../gstreamer-0.11/gstreamer-GstFormat.html#GstFormat"><span class="type">GstFormat</span></a> fmt</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gint64"><span class="type">gint64</span></a> duration</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gint"><span class="type">gint</span></a> interval</code></em>); |
| <span class="returnvalue">void</span> <a class="link" href="gstreamer-libs-GstBaseParse.html#gst-base-parse-set-average-bitrate" title="gst_base_parse_set_average_bitrate ()">gst_base_parse_set_average_bitrate</a> (<em class="parameter"><code><a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#guint"><span class="type">guint</span></a> bitrate</code></em>); |
| <span class="returnvalue">void</span> <a class="link" href="gstreamer-libs-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> (<em class="parameter"><code><a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#guint"><span class="type">guint</span></a> min_size</code></em>); |
| <span class="returnvalue">void</span> <a class="link" href="gstreamer-libs-GstBaseParse.html#gst-base-parse-set-passthrough" title="gst_base_parse_set_passthrough ()">gst_base_parse_set_passthrough</a> (<em class="parameter"><code><a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</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> passthrough</code></em>); |
| <span class="returnvalue">void</span> <a class="link" href="gstreamer-libs-GstBaseParse.html#gst-base-parse-set-syncable" title="gst_base_parse_set_syncable ()">gst_base_parse_set_syncable</a> (<em class="parameter"><code><a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</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> syncable</code></em>); |
| <span class="returnvalue">void</span> <a class="link" href="gstreamer-libs-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> (<em class="parameter"><code><a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</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> has_timing</code></em>); |
| <span class="returnvalue">void</span> <a class="link" href="gstreamer-libs-GstBaseParse.html#gst-base-parse-set-frame-rate" title="gst_base_parse_set_frame_rate ()">gst_base_parse_set_frame_rate</a> (<em class="parameter"><code><a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#guint"><span class="type">guint</span></a> fps_num</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#guint"><span class="type">guint</span></a> fps_den</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#guint"><span class="type">guint</span></a> lead_in</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#guint"><span class="type">guint</span></a> lead_out</code></em>); |
| <span class="returnvalue">void</span> <a class="link" href="gstreamer-libs-GstBaseParse.html#gst-base-parse-set-latency" title="gst_base_parse_set_latency ()">gst_base_parse_set_latency</a> (<em class="parameter"><code><a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>, |
| <em class="parameter"><code><a href="../gstreamer-0.11/GstClock.html#GstClockTime"><span class="type">GstClockTime</span></a> min_latency</code></em>, |
| <em class="parameter"><code><a href="../gstreamer-0.11/GstClock.html#GstClockTime"><span class="type">GstClockTime</span></a> max_latency</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-libs-GstBaseParse.html#gst-base-parse-convert-default" title="gst_base_parse_convert_default ()">gst_base_parse_convert_default</a> (<em class="parameter"><code><a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>, |
| <em class="parameter"><code><a href="../gstreamer-0.11/gstreamer-GstFormat.html#GstFormat"><span class="type">GstFormat</span></a> src_format</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gint64"><span class="type">gint64</span></a> src_value</code></em>, |
| <em class="parameter"><code><a href="../gstreamer-0.11/gstreamer-GstFormat.html#GstFormat"><span class="type">GstFormat</span></a> dest_format</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gint64"><span class="type">gint64</span></a> *dest_value</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-libs-GstBaseParse.html#gst-base-parse-add-index-entry" title="gst_base_parse_add_index_entry ()">gst_base_parse_add_index_entry</a> (<em class="parameter"><code><a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#guint64"><span class="type">guint64</span></a> offset</code></em>, |
| <em class="parameter"><code><a href="../gstreamer-0.11/GstClock.html#GstClockTime"><span class="type">GstClockTime</span></a> ts</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> key</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> force</code></em>); |
| <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame">GstBaseParseFrame</a>; |
| enum <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParseFrameFlags" title="enum GstBaseParseFrameFlags">GstBaseParseFrameFlags</a>; |
