gstreamer/gst/gstpipeline.c
Evan Nemerson 6c6bb0e217 introspection: assorted introspection and documentation fixes
These changes are to clean up syntax issues such as missing colons,
missing spaces, etc., and minor issues such as argument names in
headers not matching the implementation and/or documentation.
2012-06-18 13:11:40 +02:00

850 lines
26 KiB
C

/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2004,2005 Wim Taymans <wim@fluendo.com>
*
* gstpipeline.c: Overall pipeline management element
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION:gstpipeline
* @short_description: Top-level bin with clocking and bus management
functionality.
* @see_also: #GstElement, #GstBin, #GstClock, #GstBus
*
* A #GstPipeline is a special #GstBin used as the toplevel container for
* the filter graph. The #GstPipeline will manage the selection and
* distribution of a global #GstClock as well as provide a #GstBus to the
* application.
*
* gst_pipeline_new() is used to create a pipeline. when you are done with
* the pipeline, use gst_object_unref() to free its resources including all
* added #GstElement objects (if not otherwise referenced).
*
* Elements are added and removed from the pipeline using the #GstBin
* methods like gst_bin_add() and gst_bin_remove() (see #GstBin).
*
* Before changing the state of the #GstPipeline (see #GstElement) a #GstBus
* can be retrieved with gst_pipeline_get_bus(). This bus can then be
* used to receive #GstMessage from the elements in the pipeline.
*
* By default, a #GstPipeline will automatically flush the pending #GstBus
* messages when going to the NULL state to ensure that no circular
* references exist when no messages are read from the #GstBus. This
* behaviour can be changed with gst_pipeline_set_auto_flush_bus().
*
* When the #GstPipeline performs the PAUSED to PLAYING state change it will
* select a clock for the elements. The clock selection algorithm will by
* default select a clock provided by an element that is most upstream
* (closest to the source). For live pipelines (ones that return
* #GST_STATE_CHANGE_NO_PREROLL from the gst_element_set_state() call) this
* will select the clock provided by the live source. For normal pipelines
* this will select a clock provided by the sinks (most likely the audio
* sink). If no element provides a clock, a default #GstSystemClock is used.
*
* The clock selection can be controlled with the gst_pipeline_use_clock()
* method, which will enforce a given clock on the pipeline. With
* gst_pipeline_auto_clock() the default clock selection algorithm can be
* restored.
*
* A #GstPipeline maintains a running time for the elements. The running
* time is defined as the difference between the current clock time and
* the base time. When the pipeline goes to READY or a flushing seek is
* performed on it, the running time is reset to 0. When the pipeline is
* set from PLAYING to PAUSED, the current clock time is sampled and used to
* configure the base time for the elements when the pipeline is set
* to PLAYING again. The effect is that the running time (as the difference
* between the clock time and the base time) will count how much time was spent
* in the PLAYING state. This default behaviour can be changed with the
* gst_element_set_start_time() method.
*
* Last reviewed on 2012-03-29 (0.11.3)
*/
#include "gst_private.h"
#include "gsterror.h"
#include "gst-i18n-lib.h"
#include "gstpipeline.h"
#include "gstinfo.h"
#include "gstsystemclock.h"
#include "gstutils.h"
GST_DEBUG_CATEGORY_STATIC (pipeline_debug);
#define GST_CAT_DEFAULT pipeline_debug
/* Pipeline signals and args */
enum
{
/* FILL ME */
LAST_SIGNAL
};
#define DEFAULT_DELAY 0
#define DEFAULT_AUTO_FLUSH_BUS TRUE
enum
{
PROP_0,
PROP_DELAY,
PROP_AUTO_FLUSH_BUS
};
#define GST_PIPELINE_GET_PRIVATE(obj) \
(G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_PIPELINE, GstPipelinePrivate))
struct _GstPipelinePrivate
{
/* with LOCK */
gboolean auto_flush_bus;
/* when we need to update stream_time or clock when going back to
* PLAYING*/
GstClockTime last_start_time;
gboolean update_clock;
};
static void gst_pipeline_dispose (GObject * object);
static void gst_pipeline_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_pipeline_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static GstClock *gst_pipeline_provide_clock_func (GstElement * element);
static GstStateChangeReturn gst_pipeline_change_state (GstElement * element,
GstStateChange transition);
static void gst_pipeline_handle_message (GstBin * bin, GstMessage * message);
/* static guint gst_pipeline_signals[LAST_SIGNAL] = { 0 }; */
#define _do_init \
{ \
GST_DEBUG_CATEGORY_INIT (pipeline_debug, "pipeline", GST_DEBUG_BOLD, \
"debugging info for the 'pipeline' container element"); \
}
#define gst_pipeline_parent_class parent_class
G_DEFINE_TYPE_WITH_CODE (GstPipeline, gst_pipeline, GST_TYPE_BIN, _do_init);
static void
gst_pipeline_class_init (GstPipelineClass * klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
GstBinClass *gstbin_class = GST_BIN_CLASS (klass);
g_type_class_add_private (klass, sizeof (GstPipelinePrivate));
gobject_class->set_property = gst_pipeline_set_property;
gobject_class->get_property = gst_pipeline_get_property;
/**
* GstPipeline:delay:
*
* The expected delay needed for elements to spin up to the
* PLAYING state expressed in nanoseconds.
