gstreamer/gst/gstevent.h
Wim Taymans 27daf02ce6 gst/: Fix docs.
Original commit message from CVS:
* gst/gstevent.h:
* gst/gsturi.h:
Fix docs.
2005-11-09 16:16:41 +00:00

380 lines
13 KiB
C

/* 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.h: Header for 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.
*/
#ifndef __GST_EVENT_H__
#define __GST_EVENT_H__
#include <gst/gstminiobject.h>
#include <gst/gstformat.h>
#include <gst/gstobject.h>
#include <gst/gstclock.h>
#include <gst/gststructure.h>
#include <gst/gsttaglist.h>
G_BEGIN_DECLS
/**
* GST_EVDIR_US:
*
* bitmask defining the event can travel upstream
*/
#define GST_EVDIR_US (1 << 0)
/**
* GST_EVDIR_DS:
*
* bitmask defining the event can travel downstream
*/
#define GST_EVDIR_DS (1 << 1)
/**
* GST_EVDIR_BOTH:
*
* bitmask defining the event can travel both up and downstream
*/
#define GST_EVDIR_BOTH GST_EVDIR_US | GST_EVDIR_DS
/**
* GST_EVSER:
*
* mask defining if the event is serialized with the data stream
*/
#define GST_EVSER (1 << 2)
/**
* GST_EVSHIFT:
*
* shift for the bits in the serialize mask.
*/
#define GST_EVSHIFT 4
/**
* GST_EVENT_MAKE_TYPE:
* @num: the event number to create
* @flags: the event flags
*
* when making custom event types, use this macro with the num and
* the given flags
*/
#define GST_EVENT_MAKE_TYPE(num,flags) (((num) << GST_EVSHIFT) | (flags))
/**
* GstEventType:
* @GST_EVENT_UNKNOWN: unknown event.
* @GST_EVENT_FLUSH_START: Start a flush operation
* @GST_EVENT_FLUSH_STOP: Stop a flush operation
* @GST_EVENT_EOS: End-Of-Stream. No more data is to be expected to follow
* without a NEWSEGMENT event.
* @GST_EVENT_NEWSEGMENT: A new media segment follows in the dataflow.
* @GST_EVENT_TAG: A new set of metadata tags has been found in the stream.
* @GST_EVENT_FILLER: Filler for sparse data streams.
* @GST_EVENT_BUFFERSIZE: Notification of buffering requirements
* @GST_EVENT_QOS: A quality message. Used to indicate to upstream elements
* that the downstream elements are being starved of or
* flooded with data.
* @GST_EVENT_SEEK: A request for a new playback position and rate.
* @GST_EVENT_NAVIGATION: Navigation events are usually used for communicating
user requests, such as mouse or keyboard movements,
* to upstream elements.
* @GST_EVENT_CUSTOM_UP: Upstream custom event
* @GST_EVENT_CUSTOM_DS: Downstream custom event that travels in the data flow.
* @GST_EVENT_CUSTOM_DS_OOB: Custom out-of-band downstream event.
* @GST_EVENT_CUSTOM_BOTH: Custom upstream or downstream event.
* In-band when travelling downstream.
* @GST_EVENT_CUSTOM_BOTH_OOB: Custom upstream or downstream out-of-band event.
*
* #GstEventType lists the standard event types that can be sent in a pipeline.
*
* The custom event types can be used for private messages between elements
* that can't be expressed using normal
* GStreamer buffer passing semantics. Custom events carry an arbitrary
* #GstStructure.
* Specific custom events are distinguished by the name of the structure.