| <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="returnvalue">GstBaseParseFrame</span></a> * <a class="link" href="gstreamer-libs-GstBaseParse.html#gst-base-parse-frame-new" title="gst_base_parse_frame_new ()">gst_base_parse_frame_new</a> (<em class="parameter"><code><a href="../gstreamer-0.11/gstreamer-GstBuffer.html#GstBuffer"><span class="type">GstBuffer</span></a> *buffer</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParseFrameFlags" title="enum GstBaseParseFrameFlags"><span class="type">GstBaseParseFrameFlags</span></a> flags</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gint"><span class="type">gint</span></a> overhead</code></em>); |
| <span class="returnvalue">void</span> <a class="link" href="gstreamer-libs-GstBaseParse.html#gst-base-parse-frame-init" title="gst_base_parse_frame_init ()">gst_base_parse_frame_init</a> (<em class="parameter"><code><a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a> *frame</code></em>); |
| <span class="returnvalue">void</span> <a class="link" href="gstreamer-libs-GstBaseParse.html#gst-base-parse-frame-free" title="gst_base_parse_frame_free ()">gst_base_parse_frame_free</a> (<em class="parameter"><code><a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a> *frame</code></em>); |
| <a href="../gstreamer-0.11/GstPad.html#GstFlowReturn"><span class="returnvalue">GstFlowReturn</span></a> <a class="link" href="gstreamer-libs-GstBaseParse.html#gst-base-parse-push-frame" title="gst_base_parse_push_frame ()">gst_base_parse_push_frame</a> (<em class="parameter"><code><a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a> *frame</code></em>); |
| #define <a class="link" href="gstreamer-libs-GstBaseParse.html#GST-BASE-PARSE-DRAINING:CAPS" title="GST_BASE_PARSE_DRAINING()">GST_BASE_PARSE_DRAINING</a> (parse) |
| #define <a class="link" href="gstreamer-libs-GstBaseParse.html#GST-BASE-PARSE-FLAG-DRAINING:CAPS" title="GST_BASE_PARSE_FLAG_DRAINING">GST_BASE_PARSE_FLAG_DRAINING</a> |
| #define <a class="link" href="gstreamer-libs-GstBaseParse.html#GST-BASE-PARSE-FLAG-LOST-SYNC:CAPS" title="GST_BASE_PARSE_FLAG_LOST_SYNC">GST_BASE_PARSE_FLAG_LOST_SYNC</a> |
| #define <a class="link" href="gstreamer-libs-GstBaseParse.html#GST-BASE-PARSE-FLOW-DROPPED:CAPS" title="GST_BASE_PARSE_FLOW_DROPPED">GST_BASE_PARSE_FLOW_DROPPED</a> |
| #define <a class="link" href="gstreamer-libs-GstBaseParse.html#GST-BASE-PARSE-FLOW-QUEUED:CAPS" title="GST_BASE_PARSE_FLOW_QUEUED">GST_BASE_PARSE_FLOW_QUEUED</a> |
| #define <a class="link" href="gstreamer-libs-GstBaseParse.html#GST-BASE-PARSE-LOST-SYNC:CAPS" title="GST_BASE_PARSE_LOST_SYNC()">GST_BASE_PARSE_LOST_SYNC</a> (parse) |
| #define <a class="link" href="gstreamer-libs-GstBaseParse.html#GST-BASE-PARSE-SINK-PAD:CAPS" title="GST_BASE_PARSE_SINK_PAD()">GST_BASE_PARSE_SINK_PAD</a> (obj) |
| #define <a class="link" href="gstreamer-libs-GstBaseParse.html#GST-BASE-PARSE-SRC-PAD:CAPS" title="GST_BASE_PARSE_SRC_PAD()">GST_BASE_PARSE_SRC_PAD</a> (obj) |
| </pre> |
| </div> |
| <div class="refsect1"> |
| <a name="gstreamer-libs-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" 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 (NEWSEGMENT/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> |
| </p> |
| <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" type="disc"> |
| <li class="listitem"><p> |
| GstBaseParse class calls <em class="parameter"><code>set_sink_caps</code></em> to inform the subclass about |
| incoming sinkpad caps. Subclass should set the srcpad caps accordingly. |
| </p></li> |
| <li class="listitem"><p> |
| GstBaseParse 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> |
| At least at this point subclass needs to tell the GstBaseParse class |
| how big data chunks it wants to receive (min_frame_size). It can do |
| this with <a class="link" href="gstreamer-libs-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> |
| GstBaseParse 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" type="disc"> |
| <li class="listitem"><p> |
| GstBaseParse 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>check_valid_frame</code></em>. Subclass checks the contents and returns TRUE |
| if the buffer contains a valid frame. It also needs to set the |
| <em class="parameter"><code>framesize</code></em> according to the detected frame size. If buffer didn't |
| contain a valid frame, this call must return FALSE and optionally |
| set the <em class="parameter"><code>skipsize</code></em> value to inform base class that how many bytes |
| it needs to skip in order to find a valid frame. <em class="parameter"><code>framesize</code></em> can always |
| indicate a new minimum for current frame parsing. Indicating G_MAXUINT |
| for requested amount means subclass simply needs best available |
| subsequent data. 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. The passed buffer |
| is read-only. 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> |
| After valid frame is found, it will be passed again to subclass with |
| <em class="parameter"><code>parse_frame</code></em> call. Now subclass is responsible for parsing the |
| frame contents and setting the caps, and buffer metadata (e.g. |
| buffer timestamp and duration, or keyframe if applicable). |
| (although the latter can also be done by GstBaseParse 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></li> |
| <li class="listitem"><p> |