* see gst_pipeline_set_delay() for more information on this option.
*
* Since: 0.10.5
**/
g_object_class_install_property (gobject_class, PROP_DELAY,
g_param_spec_uint64 ("delay", "Delay",
"Expected delay needed for elements "
"to spin up to PLAYING in nanoseconds", 0, G_MAXUINT64, DEFAULT_DELAY,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
/**
* GstPipeline:auto-flush-bus:
*
* Whether or not to automatically flush all messages on the
* pipeline's bus when going from READY to NULL state. Please see
* gst_pipeline_set_auto_flush_bus() for more information on this option.
*
* Since: 0.10.4
**/
g_object_class_install_property (gobject_class, PROP_AUTO_FLUSH_BUS,
g_param_spec_boolean ("auto-flush-bus", "Auto Flush Bus",
"Whether to automatically flush the pipeline's bus when going "
"from READY into NULL state", DEFAULT_AUTO_FLUSH_BUS,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
gobject_class->dispose = gst_pipeline_dispose;
gst_element_class_set_metadata (gstelement_class, "Pipeline object",
"Generic/Bin",
"Complete pipeline object",
"Erik Walthinsen <omega@cse.ogi.edu>, Wim Taymans <wim@fluendo.com>");
gstelement_class->change_state =
GST_DEBUG_FUNCPTR (gst_pipeline_change_state);
gstelement_class->provide_clock =
GST_DEBUG_FUNCPTR (gst_pipeline_provide_clock_func);
gstbin_class->handle_message =
GST_DEBUG_FUNCPTR (gst_pipeline_handle_message);
}
static void
gst_pipeline_init (GstPipeline * pipeline)
{
GstBus *bus;
pipeline->priv = GST_PIPELINE_GET_PRIVATE (pipeline);
/* set default property values */
pipeline->priv->auto_flush_bus = DEFAULT_AUTO_FLUSH_BUS;
pipeline->delay = DEFAULT_DELAY;
/* create and set a default bus */
bus = gst_bus_new ();
#if 0
/* FIXME, disabled for 0.10.5 release as it caused to many regressions */
/* Start our bus in flushing if appropriate */
if (pipeline->priv->auto_flush_bus)
gst_bus_set_flushing (bus, TRUE);
#endif
gst_element_set_bus (GST_ELEMENT_CAST (pipeline), bus);
GST_DEBUG_OBJECT (pipeline, "set bus %" GST_PTR_FORMAT " on pipeline", bus);
gst_object_unref (bus);
}
static void
gst_pipeline_dispose (GObject * object)
{
GstPipeline *pipeline = GST_PIPELINE (object);
GstClock **clock_p = &pipeline->fixed_clock;
GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, pipeline, "dispose");
/* clear and unref any fixed clock */
gst_object_replace ((GstObject **) clock_p, NULL);
G_OBJECT_CLASS (parent_class)->dispose (object);
}
static void
gst_pipeline_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstPipeline *pipeline = GST_PIPELINE (object);
switch (prop_id) {
case PROP_DELAY:
gst_pipeline_set_delay (pipeline, g_value_get_uint64 (value));
break;
case PROP_AUTO_FLUSH_BUS:
gst_pipeline_set_auto_flush_bus (pipeline, g_value_get_boolean (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_pipeline_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstPipeline *pipeline = GST_PIPELINE (object);
switch (prop_id) {
case PROP_DELAY:
g_value_set_uint64 (value, gst_pipeline_get_delay (pipeline));
break;
case PROP_AUTO_FLUSH_BUS:
g_value_set_boolean (value, gst_pipeline_get_auto_flush_bus (pipeline));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
/* set the start_time to 0, this will cause us to select a new base_time and
* make the running_time start from 0 again. */
static void
reset_start_time (GstPipeline * pipeline, GstClockTime start_time)
{
GST_OBJECT_LOCK (pipeline);
if (GST_ELEMENT_START_TIME (pipeline) != GST_CLOCK_TIME_NONE) {
GST_DEBUG_OBJECT (pipeline, "reset start_time to 0");
GST_ELEMENT_START_TIME (pipeline) = start_time;
pipeline->priv->last_start_time = -1;
} else {
GST_DEBUG_OBJECT (pipeline, "application asked to not reset stream_time");
}
GST_OBJECT_UNLOCK (pipeline);
}
/**
* gst_pipeline_new:
* @name: name of new pipeline
*
* Create a new pipeline with the given name.
