2 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
3 * 2004,2005 Wim Taymans <wim@fluendo.com>
5 * gstpipeline.c: Overall pipeline management element
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Library General Public License for more details.
17 * You should have received a copy of the GNU Library General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
25 * @short_description: Top-level bin with clocking and bus management
27 * @see_also: #GstElement, #GstBin, #GstClock, #GstBus
29 * A #GstPipeline is a special #GstBin used as the toplevel container for
30 * the filter graph. The #GstPipeline will manage the selection and
31 * distribution of a global #GstClock as well as provide a #GstBus to the
34 * gst_pipeline_new() is used to create a pipeline. when you are done with
35 * the pipeline, use gst_object_unref() to free its resources including all
36 * added #GstElement objects (if not otherwise referenced).
38 * Elements are added and removed from the pipeline using the #GstBin
39 * methods like gst_bin_add() and gst_bin_remove() (see #GstBin).
41 * Before changing the state of the #GstPipeline (see #GstElement) a #GstBus
42 * can be retrieved with gst_pipeline_get_bus(). This bus can then be
43 * used to receive #GstMessage from the elements in the pipeline.
45 * By default, a #GstPipeline will automatically flush the pending #GstBus
46 * messages when going to the NULL state to ensure that no circular
47 * references exist when no messages are read from the #GstBus. This
48 * behaviour can be changed with gst_pipeline_set_auto_flush_bus().
50 * When the #GstPipeline performs the PAUSED to PLAYING state change it will
51 * select a clock for the elements. The clock selection algorithm will by
52 * default select a clock provided by an element that is most upstream
53 * (closest to the source). For live pipelines (ones that return
54 * #GST_STATE_CHANGE_NO_PREROLL from the gst_element_set_state() call) this
55 * will select the clock provided by the live source. For normal pipelines
56 * this will select a clock provided by the sinks (most likely the audio
57 * sink). If no element provides a clock, a default #GstSystemClock is used.
59 * The clock selection can be controlled with the gst_pipeline_use_clock()
60 * method, which will enforce a given clock on the pipeline. With
61 * gst_pipeline_auto_clock() the default clock selection algorithm can be
64 * A #GstPipeline maintains a running time for the elements. The running
65 * time is defined as the difference between the current clock time and
66 * the base time. When the pipeline goes to READY or a flushing seek is
67 * performed on it, the running time is reset to 0. When the pipeline is
68 * set from PLAYING to PAUSED, the current clock time is sampled and used to
69 * configure the base time for the elements when the pipeline is set
70 * to PLAYING again. The effect is that the running time (as the difference
71 * between the clock time and the base time) will count how much time was spent
72 * in the PLAYING state. This default behaviour can be changed with the
73 * gst_element_set_start_time() method.
75 * Last reviewed on 2012-03-29 (0.11.3)
78 #include "gst_private.h"
80 #include "gst-i18n-lib.h"
82 #include "gstpipeline.h"
84 #include "gstsystemclock.h"
87 GST_DEBUG_CATEGORY_STATIC (pipeline_debug);
88 #define GST_CAT_DEFAULT pipeline_debug
90 /* Pipeline signals and args */
97 #define DEFAULT_DELAY 0
98 #define DEFAULT_AUTO_FLUSH_BUS TRUE
107 #define GST_PIPELINE_GET_PRIVATE(obj) \
108 (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_PIPELINE, GstPipelinePrivate))
110 struct _GstPipelinePrivate
113 gboolean auto_flush_bus;
115 /* when we need to update stream_time or clock when going back to
117 GstClockTime last_start_time;
118 gboolean update_clock;
122 static void gst_pipeline_dispose (GObject * object);
123 static void gst_pipeline_set_property (GObject * object, guint prop_id,
124 const GValue * value, GParamSpec * pspec);
125 static void gst_pipeline_get_property (GObject * object, guint prop_id,
126 GValue * value, GParamSpec * pspec);
128 static GstClock *gst_pipeline_provide_clock_func (GstElement * element);
129 static GstStateChangeReturn gst_pipeline_change_state (GstElement * element,
130 GstStateChange transition);
132 static void gst_pipeline_handle_message (GstBin * bin, GstMessage * message);
134 /* static guint gst_pipeline_signals[LAST_SIGNAL] = { 0 }; */
138 GST_DEBUG_CATEGORY_INIT (pipeline_debug, "pipeline", GST_DEBUG_BOLD, \
139 "debugging info for the 'pipeline' container element"); \
142 #define gst_pipeline_parent_class parent_class
143 G_DEFINE_TYPE_WITH_CODE (GstPipeline, gst_pipeline, GST_TYPE_BIN, _do_init);
146 gst_pipeline_class_init (GstPipelineClass * klass)
148 GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
149 GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
150 GstBinClass *gstbin_class = GST_BIN_CLASS (klass);
152 g_type_class_add_private (klass, sizeof (GstPipelinePrivate));
154 gobject_class->set_property = gst_pipeline_set_property;
155 gobject_class->get_property = gst_pipeline_get_property;
160 * The expected delay needed for elements to spin up to the
161 * PLAYING state expressed in nanoseconds.
