X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=gst%2Fgstevent.c;h=f4bb816863e76472dc42ee663df5ced874b1e40d;hb=dac5966da6a0f53d0443dfa1ac239289028c415d;hp=2b88751d53179e19b2f9233b9e54fa41025c8a03;hpb=5cf8e689440493c51cfc94e178af94f25b04e526;p=platform%2Fupstream%2Fgstreamer.git

diff --git a/gst/gstevent.c b/gst/gstevent.c
index 2b88751..f4bb816 100644
--- a/gst/gstevent.c
+++ b/gst/gstevent.c
@@ -17,12 +17,13 @@
  *
  * 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.
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
  */
 
 /**
  * SECTION:gstevent
+ * @title: GstEvent
  * @short_description: Structure describing events that are passed up and down
  *                     a pipeline
  * @see_also: #GstPad, #GstElement
@@ -36,31 +37,29 @@
  * 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 
+ * 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. 
- * 
+ * 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. 
+ * 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>
+ * the needed parameters to specify seeking time and mode.
+ * |[<!-- language="C" -->
  *   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, 
+ *   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);
@@ -69,10 +68,7 @@
  *   if (!result)
  *     g_warning ("seek failed");
  *   ...
- *   </programlisting>
- * </example>
- *
- * Last reviewed on 2006-09-6 (0.10.10)
+ * ]|
  */
 
 
@@ -84,6 +80,7 @@
 #include "gstenumtypes.h"
 #include "gstutils.h"
 #include "gstquark.h"
+#include "gstvalue.h"
 
 GType _gst_event_type = 0;
 
@@ -92,6 +89,7 @@ typedef struct
   GstEvent event;
 
   GstStructure *structure;
+  gint64 running_time_offset;
 } GstEventImpl;
 
 #define GST_EVENT_STRUCTURE(e)  (((GstEventImpl *)(e))->structure)
@@ -107,33 +105,45 @@ 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_SELECT_STREAMS, "select-streams", 0},
+  {GST_EVENT_STREAM_START, "stream-start", 0},
+  {GST_EVENT_STREAM_COLLECTION, "stream-collection", 0},
   {GST_EVENT_CAPS, "caps", 0},
   {GST_EVENT_SEGMENT, "segment", 0},
   {GST_EVENT_TAG, "tag", 0},
+  {GST_EVENT_TOC, "toc", 0},
+  {GST_EVENT_PROTECTION, "protection", 0},
   {GST_EVENT_BUFFERSIZE, "buffersize", 0},
   {GST_EVENT_SINK_MESSAGE, "sink-message", 0},
+  {GST_EVENT_EOS, "eos", 0},
+  {GST_EVENT_SEGMENT_DONE, "segment-done", 0},
+  {GST_EVENT_GAP, "gap", 0},
   {GST_EVENT_QOS, "qos", 0},
   {GST_EVENT_SEEK, "seek", 0},
   {GST_EVENT_NAVIGATION, "navigation", 0},
   {GST_EVENT_LATENCY, "latency", 0},
   {GST_EVENT_STEP, "step", 0},
   {GST_EVENT_RECONFIGURE, "reconfigure", 0},
+  {GST_EVENT_TOC_SELECT, "toc-select", 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_DOWNSTREAM_STICKY, "custom-downstream-sticky", 0},
   {GST_EVENT_CUSTOM_BOTH, "custom-both", 0},
   {GST_EVENT_CUSTOM_BOTH_OOB, "custom-both-oob", 0},
+  {GST_EVENT_STREAM_GROUP_DONE, "stream-group-done", 0},
 
   {0, NULL, 0}
 };
 
+GST_DEFINE_MINI_OBJECT_TYPE (GstEvent, gst_event);
+
 void
-_gst_event_initialize (void)
+_priv_gst_event_initialize (void)
 {
   gint i;
 
-  _gst_event_type = gst_mini_object_register ("GstEvent");
+  _gst_event_type = gst_event_get_type ();
 
   g_type_class_ref (gst_seek_flags_get_type ());
   g_type_class_ref (gst_seek_type_get_type ());
@@ -196,7 +206,7 @@ gst_event_type_get_flags (GstEventType type)
 {
   GstEventTypeFlags ret;
 
-  ret = type & ((1 << GST_EVENT_STICKY_SHIFT) - 1);
+  ret = type & ((1 << GST_EVENT_NUM_SHIFT) - 1);
 
   return ret;
 }
@@ -218,12 +228,14 @@ _gst_event_free (GstEvent * event)
     gst_structure_set_parent_refcount (s, NULL);
     gst_structure_free (s);
   }
+#ifdef USE_POISONING
+  memset (event, 0xff, sizeof (GstEventImpl));
+#endif
 
-  g_slice_free1 (GST_MINI_OBJECT_SIZE (event), event);
+  g_slice_free1 (sizeof (GstEventImpl), event);
 }
 
-static void gst_event_init (GstEventImpl * event, gsize size,
-    GstEventType type);
+static void gst_event_init (GstEventImpl * event, GstEventType type);
 
 static GstEvent *
 _gst_event_copy (GstEvent * event)
@@ -233,7 +245,7 @@ _gst_event_copy (GstEvent * event)
 
   copy = g_slice_new0 (GstEventImpl);
 
-  gst_event_init (copy, sizeof (GstEventImpl), GST_EVENT_TYPE (event));
+  gst_event_init (copy, GST_EVENT_TYPE (event));
 
   GST_EVENT_TIMESTAMP (copy) = GST_EVENT_TIMESTAMP (event);
   GST_EVENT_SEQNUM (copy) = GST_EVENT_SEQNUM (event);
@@ -243,37 +255,29 @@ _gst_event_copy (GstEvent * event)
     GST_EVENT_STRUCTURE (copy) = gst_structure_copy (s);
     gst_structure_set_parent_refcount (GST_EVENT_STRUCTURE (copy),
         &copy->event.mini_object.refcount);
+  } else {
+    GST_EVENT_STRUCTURE (copy) = NULL;
   }
+
+  ((GstEventImpl *) copy)->running_time_offset =
+      ((GstEventImpl *) event)->running_time_offset;
+
   return GST_EVENT_CAST (copy);
 }
 
 static void
-gst_event_init (GstEventImpl * event, gsize size, GstEventType type)
+gst_event_init (GstEventImpl * event, GstEventType type)
 {
-  gst_mini_object_init (GST_MINI_OBJECT_CAST (event), _gst_event_type, size);
-
-  event->event.mini_object.copy = (GstMiniObjectCopyFunction) _gst_event_copy;
-  event->event.mini_object.free = (GstMiniObjectFreeFunction) _gst_event_free;
+  gst_mini_object_init (GST_MINI_OBJECT_CAST (event), 0, _gst_event_type,
+      (GstMiniObjectCopyFunction) _gst_event_copy, NULL,
+      (GstMiniObjectFreeFunction) _gst_event_free);
 
   GST_EVENT_TYPE (event) = type;
   GST_EVENT_TIMESTAMP (event) = GST_CLOCK_TIME_NONE;
   GST_EVENT_SEQNUM (event) = gst_util_seqnum_next ();
+  event->running_time_offset = 0;
 }
 
-static GstEvent *
-gst_event_new (GstEventType type)
-{
-  GstEventImpl *event;
-
-  event = g_slice_new0 (GstEventImpl);
-
-  GST_CAT_DEBUG (GST_CAT_EVENT, "creating new event %p %s %d", event,
-      gst_event_type_get_name (type), type);
-
-  gst_event_init (event, sizeof (GstEventImpl), type);
-
-  return GST_EVENT_CAST (event);
-}
 