*
* Returns: (transfer floating): newly created GstPipeline
*
* MT safe.
*/
GstElement *
gst_pipeline_new (const gchar * name)
{
return gst_element_factory_make ("pipeline", name);
}
/* takes a snapshot of the running_time of the pipeline and store this as the
* element start_time. This is the time we will set as the running_time of the
* pipeline when we go to PLAYING next. */
static void
pipeline_update_start_time (GstElement * element)
{
GstPipeline *pipeline = GST_PIPELINE_CAST (element);
GstClock *clock;
GST_OBJECT_LOCK (element);
if ((clock = element->clock)) {
GstClockTime now;
gst_object_ref (clock);
GST_OBJECT_UNLOCK (element);
/* calculate the time when we stopped */
now = gst_clock_get_time (clock);
gst_object_unref (clock);
GST_OBJECT_LOCK (element);
/* store the current running time */
if (GST_ELEMENT_START_TIME (pipeline) != GST_CLOCK_TIME_NONE) {
if (now != GST_CLOCK_TIME_NONE)
GST_ELEMENT_START_TIME (pipeline) = now - element->base_time;
else
GST_WARNING_OBJECT (element,
"Clock %s returned invalid time, can't calculate "
"running_time when going to the PAUSED state",
GST_OBJECT_NAME (clock));
/* we went to PAUSED, when going to PLAYING select clock and new
* base_time */
pipeline->priv->update_clock = TRUE;
}
GST_DEBUG_OBJECT (element,
"start_time=%" GST_TIME_FORMAT ", now=%" GST_TIME_FORMAT
", base_time %" GST_TIME_FORMAT,
GST_TIME_ARGS (GST_ELEMENT_START_TIME (pipeline)),
GST_TIME_ARGS (now), GST_TIME_ARGS (element->base_time));
}
GST_OBJECT_UNLOCK (element);
}
/* MT safe */
static GstStateChangeReturn
gst_pipeline_change_state (GstElement * element, GstStateChange transition)
{
GstStateChangeReturn result = GST_STATE_CHANGE_SUCCESS;
GstPipeline *pipeline = GST_PIPELINE_CAST (element);
GstClock *clock;
switch (transition) {
case GST_STATE_CHANGE_NULL_TO_READY:
GST_OBJECT_LOCK (element);
if (element->bus)
gst_bus_set_flushing (element->bus, FALSE);
GST_OBJECT_UNLOCK (element);
break;
case GST_STATE_CHANGE_READY_TO_PAUSED:
GST_OBJECT_LOCK (element);
pipeline->priv->update_clock = TRUE;
GST_OBJECT_UNLOCK (element);
break;
case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
{
GstClockTime now, start_time, last_start_time, delay;
gboolean update_clock;
GstClock *cur_clock;
GST_DEBUG_OBJECT (element, "selecting clock and base_time");
GST_OBJECT_LOCK (element);
cur_clock = element->clock;
if (cur_clock)
gst_object_ref (cur_clock);
/* get the desired running_time of the first buffer aka the start_time */
start_time = GST_ELEMENT_START_TIME (pipeline);
last_start_time = pipeline->priv->last_start_time;
pipeline->priv->last_start_time = start_time;
/* see if we need to update the clock */
update_clock = pipeline->priv->update_clock;
pipeline->priv->update_clock = FALSE;
delay = pipeline->delay;
GST_OBJECT_UNLOCK (element);
/* running time changed, either with a PAUSED or a flush, we need to check
* if there is a new clock & update the base time */
/* only do this for top-level, however */
if (GST_OBJECT_PARENT (element) == NULL &&
(update_clock || last_start_time != start_time)) {
GST_DEBUG_OBJECT (pipeline, "Need to update start_time");
/* when going to PLAYING, select a clock when needed. If we just got
* flushed, we don't reselect the clock. */
if (update_clock) {
GST_DEBUG_OBJECT (pipeline, "Need to update clock.");
clock = gst_element_provide_clock (element);
} else {
GST_DEBUG_OBJECT (pipeline,
"Don't need to update clock, using old clock.");
clock = gst_object_ref (cur_clock);
}
if (clock) {
now = gst_clock_get_time (clock);
} else {
GST_DEBUG_OBJECT (pipeline, "no clock, using base time of NONE");
now = GST_CLOCK_TIME_NONE;
}
if (clock != cur_clock) {
/* now distribute the clock (which could be NULL). If some
* element refuses the clock, this will return FALSE and
* we effectively fail the state change. */
if (!gst_element_set_clock (element, clock))
goto invalid_clock;
/* if we selected and distributed a new clock, let the app
* know about it */
gst_element_post_message (element,