162 * see gst_pipeline_set_delay() for more information on this option.
166 g_object_class_install_property (gobject_class, PROP_DELAY,
167 g_param_spec_uint64 ("delay", "Delay",
168 "Expected delay needed for elements "
169 "to spin up to PLAYING in nanoseconds", 0, G_MAXUINT64, DEFAULT_DELAY,
170 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
173 * GstPipeline:auto-flush-bus:
175 * Whether or not to automatically flush all messages on the
176 * pipeline's bus when going from READY to NULL state. Please see
177 * gst_pipeline_set_auto_flush_bus() for more information on this option.
181 g_object_class_install_property (gobject_class, PROP_AUTO_FLUSH_BUS,
182 g_param_spec_boolean ("auto-flush-bus", "Auto Flush Bus",
183 "Whether to automatically flush the pipeline's bus when going "
184 "from READY into NULL state", DEFAULT_AUTO_FLUSH_BUS,
185 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
187 gobject_class->dispose = gst_pipeline_dispose;
189 gst_element_class_set_metadata (gstelement_class, "Pipeline object",
191 "Complete pipeline object",
192 "Erik Walthinsen <omega@cse.ogi.edu>, Wim Taymans <wim@fluendo.com>");
194 gstelement_class->change_state =
195 GST_DEBUG_FUNCPTR (gst_pipeline_change_state);
196 gstelement_class->provide_clock =
197 GST_DEBUG_FUNCPTR (gst_pipeline_provide_clock_func);
198 gstbin_class->handle_message =
199 GST_DEBUG_FUNCPTR (gst_pipeline_handle_message);
203 gst_pipeline_init (GstPipeline * pipeline)
207 pipeline->priv = GST_PIPELINE_GET_PRIVATE (pipeline);
209 /* set default property values */
210 pipeline->priv->auto_flush_bus = DEFAULT_AUTO_FLUSH_BUS;
211 pipeline->delay = DEFAULT_DELAY;
213 /* create and set a default bus */
214 bus = gst_bus_new ();
216 /* FIXME, disabled for 0.10.5 release as it caused to many regressions */
217 /* Start our bus in flushing if appropriate */
218 if (pipeline->priv->auto_flush_bus)
219 gst_bus_set_flushing (bus, TRUE);
222 gst_element_set_bus (GST_ELEMENT_CAST (pipeline), bus);
223 GST_DEBUG_OBJECT (pipeline, "set bus %" GST_PTR_FORMAT " on pipeline", bus);
224 gst_object_unref (bus);
228 gst_pipeline_dispose (GObject * object)
230 GstPipeline *pipeline = GST_PIPELINE (object);
231 GstClock **clock_p = &pipeline->fixed_clock;
233 GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, pipeline, "dispose");
235 /* clear and unref any fixed clock */
236 gst_object_replace ((GstObject **) clock_p, NULL);
238 G_OBJECT_CLASS (parent_class)->dispose (object);
242 gst_pipeline_set_property (GObject * object, guint prop_id,
243 const GValue * value, GParamSpec * pspec)
245 GstPipeline *pipeline = GST_PIPELINE (object);
249 gst_pipeline_set_delay (pipeline, g_value_get_uint64 (value));
251 case PROP_AUTO_FLUSH_BUS:
252 gst_pipeline_set_auto_flush_bus (pipeline, g_value_get_boolean (value));
255 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
261 gst_pipeline_get_property (GObject * object, guint prop_id,
262 GValue * value, GParamSpec * pspec)
264 GstPipeline *pipeline = GST_PIPELINE (object);
268 g_value_set_uint64 (value, gst_pipeline_get_delay (pipeline));
270 case PROP_AUTO_FLUSH_BUS:
271 g_value_set_boolean (value, gst_pipeline_get_auto_flush_bus (pipeline));
274 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
279 /* set the start_time to 0, this will cause us to select a new base_time and
280 * make the running_time start from 0 again. */
282 reset_start_time (GstPipeline * pipeline, GstClockTime start_time)
284 GST_OBJECT_LOCK (pipeline);
285 if (GST_ELEMENT_START_TIME (pipeline) != GST_CLOCK_TIME_NONE) {
286 GST_DEBUG_OBJECT (pipeline, "reset start_time to 0");
287 GST_ELEMENT_START_TIME (pipeline) = start_time;
288 pipeline->priv->last_start_time = -1;
290 GST_DEBUG_OBJECT (pipeline, "application asked to not reset stream_time");
292 GST_OBJECT_UNLOCK (pipeline);
297 * @name: name of new pipeline
299 * Create a new pipeline with the given name.
