MCL/sf/mw/gstreamer: comparison gstreamer

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--1:000000000000
+:0e761a78d257
+/* GStreamer
+* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
+*                    2000 Wim Taymans <wim.taymans@chello.be>
+*                    2005 Wim Taymans <wim@fluendo.com>
+*
+* gstevent.c: GstEvent subsystem
+*
+* This library is free software; you can redistribute it and/or
+* modify it under the terms of the GNU Library General Public
+* License as published by the Free Software Foundation; either
+* version 2 of the License, or (at your option) any later version.
+*
+* This library is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+* Library General Public License for more details.
+*
+* You should have received a copy of the GNU Library General Public
+* License along with this library; if not, write to the
+* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+* Boston, MA 02111-1307, USA.
+*/
+/**
+* SECTION:gstevent
+* @short_description: Structure describing events that are passed up and down
+*                     a pipeline
+* @see_also: #GstPad, #GstElement
+*
+* The event class provides factory methods to construct and functions query
+* (parse) events.
+*
+* Events are usually created with gst_event_new_*() which takes event-type
+* specific parameters as arguments.
+* To send an event application will usually use gst_element_send_event() and
+* elements will use gst_pad_send_event() or gst_pad_push_event().
+* The event should be unreffed with gst_event_unref() if it has not been sent.
+*
+* Events that have been received can be parsed with their respective
+* gst_event_parse_*() functions. It is valid to pass %NULL for unwanted details.
+*
+* Events are passed between elements in parallel to the data stream. Some events
+* are serialized with buffers, others are not. Some events only travel downstream,
+* others only upstream. Some events can travel both upstream and downstream.
+*
+* The events are used to signal special conditions in the datastream such as
+* EOS (end of stream) or the start of a new stream-segment.
+* Events are also used to flush the pipeline of any pending data.
+*
+* Most of the event API is used inside plugins. Applications usually only
+* construct and use seek events.
+* To do that gst_event_new_seek() is used to create a seek event. It takes
+* the needed parameters to specity seeking time and mode.
+* <example>
+* <title>performing a seek on a pipeline</title>
+*   <programlisting>
+*   GstEvent *event;
+*   gboolean result;
+*   ...
+*   // construct a seek event to play the media from second 2 to 5, flush
+*   // the pipeline to decrease latency.
+*   event = gst_event_new_seek (1.0,
+*      GST_FORMAT_TIME,
+*      GST_SEEK_FLAG_FLUSH,
+*      GST_SEEK_TYPE_SET, 2 * GST_SECOND,
+*      GST_SEEK_TYPE_SET, 5 * GST_SECOND);
+*   ...
+*   result = gst_element_send_event (pipeline, event);
+*   if (!result)
+*     g_warning ("seek failed");
+*   ...
+*   </programlisting>
+* </example>
+*
+* Last reviewed on 2006-09-6 (0.10.10)
+*/
+#include "gst_private.h"
+#include <string.h>             /* memcpy */
+#include "gstinfo.h"
+#include "gstevent.h"
+#include "gstenumtypes.h"
+#include "gstutils.h"
+static void gst_event_init (GTypeInstance * instance, gpointer g_class);
+static void gst_event_class_init (gpointer g_class, gpointer class_data);
+static void gst_event_finalize (GstEvent * event);
+static GstEvent *_gst_event_copy (GstEvent * event);
+static GstMiniObjectClass *parent_class = NULL;
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+void
+_gst_event_initialize (void)
+{
+g_type_class_ref (gst_event_get_type ());
+g_type_class_ref (gst_seek_flags_get_type ());
+g_type_class_ref (gst_seek_type_get_type ());
+}
+typedef struct
+{
+const gint type;
+const gchar *name;
+GQuark quark;
+} GstEventQuarks;
+static GstEventQuarks event_quarks[] = {
+{GST_EVENT_UNKNOWN, "unknown", 0},
+{GST_EVENT_FLUSH_START, "flush-start", 0},
+{GST_EVENT_FLUSH_STOP, "flush-stop", 0},
+{GST_EVENT_EOS, "eos", 0},
+{GST_EVENT_NEWSEGMENT, "newsegment", 0},
+{GST_EVENT_TAG, "tag", 0},
+{GST_EVENT_BUFFERSIZE, "buffersize", 0},
+{GST_EVENT_QOS, "qos", 0},
+{GST_EVENT_SEEK, "seek", 0},
+{GST_EVENT_NAVIGATION, "navigation", 0},
+{GST_EVENT_LATENCY, "latency", 0},
+{GST_EVENT_CUSTOM_UPSTREAM, "custom-upstream", 0},
+{GST_EVENT_CUSTOM_DOWNSTREAM, "custom-downstream", 0},
+{GST_EVENT_CUSTOM_DOWNSTREAM_OOB, "custom-downstream-oob", 0},
+{GST_EVENT_CUSTOM_BOTH, "custom-both", 0},
+{GST_EVENT_CUSTOM_BOTH_OOB, "custom-both-oob", 0},
+{0, NULL, 0}
+};
+/**
+* gst_event_type_get_name:
+* @type: the event type
+*
+* Get a printable name for the given event type. Do not modify or free.
