gstreamer/gst-libs/gst/video/video-event.c

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/* GStreamer
* Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
* Library <2002> Ronald Bultje <rbultje@ronald.bitfreak.net>
* Copyright (C) 2007 David A. Schleef <ds@schleef.org>
*
* 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., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "video-event.h"
#define GST_VIDEO_EVENT_STILL_STATE_NAME "GstEventStillFrame"
/**
* gst_video_event_new_still_frame:
* @in_still: boolean value for the still-frame state of the event.
*
* Creates a new Still Frame event. If @in_still is %TRUE, then the event
* represents the start of a still frame sequence. If it is %FALSE, then
* the event ends a still frame sequence.
*
* To parse an event created by gst_video_event_new_still_frame() use
* gst_video_event_parse_still_frame().
*
* Returns: The new GstEvent
*/
GstEvent *
gst_video_event_new_still_frame (gboolean in_still)
{
GstEvent *still_event;
GstStructure *s;
s = gst_structure_new (GST_VIDEO_EVENT_STILL_STATE_NAME,
"still-state", G_TYPE_BOOLEAN, in_still, NULL);
still_event = gst_event_new_custom (GST_EVENT_CUSTOM_DOWNSTREAM, s);
return still_event;
}
/**
* gst_video_event_parse_still_frame:
* @event: A #GstEvent to parse
* @in_still: (out):
* A boolean to receive the still-frame status from the event, or NULL
*
* Parse a #GstEvent, identify if it is a Still Frame event, and
* return the still-frame state from the event if it is.
* If the event represents the start of a still frame, the in_still
* variable will be set to TRUE, otherwise FALSE. It is OK to pass NULL for the
* in_still variable order to just check whether the event is a valid still-frame
* event.
*
* Create a still frame event using gst_video_event_new_still_frame()
*
* Returns: %TRUE if the event is a valid still-frame event. %FALSE if not
*/
gboolean
gst_video_event_parse_still_frame (GstEvent * event, gboolean * in_still)
{
const GstStructure *s;
gboolean ev_still_state;
g_return_val_if_fail (event != NULL, FALSE);
if (GST_EVENT_TYPE (event) != GST_EVENT_CUSTOM_DOWNSTREAM)
return FALSE; /* Not a still frame event */
s = gst_event_get_structure (event);
if (s == NULL
|| !gst_structure_has_name (s, GST_VIDEO_EVENT_STILL_STATE_NAME))
return FALSE; /* Not a still frame event */
if (!gst_structure_get_boolean (s, "still-state", &ev_still_state))
return FALSE; /* Not a still frame event */
if (in_still)
*in_still = ev_still_state;
return TRUE;
}
#define GST_VIDEO_EVENT_FORCE_KEY_UNIT_NAME "GstForceKeyUnit"
/**
* gst_video_event_new_downstream_force_key_unit:
* @timestamp: the timestamp of the buffer that starts a new key unit
* @stream_time: the stream_time of the buffer that starts a new key unit
* @running_time: the running_time of the buffer that starts a new key unit
* @all_headers: %TRUE to produce headers when starting a new key unit
* @count: integer that can be used to number key units
*
* Creates a new downstream force key unit event. A downstream force key unit
* event can be sent down the pipeline to request downstream elements to produce
* a key unit. A downstream force key unit event must also be sent when handling
* an upstream force key unit event to notify downstream that the latter has been
* handled.
*
* To parse an event created by gst_video_event_new_downstream_force_key_unit() use
* gst_video_event_parse_downstream_force_key_unit().
*
* Returns: The new GstEvent
*/
GstEvent *
gst_video_event_new_downstream_force_key_unit (GstClockTime timestamp,
GstClockTime stream_time, GstClockTime running_time, gboolean all_headers,
guint count)
{
GstEvent *force_key_unit_event;
GstStructure *s;
s = gst_structure_new (GST_VIDEO_EVENT_FORCE_KEY_UNIT_NAME,
"timestamp", G_TYPE_UINT64, timestamp,
"stream-time", G_TYPE_UINT64, stream_time,
"running-time", G_TYPE_UINT64, running_time,
"all-headers", G_TYPE_BOOLEAN, all_headers,
"count", G_TYPE_UINT, count, NULL);
force_key_unit_event = gst_event_new_custom (GST_EVENT_CUSTOM_DOWNSTREAM, s);
return force_key_unit_event;
}
/**
* gst_video_event_new_upstream_force_key_unit:
* @running_time: the running_time at which a new key unit should be produced
* @all_headers: %TRUE to produce headers when starting a new key unit
* @count: integer that can be used to number key units
*
* Creates a new upstream force key unit event. An upstream force key unit event
* can be sent to request upstream elements to produce a key unit.
*
* @running_time can be set to request a new key unit at a specific
* running_time. If set to GST_CLOCK_TIME_NONE, upstream elements will produce a
* new key unit as soon as possible.
*
* To parse an event created by gst_video_event_new_downstream_force_key_unit() use
* gst_video_event_parse_downstream_force_key_unit().
*
* Returns: The new GstEvent
*/
GstEvent *
gst_video_event_new_upstream_force_key_unit (GstClockTime running_time,
gboolean all_headers, guint count)
{
GstEvent *force_key_unit_event;
GstStructure *s;
s = gst_structure_new (GST_VIDEO_EVENT_FORCE_KEY_UNIT_NAME,
"running-time", GST_TYPE_CLOCK_TIME, running_time,
"all-headers", G_TYPE_BOOLEAN, all_headers,
"count", G_TYPE_UINT, count, NULL);
force_key_unit_event = gst_event_new_custom (GST_EVENT_CUSTOM_UPSTREAM, s);
return force_key_unit_event;
}
/**
* gst_video_event_is_force_key_unit:
* @event: A #GstEvent to check
*
* Checks if an event is a force key unit event. Returns true for both upstream
* and downstream force key unit events.