 /**
  * gst_event_new_custom:
@@ -292,28 +296,35 @@ gst_event_new (GstEventType type)
  * New custom events can also be created by subclassing the event type if
  * needed.
  *
- * Returns: (transfer full): the new custom event.
+ * Returns: (transfer full) (nullable): the new custom event.
  */
 GstEvent *
 gst_event_new_custom (GstEventType type, GstStructure * structure)
 {
-  GstEvent *event;
+  GstEventImpl *event;
+
+  event = g_slice_new0 (GstEventImpl);
+
+  GST_CAT_DEBUG (GST_CAT_EVENT, "creating new event %p %s %d", event,
+      gst_event_type_get_name (type), type);
 
-  /* structure must not have a parent */
-  event = gst_event_new (type);
   if (structure) {
+    /* structure must not have a parent */
     if (!gst_structure_set_parent_refcount (structure,
-            &event->mini_object.refcount))
+            &event->event.mini_object.refcount))
       goto had_parent;
 
-    GST_EVENT_STRUCTURE (event) = structure;
   }
-  return event;
+  gst_event_init (event, type);
+
+  GST_EVENT_STRUCTURE (event) = structure;
+
+  return GST_EVENT_CAST (event);
 
   /* ERRORS */
 had_parent:
   {
-    gst_event_unref (event);
+    g_slice_free1 (sizeof (GstEventImpl), event);
     g_warning ("structure is already owned by another object");
     return NULL;
   }
@@ -325,9 +336,9 @@ had_parent:
  *
  * 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.
+ * Returns: (transfer none) (nullable): 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.
  */
@@ -345,10 +356,11 @@ gst_event_get_structure (GstEvent * event)
  *
  * Get a writable version of the structure.
  *
- * 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.
- * This function checks if @event is writable and will never return NULL.
+ * Returns: (transfer none): 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.
+ * This function checks if @event is writable and will never return
+ * %NULL.
  *
  * MT safe.
  */
@@ -364,7 +376,7 @@ gst_event_writable_structure (GstEvent * event)
 
   if (structure == NULL) {
     structure =
-        gst_structure_id_empty_new (gst_event_type_to_quark (GST_EVENT_TYPE
+        gst_structure_new_id_empty (gst_event_type_to_quark (GST_EVENT_TYPE
             (event)));
     gst_structure_set_parent_refcount (structure, &event->mini_object.refcount);
     GST_EVENT_STRUCTURE (event) = structure;
@@ -381,8 +393,6 @@ gst_event_writable_structure (GstEvent * event)
  * check the name of a custom event.
  *
  * Returns: %TRUE if @name matches the name of the event structure.
- *
- * Since: 0.10.20
  */
 gboolean
 gst_event_has_name (GstEvent * event, const gchar * name)
@@ -415,8 +425,6 @@ gst_event_has_name (GstEvent * event, const gchar * name)
  * Returns: The event's sequence number.
  *
  * MT safe.
- *
- * Since: 0.10.22
  */
 guint32
 gst_event_get_seqnum (GstEvent * event)
@@ -438,20 +446,65 @@ gst_event_get_seqnum (GstEvent * event)
  * more information.
  *
  * MT safe.
- *
- * Since: 0.10.22
  */
 void
 gst_event_set_seqnum (GstEvent * event, guint32 seqnum)
 {
   g_return_if_fail (GST_IS_EVENT (event));
+  g_return_if_fail (seqnum != GST_SEQNUM_INVALID);
+  g_return_if_fail (gst_event_is_writable (event));
 
   GST_EVENT_SEQNUM (event) = seqnum;
 }
 
-/* FIXME 0.11: It would be nice to have flush events
- * that don't reset the running time in the sinks
+/**
+ * gst_event_get_running_time_offset:
+ * @event: A #GstEvent.
+ *
+ * Retrieve the accumulated running time offset of the event.
+ *
+ * Events passing through #GstPads that have a running time
+ * offset set via gst_pad_set_offset() will get their offset
+ * adjusted according to the pad's offset.
+ *
+ * If the event contains any information that related to the
+ * running time, this information will need to be updated
+ * before usage with this offset.
+ *
+ * Returns: The event's running time offset
+ *
+ * MT safe.
+ *
+ * Since: 1.4
+ */
+gint64
+gst_event_get_running_time_offset (GstEvent * event)
+{
+  g_return_val_if_fail (GST_IS_EVENT (event), 0);
+
+  return ((GstEventImpl *) event)->running_time_offset;
+}
+
+/**
+ * gst_event_set_running_time_offset:
+ * @event: A #GstEvent.
+ * @offset: A the new running time offset
+ *
+ * Set the running time offset of a event. See
+ * gst_event_get_running_time_offset() for more information.
+ *
+ * MT safe.
+ *
+ * Since: 1.4
  */
+void
+gst_event_set_running_time_offset (GstEvent * event, gint64 offset)
+{
+  g_return_if_fail (GST_IS_EVENT (event));
+  g_return_if_fail (gst_event_is_writable (event));
+
+  ((GstEventImpl *) event)->running_time_offset = offset;
+}
 
 /**
  * gst_event_new_flush_start:
@@ -460,9 +513,9 @@ gst_event_set_seqnum (GstEvent * event, guint32 seqnum)
  * 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
+ * #GST_FLOW_FLUSHING when used for data flow with gst_pad_push(),
+ * gst_pad_chain(), 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
@@ -476,7 +529,7 @@ gst_event_set_seqnum (GstEvent * event, guint32 seqnum)
 GstEvent *
 gst_event_new_flush_start (void)
 {
-  return gst_event_new (GST_EVENT_FLUSH_START);
+  return gst_event_new_custom (GST_EVENT_FLUSH_START, NULL);
 }
 
 /**
@@ -489,7 +542,7 @@ gst_event_new_flush_start (void)
  * pads accept data again.
  *
  * Elements can process this event synchronized with the dataflow since
- * the preceeding FLUSH_START event stopped the dataflow.
+ * the preceding FLUSH_START event stopped the dataflow.
  *
  * This event is typically generated to complete a seek and to resume
  * dataflow.
@@ -504,7 +557,7 @@ gst_event_new_flush_stop (gboolean reset_time)
   GST_CAT_INFO (GST_CAT_EVENT, "creating flush stop %d", reset_time);
 
   event = gst_event_new_custom (GST_EVENT_FLUSH_STOP,
-      gst_structure_id_new (GST_QUARK (EVENT_FLUSH_STOP),
+      gst_structure_new_id (GST_QUARK (EVENT_FLUSH_STOP),
           GST_QUARK (RESET_TIME), G_TYPE_BOOLEAN, reset_time, NULL));
 
   return event;
@@ -533,11 +586,142 @@ gst_event_parse_flush_stop (GstEvent * event, gboolean * reset_time)
 }
 