+*
+* Returns: a reference to the static name of the event.
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+const gchar *
+gst_event_type_get_name (GstEventType type)
+{
+gint i;
+for (i = 0; event_quarks[i].name; i++) {
+if (type == event_quarks[i].type)
+return event_quarks[i].name;
+}
+return "unknown";
+}
+/**
+* gst_event_type_to_quark:
+* @type: the event type
+*
+* Get the unique quark for the given event type.
+*
+* Returns: the quark associated with the event type
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+GQuark
+gst_event_type_to_quark (GstEventType type)
+{
+gint i;
+for (i = 0; event_quarks[i].name; i++) {
+if (type == event_quarks[i].type)
+return event_quarks[i].quark;
+}
+return 0;
+}
+/**
+* gst_event_type_get_flags:
+* @type: a #GstEventType
+*
+* Gets the #GstEventTypeFlags associated with @type.
+*
+* Returns: a #GstEventTypeFlags.
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+GstEventTypeFlags
+gst_event_type_get_flags (GstEventType type)
+{
+GstEventTypeFlags ret;
+ret = type & ((1 << GST_EVENT_TYPE_SHIFT) - 1);
+return ret;
+}
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+GType
+gst_event_get_type (void)
+{
+static GType _gst_event_type = 0;
+int i;
+if (G_UNLIKELY (_gst_event_type == 0)) {
+static const GTypeInfo event_info = {
+sizeof (GstEventClass),
+NULL,
+NULL,
+gst_event_class_init,
+NULL,
+NULL,
+sizeof (GstEvent),
+0,
+gst_event_init,
+NULL
+};
+_gst_event_type = g_type_register_static (GST_TYPE_MINI_OBJECT,
+"GstEvent", &event_info, 0);
+for (i = 0; event_quarks[i].name; i++) {
+event_quarks[i].quark = g_quark_from_static_string (event_quarks[i].name);
+}
+}
+return _gst_event_type;
+}
+static void
+gst_event_class_init (gpointer g_class, gpointer class_data)
+{
+GstEventClass *event_class = GST_EVENT_CLASS (g_class);
+parent_class = g_type_class_peek_parent (g_class);
+event_class->mini_object_class.copy =
+(GstMiniObjectCopyFunction) _gst_event_copy;
+event_class->mini_object_class.finalize =
+(GstMiniObjectFinalizeFunction) gst_event_finalize;
+}
+static void
+gst_event_init (GTypeInstance * instance, gpointer g_class)
+{
+GstEvent *event;
+event = GST_EVENT (instance);
+GST_EVENT_TIMESTAMP (event) = GST_CLOCK_TIME_NONE;
+}
+static void
+gst_event_finalize (GstEvent * event)
+{
+g_return_if_fail (event != NULL);
+g_return_if_fail (GST_IS_EVENT (event));
+GST_CAT_LOG (GST_CAT_EVENT, "freeing event %p type %s", event,
+GST_EVENT_TYPE_NAME (event));
+if (GST_EVENT_SRC (event)) {
+gst_object_unref (GST_EVENT_SRC (event));
+GST_EVENT_SRC (event) = NULL;
+}
+if (event->structure) {
+gst_structure_set_parent_refcount (event->structure, NULL);
+gst_structure_free (event->structure);
+}
+GST_MINI_OBJECT_CLASS (parent_class)->finalize (GST_MINI_OBJECT (event));
+}
+static GstEvent *
+_gst_event_copy (GstEvent * event)
+{
+GstEvent *copy;
+copy = (GstEvent *) gst_mini_object_new (GST_TYPE_EVENT);
+GST_EVENT_TYPE (copy) = GST_EVENT_TYPE (event);
+GST_EVENT_TIMESTAMP (copy) = GST_EVENT_TIMESTAMP (event);
+if (GST_EVENT_SRC (event)) {
+GST_EVENT_SRC (copy) = gst_object_ref (GST_EVENT_SRC (event));
+}
+if (event->structure) {
+copy->structure = gst_structure_copy (event->structure);
+gst_structure_set_parent_refcount (copy->structure,
+&copy->mini_object.refcount);
+}
+return copy;
+}
+static GstEvent *
+gst_event_new (GstEventType type)
+{
+GstEvent *event;