gst_message_new_new_clock (GST_OBJECT_CAST (element), clock));
}
if (clock)
gst_object_unref (clock);
if (start_time != GST_CLOCK_TIME_NONE && now != GST_CLOCK_TIME_NONE) {
GstClockTime new_base_time = now - start_time + delay;
GST_DEBUG_OBJECT (element,
"start_time=%" GST_TIME_FORMAT ", now=%" GST_TIME_FORMAT
", base_time %" GST_TIME_FORMAT,
GST_TIME_ARGS (start_time), GST_TIME_ARGS (now),
GST_TIME_ARGS (new_base_time));
gst_element_set_base_time (element, new_base_time);
} else {
GST_DEBUG_OBJECT (pipeline,
"NOT adjusting base_time because start_time is NONE");
}
} else {
GST_DEBUG_OBJECT (pipeline,
"NOT adjusting base_time because we selected one before");
}
if (cur_clock)
gst_object_unref (cur_clock);
break;
}
case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
{
/* we take a start_time snapshot before calling the children state changes
* so that they know about when the pipeline PAUSED. */
pipeline_update_start_time (element);
break;
}
case GST_STATE_CHANGE_PAUSED_TO_READY:
case GST_STATE_CHANGE_READY_TO_NULL:
break;
}
result = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
switch (transition) {
case GST_STATE_CHANGE_NULL_TO_READY:
break;
case GST_STATE_CHANGE_READY_TO_PAUSED:
{
/* READY to PAUSED starts running_time from 0 */
reset_start_time (pipeline, 0);
break;
}
case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
break;
case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
{
/* Take a new snapshot of the start_time after calling the state change on
* all children. This will be the running_time of the pipeline when we go
* back to PLAYING */
pipeline_update_start_time (element);
break;
}
case GST_STATE_CHANGE_PAUSED_TO_READY:
break;
case GST_STATE_CHANGE_READY_TO_NULL:
{
GstBus *bus;
gboolean auto_flush;
/* grab some stuff before we release the lock to flush out the bus */
GST_OBJECT_LOCK (element);
if ((bus = element->bus))
gst_object_ref (bus);
auto_flush = pipeline->priv->auto_flush_bus;
GST_OBJECT_UNLOCK (element);
if (bus) {
if (auto_flush) {
gst_bus_set_flushing (bus, TRUE);
} else {
GST_INFO_OBJECT (element, "not flushing bus, auto-flushing disabled");
}
gst_object_unref (bus);
}
break;
}
}
return result;
/* ERRORS */
invalid_clock:
{
/* we generate this error when the selected clock was not
* accepted by some element */
GST_ELEMENT_ERROR (pipeline, CORE, CLOCK,
(_("Selected clock cannot be used in pipeline.")),
("Pipeline cannot operate with selected clock"));
GST_DEBUG_OBJECT (pipeline,
"Pipeline cannot operate with selected clock %p", clock);
if (clock)
gst_object_unref (clock);
return GST_STATE_CHANGE_FAILURE;
}
}
/* intercept the bus messages from our children. We watch for the ASYNC_START
* message with is posted by the elements (sinks) that require a reset of the
* running_time after a flush. ASYNC_START also brings the pipeline back into
* the PAUSED, pending PAUSED state. When the ASYNC_DONE message is received the
* pipeline will redistribute the new base_time and will bring the elements back
* to the desired state of the pipeline. */
static void
gst_pipeline_handle_message (GstBin * bin, GstMessage * message)
{
GstPipeline *pipeline = GST_PIPELINE_CAST (bin);
switch (GST_MESSAGE_TYPE (message)) {
case GST_MESSAGE_RESET_TIME:
{
GstClockTime running_time;
gst_message_parse_reset_time (message, &running_time);
/* reset our running time if we need to distribute a new base_time to the
* children. */
reset_start_time (pipeline, running_time);
break;
}
case GST_MESSAGE_CLOCK_LOST:
{
GstClock *clock;
gst_message_parse_clock_lost (message, &clock);
GST_OBJECT_LOCK (bin);
if (clock == GST_ELEMENT_CAST (bin)->clock) {
GST_DEBUG_OBJECT (bin, "Used clock '%s' got lost",
GST_OBJECT_NAME (clock));
pipeline->priv->update_clock = TRUE;
}
GST_OBJECT_UNLOCK (bin);
}
default:
break;
}
GST_BIN_CLASS (parent_class)->handle_message (bin, message);
}
/**
* gst_pipeline_get_bus:
* @pipeline: a #GstPipeline
*
* Gets the #GstBus of @pipeline. The bus allows applications to receive
* #GstMessage packets.