 /**
+ * gst_event_new_select_streams:
+ * @streams: (element-type utf8) (transfer none): the list of streams to
+ * activate
+ *
+ * Allocate a new select-streams event.
+ *
+ * The select-streams event requests the specified @streams to be activated.
+ *
+ * The list of @streams corresponds to the "Stream ID" of each stream to be
+ * activated. Those ID can be obtained via the #GstStream objects present
+ * in #GST_EVENT_STREAM_START, #GST_EVENT_STREAM_COLLECTION or
+ * #GST_MESSAGE_STREAM_COLLECTION.
+ *
+ * Note: The list of @streams can not be empty.
+ *
+ * Returns: (transfer full): a new select-streams event or %NULL in case of
+ * an error (like an empty streams list).
+ *
+ * Since: 1.10
+ */
+GstEvent *
+gst_event_new_select_streams (GList * streams)
+{
+  GstEvent *event;
+  GValue val = G_VALUE_INIT;
+  GstStructure *struc;
+  GList *tmpl;
+
+  g_return_val_if_fail (streams != NULL, NULL);
+
+  GST_CAT_INFO (GST_CAT_EVENT, "Creating new select-streams event");
+  struc = gst_structure_new_id_empty (GST_QUARK (EVENT_SELECT_STREAMS));
+  g_value_init (&val, GST_TYPE_LIST);
+  /* Fill struc with streams */
+  for (tmpl = streams; tmpl; tmpl = tmpl->next) {
+    GValue strval = G_VALUE_INIT;
+    const gchar *str = (const gchar *) tmpl->data;
+    g_value_init (&strval, G_TYPE_STRING);
+    g_value_set_string (&strval, str);
+    gst_value_list_append_and_take_value (&val, &strval);
+  }
+  gst_structure_id_take_value (struc, GST_QUARK (STREAMS), &val);
+  event = gst_event_new_custom (GST_EVENT_SELECT_STREAMS, struc);
+
+  return event;
+}
+
+/**
+ * gst_event_parse_select_streams:
+ * @event: The event to parse
+ * @streams: (out) (element-type utf8) (transfer full): the streams
+ *
+ * Parse the SELECT_STREAMS event and retrieve the contained streams.
+ *
+ * Since: 1.10
+ */
+void
+gst_event_parse_select_streams (GstEvent * event, GList ** streams)
+{
+  GstStructure *structure;
+  GList *res = NULL;
+
+  g_return_if_fail (GST_IS_EVENT (event));
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_SELECT_STREAMS);
+
+  structure = GST_EVENT_STRUCTURE (event);
+  if (G_LIKELY (streams)) {
+    const GValue *vlist =
+        gst_structure_id_get_value (structure, GST_QUARK (STREAMS));
+    guint i, sz = gst_value_list_get_size (vlist);
+    for (i = 0; i < sz; i++) {
+      const GValue *strv = gst_value_list_get_value (vlist, i);
+      res = g_list_append (res, g_value_dup_string (strv));
+    }
+    *streams = res;
+  }
+}
+
+
+/**
+ * gst_event_new_stream_group_done:
+ * @group_id: the group id of the stream group which is ending
+ *
+ * Create a new Stream Group Done event. The stream-group-done event can
+ * only travel downstream synchronized with the buffer flow. Elements
+ * that receive the event on a pad should handle it mostly like EOS,
+ * and emit any data or pending buffers that would depend on more data
+ * arriving and unblock, since there won't be any more data.
+ *
+ * This event is followed by EOS at some point in the future, and is
+ * generally used when switching pads - to unblock downstream so that
+ * new pads can be exposed before sending EOS on the existing pads.
+ *
+ * Returns: (transfer full): the new stream-group-done event.
+ *
+ * Since: 1.10
+ */
+GstEvent *
+gst_event_new_stream_group_done (guint group_id)
+{
+  GstStructure *s;
+
+  s = gst_structure_new_id (GST_QUARK (EVENT_STREAM_GROUP_DONE),
+      GST_QUARK (GROUP_ID), G_TYPE_UINT, group_id, NULL);
+
+  return gst_event_new_custom (GST_EVENT_STREAM_GROUP_DONE, s);
+}
+
+/**
+ * gst_event_parse_stream_group_done:
+ * @event: a stream-group-done event.
+ * @group_id: (out): address of variable to store the group id into
+ *
+ * Parse a stream-group-done @event and store the result in the given
+ * @group_id location.
+ *
+ * Since: 1.10
+ */
+void
+gst_event_parse_stream_group_done (GstEvent * event, guint * group_id)
+{
+  g_return_if_fail (event != NULL);
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_STREAM_GROUP_DONE);
+
+  if (group_id) {
+    gst_structure_id_get (GST_EVENT_STRUCTURE (event),
+        GST_QUARK (GROUP_ID), G_TYPE_UINT, group_id, NULL);
+  }
+}
+
+/**
  * 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
+ * event on a pad can return #GST_FLOW_EOS as a #GstFlowReturn
  * when data after the EOS event arrives.
  *
  * The EOS event will travel down to the sink elements in the pipeline
@@ -554,18 +738,76 @@ gst_event_parse_flush_stop (GstEvent * event, gboolean * reset_time)
 GstEvent *
 gst_event_new_eos (void)
 {
-  return gst_event_new (GST_EVENT_EOS);
+  return gst_event_new_custom (GST_EVENT_EOS, NULL);
+}
+
+/**
+ * gst_event_new_gap:
+ * @timestamp: the start time (pts) of the gap
+ * @duration: the duration of the gap
+ *
+ * Create a new GAP event. A gap event can be thought of as conceptually
+ * equivalent to a buffer to signal that there is no data for a certain
+ * amount of time. This is useful to signal a gap to downstream elements
+ * which may wait for data, such as muxers or mixers or overlays, especially
+ * for sparse streams such as subtitle streams.
+ *
+ * Returns: (transfer full): the new GAP event.
+ */
+GstEvent *
+gst_event_new_gap (GstClockTime timestamp, GstClockTime duration)
+{
+  GstEvent *event;
+
+  g_return_val_if_fail (GST_CLOCK_TIME_IS_VALID (timestamp), NULL);
+
+  GST_CAT_TRACE (GST_CAT_EVENT, "creating gap %" GST_TIME_FORMAT " - "
+      "%" GST_TIME_FORMAT " (duration: %" GST_TIME_FORMAT ")",
+      GST_TIME_ARGS (timestamp), GST_TIME_ARGS (timestamp + duration),
+      GST_TIME_ARGS (duration));
+
+  event = gst_event_new_custom (GST_EVENT_GAP,
+      gst_structure_new_id (GST_QUARK (EVENT_GAP),
+          GST_QUARK (TIMESTAMP), GST_TYPE_CLOCK_TIME, timestamp,
+          GST_QUARK (DURATION), GST_TYPE_CLOCK_TIME, duration, NULL));
+
+  return event;
+}
+
+/**
+ * gst_event_parse_gap:
+ * @event: a #GstEvent of type #GST_EVENT_GAP
+ * @timestamp: (out) (allow-none): location where to store the
+ *     start time (pts) of the gap, or %NULL
+ * @duration: (out) (allow-none): location where to store the duration of
+ *     the gap, or %NULL
+ *
+ * Extract timestamp and duration from a new GAP event.
+ */
+void
+gst_event_parse_gap (GstEvent * event, GstClockTime * timestamp,
+    GstClockTime * duration)
+{
+  GstStructure *structure;
+
+  g_return_if_fail (GST_IS_EVENT (event));
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_GAP);
+
+  structure = GST_EVENT_STRUCTURE (event);
+  gst_structure_id_get (structure,
+      GST_QUARK (TIMESTAMP), GST_TYPE_CLOCK_TIME, timestamp,
+      GST_QUARK (DURATION), GST_TYPE_CLOCK_TIME, duration, NULL);
 }
 
 /**
  * gst_event_new_caps:
- * @caps: a #GstCaps
+ * @caps: (transfer none): a #GstCaps
  *
  * Create a new CAPS event for @caps. The caps event can only travel downstream
  * synchronized with the buffer flow and contains the format of the buffers
  * that will follow after the event.
  *
- * Returns: (transfer full): the new CAPS event.
+ * Returns: (transfer full) (nullable): the new CAPS event.
  */
 GstEvent *
 gst_event_new_caps (GstCaps * caps)
@@ -578,7 +820,7 @@ gst_event_new_caps (GstCaps * caps)
   GST_CAT_INFO (GST_CAT_EVENT, "creating caps event %" GST_PTR_FORMAT, caps);
 
   event = gst_event_new_custom (GST_EVENT_CAPS,
-      gst_structure_id_new (GST_QUARK (EVENT_CAPS),
+      gst_structure_new_id (GST_QUARK (EVENT_CAPS),
           GST_QUARK (CAPS), GST_TYPE_CAPS, caps, NULL));
 
   return event;
@@ -587,7 +829,7 @@ gst_event_new_caps (GstCaps * caps)
 /**
  * gst_event_parse_caps:
  * @event: The event to parse
- * @caps: (out): A pointer to the caps
+ * @caps: (out) (transfer none): A pointer to the caps
  *
  * Get the caps from @event. The caps remains valid as long as @event remains
  * valid.
@@ -609,13 +851,13 @@ gst_event_parse_caps (GstEvent * event, GstCaps ** caps)
 