+event = (GstEvent *) gst_mini_object_new (GST_TYPE_EVENT);
+GST_CAT_DEBUG (GST_CAT_EVENT, "creating new event %p %s %d", event,
+gst_event_type_get_name (type), type);
+event->type = type;
+event->src = NULL;
+event->structure = NULL;
+return event;
+}
+/**
+* gst_event_new_custom:
+* @type: The type of the new event
+* @structure: The structure for the event. The event will take ownership of
+* the structure.
+*
+* Create a new custom-typed event. This can be used for anything not
+* handled by other event-specific functions to pass an event to another
+* element.
+*
+* Make sure to allocate an event type with the #GST_EVENT_MAKE_TYPE macro,
+* assigning a free number and filling in the correct direction and
+* serialization flags.
+*
+* New custom events can also be created by subclassing the event type if
+* needed.
+*
+* Returns: The new custom event.
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+GstEvent *
+gst_event_new_custom (GstEventType type, GstStructure * structure)
+{
+GstEvent *event;
+/* structure must not have a parent */
+if (structure)
+g_return_val_if_fail (structure->parent_refcount == NULL, NULL);
+event = gst_event_new (type);
+if (structure) {
+gst_structure_set_parent_refcount (structure, &event->mini_object.refcount);
+event->structure = structure;
+}
+return event;
+}
+/**
+* gst_event_get_structure:
+* @event: The #GstEvent.
+*
+* Access the structure of the event.
+*
+* Returns: The structure of the event. The structure is still
+* owned by the event, which means that you should not free it and
+* that the pointer becomes invalid when you free the event.
+*
+* MT safe.
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+const GstStructure *
+gst_event_get_structure (GstEvent * event)
+{
+g_return_val_if_fail (GST_IS_EVENT (event), NULL);
+return event->structure;
+}
+/**
+* gst_event_new_flush_start:
+*
+* Allocate a new flush start event. The flush start event can be sent
+* upstream and downstream and travels out-of-bounds with the dataflow.
+*
+* It marks pads as being flushing and will make them return
+* #GST_FLOW_WRONG_STATE when used for data flow with gst_pad_push(),
+* gst_pad_chain(), gst_pad_alloc_buffer(), gst_pad_get_range() and
+* gst_pad_pull_range(). Any event (except a #GST_EVENT_FLUSH_STOP) received
+* on a flushing pad will return %FALSE immediately.
+*
+* Elements should unlock any blocking functions and exit their streaming
+* functions as fast as possible when this event is received.
+*
+* This event is typically generated after a seek to flush out all queued data
+* in the pipeline so that the new media is played as soon as possible.
+*
+* Returns: A new flush start event.
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+GstEvent *
+gst_event_new_flush_start (void)
+{
+return gst_event_new (GST_EVENT_FLUSH_START);
+}
+/**
+* gst_event_new_flush_stop:
+*
+* Allocate a new flush stop event. The flush stop event can be sent
+* upstream and downstream and travels out-of-bounds with the dataflow.
+* It is typically sent after sending a FLUSH_START event to make the
+* pads accept data again.
+*
+* Elements can process this event synchronized with the dataflow since
+* the preceeding FLUSH_START event stopped the dataflow.
+*
+* This event is typically generated to complete a seek and to resume
+* dataflow.
+*
+* Returns: A new flush stop event.