| Finally the buffer can be pushed downstream and the parsing loop starts |
| over again. Just prior to actually pushing the buffer in question, |
| it is passed to <em class="parameter"><code>pre_push_buffer</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 GstBaseParseClass 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" type="disc"><li class="listitem"><p> |
| GstBaseParse 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> |
| </p> |
| <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="../gstreamer-0.11/gstreamer-GstFormat.html#GST-FORMAT-DEFAULT:CAPS"><span class="type">GST_FORMAT_DEFAULT</span></a> as a meaning of frames. So, |
| subclass conversion routine needs to know that conversion from |
| <a href="../gstreamer-0.11/gstreamer-GstFormat.html#GST-FORMAT-TIME:CAPS"><span class="type">GST_FORMAT_TIME</span></a> to <a href="../gstreamer-0.11/gstreamer-GstFormat.html#GST-FORMAT-DEFAULT:CAPS"><span class="type">GST_FORMAT_DEFAULT</span></a> must return the |
| frame number that can be found from the given byte position. |
| </p> |
| <p> |
| GstBaseParse 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" 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="gstreamer-libs-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>check_valid_frame</code></em> |
| and tell if they contain a valid frame |
| </p></li> |
| <li class="listitem"><p> |
| Set the caps and timestamp to frame that is passed to subclass with |
| <em class="parameter"><code>parse_frame</code></em> function. |
| </p></li> |
| <li class="listitem"><p>Provide conversion functions</p></li> |
| <li class="listitem"><p> |
| Update the duration information with <a class="link" href="gstreamer-libs-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="gstreamer-libs-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="gstreamer-libs-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="gstreamer-libs-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="gstreamer-libs-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 GstBaseParse 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 GstBaseParse with an estimated |
| bitrate. A default <em class="parameter"><code>convert</code></em> (used if not overriden) 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> |
| <p> |
| </p> |
| </div> |
| <div class="refsect1"> |
| <a name="gstreamer-libs-GstBaseParse.details"></a><h2>Details</h2> |
| <div class="refsect2"> |
| <a name="GstBaseParse"></a><h3>struct GstBaseParse</h3> |
| <pre class="programlisting">struct GstBaseParse { |
| GstElement element; |
| }; |
| </pre> |
| <p> |
| The opaque <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> data structure. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody><tr> |
| <td><p><span class="term"><a href="../gstreamer-0.11/GstElement.html"><span class="type">GstElement</span></a> <em class="structfield"><code><a name="GstBaseParse.element"></a>element</code></em>;</span></p></td> |
| <td>the parent element.</td> |
| </tr></tbody> |
| </table></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); |
| |
| gboolean (*check_valid_frame) (GstBaseParse * parse, |
| GstBaseParseFrame * frame, |
| guint * framesize, |
| gint * skipsize); |
| |
| GstFlowReturn (*parse_frame) (GstBaseParse * parse, |
| GstBaseParseFrame * frame); |
| |
| 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 (*event) (GstBaseParse * parse, |
| GstEvent * event); |
| |
| gboolean (*src_event) (GstBaseParse * parse, |
| GstEvent * event); |
| }; |
| </pre> |
| <p> |
| Subclasses can override any of the available virtual methods or not, as |
| needed. At minimum <em class="parameter"><code>check_valid_frame</code></em> and <em class="parameter"><code>parse_frame</code></em> needs to be |
| overridden. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><a href="../gstreamer-0.11/GstElement.html#GstElementClass"><span class="type">GstElementClass</span></a> <em class="structfield"><code><a name="GstBaseParseClass.parent-class"></a>parent_class</code></em>;</span></p></td> |
| <td>the parent class</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="structfield"><code><a name="GstBaseParseClass.start"></a>start</code></em> ()</span></p></td> |
| <td>Optional. |
| Called when the element starts processing. |
| Allows opening external resources.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="structfield"><code><a name="GstBaseParseClass.stop"></a>stop</code></em> ()</span></p></td> |
| <td>Optional. |
| Called when the element stops processing. |
| Allows closing external resources.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="structfield"><code><a name="GstBaseParseClass.set-sink-caps"></a>set_sink_caps</code></em> ()</span></p></td> |
| <td>allows the subclass to be notified of the actual caps set.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="structfield"><code><a name="GstBaseParseClass.check-valid-frame"></a>check_valid_frame</code></em> ()</span></p></td> |
| <td>Check if the given piece of data contains a valid |
| frame.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="structfield"><code><a name="GstBaseParseClass.parse-frame"></a>parse_frame</code></em> ()</span></p></td> |