 /**
  * gst_event_new_segment:
- * @segment: a #GstSegment
+ * @segment: (transfer none): a #GstSegment
  *
  * Create a new SEGMENT event for @segment. The segment event can only travel
  * downstream synchronized with the buffer flow and contains timing information
  * and playback properties for the buffers that will follow.
  *
- * The newsegment event marks the range of buffers to be processed. All
+ * The segment 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 valid range is expressed with the @start and @stop
@@ -636,27 +878,30 @@ gst_event_parse_caps (GstEvent * event, GstCaps ** caps)
  * 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
+ * incoming timestamps and buffer content by half and output a segment event
  * with @rate of 1.0 and @applied_rate of 2.0
  *
- * After a newsegment event, the buffer stream time is calculated with:
+ * After a segment event, the buffer stream time is calculated with:
  *
  *   time + (TIMESTAMP(buf) - start) * ABS (rate * applied_rate)
  *
- * Returns: (transfer full): the new SEGMENT event.
+ * Returns: (transfer full) (nullable): the new SEGMENT event.
  */
 GstEvent *
-gst_event_new_segment (GstSegment * segment)
+gst_event_new_segment (const GstSegment * segment)
 {
   GstEvent *event;
 
   g_return_val_if_fail (segment != NULL, NULL);
+  g_return_val_if_fail (segment->rate != 0.0, NULL);
+  g_return_val_if_fail (segment->applied_rate != 0.0, NULL);
+  g_return_val_if_fail (segment->format != GST_FORMAT_UNDEFINED, NULL);
 
   GST_CAT_INFO (GST_CAT_EVENT, "creating segment event %" GST_SEGMENT_FORMAT,
       segment);
 
   event = gst_event_new_custom (GST_EVENT_SEGMENT,
-      gst_structure_id_new (GST_QUARK (EVENT_SEGMENT),
+      gst_structure_new_id (GST_QUARK (EVENT_SEGMENT),
           GST_QUARK (SEGMENT), GST_TYPE_SEGMENT, segment, NULL));
 
   return event;
@@ -715,14 +960,28 @@ gst_event_copy_segment (GstEvent * event, GstSegment * segment)
  *
  * Generates a metadata tag event from the given @taglist.
  *
+ * The scope of the taglist specifies if the taglist applies to the
+ * complete medium or only to this specific stream. As the tag event
+ * is a sticky event, elements should merge tags received from
+ * upstream with a given scope with their own tags with the same
+ * scope and create a new tag event from it.
+ *
  * Returns: (transfer full): a new #GstEvent
  */
 GstEvent *
 gst_event_new_tag (GstTagList * taglist)
 {
+  GstStructure *s;
+  GValue val = G_VALUE_INIT;
+  const gchar *names[] = { "GstTagList-stream", "GstTagList-global" };
+
   g_return_val_if_fail (taglist != NULL, NULL);
 
-  return gst_event_new_custom (GST_EVENT_TAG, (GstStructure *) taglist);
+  s = gst_structure_new_empty (names[gst_tag_list_get_scope (taglist)]);
+  g_value_init (&val, GST_TYPE_TAG_LIST);
+  g_value_take_boxed (&val, taglist);
+  gst_structure_id_take_value (s, GST_QUARK (TAGLIST), &val);
+  return gst_event_new_custom (GST_EVENT_TAG, s);
 }
 
 /**
@@ -738,11 +997,16 @@ gst_event_new_tag (GstTagList * taglist)
 void
 gst_event_parse_tag (GstEvent * event, GstTagList ** taglist)
 {
+  const GValue *val;
+
   g_return_if_fail (GST_IS_EVENT (event));
   g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_TAG);
 
+  val = gst_structure_id_get_value (GST_EVENT_STRUCTURE (event),
+      GST_QUARK (TAGLIST));
+
   if (taglist)
-    *taglist = (GstTagList *) GST_EVENT_STRUCTURE (event);
+    *taglist = (GstTagList *) g_value_get_boxed (val);
 }
 
 /* buffersize event */
@@ -756,7 +1020,7 @@ gst_event_parse_tag (GstEvent * event, GstTagList ** taglist)
  * 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.
+ * When the @async flag is set, a thread boundary is preferred.
  *
  * Returns: (transfer full): a new #GstEvent
  */
@@ -772,7 +1036,7 @@ gst_event_new_buffer_size (GstFormat format, gint64 minsize,
       ", maxsize %" G_GINT64_FORMAT ", async %d", gst_format_get_name (format),
       minsize, maxsize, async);
 
-  structure = gst_structure_id_new (GST_QUARK (EVENT_BUFFER_SIZE),
+  structure = gst_structure_new_id (GST_QUARK (EVENT_BUFFER_SIZE),
       GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
       GST_QUARK (MINSIZE), G_TYPE_INT64, minsize,
       GST_QUARK (MAXSIZE), G_TYPE_INT64, maxsize,
@@ -837,7 +1101,7 @@ gst_event_parse_buffer_size (GstEvent * event, GstFormat * format,
  * @type indicates the reason for the QoS event. #GST_QOS_TYPE_OVERFLOW is
  * used when a buffer arrived in time or when the sink cannot keep up with
  * the upstream datarate. #GST_QOS_TYPE_UNDERFLOW is when the sink is not
- * receiving buffers fast enough and thus has to drop late buffers. 
+ * receiving buffers fast enough and thus has to drop late buffers.
  * #GST_QOS_TYPE_THROTTLE is used when the datarate is artificially limited
  * by the application, for example to reduce power consumption.
  *
@@ -862,7 +1126,7 @@ gst_event_parse_buffer_size (GstEvent * event, GstFormat * format,
  * 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
+ * whether to process more buffers. For positive @diff, all buffers with
  * timestamp <= @timestamp + @diff will certainly arrive late in the sink
  * as well. A (negative) @diff value so that @timestamp + @diff would yield a
  * result smaller than 0 is not allowed.
@@ -870,7 +1134,7 @@ gst_event_parse_buffer_size (GstEvent * event, GstFormat * format,
  * The application can use general event probes to intercept the QoS
  * event and implement custom application specific QoS handling.
  *
- * Returns: (transfer full): a new QOS event.
+ * Returns: (transfer full) (nullable): a new QOS event.
  */
 GstEvent *
 gst_event_new_qos (GstQOSType type, gdouble proportion,
@@ -882,12 +1146,12 @@ gst_event_new_qos (GstQOSType type, gdouble proportion,
   /* diff must be positive or timestamp + diff must be positive */
   g_return_val_if_fail (diff >= 0 || -diff <= timestamp, NULL);
 
-  GST_CAT_INFO (GST_CAT_EVENT,
+  GST_CAT_LOG (GST_CAT_EVENT,
       "creating qos type %d, proportion %lf, diff %" G_GINT64_FORMAT
       ", timestamp %" GST_TIME_FORMAT, type, proportion,
       diff, GST_TIME_ARGS (timestamp));
 