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+GstEvent *
+gst_event_new_flush_stop (void)
+{
+return gst_event_new (GST_EVENT_FLUSH_STOP);
+}
+/**
+* gst_event_new_eos:
+*
+* Create a new EOS event. The eos event can only travel downstream
+* synchronized with the buffer flow. Elements that receive the EOS
+* event on a pad can return #GST_FLOW_UNEXPECTED as a #GstFlowReturn
+* when data after the EOS event arrives.
+*
+* The EOS event will travel down to the sink elements in the pipeline
+* which will then post the #GST_MESSAGE_EOS on the bus after they have
+* finished playing any buffered data.
+*
+* When all sinks have posted an EOS message, an EOS message is
+* forwarded to the application.
+*
+* Returns: The new EOS event.
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+GstEvent *
+gst_event_new_eos (void)
+{
+return gst_event_new (GST_EVENT_EOS);
+}
+/**
+* gst_event_new_new_segment:
+* @update: is this segment an update to a previous one
+* @rate: a new rate for playback
+* @format: The format of the segment values
+* @start: the start value of the segment
+* @stop: the stop value of the segment
+* @position: stream position
+*
+* Allocate a new newsegment event with the given format/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+values tripplets
+*
+* This method calls gst_event_new_new_segment_full() passing a default
+* value of 1.0 for applied_rate
+*
+* Returns: A new newsegment event.
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+GstEvent *
+gst_event_new_new_segment (gboolean update, gdouble rate, GstFormat format,
+gint64 start, gint64 stop, gint64 position)
+{
+return gst_event_new_new_segment_full (update, rate, 1.0, format, start,
+stop, position);
+}
+/**
+* gst_event_parse_new_segment:
+* @event: The event to query
+* @update: A pointer to the update flag of the segment
+* @rate: A pointer to the rate of the segment
+* @format: A pointer to the format of the newsegment values
+* @start: A pointer to store the start value in
+* @stop: A pointer to store the stop value in
+* @position: A pointer to store the stream time in
+*
+* Get the update flag, rate, format, start, stop and position in the
+* newsegment event. In general, gst_event_parse_new_segment_full() should
+* be used instead of this, to also retrieve the applied_rate value of the
+* segment. See gst_event_new_new_segment_full() for a full description
+* of the newsegment event.
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+void
+gst_event_parse_new_segment (GstEvent * event, gboolean * update,
+gdouble * rate, GstFormat * format, gint64 * start,
+gint64 * stop, gint64 * position)
+{
+gst_event_parse_new_segment_full (event, update, rate, NULL, format, start,
+stop, position);
+}
+/**
+* gst_event_new_new_segment_full:
+* @update: Whether this segment is an update to a previous one
+* @rate: A new rate for playback
+* @applied_rate: The rate factor which has already been applied
+* @format: The format of the segment values
+* @start: The start value of the segment
+* @stop: The stop value of the segment
+* @position: stream position
+*
+* Allocate a new newsegment event with the given format/values triplets.
+*
+* The newsegment event marks the range of buffers to be processed. All
+* data not within the segment range is not to be processed. This can be
+* used intelligently by plugins to apply more efficient methods of skipping
+* unneeded data.
+*
+* The position value of the segment is used in conjunction with the start
+* value to convert the buffer timestamps into the stream time. This is
+* usually done in sinks to report the current stream_time.
+* @position represents the stream_time of a buffer carrying a timestamp of
+* @start. @position cannot be -1.
+*
+* @start cannot be -1, @stop can be -1. If there
+* is a valid @stop given, it must be greater or equal the @start, including
+* when the indicated playback @rate is < 0.
+*
+* The @applied_rate value provides information about any rate adjustment that
+* has already been made to the timestamps and content on the buffers of the
+* stream. (@rate * @applied_rate) should always equal the rate that has been
+* requested for playback. For example, if an element has an input segment
+* with intended playback @rate of 2.0 and applied_rate of 1.0, it can adjust
+* incoming timestamps and buffer content by half and output a newsegment event
+* with @rate of 1.0 and @applied_rate of 2.0
+*
+* After a newsegment event, the buffer stream time is calculated with:
+*
+*   position + (TIMESTAMP(buf) - start) * ABS (rate * applied_rate)
+*
+* Returns: A new newsegment event.