| <td>Parse the already checked frame. Subclass need to |
| set the buffer timestamp, duration, caps and possibly |
| other necessary metadata. This is called with srcpad's |
| STREAM_LOCK held.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="structfield"><code><a name="GstBaseParseClass.pre-push-frame"></a>pre_push_frame</code></em> ()</span></p></td> |
| <td>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).</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="structfield"><code><a name="GstBaseParseClass.convert"></a>convert</code></em> ()</span></p></td> |
| <td>Optional. |
| Convert between formats.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="structfield"><code><a name="GstBaseParseClass.event"></a>event</code></em> ()</span></p></td> |
| <td>Optional. |
| Event handler on the sink pad. This function should return |
| TRUE if the event was handled and can be dropped.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="structfield"><code><a name="GstBaseParseClass.src-event"></a>src_event</code></em> ()</span></p></td> |
| <td>Optional. |
| Event handler on the source pad. Should return TRUE |
| if the event was handled and can be dropped.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <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="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>, |
| <em class="parameter"><code><a href="../gstreamer-0.11/gstreamer-GstFormat.html#GstFormat"><span class="type">GstFormat</span></a> fmt</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gint64"><span class="type">gint64</span></a> duration</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/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="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>parse</code></em> :</span></p></td> |
| <td> |
| <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a>.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>fmt</code></em> :</span></p></td> |
| <td> |
| <a href="../gstreamer-0.11/gstreamer-GstFormat.html#GstFormat"><span class="type">GstFormat</span></a>.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>duration</code></em> :</span></p></td> |
| <td>duration value.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>interval</code></em> :</span></p></td> |
| <td>how often to update the duration estimate based on bitrate, or 0.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 0.10.33</p> |
| </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="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/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="gstreamer-libs-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="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>parse</code></em> :</span></p></td> |
| <td> |
| <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a>.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>bitrate</code></em> :</span></p></td> |
| <td>average bitrate in bits/second</td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 0.10.33</p> |
| </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="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/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="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>parse</code></em> :</span></p></td> |
| <td> |
| <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a>.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>min_size</code></em> :</span></p></td> |
| <td>Minimum size of the data that this base class should give to |
| subclass.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 0.10.33</p> |
| </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="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</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> 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_buffer</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_buffer</code></em>. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>parse</code></em> :</span></p></td> |
| <td>a <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>passthrough</code></em> :</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 parser should run in passthrough mode</td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 0.10.33</p> |
| </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="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</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> 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="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>parse</code></em> :</span></p></td> |
| <td>a <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>syncable</code></em> :</span></p></td> |
| <td>set if frame starts can be identified</td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 0.10.33</p> |
| </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="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</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> 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="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>parse</code></em> :</span></p></td> |