-  structure = gst_structure_id_new (GST_QUARK (EVENT_QOS),
+  structure = gst_structure_new_id (GST_QUARK (EVENT_QOS),
       GST_QUARK (TYPE), GST_TYPE_QOS_TYPE, type,
       GST_QUARK (PROPORTION), G_TYPE_DOUBLE, proportion,
       GST_QUARK (DIFF), G_TYPE_INT64, diff,
@@ -907,6 +1171,8 @@ gst_event_new_qos (GstQOSType type, gdouble proportion,
  *
  * Get the type, proportion, diff and timestamp in the qos event. See
  * gst_event_new_qos() for more information about the different QoS values.
+ *
+ * @timestamp will be adjusted for any pad offsets of pads it was passing through.
  */
 void
 gst_event_parse_qos (GstEvent * event, GstQOSType * type,
@@ -930,10 +1196,26 @@ gst_event_parse_qos (GstEvent * event, GstQOSType * type,
     *diff =
         g_value_get_int64 (gst_structure_id_get_value (structure,
             GST_QUARK (DIFF)));
-  if (timestamp)
+  if (timestamp) {
+    gint64 offset = gst_event_get_running_time_offset (event);
+    GstClockTimeDiff diff_ =
+        g_value_get_int64 (gst_structure_id_get_value (structure,
+            GST_QUARK (DIFF)));
+
     *timestamp =
         g_value_get_uint64 (gst_structure_id_get_value (structure,
             GST_QUARK (TIMESTAMP)));
+    /* Catch underflows */
+    if (*timestamp > -offset)
+      *timestamp += offset;
+    else
+      *timestamp = 0;
+
+    /* Make sure that timestamp + diff is always >= 0. Because
+     * of the running time offset this might not be true */
+    if (diff_ < 0 && *timestamp < -diff_)
+      *timestamp = (GstClockTime) - diff_;
+  }
 }
 
 /**
@@ -959,26 +1241,26 @@ gst_event_parse_qos (GstEvent * event, GstQOSType * type,
  *
  * 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. 
+ * configured playback segment can be queried with #GST_QUERY_SEGMENT.
  *
- * @start_type and @stop_type specify how to adjust the currently configured 
+ * @start_type and @stop_type specify how to adjust the currently configured
  * start and stop fields in playback 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. 
+ * 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.
+ * position (if any). If the stop position is updated, it must be different from
+ * -1 (#GST_CLOCK_TIME_NONE) 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. 
+ * #GST_SEEK_TYPE_SET to the desired position.
  *
- * Returns: (transfer full): a new seek event.
+ * Returns: (transfer full) (nullable): a new seek event.
  */
 GstEvent *
 gst_event_new_seek (gdouble rate, GstFormat format, GstSeekFlags flags,
@@ -989,6 +1271,18 @@ gst_event_new_seek (gdouble rate, GstFormat format, GstSeekFlags flags,
 
   g_return_val_if_fail (rate != 0.0, NULL);
 
+  /* SNAP flags only make sense in combination with the KEYUNIT flag. Warn
+   * and unset the SNAP flags if they're set without the KEYUNIT flag */
+  if (!(flags & GST_SEEK_FLAG_KEY_UNIT) &&
+      (flags & (GST_SEEK_FLAG_SNAP_BEFORE | GST_SEEK_FLAG_SNAP_AFTER |
+              GST_SEEK_FLAG_SNAP_NEAREST))) {
+    g_warning ("SNAP seeks only work in combination with the KEY_UNIT "
+        "flag, ignoring SNAP flags");
+    flags &=
+        ~(GST_SEEK_FLAG_SNAP_BEFORE | GST_SEEK_FLAG_SNAP_AFTER |
+        GST_SEEK_FLAG_SNAP_NEAREST);
+  }
+
   if (format == GST_FORMAT_TIME) {
     GST_CAT_INFO (GST_CAT_EVENT,
         "creating seek rate %lf, format TIME, flags %d, "
@@ -1005,14 +1299,16 @@ gst_event_new_seek (gdouble rate, GstFormat format, GstSeekFlags flags,
         stop);
   }
 
-  structure = gst_structure_id_new (GST_QUARK (EVENT_SEEK),
+  structure = gst_structure_new_id (GST_QUARK (EVENT_SEEK),
       GST_QUARK (RATE), G_TYPE_DOUBLE, rate,
       GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
       GST_QUARK (FLAGS), GST_TYPE_SEEK_FLAGS, flags,
       GST_QUARK (CUR_TYPE), GST_TYPE_SEEK_TYPE, start_type,
       GST_QUARK (CUR), G_TYPE_INT64, start,
       GST_QUARK (STOP_TYPE), GST_TYPE_SEEK_TYPE, stop_type,
-      GST_QUARK (STOP), G_TYPE_INT64, stop, NULL);
+      GST_QUARK (STOP), G_TYPE_INT64, stop,
+      GST_QUARK (TRICKMODE_INTERVAL), GST_TYPE_CLOCK_TIME, (GstClockTime) 0,
+      NULL);
   event = gst_event_new_custom (GST_EVENT_SEEK, structure);
 
   return event;
@@ -1025,9 +1321,9 @@ gst_event_new_seek (gdouble rate, GstFormat format, GstSeekFlags flags,
  * @format: (out): result location for the stream format
  * @flags:  (out): result location for the #GstSeekFlags
  * @start_type: (out): result location for the #GstSeekType of the start position
- * @start: (out): result location for the start postion expressed in @format
+ * @start: (out): result location for the start position expressed in @format
  * @stop_type:  (out): result location for the #GstSeekType of the stop position
- * @stop: (out): result location for the stop postion expressed in @format
+ * @stop: (out): result location for the stop position expressed in @format
  *
  * Parses a seek @event and stores the results in the given result locations.
  */
@@ -1073,6 +1369,48 @@ gst_event_parse_seek (GstEvent * event, gdouble * rate,
 }
 
 /**
+ * gst_event_set_seek_trickmode_interval:
+ *
+ * Sets a trickmode interval on a (writable) seek event. Elements
+ * that support TRICKMODE_KEY_UNITS seeks SHOULD use this as the minimal
+ * interval between each frame they may output.
+ *
+ * Since: 1.16
+ */
+void
+gst_event_set_seek_trickmode_interval (GstEvent * event, GstClockTime interval)
+{
+  g_return_if_fail (event != NULL);
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_SEEK);
+  g_return_if_fail (gst_event_is_writable (event));
+  g_return_if_fail (GST_CLOCK_TIME_IS_VALID (interval));
+
+  gst_structure_id_set (GST_EVENT_STRUCTURE (event),
+      GST_QUARK (TRICKMODE_INTERVAL), GST_TYPE_CLOCK_TIME, interval, NULL);
+}
+
+/**
+ * gst_event_parse_seek_trickmode_interval:
+ * @interval: (out)
+ *
+ * Retrieve the trickmode interval that may have been set on a
+ * seek event with gst_event_set_seek_trickmode_interval().
+ *
+ * Since: 1.16
+ */
+void
+gst_event_parse_seek_trickmode_interval (GstEvent * event,
+    GstClockTime * interval)
+{
+  g_return_if_fail (event != NULL);
+  g_return_if_fail (interval != NULL);
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_SEEK);
+
+  gst_structure_id_get (GST_EVENT_STRUCTURE (event),
+      GST_QUARK (TRICKMODE_INTERVAL), GST_TYPE_CLOCK_TIME, interval, NULL);
+}
+
+/**
  * gst_event_new_navigation:
  * @structure: (transfer full): description of the event. The event will take
  *     ownership of the structure.
@@ -1101,8 +1439,6 @@ gst_event_new_navigation (GstStructure * structure)
  * the time format.
  *
  * Returns: (transfer full): a new #GstEvent
- *
- * Since: 0.10.12
  */
 GstEvent *
 gst_event_new_latency (GstClockTime latency)
@@ -1113,7 +1449,7 @@ gst_event_new_latency (GstClockTime latency)
   GST_CAT_INFO (GST_CAT_EVENT,
       "creating latency event %" GST_TIME_FORMAT, GST_TIME_ARGS (latency));
 
-  structure = gst_structure_id_new (GST_QUARK (EVENT_LATENCY),
+  structure = gst_structure_new_id (GST_QUARK (EVENT_LATENCY),
       GST_QUARK (LATENCY), G_TYPE_UINT64, latency, NULL);
   event = gst_event_new_custom (GST_EVENT_LATENCY, structure);
 