+*
+* Since: 0.10.6
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+GstEvent *
+gst_event_new_new_segment_full (gboolean update, gdouble rate,
+gdouble applied_rate, GstFormat format, gint64 start, gint64 stop,
+gint64 position)
+{
+g_return_val_if_fail (rate != 0.0, NULL);
+g_return_val_if_fail (applied_rate != 0.0, NULL);
+if (format == GST_FORMAT_TIME) {
+GST_CAT_INFO (GST_CAT_EVENT,
+"creating newsegment update %d, rate %lf, format GST_FORMAT_TIME, "
+"start %" GST_TIME_FORMAT ", stop %" GST_TIME_FORMAT
+", position %" GST_TIME_FORMAT,
+update, rate, GST_TIME_ARGS (start),
+GST_TIME_ARGS (stop), GST_TIME_ARGS (position));
+} else {
+GST_CAT_INFO (GST_CAT_EVENT,
+"creating newsegment update %d, rate %lf, format %d, "
+"start %" G_GINT64_FORMAT ", stop %" G_GINT64_FORMAT ", position %"
+G_GINT64_FORMAT, update, rate, format, start, stop, position);
+}
+g_return_val_if_fail (position != -1, NULL);
+g_return_val_if_fail (start != -1, NULL);
+if (stop != -1)
+g_return_val_if_fail (start <= stop, NULL);
+return gst_event_new_custom (GST_EVENT_NEWSEGMENT,
+gst_structure_new ("GstEventNewsegment",
+"update", G_TYPE_BOOLEAN, update,
+"rate", G_TYPE_DOUBLE, rate,
+"applied_rate", G_TYPE_DOUBLE, applied_rate,
+"format", GST_TYPE_FORMAT, format,
+"start", G_TYPE_INT64, start,
+"stop", G_TYPE_INT64, stop,
+"position", G_TYPE_INT64, position, NULL));
+}
+/**
+* gst_event_parse_new_segment_full:
+* @event: The event to query
+* @update: A pointer to the update flag of the segment
+* @rate: A pointer to the rate of the segment
+* @applied_rate: A pointer to the applied_rate of the segment
+* @format: A pointer to the format of the newsegment values
+* @start: A pointer to store the start value in
+* @stop: A pointer to store the stop value in
+* @position: A pointer to store the stream time in
+*
+* Get the update, rate, applied_rate, format, start, stop and
+* position in the newsegment event. See gst_event_new_new_segment_full()
+* for a full description of the newsegment event.
+*
+* Since: 0.10.6
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+void
+gst_event_parse_new_segment_full (GstEvent * event, gboolean * update,
+gdouble * rate, gdouble * applied_rate, GstFormat * format,
+gint64 * start, gint64 * stop, gint64 * position)
+{
+const GstStructure *structure;
+g_return_if_fail (GST_IS_EVENT (event));
+g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_NEWSEGMENT);
+structure = gst_event_get_structure (event);
+if (G_LIKELY (update))
+*update =
+g_value_get_boolean (gst_structure_get_value (structure, "update"));
+if (G_LIKELY (rate))
+*rate = g_value_get_double (gst_structure_get_value (structure, "rate"));
+if (G_LIKELY (applied_rate))
+*applied_rate =
+g_value_get_double (gst_structure_get_value (structure,
+"applied_rate"));
+if (G_LIKELY (format))
+*format = g_value_get_enum (gst_structure_get_value (structure, "format"));
+if (G_LIKELY (start))
+*start = g_value_get_int64 (gst_structure_get_value (structure, "start"));
+if (G_LIKELY (stop))
+*stop = g_value_get_int64 (gst_structure_get_value (structure, "stop"));
+if (G_LIKELY (position))
+*position =
+g_value_get_int64 (gst_structure_get_value (structure, "position"));
+}
+/**
+* gst_event_new_tag:
+* @taglist: metadata list
+*
+* Generates a metadata tag event from the given @taglist.
+*
+* Returns: a new #GstEvent
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+GstEvent *
+gst_event_new_tag (GstTagList * taglist)
+{
+g_return_val_if_fail (taglist != NULL, NULL);
+return gst_event_new_custom (GST_EVENT_TAG, (GstStructure *) taglist);
+}
+/**
+* gst_event_parse_tag:
+* @event: a tag event
+* @taglist: pointer to metadata list
+*
+* Parses a tag @event and stores the results in the given @taglist location.
