| /* 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; |
| |
| 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. |
| */ |
| 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 |
| */ |
| 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. |
| */ |
| GstEventTypeFlags |
| gst_event_type_get_flags (GstEventType type) |
| { |
| GstEventTypeFlags ret; |
| |
| ret = type & ((1 << GST_EVENT_TYPE_SHIFT) - 1); |
| |
| return ret; |
| } |
| |
| 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, |
| ©->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. |
| */ |
| 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. |
| */ |
| 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. |
| */ |
| 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. |
| */ |
| 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. |
| */ |
| 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/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. |
| */ |
| 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. |
| */ |
| 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 |
| */ |
| 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 |
| */ |
| 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 |
| */ |
| 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. |
| */ |
| 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 |
| */ |
| 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. |
| */ |
| 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. |
| */ |
| 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. |
| */ |
| 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. |
| */ |
| 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. |
| */ |
| 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 |
| */ |
| 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 |
| */ |
| 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 |
| */ |
| 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")); |
| } |