| <td>a <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>has_timing</code></em> :</span></p></td> |
| <td>whether frames carry timing information</td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 0.10.33</p> |
| </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="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#guint"><span class="type">guint</span></a> fps_num</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#guint"><span class="type">guint</span></a> fps_den</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#guint"><span class="type">guint</span></a> lead_in</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/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="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>parse</code></em> :</span></p></td> |
| <td>the <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> to set</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>fps_num</code></em> :</span></p></td> |
| <td>frames per second (numerator).</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>fps_den</code></em> :</span></p></td> |
| <td>frames per second (denominator).</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>lead_in</code></em> :</span></p></td> |
| <td>frames needed before a segment for subsequent decode</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>lead_out</code></em> :</span></p></td> |
| <td>frames needed after a segment</td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 0.10.33</p> |
| </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="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>, |
| <em class="parameter"><code><a href="../gstreamer-0.11/GstClock.html#GstClockTime"><span class="type">GstClockTime</span></a> min_latency</code></em>, |
| <em class="parameter"><code><a href="../gstreamer-0.11/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="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>parse</code></em> :</span></p></td> |
| <td>a <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>min_latency</code></em> :</span></p></td> |
| <td>minimum parse latency</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>max_latency</code></em> :</span></p></td> |
| <td>maximum parse latency</td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 0.10.34</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="http://library.gnome.org/devel/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="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>, |
| <em class="parameter"><code><a href="../gstreamer-0.11/gstreamer-GstFormat.html#GstFormat"><span class="type">GstFormat</span></a> src_format</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gint64"><span class="type">gint64</span></a> src_value</code></em>, |
| <em class="parameter"><code><a href="../gstreamer-0.11/gstreamer-GstFormat.html#GstFormat"><span class="type">GstFormat</span></a> dest_format</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gint64"><span class="type">gint64</span></a> *dest_value</code></em>);</pre> |
| <p> |
| Default implementation of "convert" vmethod in <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> class. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>parse</code></em> :</span></p></td> |
| <td> |
| <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a>.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>src_format</code></em> :</span></p></td> |
| <td> |
| <a href="../gstreamer-0.11/gstreamer-GstFormat.html#GstFormat"><span class="type">GstFormat</span></a> describing the source format.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>src_value</code></em> :</span></p></td> |
| <td>Source value to be converted.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>dest_format</code></em> :</span></p></td> |
| <td> |
| <a href="../gstreamer-0.11/gstreamer-GstFormat.html#GstFormat"><span class="type">GstFormat</span></a> defining the converted format.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>dest_value</code></em> :</span></p></td> |
| <td>Pointer where the conversion result will be put.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>TRUE if conversion was successful.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 0.10.33</p> |
| </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="http://library.gnome.org/devel/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="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#guint64"><span class="type">guint64</span></a> offset</code></em>, |
| <em class="parameter"><code><a href="../gstreamer-0.11/GstClock.html#GstClockTime"><span class="type">GstClockTime</span></a> ts</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> key</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> 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="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>parse</code></em> :</span></p></td> |
| <td> |
| <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a>.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>offset</code></em> :</span></p></td> |
| <td>offset of entry</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>ts</code></em> :</span></p></td> |