*/
/* NOTE: keep in sync with quark registration in gstevent.c */
typedef enum {
GST_EVENT_UNKNOWN = GST_EVENT_MAKE_TYPE (0, 0),
/* bidirectional events */
GST_EVENT_FLUSH_START = GST_EVENT_MAKE_TYPE (1, GST_EVDIR_BOTH),
GST_EVENT_FLUSH_STOP = GST_EVENT_MAKE_TYPE (2, GST_EVDIR_BOTH),
/* downstream serialized events */
GST_EVENT_EOS = GST_EVENT_MAKE_TYPE (5, GST_EVDIR_DS | GST_EVSER),
GST_EVENT_NEWSEGMENT = GST_EVENT_MAKE_TYPE (6, GST_EVDIR_DS | GST_EVSER),
GST_EVENT_TAG = GST_EVENT_MAKE_TYPE (7, GST_EVDIR_DS | GST_EVSER),
GST_EVENT_FILLER = GST_EVENT_MAKE_TYPE (8, GST_EVDIR_DS | GST_EVSER),
GST_EVENT_BUFFERSIZE = GST_EVENT_MAKE_TYPE (9, GST_EVDIR_DS | GST_EVSER),
/* upstream events */
GST_EVENT_QOS = GST_EVENT_MAKE_TYPE (15, GST_EVDIR_US),
GST_EVENT_SEEK = GST_EVENT_MAKE_TYPE (16, GST_EVDIR_US),
GST_EVENT_NAVIGATION = GST_EVENT_MAKE_TYPE (17, GST_EVDIR_US),
/* custom events start here */
GST_EVENT_CUSTOM_UP = GST_EVENT_MAKE_TYPE (32, GST_EVDIR_US),
GST_EVENT_CUSTOM_DS = GST_EVENT_MAKE_TYPE (32, GST_EVDIR_DS | GST_EVSER),
GST_EVENT_CUSTOM_DS_OOB = GST_EVENT_MAKE_TYPE (32, GST_EVDIR_DS),
GST_EVENT_CUSTOM_BOTH = GST_EVENT_MAKE_TYPE (32, GST_EVDIR_BOTH | GST_EVSER),
GST_EVENT_CUSTOM_BOTH_OOB = GST_EVENT_MAKE_TYPE (32, GST_EVDIR_BOTH)
} GstEventType;
/**
* GST_EVENT_TRACE_NAME:
*
* The name used for memory allocation tracing
*/
#define GST_EVENT_TRACE_NAME "GstEvent"
typedef struct _GstEvent GstEvent;
typedef struct _GstEventClass GstEventClass;
#define GST_TYPE_EVENT (gst_event_get_type())
#define GST_IS_EVENT(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_EVENT))
#define GST_IS_EVENT_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_EVENT))
#define GST_EVENT_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_EVENT, GstEventClass))
#define GST_EVENT(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_EVENT, GstEvent))
#define GST_EVENT_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_EVENT, GstEventClass))
#define GST_EVENT_CAST(obj) ((GstEvent *)(obj))
/**
* GST_EVENT_TYPE:
* @event: the event to query
*
* Get the #GstEventType of the event.
*/
#define GST_EVENT_TYPE(event) (GST_EVENT_CAST(event)->type)
/**
* GST_EVENT_TYPE_NAME:
* @event: the event to query
*
* Get a constant string representation of the #GstEventType of the event.
*/
#define GST_EVENT_TYPE_NAME(event) (gst_event_type_get_name(GST_EVENT_TYPE(event)))
/**
* GST_EVENT_TIMESTAMP:
* @event: the event to query
*
* Get the #GstClockTime timestamp of the event. This is the time when the event
* was created.
*/
#define GST_EVENT_TIMESTAMP(event) (GST_EVENT_CAST(event)->timestamp)
/**
* GST_EVENT_SRC:
* @event: the event to query
*
* The source #GstObject that generated this event.
*/
#define GST_EVENT_SRC(event) (GST_EVENT_CAST(event)->src)
/**
* GST_EVENT_IS_UPSTREAM:
* @ev: the event to query
*
* Check if an event can travel upstream.
*/
#define GST_EVENT_IS_UPSTREAM(ev) !!(GST_EVENT_TYPE (ev) & GST_EVDIR_US)
/**
* GST_EVENT_IS_DOWNSTREAM:
* @ev: the event to query
*
* Check if an event can travel downstream.
*/
#define GST_EVENT_IS_DOWNSTREAM(ev) !!(GST_EVENT_TYPE (ev) & GST_EVDIR_DS)
/**
* GST_EVENT_IS_SERIALIZED:
* @ev: the event to query
*
* Check if an event is serialized with the data stream.
*/
#define GST_EVENT_IS_SERIALIZED(ev) !!(GST_EVENT_TYPE (ev) & GST_EVSER)
/**
* GstSeekType:
* @GST_SEEK_TYPE_NONE: no change in position is required
* @GST_SEEK_TYPE_CUR: change relative to current position
* @GST_SEEK_TYPE_SET: absolute position is requested
* @GST_SEEK_TYPE_END: relative position to duration is requested
*
* The different types of seek events. When constructing a seek event, a format,
* a seek method and optional flags are to be provided. The seek event is then
* inserted into the graph with gst_pad_send_event() or
* gst_element_send_event().
*/
typedef enum {
/* one of these */
GST_SEEK_TYPE_NONE = 0,
GST_SEEK_TYPE_CUR = 1,
GST_SEEK_TYPE_SET = 2,
GST_SEEK_TYPE_END = 3
} GstSeekType;
/**
* GstSeekFlags:
* @GST_SEEK_FLAG_NONE: no flag
* @GST_SEEK_FLAG_FLUSH: flush pipeline
* @GST_SEEK_FLAG_ACCURATE: accurate position is requested, this might
* be considerably slower for some formats.
* @GST_SEEK_FLAG_KEY_UNIT: seek to the nearest keyframe. This might be
* faster but less accurate.
* @GST_SEEK_FLAG_SEGMENT: perform a segment seek.
*
* Flags to be used with gst_element_seek() or gst_event_new_seek()
*
* A non flushing seek might take some time to perform as the currently
* playing data in the pipeline will not be cleared.