*
* Returns: (transfer full): a #GstBus, unref after usage.
*
* MT safe.
*/
GstBus *
gst_pipeline_get_bus (GstPipeline * pipeline)
{
return gst_element_get_bus (GST_ELEMENT_CAST (pipeline));
}
static GstClock *
gst_pipeline_provide_clock_func (GstElement * element)
{
GstClock *clock = NULL;
GstPipeline *pipeline = GST_PIPELINE (element);
/* if we have a fixed clock, use that one */
GST_OBJECT_LOCK (pipeline);
if (GST_OBJECT_FLAG_IS_SET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK)) {
clock = pipeline->fixed_clock;
if (clock)
gst_object_ref (clock);
GST_OBJECT_UNLOCK (pipeline);
GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using fixed clock %p (%s)",
clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
} else {
GST_OBJECT_UNLOCK (pipeline);
/* let the parent bin select a clock */
clock =
GST_ELEMENT_CLASS (parent_class)->provide_clock (GST_ELEMENT
(pipeline));
/* no clock, use a system clock */
if (!clock) {
clock = gst_system_clock_obtain ();
GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline obtained system clock: %p (%s)",
clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
} else {
GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline obtained clock: %p (%s)",
clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
}
}
return clock;
}
/**
* gst_pipeline_get_clock:
* @pipeline: a #GstPipeline
*
* Gets the current clock used by @pipeline.
*
* Returns: (transfer full): a #GstClock, unref after usage.
*/
GstClock *
gst_pipeline_get_clock (GstPipeline * pipeline)
{
g_return_val_if_fail (GST_IS_PIPELINE (pipeline), NULL);
return gst_pipeline_provide_clock_func (GST_ELEMENT_CAST (pipeline));
}
/**
* gst_pipeline_use_clock:
* @pipeline: a #GstPipeline
* @clock: (transfer none): the clock to use
*
* Force @pipeline to use the given @clock. The pipeline will
* always use the given clock even if new clock providers are added
* to this pipeline.
*
* If @clock is NULL all clocking will be disabled which will make
* the pipeline run as fast as possible.
*
* MT safe.
*/
void
gst_pipeline_use_clock (GstPipeline * pipeline, GstClock * clock)
{
GstClock **clock_p;
g_return_if_fail (GST_IS_PIPELINE (pipeline));
GST_OBJECT_LOCK (pipeline);
GST_OBJECT_FLAG_SET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK);
clock_p = &pipeline->fixed_clock;
gst_object_replace ((GstObject **) clock_p, (GstObject *) clock);
GST_OBJECT_UNLOCK (pipeline);
GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using fixed clock %p (%s)", clock,
(clock ? GST_OBJECT_NAME (clock) : "nil"));
}
/**
* gst_pipeline_set_clock:
* @pipeline: a #GstPipeline
* @clock: (transfer none): the clock to set
*
* Set the clock for @pipeline. The clock will be distributed
* to all the elements managed by the pipeline.
*
* Returns: TRUE if the clock could be set on the pipeline. FALSE if
* some element did not accept the clock.
*
* MT safe.