| <td>timestamp associated with offset</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>key</code></em> :</span></p></td> |
| <td>whether entry refers to keyframe</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>force</code></em> :</span></p></td> |
| <td>add entry disregarding sanity checks</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-Basic-Types.html#gboolean"><span class="type">gboolean</span></a> indicating whether entry was added</td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 0.10.33</p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstBaseParseFrame"></a><h3>GstBaseParseFrame</h3> |
| <pre class="programlisting">typedef struct { |
| GstBuffer * buffer; |
| guint flags; |
| 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="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><a href="../gstreamer-0.11/gstreamer-GstBuffer.html#GstBuffer"><span class="type">GstBuffer</span></a> *<em class="structfield"><code><a name="GstBaseParseFrame.buffer"></a>buffer</code></em>;</span></p></td> |
| <td>data to check for valid frame or parsed frame. |
| Subclass is allowed to replace this buffer.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><a href="http://library.gnome.org/devel/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>;</span></p></td> |
| <td>a combination of input and output <a class="link" href="gstreamer-libs-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="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> actions.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><a href="http://library.gnome.org/devel/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>;</span></p></td> |
| <td>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.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 0.10.33</p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstBaseParseFrameFlags"></a><h3>enum GstBaseParseFrameFlags</h3> |
| <pre class="programlisting">typedef enum { |
| GST_BASE_PARSE_FRAME_FLAG_NONE = 0, |
| GST_BASE_PARSE_FRAME_FLAG_NO_FRAME = (1 << 0), |
| GST_BASE_PARSE_FRAME_FLAG_CLIP = (1 << 1) |
| } GstBaseParseFrameFlags; |
| </pre> |
| <p> |
| Flags to be used in a <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a>. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><a name="GST-BASE-PARSE-FRAME-FLAG-NONE:CAPS"></a><span class="term"><code class="literal">GST_BASE_PARSE_FRAME_FLAG_NONE</code></span></p></td> |
| <td>no flag |
| </td> |
| </tr> |
| <tr> |
| <td><p><a name="GST-BASE-PARSE-FRAME-FLAG-NO-FRAME:CAPS"></a><span class="term"><code class="literal">GST_BASE_PARSE_FRAME_FLAG_NO_FRAME</code></span></p></td> |
| <td>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. |
| </td> |
| </tr> |
| <tr> |
| <td><p><a name="GST-BASE-PARSE-FRAME-FLAG-CLIP:CAPS"></a><span class="term"><code class="literal">GST_BASE_PARSE_FRAME_FLAG_CLIP</code></span></p></td> |
| <td> |
| <em class="parameter"><code>pre_push_buffer</code></em> can set this to indicate |
| that regular segment clipping can still be performed (as opposed to |
| any custom one having been done). |
| </td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 0.10.33</p> |
| </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="gstreamer-libs-GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="returnvalue">GstBaseParseFrame</span></a> * gst_base_parse_frame_new (<em class="parameter"><code><a href="../gstreamer-0.11/gstreamer-GstBuffer.html#GstBuffer"><span class="type">GstBuffer</span></a> *buffer</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParseFrameFlags" title="enum GstBaseParseFrameFlags"><span class="type">GstBaseParseFrameFlags</span></a> flags</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/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="gstreamer-libs-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="gstreamer-libs-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="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>buffer</code></em> :</span></p></td> |
| <td>a <a href="../gstreamer-0.11/gstreamer-GstBuffer.html#GstBuffer"><span class="type">GstBuffer</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>flags</code></em> :</span></p></td> |
| <td>the flags</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>overhead</code></em> :</span></p></td> |
| <td>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.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>a newly-allocated <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a>. Free with |
| <a class="link" href="gstreamer-libs-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, unless you gave |
| away ownership to <a class="link" href="gstreamer-libs-GstBaseParse.html#gst-base-parse-push-frame" title="gst_base_parse_push_frame ()"><code class="function">gst_base_parse_push_frame()</code></a>.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 0.10.33</p> |
| </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="gstreamer-libs-GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a> *frame</code></em>);</pre> |
| <p> |