*
* An accurate seek might be slower for formats that don't have any indexes
* or timestamp markers in the stream. Specifying this flag might require a
* complete scan of the file in those cases.
*
* When perfoming a segment seek: after the playback of the segment completes,
* no EOS will be emmited by the element that performed the seek, but a SEGMENT_DONE
* message will be posted on the bus by the element. When this message is posted, it is
* possible to send a new seek event to continue playback. With this seek method it
* is possible to perform seemless looping or simple linear editing.
*/
typedef enum {
GST_SEEK_FLAG_NONE = 0,
GST_SEEK_FLAG_FLUSH = (1 << 0),
GST_SEEK_FLAG_ACCURATE = (1 << 1),
GST_SEEK_FLAG_KEY_UNIT = (1 << 2),
GST_SEEK_FLAG_SEGMENT = (1 << 3)
} GstSeekFlags;
/**
* GstEvent:
* @mini_object: the parent structure
* @type: the #GstEventType of the event
* @timestamp: the timestamp of the event
* @src: the src of the event
* @structure: the #GstStructure containing the event info.
*
* A #GstEvent.
*/
struct _GstEvent {
GstMiniObject mini_object;
/*< public >*/ /* with COW */
GstEventType type;
guint64 timestamp;
GstObject *src;
GstStructure *structure;
/*< private >*/
gpointer _gst_reserved[GST_PADDING];
};
struct _GstEventClass {
GstMiniObjectClass mini_object_class;
/*< private >*/
gpointer _gst_reserved[GST_PADDING];
};
void _gst_event_initialize (void);
const gchar* gst_event_type_get_name (GstEventType type);
GQuark gst_event_type_to_quark (GstEventType type);
GType gst_event_get_type (void);
/* refcounting */
/**
* gst_event_ref:
* @ev: The event to refcount
*
* Increase the refcount of this event.
*/
#define gst_event_ref(ev) GST_EVENT (gst_mini_object_ref (GST_MINI_OBJECT (ev)))
/**
* gst_event_unref:
* @ev: The event to refcount
*
* Decrease the refcount of an event, freeing it if the refcount reaches 0.
*/
#define gst_event_unref(ev) gst_mini_object_unref (GST_MINI_OBJECT (ev))
/* copy event */
/**
* gst_event_copy:
* @ev: The event to copy
*
* Copy the event using the event specific copy function.
*/
#define gst_event_copy(ev) GST_EVENT_CAST (gst_mini_object_copy (GST_MINI_OBJECT (ev)))
/* custom event */
GstEvent* gst_event_new_custom (GstEventType type, GstStructure *structure);
const GstStructure *
gst_event_get_structure (GstEvent *event);
/* flush events */
GstEvent * gst_event_new_flush_start (void);
GstEvent * gst_event_new_flush_stop (void);
/* EOS event */
GstEvent * gst_event_new_eos (void);
/* newsegment events */
GstEvent* gst_event_new_newsegment (gboolean update, gdouble rate, GstFormat format,
gint64 start_value, gint64 stop_value,
gint64 stream_time);
void gst_event_parse_newsegment (GstEvent *event, gboolean *update, gdouble *rate,
GstFormat *format, gint64 *start_value, gint64 *stop_value,
gint64 *stream_time);
/* tag event */
GstEvent* gst_event_new_tag (GstTagList *taglist);
void gst_event_parse_tag (GstEvent *event, GstTagList **taglist);
/* filler event */
/* FIXME: FILLER events need to be fully specified and implemented */
GstEvent * gst_event_new_filler (void);
/* buffer */
GstEvent * gst_event_new_buffersize (GstFormat format, gint64 minsize, gint64 maxsize,
gboolean async);
void gst_event_parse_buffersize (GstEvent *event, GstFormat *format, gint64 *minsize,
gint64 *maxsize, gboolean *async);
/* QOS events */
/* FIXME: QOS events need to be fully specified and implemented */
GstEvent* gst_event_new_qos (gdouble proportion, GstClockTimeDiff diff,
GstClockTime timestamp);
void gst_event_parse_qos (GstEvent *event, gdouble *proportion, GstClockTimeDiff *diff,
GstClockTime *timestamp);
/* seek event */
GstEvent* gst_event_new_seek (gdouble rate, GstFormat format, GstSeekFlags flags,
GstSeekType cur_type, gint64 cur,
GstSeekType stop_type, gint64 stop);
void gst_event_parse_seek (GstEvent *event, gdouble *rate, GstFormat *format,
GstSeekFlags *flags,
GstSeekType *cur_type, gint64 *cur,
GstSeekType *stop_type, gint64 *stop);
/* navigation event */
GstEvent* gst_event_new_navigation (GstStructure *structure);
G_END_DECLS
#endif /* __GST_EVENT_H__ */