*/
gboolean
gst_pipeline_set_clock (GstPipeline * pipeline, GstClock * clock)
{
g_return_val_if_fail (pipeline != NULL, FALSE);
g_return_val_if_fail (GST_IS_PIPELINE (pipeline), FALSE);
return
GST_ELEMENT_CLASS (parent_class)->set_clock (GST_ELEMENT_CAST (pipeline),
clock);
}
/**
* gst_pipeline_auto_clock:
* @pipeline: a #GstPipeline
*
* Let @pipeline select a clock automatically. This is the default
* behaviour.
*
* Use this function if you previous forced a fixed clock with
* gst_pipeline_use_clock() and want to restore the default
* pipeline clock selection algorithm.
*
* MT safe.
*/
void
gst_pipeline_auto_clock (GstPipeline * pipeline)
{
GstClock **clock_p;
g_return_if_fail (pipeline != NULL);
g_return_if_fail (GST_IS_PIPELINE (pipeline));
GST_OBJECT_LOCK (pipeline);
GST_OBJECT_FLAG_UNSET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK);
clock_p = &pipeline->fixed_clock;
gst_object_replace ((GstObject **) clock_p, NULL);
GST_OBJECT_UNLOCK (pipeline);
GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using automatic clock");
}
/**
* gst_pipeline_set_delay:
* @pipeline: a #GstPipeline
* @delay: the delay
*
* Set the expected delay needed for all elements to perform the
* PAUSED to PLAYING state change. @delay will be added to the
* base time of the elements so that they wait an additional @delay
* amount of time before starting to process buffers and cannot be
* #GST_CLOCK_TIME_NONE.
*
* This option is used for tuning purposes and should normally not be
* used.
*
* MT safe.
*
* Since: 0.10.5
*/
void
gst_pipeline_set_delay (GstPipeline * pipeline, GstClockTime delay)
{
g_return_if_fail (GST_IS_PIPELINE (pipeline));
g_return_if_fail (delay != GST_CLOCK_TIME_NONE);
GST_OBJECT_LOCK (pipeline);
pipeline->delay = delay;
GST_OBJECT_UNLOCK (pipeline);
}
/**
* gst_pipeline_get_delay:
* @pipeline: a #GstPipeline
*
* Get the configured delay (see gst_pipeline_set_delay()).
*
* Returns: The configured delay.
*
* MT safe.
*
* Since: 0.10.5
*/
GstClockTime
gst_pipeline_get_delay (GstPipeline * pipeline)
{
GstClockTime res;
g_return_val_if_fail (GST_IS_PIPELINE (pipeline), GST_CLOCK_TIME_NONE);
GST_OBJECT_LOCK (pipeline);
res = pipeline->delay;
GST_OBJECT_UNLOCK (pipeline);
return res;
}
/**
* gst_pipeline_set_auto_flush_bus:
* @pipeline: a #GstPipeline
* @auto_flush: whether or not to automatically flush the bus when
* the pipeline goes from READY to NULL state
*
* Usually, when a pipeline goes from READY to NULL state, it automatically
* flushes all pending messages on the bus, which is done for refcounting
* purposes, to break circular references.
*
* This means that applications that update state using (async) bus messages
* (e.g. do certain things when a pipeline goes from PAUSED to READY) might
* not get to see messages when the pipeline is shut down, because they might
* be flushed before they can be dispatched in the main thread. This behaviour
* can be disabled using this function.
*
* It is important that all messages on the bus are handled when the
* automatic flushing is disabled else memory leaks will be introduced.
*
* MT safe.
*
* Since: 0.10.4
*/
void
gst_pipeline_set_auto_flush_bus (GstPipeline * pipeline, gboolean auto_flush)
{
g_return_if_fail (GST_IS_PIPELINE (pipeline));
GST_OBJECT_LOCK (pipeline);
pipeline->priv->auto_flush_bus = auto_flush;
GST_OBJECT_UNLOCK (pipeline);
}
/**
* gst_pipeline_get_auto_flush_bus:
* @pipeline: a #GstPipeline
*
* Check if @pipeline will automatically flush messages when going to
* the NULL state.
*
* Returns: whether the pipeline will automatically flush its bus when
* going from READY to NULL state or not.
*
* MT safe.
*
* Since: 0.10.4
*/
gboolean
gst_pipeline_get_auto_flush_bus (GstPipeline * pipeline)
{
gboolean res;
g_return_val_if_fail (GST_IS_PIPELINE (pipeline), FALSE);
GST_OBJECT_LOCK (pipeline);
res = pipeline->priv->auto_flush_bus;
GST_OBJECT_UNLOCK (pipeline);
return res;
}