301 * Returns: (transfer floating): newly created GstPipeline
306 gst_pipeline_new (const gchar * name)
308 return gst_element_factory_make ("pipeline", name);
311 /* takes a snapshot of the running_time of the pipeline and store this as the
312 * element start_time. This is the time we will set as the running_time of the
313 * pipeline when we go to PLAYING next. */
315 pipeline_update_start_time (GstElement * element)
317 GstPipeline *pipeline = GST_PIPELINE_CAST (element);
320 GST_OBJECT_LOCK (element);
321 if ((clock = element->clock)) {
324 gst_object_ref (clock);
325 GST_OBJECT_UNLOCK (element);
327 /* calculate the time when we stopped */
328 now = gst_clock_get_time (clock);
329 gst_object_unref (clock);
331 GST_OBJECT_LOCK (element);
332 /* store the current running time */
333 if (GST_ELEMENT_START_TIME (pipeline) != GST_CLOCK_TIME_NONE) {
334 if (now != GST_CLOCK_TIME_NONE)
335 GST_ELEMENT_START_TIME (pipeline) = now - element->base_time;
337 GST_WARNING_OBJECT (element,
338 "Clock %s returned invalid time, can't calculate "
339 "running_time when going to the PAUSED state",
340 GST_OBJECT_NAME (clock));
342 /* we went to PAUSED, when going to PLAYING select clock and new
344 pipeline->priv->update_clock = TRUE;
346 GST_DEBUG_OBJECT (element,
347 "start_time=%" GST_TIME_FORMAT ", now=%" GST_TIME_FORMAT
348 ", base_time %" GST_TIME_FORMAT,
349 GST_TIME_ARGS (GST_ELEMENT_START_TIME (pipeline)),
350 GST_TIME_ARGS (now), GST_TIME_ARGS (element->base_time));
352 GST_OBJECT_UNLOCK (element);
356 static GstStateChangeReturn
357 gst_pipeline_change_state (GstElement * element, GstStateChange transition)
359 GstStateChangeReturn result = GST_STATE_CHANGE_SUCCESS;
360 GstPipeline *pipeline = GST_PIPELINE_CAST (element);
363 switch (transition) {
364 case GST_STATE_CHANGE_NULL_TO_READY:
365 GST_OBJECT_LOCK (element);
367 gst_bus_set_flushing (element->bus, FALSE);
368 GST_OBJECT_UNLOCK (element);
370 case GST_STATE_CHANGE_READY_TO_PAUSED:
371 GST_OBJECT_LOCK (element);
372 pipeline->priv->update_clock = TRUE;
373 GST_OBJECT_UNLOCK (element);
375 case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
377 GstClockTime now, start_time, last_start_time, delay;
378 gboolean update_clock;
381 GST_DEBUG_OBJECT (element, "selecting clock and base_time");
383 GST_OBJECT_LOCK (element);
384 cur_clock = element->clock;
386 gst_object_ref (cur_clock);
387 /* get the desired running_time of the first buffer aka the start_time */
388 start_time = GST_ELEMENT_START_TIME (pipeline);
389 last_start_time = pipeline->priv->last_start_time;
390 pipeline->priv->last_start_time = start_time;
391 /* see if we need to update the clock */
392 update_clock = pipeline->priv->update_clock;
393 pipeline->priv->update_clock = FALSE;
394 delay = pipeline->delay;
395 GST_OBJECT_UNLOCK (element);
397 /* running time changed, either with a PAUSED or a flush, we need to check
398 * if there is a new clock & update the base time */
399 /* only do this for top-level, however */
400 if (GST_OBJECT_PARENT (element) == NULL &&
401 (update_clock || last_start_time != start_time)) {
402 GST_DEBUG_OBJECT (pipeline, "Need to update start_time");
404 /* when going to PLAYING, select a clock when needed. If we just got
405 * flushed, we don't reselect the clock. */
407 GST_DEBUG_OBJECT (pipeline, "Need to update clock.");
408 clock = gst_element_provide_clock (element);
410 GST_DEBUG_OBJECT (pipeline,
411 "Don't need to update clock, using old clock.");
412 clock = gst_object_ref (cur_clock);
416 now = gst_clock_get_time (clock);
418 GST_DEBUG_OBJECT (pipeline, "no clock, using base time of NONE");
419 now = GST_CLOCK_TIME_NONE;
422 if (clock != cur_clock) {
423 /* now distribute the clock (which could be NULL). If some
424 * element refuses the clock, this will return FALSE and
425 * we effectively fail the state change. */
426 if (!gst_element_set_clock (element, clock))