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+void
+gst_event_parse_tag (GstEvent * event, GstTagList ** taglist)
+{
+g_return_if_fail (GST_IS_EVENT (event));
+g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_TAG);
+if (taglist)
+*taglist = (GstTagList *) event->structure;
+}
+/* buffersize event */
+/**
+* gst_event_new_buffer_size:
+* @format: buffer format
+* @minsize: minimum buffer size
+* @maxsize: maximum buffer size
+* @async: thread behavior
+*
+* Create a new buffersize event. The event is sent downstream and notifies
+* elements that they should provide a buffer of the specified dimensions.
+*
+* When the @async flag is set, a thread boundary is prefered.
+*
+* Returns: a new #GstEvent
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+GstEvent *
+gst_event_new_buffer_size (GstFormat format, gint64 minsize,
+gint64 maxsize, gboolean async)
+{
+GST_CAT_INFO (GST_CAT_EVENT,
+"creating buffersize format %d, minsize %" G_GINT64_FORMAT
+", maxsize %" G_GINT64_FORMAT ", async %d", format,
+minsize, maxsize, async);
+return gst_event_new_custom (GST_EVENT_BUFFERSIZE,
+gst_structure_new ("GstEventBufferSize",
+"format", GST_TYPE_FORMAT, format,
+"minsize", G_TYPE_INT64, minsize,
+"maxsize", G_TYPE_INT64, maxsize,
+"async", G_TYPE_BOOLEAN, async, NULL));
+}
+/**
+* gst_event_parse_buffer_size:
+* @event: The event to query
+* @format: A pointer to store the format in
+* @minsize: A pointer to store the minsize in
+* @maxsize: A pointer to store the maxsize in
+* @async: A pointer to store the async-flag in
+*
+* Get the format, minsize, maxsize and async-flag in the buffersize event.
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+void
+gst_event_parse_buffer_size (GstEvent * event, GstFormat * format,
+gint64 * minsize, gint64 * maxsize, gboolean * async)
+{
+const GstStructure *structure;
+g_return_if_fail (GST_IS_EVENT (event));
+g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_BUFFERSIZE);
+structure = gst_event_get_structure (event);
+if (format)
+*format = g_value_get_enum (gst_structure_get_value (structure, "format"));
+if (minsize)
+*minsize =
+g_value_get_int64 (gst_structure_get_value (structure, "minsize"));
+if (maxsize)
+*maxsize =
+g_value_get_int64 (gst_structure_get_value (structure, "maxsize"));
+if (async)
+*async = g_value_get_boolean (gst_structure_get_value (structure, "async"));
+}
+/**
+* gst_event_new_qos:
+* @proportion: the proportion of the qos message
+* @diff: The time difference of the last Clock sync
+* @timestamp: The timestamp of the buffer
+*
+* Allocate a new qos event with the given values.
+* The QOS event is generated in an element that wants an upstream
+* element to either reduce or increase its rate because of
+* high/low CPU load or other resource usage such as network performance.
+* Typically sinks generate these events for each buffer they receive.
+*
+* @proportion indicates the real-time performance of the streaming in the
+* element that generated the QoS event (usually the sink). The value is
+* generally computed based on more long term statistics about the streams
+* timestamps compared to the clock.
+* A value < 1.0 indicates that the upstream element is producing data faster
+* than real-time. A value > 1.0 indicates that the upstream element is not
+* producing data fast enough. 1.0 is the ideal @proportion value. The
+* proportion value can safely be used to lower or increase the quality of
+* the element.
+*
+* @diff is the difference against the clock in running time of the last
+* buffer that caused the element to generate the QOS event. A negative value
+* means that the buffer with @timestamp arrived in time. A positive value
+* indicates how late the buffer with @timestamp was.
+*
+* @timestamp is the timestamp of the last buffer that cause the element
+* to generate the QOS event. It is expressed in running time and thus an ever
+* increasing value.
+*
+* The upstream element can use the @diff and @timestamp values to decide
+* whether to process more buffers. For possitive @diff, all buffers with
+* timestamp <= @timestamp + @diff will certainly arrive late in the sink
+* as well.
+*
+* The application can use general event probes to intercept the QoS
+* event and implement custom application specific QoS handling.
+*
+* Returns: A new QOS event.