@@ -1126,8 +1462,6 @@ gst_event_new_latency (GstClockTime latency)
  * @latency: (out): 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)
@@ -1153,8 +1487,9 @@ gst_event_parse_latency (GstEvent * event, GstClockTime * latency)
  * to skip @amount (expressed in @format) of media. It can be used to implement
  * stepping through the video frame by frame or for doing fast trick modes.
  *
- * A rate of <= 0.0 is not allowed, pause the pipeline or reverse the playback
- * direction of the pipeline to get the same effect.
+ * A rate of <= 0.0 is not allowed. Pause the pipeline, for the effect of rate
+ * = 0.0 or first reverse the direction of playback using a seek event to get
+ * the same effect as rate < 0.0.
  *
  * The @flush flag will clear any pending data in the pipeline before starting
  * the step operation.
@@ -1162,9 +1497,7 @@ gst_event_parse_latency (GstEvent * event, GstClockTime * latency)
  * The @intermediate flag instructs the pipeline that this step operation is
  * part of a larger step operation.
  *
- * Returns: (transfer full): a new #GstEvent
- *
- * Since: 0.10.24
+ * Returns: (transfer full) (nullable): a new #GstEvent
  */
 GstEvent *
 gst_event_new_step (GstFormat format, guint64 amount, gdouble rate,
@@ -1177,7 +1510,7 @@ gst_event_new_step (GstFormat format, guint64 amount, gdouble rate,
 
   GST_CAT_INFO (GST_CAT_EVENT, "creating step event");
 
-  structure = gst_structure_id_new (GST_QUARK (EVENT_STEP),
+  structure = gst_structure_new_id (GST_QUARK (EVENT_STEP),
       GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
       GST_QUARK (AMOUNT), G_TYPE_UINT64, amount,
       GST_QUARK (RATE), G_TYPE_DOUBLE, rate,
@@ -1199,8 +1532,6 @@ gst_event_new_step (GstFormat format, guint64 amount, gdouble rate,
  *     boolean in
  *
  * Parse the step event.
- *
- * Since: 0.10.24
  */
 void
 gst_event_parse_step (GstEvent * event, GstFormat * format, guint64 * amount,
@@ -1233,14 +1564,12 @@ gst_event_parse_step (GstEvent * event, GstFormat * format, guint64 * amount,
 /**
  * gst_event_new_reconfigure:
 
- * Create a new reconfigure event. The purpose of the reconfingure event is
+ * Create a new reconfigure event. The purpose of the reconfigure event is
  * to travel upstream and make elements renegotiate their caps or reconfigure
  * their buffer pools. This is useful when changing properties on elements
  * or changing the topology of the pipeline.
  *
  * Returns: (transfer full): a new #GstEvent
- *
- * Since: 0.11.0
  */
 GstEvent *
 gst_event_new_reconfigure (void)
@@ -1256,19 +1585,20 @@ gst_event_new_reconfigure (void)
 
 /**
  * gst_event_new_sink_message:
+ * @name: a name for the event
  * @msg: (transfer none): the #GstMessage to be posted
  *
  * Create a new sink-message event. The purpose of the sink-message event is
  * to instruct a sink to post the message contained in the event synchronized
  * with the stream.
  *
- * Returns: (transfer full): a new #GstEvent
+ * @name is used to store multiple sticky events on one pad.
  *
- * Since: 0.10.26
+ * Returns: (transfer full): a new #GstEvent
  */
-/* FIXME 0.11: take ownership of msg for consistency? */
+/* FIXME 2.0: take ownership of msg for consistency? */
 GstEvent *
-gst_event_new_sink_message (GstMessage * msg)
+gst_event_new_sink_message (const gchar * name, GstMessage * msg)
 {
   GstEvent *event;
   GstStructure *structure;
@@ -1277,7 +1607,7 @@ gst_event_new_sink_message (GstMessage * msg)
 
   GST_CAT_INFO (GST_CAT_EVENT, "creating sink-message event");
 
-  structure = gst_structure_id_new (GST_QUARK (EVENT_SINK_MESSAGE),
+  structure = gst_structure_new_id (g_quark_from_string (name),
       GST_QUARK (MESSAGE), GST_TYPE_MESSAGE, msg, NULL);
   event = gst_event_new_custom (GST_EVENT_SINK_MESSAGE, structure);
 