| Sets a <a class="link" href="gstreamer-libs-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="gstreamer-libs-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="gstreamer-libs-GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a> |
| allocated on the stack. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody><tr> |
| <td><p><span class="term"><em class="parameter"><code>frame</code></em> :</span></p></td> |
| <td> |
| <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a>.</td> |
| </tr></tbody> |
| </table></div> |
| <p class="since">Since 0.10.33</p> |
| </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="gstreamer-libs-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="../gstreamer-0.11/GstPad.html#GstFlowReturn"><span class="returnvalue">GstFlowReturn</span></a> gst_base_parse_push_frame (<em class="parameter"><code><a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a> *parse</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a> *frame</code></em>);</pre> |
| <p> |
| Pushes the frame downstream, sends any pending events and |
| does some timestamp and segment handling. Takes ownership |
| of <em class="parameter"><code>frame</code></em> and will clear it (if it was initialised with |
| <a class="link" href="gstreamer-libs-GstBaseParse.html#gst-base-parse-frame-init" title="gst_base_parse_frame_init ()"><code class="function">gst_base_parse_frame_init()</code></a>) or free it. |
| </p> |
| <p> |
| This must be called with sinkpad STREAM_LOCK held. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>parse</code></em> :</span></p></td> |
| <td> |
| <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParse" title="struct GstBaseParse"><span class="type">GstBaseParse</span></a>.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>frame</code></em> :</span></p></td> |
| <td>a <a class="link" href="gstreamer-libs-GstBaseParse.html#GstBaseParseFrame" title="GstBaseParseFrame"><span class="type">GstBaseParseFrame</span></a>. <span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td><a href="../gstreamer-0.11/GstPad.html#GstFlowReturn"><span class="type">GstFlowReturn</span></a></td> |
| </tr> |
| </tbody> |
| </table></div> |
| <p class="since">Since 0.10.33</p> |
| </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)->flags & 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="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody><tr> |
| <td><p><span class="term"><em class="parameter"><code>parse</code></em> :</span></p></td> |
| <td>base parse instance</td> |
| </tr></tbody> |
| </table></div> |
| <p class="since">Since 0.10.33</p> |
| </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 << 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 << 0) |
| </pre> |
| </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="../gstreamer-0.11/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_buffer to |
| to forego pushing buffer. |
| </p> |
| <p class="since">Since 0.10.33</p> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GST-BASE-PARSE-FLOW-QUEUED:CAPS"></a><h3>GST_BASE_PARSE_FLOW_QUEUED</h3> |
| <pre class="programlisting">#define GST_BASE_PARSE_FLOW_QUEUED GST_FLOW_CUSTOM_SUCCESS_1 |
| </pre> |
| <p> |
| A <a href="../gstreamer-0.11/GstPad.html#GstFlowReturn"><span class="type">GstFlowReturn</span></a> that can be returned from parse frame to indicate that |
| the buffer will be queued to be pushed when the next OK |
| </p> |
| <p class="since">Since 0.10.33</p> |
| </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)->flags & GST_BASE_PARSE_FLAG_LOST_SYNC)) |
| </pre> |
| <p> |
| Obtains current sync status. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody><tr> |
| <td><p><span class="term"><em class="parameter"><code>parse</code></em> :</span></p></td> |
| <td>base parse instance</td> |
| </tr></tbody> |
| </table></div> |
| <p class="since">Since 0.10.33</p> |
| </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)->sinkpad) |
| </pre> |
| <p> |
| Gives the pointer to the sink <a href="../gstreamer-0.11/GstPad.html"><span class="type">GstPad</span></a> object of the element. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody><tr> |
| <td><p><span class="term"><em class="parameter"><code>obj</code></em> :</span></p></td> |
| <td>base parse instance</td> |
| </tr></tbody> |
| </table></div> |
| <p class="since">Since 0.10.33</p> |
| </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)->srcpad) |
| </pre> |
| <p> |
| Gives the pointer to the source <a href="../gstreamer-0.11/GstPad.html"><span class="type">GstPad</span></a> object of the element. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody><tr> |
| <td><p><span class="term"><em class="parameter"><code>obj</code></em> :</span></p></td> |
| <td>base parse instance</td> |
| </tr></tbody> |
| </table></div> |
| <p class="since">Since 0.10.33</p> |
| </div> |
| </div> |
| <div class="refsect1"> |
| <a name="gstreamer-libs-GstBaseParse.see-also"></a><h2>See Also</h2> |
| <a class="link" href="GstBaseTransform.html" title="GstBaseTransform"><span class="type">GstBaseTransform</span></a> |
| </div> |
| </div> |
| <div class="footer"> |
| <hr> |
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