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+GstEvent *
+gst_event_new_qos (gdouble proportion, GstClockTimeDiff diff,
+GstClockTime timestamp)
+{
+GST_CAT_INFO (GST_CAT_EVENT,
+"creating qos proportion %lf, diff %" G_GINT64_FORMAT
+", timestamp %" GST_TIME_FORMAT, proportion,
+diff, GST_TIME_ARGS (timestamp));
+return gst_event_new_custom (GST_EVENT_QOS,
+gst_structure_new ("GstEventQOS",
+"proportion", G_TYPE_DOUBLE, proportion,
+"diff", G_TYPE_INT64, diff,
+"timestamp", G_TYPE_UINT64, timestamp, NULL));
+}
+/**
+* gst_event_parse_qos:
+* @event: The event to query
+* @proportion: A pointer to store the proportion in
+* @diff: A pointer to store the diff in
+* @timestamp: A pointer to store the timestamp in
+*
+* Get the proportion, diff and timestamp in the qos event. See
+* gst_event_new_qos() for more information about the different QoS values.
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+void
+gst_event_parse_qos (GstEvent * event, gdouble * proportion,
+GstClockTimeDiff * diff, GstClockTime * timestamp)
+{
+const GstStructure *structure;
+g_return_if_fail (GST_IS_EVENT (event));
+g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_QOS);
+structure = gst_event_get_structure (event);
+if (proportion)
+*proportion =
+g_value_get_double (gst_structure_get_value (structure, "proportion"));
+if (diff)
+*diff = g_value_get_int64 (gst_structure_get_value (structure, "diff"));
+if (timestamp)
+*timestamp =
+g_value_get_uint64 (gst_structure_get_value (structure, "timestamp"));
+}
+/**
+* gst_event_new_seek:
+* @rate: The new playback rate
+* @format: The format of the seek values
+* @flags: The optional seek flags
+* @start_type: The type and flags for the new start position
+* @start: The value of the new start position
+* @stop_type: The type and flags for the new stop position
+* @stop: The value of the new stop position
+*
+* Allocate a new seek event with the given parameters.
+*
+* The seek event configures playback of the pipeline between @start to @stop
+* at the speed given in @rate, also called a playback segment.
+* The @start and @stop values are expressed in @format.
+*
+* A @rate of 1.0 means normal playback rate, 2.0 means double speed.
+* Negatives values means backwards playback. A value of 0.0 for the
+* rate is not allowed and should be accomplished instead by PAUSING the
+* pipeline.
+*
+* A pipeline has a default playback segment configured with a start
+* position of 0, a stop position of -1 and a rate of 1.0. The currently
+* configured playback segment can be queried with #GST_QUERY_SEGMENT.
+*
+* @start_type and @stop_type specify how to adjust the currently configured
+* start and stop fields in @segment. Adjustments can be made relative or
+* absolute to the last configured values. A type of #GST_SEEK_TYPE_NONE means
+* that the position should not be updated.
+*
+* When the rate is positive and @start has been updated, playback will start
+* from the newly configured start position.
+*
+* For negative rates, playback will start from the newly configured stop
+* position (if any). If the stop position if updated, it must be different from
+* -1 for negative rates.
+*
+* It is not possible to seek relative to the current playback position, to do
+* this, PAUSE the pipeline, query the current playback position with
+* #GST_QUERY_POSITION and update the playback segment current position with a
+* #GST_SEEK_TYPE_SET to the desired position.
+*
+* Returns: A new seek event.
