/* 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 /** * GstEventTypeFlags: * @GST_EVENT_TYPE_UPSTREAM: Set if the event can travel upstream. * @GST_EVENT_TYPE_DOWNSTREAM: Set if the event can travel downstream. * @GST_EVENT_TYPE_SERIALIZED: Set if the event should be serialized with data * flow. * * #GstEventTypeFlags indicate the aspects of the different #GstEventType * values. You can get the type flags of a #GstEventType with the * gst_event_type_get_flags() function. */ typedef enum { GST_EVENT_TYPE_UPSTREAM = 1 << 0, GST_EVENT_TYPE_DOWNSTREAM = 1 << 1, GST_EVENT_TYPE_SERIALIZED = 1 << 2 } GstEventTypeFlags; /** * GST_EVENT_TYPE_BOTH: * * The same thing as #GST_EVENT_TYPE_UPSTREAM | #GST_EVENT_TYPE_DOWNSTREAM. */ #define GST_EVENT_TYPE_BOTH \ (GST_EVENT_TYPE_UPSTREAM | GST_EVENT_TYPE_DOWNSTREAM) #define GST_EVENT_TYPE_SHIFT 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_EVENT_TYPE_SHIFT) | (flags)) #define FLAG(name) GST_EVENT_TYPE_##name /** * 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_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_LATENCY: Notification of new latency adjustment. Since: 0.10.12 * @GST_EVENT_STEP: A request for stepping through the media. Since: 0.10.24 * @GST_EVENT_CUSTOM_UPSTREAM: Upstream custom event * @GST_EVENT_CUSTOM_DOWNSTREAM: Downstream custom event that travels in the * data flow. * @GST_EVENT_CUSTOM_DOWNSTREAM_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, FLAG(BOTH)), GST_EVENT_FLUSH_STOP = GST_EVENT_MAKE_TYPE (2, FLAG(BOTH) | FLAG(SERIALIZED)), /* downstream serialized events */ GST_EVENT_EOS = GST_EVENT_MAKE_TYPE (5, FLAG(DOWNSTREAM) | FLAG(SERIALIZED)), GST_EVENT_NEWSEGMENT = GST_EVENT_MAKE_TYPE (6, FLAG(DOWNSTREAM) | FLAG(SERIALIZED)), GST_EVENT_TAG = GST_EVENT_MAKE_TYPE (7, FLAG(DOWNSTREAM) | FLAG(SERIALIZED)), GST_EVENT_BUFFERSIZE = GST_EVENT_MAKE_TYPE (8, FLAG(DOWNSTREAM) | FLAG(SERIALIZED)), /* upstream events */ GST_EVENT_QOS = GST_EVENT_MAKE_TYPE (15, FLAG(UPSTREAM)), GST_EVENT_SEEK = GST_EVENT_MAKE_TYPE (16, FLAG(UPSTREAM)), GST_EVENT_NAVIGATION = GST_EVENT_MAKE_TYPE (17, FLAG(UPSTREAM)), GST_EVENT_LATENCY = GST_EVENT_MAKE_TYPE (18, FLAG(UPSTREAM)), GST_EVENT_STEP = GST_EVENT_MAKE_TYPE (19, FLAG(UPSTREAM)), /* custom events start here */ GST_EVENT_CUSTOM_UPSTREAM = GST_EVENT_MAKE_TYPE (32, FLAG(UPSTREAM)), GST_EVENT_CUSTOM_DOWNSTREAM = GST_EVENT_MAKE_TYPE (32, FLAG(DOWNSTREAM) | FLAG(SERIALIZED)), GST_EVENT_CUSTOM_DOWNSTREAM_OOB = GST_EVENT_MAKE_TYPE (32, FLAG(DOWNSTREAM)), GST_EVENT_CUSTOM_BOTH = GST_EVENT_MAKE_TYPE (32, FLAG(BOTH) | FLAG(SERIALIZED)), GST_EVENT_CUSTOM_BOTH_OOB = GST_EVENT_MAKE_TYPE (32, FLAG(BOTH)) } GstEventType; #undef FLAG /** * 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_EVENT_TYPE_UPSTREAM) /** * 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_EVENT_TYPE_DOWNSTREAM) /** * 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_EVENT_TYPE_SERIALIZED) /** * gst_event_replace: * @old_event: pointer to a pointer to a #GstEvent to be replaced. * @new_event: pointer to a #GstEvent that will replace the event pointed to * by @old_event. * * Modifies a pointer to a #GstEvent to point to a different #GstEvent. The * modification is done atomically (so this is useful for ensuring thread safety * in some cases), and the reference counts are updated appropriately (the old * event is unreffed, the new one is reffed). * * Either @new_event or the #GstEvent pointed to by @old_event may be NULL. * * Since: 0.10.3 */ #define gst_event_replace(old_event,new_event) \ gst_mini_object_replace ((GstMiniObject **)(old_event), GST_MINI_OBJECT (new_event)) /** * GstSeekType: * @GST_SEEK_TYPE_NONE: no change in position is required * @GST_SEEK_TYPE_CUR: change relative to currently configured segment. This * can't be used to seek relative to the current playback position - do a * position query, calculate the desired position and then do an absolute * position seek instead if that's what you want to do. * @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 with * gst_event_new_seek(), 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. * @GST_SEEK_FLAG_SKIP: when doing fast foward or fast reverse playback, allow * elements to skip frames instead of generating all * frames. Since 0.10.22. * * Flags to be used with gst_element_seek() or gst_event_new_seek(). All flags * can be used together. * * 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 