*
* Returns: %TRUE if the event is a valid force key unit event
*/
gboolean
gst_video_event_is_force_key_unit (GstEvent * event)
{
const GstStructure *s;
g_return_val_if_fail (event != NULL, FALSE);
if (GST_EVENT_TYPE (event) != GST_EVENT_CUSTOM_DOWNSTREAM &&
GST_EVENT_TYPE (event) != GST_EVENT_CUSTOM_UPSTREAM)
return FALSE; /* Not a force key unit event */
s = gst_event_get_structure (event);
if (s == NULL
|| !gst_structure_has_name (s, GST_VIDEO_EVENT_FORCE_KEY_UNIT_NAME))
return FALSE;
return TRUE;
}
/**
* gst_video_event_parse_downstream_force_key_unit:
* @event: A #GstEvent to parse
* @timestamp: (out): A pointer to the timestamp in the event
* @stream_time: (out): A pointer to the stream-time in the event
* @running_time: (out): A pointer to the running-time in the event
* @all_headers: (out): A pointer to the all_headers flag in the event
* @count: (out): A pointer to the count field of the event
*
* Get timestamp, stream-time, running-time, all-headers and count in the force
* key unit event. See gst_video_event_new_downstream_force_key_unit() for a
* full description of the downstream force key unit event.
*
* @running_time will be adjusted for any pad offsets of pads it was passing through.
*
* Returns: %TRUE if the event is a valid downstream force key unit event.
*/
gboolean
gst_video_event_parse_downstream_force_key_unit (GstEvent * event,
GstClockTime * timestamp, GstClockTime * stream_time,
GstClockTime * running_time, gboolean * all_headers, guint * count)
{
const GstStructure *s;
GstClockTime ev_timestamp, ev_stream_time, ev_running_time;
gboolean ev_all_headers;
guint ev_count;
g_return_val_if_fail (event != NULL, FALSE);
if (GST_EVENT_TYPE (event) != GST_EVENT_CUSTOM_DOWNSTREAM)
return FALSE; /* Not a force key unit event */
s = gst_event_get_structure (event);
if (s == NULL
|| !gst_structure_has_name (s, GST_VIDEO_EVENT_FORCE_KEY_UNIT_NAME))
return FALSE;
if (!gst_structure_get_clock_time (s, "timestamp", &ev_timestamp))
ev_timestamp = GST_CLOCK_TIME_NONE;
if (!gst_structure_get_clock_time (s, "stream-time", &ev_stream_time))
ev_stream_time = GST_CLOCK_TIME_NONE;
if (!gst_structure_get_clock_time (s, "running-time", &ev_running_time))
ev_running_time = GST_CLOCK_TIME_NONE;
if (!gst_structure_get_boolean (s, "all-headers", &ev_all_headers))
ev_all_headers = FALSE;
if (!gst_structure_get_uint (s, "count", &ev_count))
ev_count = 0;
if (timestamp)
*timestamp = ev_timestamp;
if (stream_time)
*stream_time = ev_stream_time;
if (running_time) {
gint64 offset = gst_event_get_running_time_offset (event);
*running_time = ev_running_time;
/* Catch underflows */
if (*running_time > -offset)
*running_time += offset;
else
*running_time = 0;
}
if (all_headers)
*all_headers = ev_all_headers;
if (count)
*count = ev_count;
return TRUE;
}
/**
* gst_video_event_parse_upstream_force_key_unit:
* @event: A #GstEvent to parse
* @running_time: (out): A pointer to the running_time in the event
* @all_headers: (out): A pointer to the all_headers flag in the event
* @count: (out): A pointer to the count field in the event
*
* Get running-time, all-headers and count in the force key unit event. See
* gst_video_event_new_upstream_force_key_unit() for a full description of the
* upstream force key unit event.
*
* Create an upstream force key unit event using gst_video_event_new_upstream_force_key_unit()
*
* @running_time will be adjusted for any pad offsets of pads it was passing through.
*
* Returns: %TRUE if the event is a valid upstream force-key-unit event. %FALSE if not
*/
gboolean
gst_video_event_parse_upstream_force_key_unit (GstEvent * event,
GstClockTime * running_time, gboolean * all_headers, guint * count)
{
const GstStructure *s;
GstClockTime ev_running_time;
gboolean ev_all_headers;
guint ev_count;
g_return_val_if_fail (event != NULL, FALSE);
if (GST_EVENT_TYPE (event) != GST_EVENT_CUSTOM_UPSTREAM)
return FALSE; /* Not a force key unit event */
s = gst_event_get_structure (event);
if (s == NULL
|| !gst_structure_has_name (s, GST_VIDEO_EVENT_FORCE_KEY_UNIT_NAME))
return FALSE;
if (!gst_structure_get_clock_time (s, "running-time", &ev_running_time))
ev_running_time = GST_CLOCK_TIME_NONE;
if (!gst_structure_get_boolean (s, "all-headers", &ev_all_headers))
ev_all_headers = FALSE;
if (!gst_structure_get_uint (s, "count", &ev_count))
ev_count = 0;
if (running_time) {
gint64 offset = gst_event_get_running_time_offset (event);
*running_time = ev_running_time;
/* Catch underflows */
if (*running_time > -offset)
*running_time += offset;
else
*running_time = 0;
}
if (all_headers)
*all_headers = ev_all_headers;
if (count)
*count = ev_count;
return TRUE;
}