@@ -1290,8 +1620,6 @@ gst_event_new_sink_message (GstMessage * msg)
  * @msg: (out) (transfer full): a pointer to store the #GstMessage in.
  *
  * Parse the sink-message event. Unref @msg after usage.
- *
- * Since: 0.10.26
  */
 void
 gst_event_parse_sink_message (GstEvent * event, GstMessage ** msg)
@@ -1307,3 +1635,535 @@ gst_event_parse_sink_message (GstEvent * event, GstMessage ** msg)
         GST_MESSAGE (g_value_dup_boxed (gst_structure_id_get_value
             (structure, GST_QUARK (MESSAGE))));
 }
+
+/**
+ * gst_event_new_stream_start:
+ * @stream_id: Identifier for this stream
+ *
+ * Create a new STREAM_START event. The stream start event can only
+ * travel downstream synchronized with the buffer flow. It is expected
+ * to be the first event that is sent for a new stream.
+ *
+ * Source elements, demuxers and other elements that create new streams
+ * are supposed to send this event as the first event of a new stream. It
+ * should not be sent after a flushing seek or in similar situations
+ * and is used to mark the beginning of a new logical stream. Elements
+ * combining multiple streams must ensure that this event is only forwarded
+ * downstream once and not for every single input stream.
+ *
+ * The @stream_id should be a unique string that consists of the upstream
+ * stream-id, / as separator and a unique stream-id for this specific
+ * stream. A new stream-id should only be created for a stream if the upstream
+ * stream is split into (potentially) multiple new streams, e.g. in a demuxer,
+ * but not for every single element in the pipeline.
+ * gst_pad_create_stream_id() or gst_pad_create_stream_id_printf() can be
+ * used to create a stream-id.  There are no particular semantics for the
+ * stream-id, though it should be deterministic (to support stream matching)
+ * and it might be used to order streams (besides any information conveyed by
+ * stream flags).
+ *
+ * Returns: (transfer full): the new STREAM_START event.
+ */
+GstEvent *
+gst_event_new_stream_start (const gchar * stream_id)
+{
+  GstStructure *s;
+
+  g_return_val_if_fail (stream_id != NULL, NULL);
+
+  s = gst_structure_new_id (GST_QUARK (EVENT_STREAM_START),
+      GST_QUARK (STREAM_ID), G_TYPE_STRING, stream_id,
+      GST_QUARK (FLAGS), GST_TYPE_STREAM_FLAGS, GST_STREAM_FLAG_NONE, NULL);
+
+  return gst_event_new_custom (GST_EVENT_STREAM_START, s);
+}
+
+/**
+ * gst_event_parse_stream_start:
+ * @event: a stream-start event.
+ * @stream_id: (out) (transfer none): pointer to store the stream-id
+ *
+ * Parse a stream-id @event and store the result in the given @stream_id
+ * location. The string stored in @stream_id must not be modified and will
+ * remain valid only until @event gets freed. Make a copy if you want to
+ * modify it or store it for later use.
+ */
+void
+gst_event_parse_stream_start (GstEvent * event, const gchar ** stream_id)
+{
+  const GstStructure *structure;
+  const GValue *val;
+
+  g_return_if_fail (event != NULL);
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_STREAM_START);
+
+  structure = gst_event_get_structure (event);
+  val = gst_structure_id_get_value (structure, GST_QUARK (STREAM_ID));
+
+  if (stream_id)
+    *stream_id = g_value_get_string (val);
+}
+
+/**
+ * gst_event_set_stream:
+ * @event: a stream-start event
+ * @stream: (transfer none): the stream object to set
+ *
+ * Set the @stream on the stream-start @event
+ *
+ * Since: 1.10
+ */
+void
+gst_event_set_stream (GstEvent * event, GstStream * stream)
+{
+  g_return_if_fail (event != NULL);
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_STREAM_START);
+  g_return_if_fail (gst_event_is_writable (event));
+
+  gst_structure_id_set (GST_EVENT_STRUCTURE (event),
+      GST_QUARK (STREAM), GST_TYPE_STREAM, stream, NULL);
+}
+
+/**
+ * gst_event_parse_stream:
+ * @event: a stream-start event
+ * @stream: (out) (transfer full): address of variable to store the stream
+ *
+ * Parse a stream-start @event and extract the #GstStream from it.
+ *
+ * Since: 1.10
+ */
+void
+gst_event_parse_stream (GstEvent * event, GstStream ** stream)
+{
+  g_return_if_fail (event != NULL);
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_STREAM_START);
+
+  if (stream) {
+    gst_structure_id_get (GST_EVENT_STRUCTURE (event),
+        GST_QUARK (STREAM), GST_TYPE_STREAM, stream, NULL);
+  }
+
+}
+
+/**
+ * gst_event_set_stream_flags:
+ * @event: a stream-start event
+ * @flags: the stream flags to set
+ *
+ * Since: 1.2
+ */
+void
+gst_event_set_stream_flags (GstEvent * event, GstStreamFlags flags)
+{
+  g_return_if_fail (event != NULL);
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_STREAM_START);
+  g_return_if_fail (gst_event_is_writable (event));
+
+  gst_structure_id_set (GST_EVENT_STRUCTURE (event),
+      GST_QUARK (FLAGS), GST_TYPE_STREAM_FLAGS, flags, NULL);
+}
+
+/**
+ * gst_event_parse_stream_flags:
+ * @event: a stream-start event
+ * @flags: (out): address of variable where to store the stream flags
+ *
+ * Since: 1.2
+ */
+void
+gst_event_parse_stream_flags (GstEvent * event, GstStreamFlags * flags)
+{
+  g_return_if_fail (event != NULL);
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_STREAM_START);
+
+  if (flags) {
+    gst_structure_id_get (GST_EVENT_STRUCTURE (event),
+        GST_QUARK (FLAGS), GST_TYPE_STREAM_FLAGS, flags, NULL);
+  }
+}
+
+/**
+ * gst_event_set_group_id:
+ * @event: a stream-start event
+ * @group_id: the group id to set
+ *
+ * All streams that have the same group id are supposed to be played
+ * together, i.e. all streams inside a container file should have the
+ * same group id but different stream ids. The group id should change
+ * each time the stream is started, resulting in different group ids
+ * each time a file is played for example.
+ *
+ * Use gst_util_group_id_next() to get a new group id.
+ *
+ * Since: 1.2
+ */
+void
+gst_event_set_group_id (GstEvent * event, guint group_id)
+{
+  g_return_if_fail (event != NULL);
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_STREAM_START);
+  g_return_if_fail (gst_event_is_writable (event));
+
+  gst_structure_id_set (GST_EVENT_STRUCTURE (event),
+      GST_QUARK (GROUP_ID), G_TYPE_UINT, group_id, NULL);
+}
+
+/**
+ * gst_event_parse_group_id:
+ * @event: a stream-start event
+ * @group_id: (out): address of variable where to store the group id
+ *
+ * Returns: %TRUE if a group id was set on the event and could be parsed,
+ *   %FALSE otherwise.
+ *
+ * Since: 1.2
+ */
+gboolean
+gst_event_parse_group_id (GstEvent * event, guint * group_id)
+{
+  g_return_val_if_fail (event != NULL, FALSE);
+  g_return_val_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_STREAM_START,
+      FALSE);
+
+  if (group_id) {
+    return gst_structure_id_get (GST_EVENT_STRUCTURE (event),
+        GST_QUARK (GROUP_ID), G_TYPE_UINT, group_id, NULL);
+  }
+
+  return TRUE;
+}
+
+/**
+ * gst_event_new_stream_collection:
+ * @collection: Active collection for this data flow
+ *
+ * Create a new STREAM_COLLECTION event. The stream collection event can only
+ * travel downstream synchronized with the buffer flow.
+ *
+ * Source elements, demuxers and other elements that manage collections
+ * of streams and post #GstStreamCollection messages on the bus also send
+ * this event downstream on each pad involved in the collection, so that
+ * activation of a new collection can be tracked through the downstream
+ * data flow.
+ *
+ * Returns: (transfer full): the new STREAM_COLLECTION event.
+ *
+ * Since: 1.10
+ */
+GstEvent *
+gst_event_new_stream_collection (GstStreamCollection * collection)
+{
+  GstStructure *s;
+
+  g_return_val_if_fail (collection != NULL, NULL);
+  g_return_val_if_fail (GST_IS_STREAM_COLLECTION (collection), NULL);
+
+  s = gst_structure_new_id (GST_QUARK (EVENT_STREAM_COLLECTION),
+      GST_QUARK (COLLECTION), GST_TYPE_STREAM_COLLECTION, collection, NULL);
+
+  return gst_event_new_custom (GST_EVENT_STREAM_COLLECTION, s);
+}
+
+/**
+ * gst_event_parse_stream_collection:
+ * @event: a stream-collection event
+ * @collection: (out): pointer to store the collection
+ *
+ * Retrieve new #GstStreamCollection from STREAM_COLLECTION event @event.
+ *
+ * Since: 1.10
+ */
+void
+gst_event_parse_stream_collection (GstEvent * event,
+    GstStreamCollection ** collection)
+{
+  const GstStructure *structure;
+
+  g_return_if_fail (event != NULL);
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_STREAM_COLLECTION);
+
+  structure = gst_event_get_structure (event);
+
+  if (collection) {
+    gst_structure_id_get (structure,
+        GST_QUARK (COLLECTION), GST_TYPE_STREAM_COLLECTION, collection, NULL);
+  }
+}
+
+/**
+ * gst_event_new_toc:
+ * @toc: (transfer none): #GstToc structure.
+ * @updated: whether @toc was updated or not.
+ *
+ * Generate a TOC event from the given @toc. The purpose of the TOC event is to
+ * inform elements that some kind of the TOC was found.
+ *
+ * Returns: (transfer full): a new #GstEvent.
+ */
+GstEvent *