performing a segment seek: after the playback of the segment completes, * no EOS will be emmited by the element that performed the seek, but a * #GST_MESSAGE_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. * * When doing fast forward (rate > 1.0) or fast reverse (rate < -1.0) trickmode * playback, the @GST_SEEK_FLAG_SKIP flag can be used to instruct decoders * and demuxers to adjust the playback rate by skipping frames. This can improve * performance and decrease CPU usage because not all frames need to be decoded. */ 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), GST_SEEK_FLAG_SKIP = (1 << 4) } 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 >*/ union { guint32 seqnum; gpointer _gst_reserved; } abidata; }; struct _GstEventClass { GstMiniObjectClass mini_object_class; /*< private >*/ gpointer _gst_reserved[GST_PADDING]; }; const gchar* gst_event_type_get_name (GstEventType type); GQuark gst_event_type_to_quark (GstEventType type); GstEventTypeFlags gst_event_type_get_flags (GstEventType type); GType gst_event_get_type (void); /* refcounting */ /** * gst_event_ref: * @event: The event to refcount * * Increase the refcount of this event. * * Returns: @event (for convenience when doing assignments) */ #ifdef _FOOL_GTK_DOC_ G_INLINE_FUNC GstEvent * gst_event_ref (GstEvent * event); #endif static inline GstEvent * gst_event_ref (GstEvent * event) { return (GstEvent *) gst_mini_object_ref (GST_MINI_OBJECT (event)); } /** * gst_event_unref: * @event: The event to refcount * * Decrease the refcount of an event, freeing it if the refcount reaches 0. */ #ifdef _FOOL_GTK_DOC_ G_INLINE_FUNC void gst_event_unref (GstEvent * event); #endif static inline void gst_event_unref (GstEvent * event) { gst_mini_object_unref (GST_MINI_OBJECT (event)); } /* copy event */ /** * gst_event_copy: * @event: The event to copy * * Copy the event using the event specific copy function. */ #ifdef _FOOL_GTK_DOC_ G_INLINE_FUNC void gst_event_copy (GstEvent * event); #endif static inline GstEvent * gst_event_copy (const GstEvent * event) { return GST_EVENT_CAST (gst_mini_object_copy (GST_MINI_OBJECT (event))); } /* custom event */ GstEvent* gst_event_new_custom (GstEventType type, GstStructure *structure); const GstStructure * gst_event_get_structure (GstEvent *event); gboolean gst_event_has_name (GstEvent *event, const gchar *name); /* identifiers for events and messages */ guint32 gst_event_get_seqnum (GstEvent *event); void gst_event_set_seqnum (GstEvent *event, guint32 seqnum); /* 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_new_segment (gboolean update, gdouble rate, GstFormat format, gint64 start, gint64 stop, gint64 position); GstEvent* gst_event_new_new_segment_full (gboolean update, gdouble rate, gdouble applied_rate, GstFormat format, gint64 start, gint64 stop, gint64 position); void gst_event_parse_new_segment (GstEvent *event, gboolean *update, gdouble *rate, GstFormat *format, gint64 *start, gint64 *stop, gint64 *position); void gst_event_parse_new_segment_full (GstEvent *event, gboolean *update, gdouble *rate, gdouble *applied_rate, GstFormat *format, gint64 *start, gint64 *stop, gint64 *position); /* tag event */ GstEvent* gst_event_new_tag (GstTagList *taglist); void gst_event_parse_tag (GstEvent *event, GstTagList **taglist); /* buffer */ GstEvent * gst_event_new_buffer_size (GstFormat format, gint64 minsize, gint64 maxsize, gboolean async); void gst_event_parse_buffer_size (GstEvent *event, GstFormat *format, gint64 *minsize, gint64 *maxsize, gboolean *async); /* QOS events */ 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 start_type, gint64 start, GstSeekType stop_type, gint64 stop); void gst_event_parse_seek (GstEvent *event, gdouble *rate, GstFormat *format, GstSeekFlags *flags, GstSeekType *start_type, gint64 *start, GstSeekType *stop_type, gint64 *stop); /* navigation event */ GstEvent* gst_event_new_navigation (GstStructure *structure); /* latency event */ GstEvent* gst_event_new_latency (GstClockTime latency); void gst_event_parse_latency (GstEvent *event, GstClockTime *latency); /* step event */ GstEvent* gst_event_new_step (GstFormat format, guint64 amount, gdouble rate, gboolean flush, gboolean intermediate); void gst_event_parse_step (GstEvent *event, GstFormat *format, guint64 *amount, gdouble *rate, gboolean *flush, gboolean *intermediate); G_END_DECLS #endif /* __GST_EVENT_H__ */