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+GstEvent *
+gst_event_new_seek (gdouble rate, GstFormat format, GstSeekFlags flags,
+GstSeekType start_type, gint64 start, GstSeekType stop_type, gint64 stop)
+{
+g_return_val_if_fail (rate != 0.0, NULL);
+if (format == GST_FORMAT_TIME) {
+GST_CAT_INFO (GST_CAT_EVENT,
+"creating seek rate %lf, format TIME, flags %d, "
+"start_type %d, start %" GST_TIME_FORMAT ", "
+"stop_type %d, stop %" GST_TIME_FORMAT,
+rate, flags, start_type, GST_TIME_ARGS (start),
+stop_type, GST_TIME_ARGS (stop));
+} else {
+GST_CAT_INFO (GST_CAT_EVENT,
+"creating seek rate %lf, format %d, flags %d, "
+"start_type %d, start %" G_GINT64_FORMAT ", "
+"stop_type %d, stop %" G_GINT64_FORMAT,
+rate, format, flags, start_type, start, stop_type, stop);
+}
+return gst_event_new_custom (GST_EVENT_SEEK,
+gst_structure_new ("GstEventSeek", "rate", G_TYPE_DOUBLE, rate,
+"format", GST_TYPE_FORMAT, format,
+"flags", GST_TYPE_SEEK_FLAGS, flags,
+"cur_type", GST_TYPE_SEEK_TYPE, start_type,
+"cur", G_TYPE_INT64, start,
+"stop_type", GST_TYPE_SEEK_TYPE, stop_type,
+"stop", G_TYPE_INT64, stop, NULL));
+}
+/**
+* gst_event_parse_seek:
+* @event: a seek event
+* @rate: result location for the rate
+* @format: result location for the stream format
+* @flags:  result location for the #GstSeekFlags
+* @start_type: result location for the #GstSeekType of the start position
+* @start: result location for the start postion expressed in @format
+* @stop_type:  result location for the #GstSeekType of the stop position
+* @stop: result location for the stop postion expressed in @format
+*
+* Parses a seek @event and stores the results in the given result locations.
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+void
+gst_event_parse_seek (GstEvent * event, gdouble * rate,
+GstFormat * format, GstSeekFlags * flags, GstSeekType * start_type,
+gint64 * start, GstSeekType * stop_type, gint64 * stop)
+{
+const GstStructure *structure;
+g_return_if_fail (GST_IS_EVENT (event));
+g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_SEEK);
+structure = gst_event_get_structure (event);
+if (rate)
+*rate = g_value_get_double (gst_structure_get_value (structure, "rate"));
+if (format)
+*format = g_value_get_enum (gst_structure_get_value (structure, "format"));
+if (flags)
+*flags = g_value_get_flags (gst_structure_get_value (structure, "flags"));
+if (start_type)
+*start_type =
+g_value_get_enum (gst_structure_get_value (structure, "cur_type"));
+if (start)
+*start = g_value_get_int64 (gst_structure_get_value (structure, "cur"));
+if (stop_type)
+*stop_type =
+g_value_get_enum (gst_structure_get_value (structure, "stop_type"));
+if (stop)
+*stop = g_value_get_int64 (gst_structure_get_value (structure, "stop"));
+}
+/**
+* gst_event_new_navigation:
+* @structure: description of the event
+*
+* Create a new navigation event from the given description.
+*
+* Returns: a new #GstEvent
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+GstEvent *
+gst_event_new_navigation (GstStructure * structure)
+{
+g_return_val_if_fail (structure != NULL, NULL);
+return gst_event_new_custom (GST_EVENT_NAVIGATION, structure);
+}
+/**
+* gst_event_new_latency:
+* @latency: the new latency value
+*
+* Create a new latency event. The event is sent upstream from the sinks and
+* notifies elements that they should add an additional @latency to the
+* timestamps before synchronising against the clock.
+*
+* The latency is mostly used in live sinks and is always expressed in
+* the time format.
+*
+* Returns: a new #GstEvent
+*
+* Since: 0.10.12
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+GstEvent *
+gst_event_new_latency (GstClockTime latency)
+{
+GST_CAT_INFO (GST_CAT_EVENT,
+"creating latency event %" GST_TIME_FORMAT, GST_TIME_ARGS (latency));
+return gst_event_new_custom (GST_EVENT_LATENCY,
+gst_structure_new ("GstEventLatency",
+"latency", G_TYPE_UINT64, latency, NULL));
+}
+/**
+* gst_event_parse_latency:
+* @event: The event to query
+* @latency: A pointer to store the latency in.
+*
+* Get the latency in the latency event.
+*
+* Since: 0.10.12
+*/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+void
+gst_event_parse_latency (GstEvent * event, GstClockTime * latency)
+{
+const GstStructure *structure;
+g_return_if_fail (GST_IS_EVENT (event));
+g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_LATENCY);
+structure = gst_event_get_structure (event);
+if (latency)
+*latency =
+g_value_get_uint64 (gst_structure_get_value (structure, "latency"));
+}

changeset 0	0e761a78d257
child 7	567bb019e3e3