+gst_event_new_toc (GstToc * toc, gboolean updated)
+{
+  GstStructure *toc_struct;
+  GQuark id;
+
+  g_return_val_if_fail (toc != NULL, NULL);
+
+  GST_CAT_INFO (GST_CAT_EVENT, "creating toc event");
+
+  /* need different structure names so sticky_multi event stuff on pads
+   * works, i.e. both TOC events are kept around */
+  if (gst_toc_get_scope (toc) == GST_TOC_SCOPE_GLOBAL)
+    id = GST_QUARK (EVENT_TOC_GLOBAL);
+  else
+    id = GST_QUARK (EVENT_TOC_CURRENT);
+
+  toc_struct = gst_structure_new_id (id,
+      GST_QUARK (TOC), GST_TYPE_TOC, toc,
+      GST_QUARK (UPDATED), G_TYPE_BOOLEAN, updated, NULL);
+
+  return gst_event_new_custom (GST_EVENT_TOC, toc_struct);
+}
+
+/**
+ * gst_event_parse_toc:
+ * @event: a TOC event.
+ * @toc: (out) (transfer full): pointer to #GstToc structure.
+ * @updated: (out): pointer to store TOC updated flag.
+ *
+ * Parse a TOC @event and store the results in the given @toc and @updated locations.
+ */
+void
+gst_event_parse_toc (GstEvent * event, GstToc ** toc, gboolean * updated)
+{
+  const GstStructure *structure;
+
+  g_return_if_fail (event != NULL);
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_TOC);
+  g_return_if_fail (toc != NULL);
+
+  structure = gst_event_get_structure (event);
+
+  gst_structure_id_get (structure,
+      GST_QUARK (TOC), GST_TYPE_TOC, toc,
+      GST_QUARK (UPDATED), G_TYPE_BOOLEAN, updated, NULL);
+}
+
+/**
+ * gst_event_new_toc_select:
+ * @uid: UID in the TOC to start playback from.
+ *
+ * Generate a TOC select event with the given @uid. The purpose of the
+ * TOC select event is to start playback based on the TOC's entry with the
+ * given @uid.
+ *
+ * Returns: a new #GstEvent.
+ */
+GstEvent *
+gst_event_new_toc_select (const gchar * uid)
+{
+  GstStructure *structure;
+
+  g_return_val_if_fail (uid != NULL, NULL);
+
+  GST_CAT_INFO (GST_CAT_EVENT, "creating toc select event for UID: %s", uid);
+
+  structure = gst_structure_new_id (GST_QUARK (EVENT_TOC_SELECT),
+      GST_QUARK (UID), G_TYPE_STRING, uid, NULL);
+
+  return gst_event_new_custom (GST_EVENT_TOC_SELECT, structure);
+}
+
+/**
+ * gst_event_parse_toc_select:
+ * @event: a TOC select event.
+ * @uid: (out) (transfer full) (allow-none): storage for the selection UID.
+ *
+ * Parse a TOC select @event and store the results in the given @uid location.
+ */
+void
+gst_event_parse_toc_select (GstEvent * event, gchar ** uid)
+{
+  const GstStructure *structure;
+  const GValue *val;
+
+  g_return_if_fail (event != NULL);
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_TOC_SELECT);
+
+  structure = gst_event_get_structure (event);
+  val = gst_structure_id_get_value (structure, GST_QUARK (UID));
+
+  if (uid != NULL)
+    *uid = g_strdup (g_value_get_string (val));
+
+}
+
+/**
+ * gst_event_new_protection:
+ * @system_id: (transfer none): a string holding a UUID that uniquely
+ * identifies a protection system.
+ * @data: (transfer none): a #GstBuffer holding protection system specific
+ * information. The reference count of the buffer will be incremented by one.
+ * @origin: a string indicating where the protection
+ * information carried in the event was extracted from. The allowed values
+ * of this string will depend upon the protection scheme.
+ *
+ * Creates a new event containing information specific to a particular
+ * protection system (uniquely identified by @system_id), by which that
+ * protection system can acquire key(s) to decrypt a protected stream.
+ *
+ * In order for a decryption element to decrypt media
+ * protected using a specific system, it first needs all the
+ * protection system specific information necessary to acquire the decryption
+ * key(s) for that stream. The functions defined here enable this information
+ * to be passed in events from elements that extract it
+ * (e.g., ISOBMFF demuxers, MPEG DASH demuxers) to protection decrypter
+ * elements that use it.
+ *
+ * Events containing protection system specific information are created using
+ * #gst_event_new_protection, and they can be parsed by downstream elements
+ * using #gst_event_parse_protection.
+ *
+ * In Common Encryption, protection system specific information may be located
+ * within ISOBMFF files, both in movie (moov) boxes and movie fragment (moof)
+ * boxes; it may also be contained in ContentProtection elements within MPEG
+ * DASH MPDs. The events created by #gst_event_new_protection contain data
+ * identifying from which of these locations the encapsulated protection system
+ * specific information originated. This origin information is required as
+ * some protection systems use different encodings depending upon where the
+ * information originates.
+ *
+ * The events returned by gst_event_new_protection() are implemented
+ * in such a way as to ensure that the most recently-pushed protection info
+ * event of a particular @origin and @system_id will
+ * be stuck to the output pad of the sending element.
+ *
+ * Returns: a #GST_EVENT_PROTECTION event, if successful; %NULL
+ * if unsuccessful.
+ *
+ * Since: 1.6
+ */
+GstEvent *
+gst_event_new_protection (const gchar * system_id,
+    GstBuffer * data, const gchar * origin)
+{
+  gchar *event_name;
+  GstEvent *event;
+  GstStructure *s;
+
+  g_return_val_if_fail (system_id != NULL, NULL);
+  g_return_val_if_fail (data != NULL, NULL);
+
+  event_name =
+      g_strconcat ("GstProtectionEvent", origin ? "-" : "",
+      origin ? origin : "", "-", system_id, NULL);
+
+  GST_CAT_INFO (GST_CAT_EVENT, "creating protection event %s", event_name);
+
+  s = gst_structure_new (event_name, "data", GST_TYPE_BUFFER, data,
+      "system_id", G_TYPE_STRING, system_id, NULL);
+  if (origin)
+    gst_structure_set (s, "origin", G_TYPE_STRING, origin, NULL);
+  event = gst_event_new_custom (GST_EVENT_PROTECTION, s);
+
+  g_free (event_name);
+  return event;
+}
+
+/**
+ * gst_event_parse_protection:
+ * @event: a #GST_EVENT_PROTECTION event.
+ * @system_id: (out) (allow-none) (transfer none): pointer to store the UUID
+ * string uniquely identifying a content protection system.
+ * @data: (out) (allow-none) (transfer none): pointer to store a #GstBuffer
+ * holding protection system specific information.
+ * @origin: (out) (allow-none) (transfer none): pointer to store a value that
+ * indicates where the protection information carried by @event was extracted
+ * from.
+ *
+ * Parses an event containing protection system specific information and stores
+ * the results in @system_id, @data and @origin. The data stored in @system_id,
+ * @origin and @data are valid until @event is released.
+ *
+ * Since: 1.6
+ */
+void
+gst_event_parse_protection (GstEvent * event, const gchar ** system_id,
+    GstBuffer ** data, const gchar ** origin)
+{
+  const GstStructure *s;
+
+  g_return_if_fail (event != NULL);
+  g_return_if_fail (GST_IS_EVENT (event));
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_PROTECTION);
+
+  s = gst_event_get_structure (event);
+
+  if (origin)
+    *origin = gst_structure_get_string (s, "origin");
+
+  if (system_id)
+    *system_id = gst_structure_get_string (s, "system_id");
+
+  if (data) {
+    const GValue *value = gst_structure_get_value (s, "data");
+    *data = gst_value_get_buffer (value);
+  }
+}
+
+/**
+ * gst_event_new_segment_done:
+ * @format: The format of the position being done
+ * @position: The position of the segment being done
+ *
+ * Create a new segment-done event. This event is sent by elements that
+ * finish playback of a segment as a result of a segment seek.
+ *
+ * Returns: (transfer full): a new #GstEvent
+ */
+GstEvent *
+gst_event_new_segment_done (GstFormat format, gint64 position)
+{
+  GstEvent *event;
+  GstStructure *structure;
+
+  GST_CAT_INFO (GST_CAT_EVENT, "creating segment-done event");
+
+  structure = gst_structure_new_id (GST_QUARK (EVENT_SEGMENT_DONE),
+      GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
+      GST_QUARK (POSITION), G_TYPE_INT64, position, NULL);
+
+  event = gst_event_new_custom (GST_EVENT_SEGMENT_DONE, structure);
+
+  return event;
+}
+
+/**
+ * gst_event_parse_segment_done:
+ * @event: A valid #GstEvent of type GST_EVENT_SEGMENT_DONE.
+ * @format: (out) (allow-none): Result location for the format, or %NULL
+ * @position: (out) (allow-none): Result location for the position, or %NULL
+ *
+ * Extracts the position and format from the segment done message.
+ *
+ */
+void
+gst_event_parse_segment_done (GstEvent * event, GstFormat * format,
+    gint64 * position)
+{
+  const GstStructure *structure;
+  const GValue *val;
+
+  g_return_if_fail (event != NULL);
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_SEGMENT_DONE);
+
+  structure = gst_event_get_structure (event);
+
+  val = gst_structure_id_get_value (structure, GST_QUARK (FORMAT));
+  if (format != NULL)
+    *format = g_value_get_enum (val);
+
+  val = gst_structure_id_get_value (structure, GST_QUARK (POSITION));
+  if (position != NULL)
+    *position = g_value_get_int64 (val);
+}