429 /* if we selected and distributed a new clock, let the app
431 gst_element_post_message (element,
432 gst_message_new_new_clock (GST_OBJECT_CAST (element), clock));
436 gst_object_unref (clock);
438 if (start_time != GST_CLOCK_TIME_NONE && now != GST_CLOCK_TIME_NONE) {
439 GstClockTime new_base_time = now - start_time + delay;
440 GST_DEBUG_OBJECT (element,
441 "start_time=%" GST_TIME_FORMAT ", now=%" GST_TIME_FORMAT
442 ", base_time %" GST_TIME_FORMAT,
443 GST_TIME_ARGS (start_time), GST_TIME_ARGS (now),
444 GST_TIME_ARGS (new_base_time));
446 gst_element_set_base_time (element, new_base_time);
448 GST_DEBUG_OBJECT (pipeline,
449 "NOT adjusting base_time because start_time is NONE");
452 GST_DEBUG_OBJECT (pipeline,
453 "NOT adjusting base_time because we selected one before");
457 gst_object_unref (cur_clock);
460 case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
462 /* we take a start_time snapshot before calling the children state changes
463 * so that they know about when the pipeline PAUSED. */
464 pipeline_update_start_time (element);
467 case GST_STATE_CHANGE_PAUSED_TO_READY:
468 case GST_STATE_CHANGE_READY_TO_NULL:
472 result = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
474 switch (transition) {
475 case GST_STATE_CHANGE_NULL_TO_READY:
477 case GST_STATE_CHANGE_READY_TO_PAUSED:
479 /* READY to PAUSED starts running_time from 0 */
480 reset_start_time (pipeline, 0);
483 case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
485 case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
487 /* Take a new snapshot of the start_time after calling the state change on
488 * all children. This will be the running_time of the pipeline when we go
490 pipeline_update_start_time (element);
493 case GST_STATE_CHANGE_PAUSED_TO_READY:
495 case GST_STATE_CHANGE_READY_TO_NULL:
500 /* grab some stuff before we release the lock to flush out the bus */
501 GST_OBJECT_LOCK (element);
502 if ((bus = element->bus))
503 gst_object_ref (bus);
504 auto_flush = pipeline->priv->auto_flush_bus;
505 GST_OBJECT_UNLOCK (element);
509 gst_bus_set_flushing (bus, TRUE);
511 GST_INFO_OBJECT (element, "not flushing bus, auto-flushing disabled");
513 gst_object_unref (bus);
523 /* we generate this error when the selected clock was not
524 * accepted by some element */
525 GST_ELEMENT_ERROR (pipeline, CORE, CLOCK,
526 (_("Selected clock cannot be used in pipeline.")),
527 ("Pipeline cannot operate with selected clock"));
528 GST_DEBUG_OBJECT (pipeline,
529 "Pipeline cannot operate with selected clock %p", clock);
531 gst_object_unref (clock);
532 return GST_STATE_CHANGE_FAILURE;
536 /* intercept the bus messages from our children. We watch for the ASYNC_START
537 * message with is posted by the elements (sinks) that require a reset of the
538 * running_time after a flush. ASYNC_START also brings the pipeline back into
539 * the PAUSED, pending PAUSED state. When the ASYNC_DONE message is received the
540 * pipeline will redistribute the new base_time and will bring the elements back
541 * to the desired state of the pipeline. */
543 gst_pipeline_handle_message (GstBin * bin, GstMessage * message)
545 GstPipeline *pipeline = GST_PIPELINE_CAST (bin);
547 switch (GST_MESSAGE_TYPE (message)) {
548 case GST_MESSAGE_RESET_TIME:
550 GstClockTime running_time;
552 gst_message_parse_reset_time (message, &running_time);
554 /* reset our running time if we need to distribute a new base_time to the
556 reset_start_time (pipeline, running_time);
559 case GST_MESSAGE_CLOCK_LOST:
563 gst_message_parse_clock_lost (message, &clock);
565 GST_OBJECT_LOCK (bin);
566 if (clock == GST_ELEMENT_CAST (bin)->clock) {
567 GST_DEBUG_OBJECT (bin, "Used clock '%s' got lost",
568 GST_OBJECT_NAME (clock));
569 pipeline->priv->update_clock = TRUE;
571 GST_OBJECT_UNLOCK (bin);
576 GST_BIN_CLASS (parent_class)->handle_message (bin, message);
580 * gst_pipeline_get_bus:
581 * @pipeline: a #GstPipeline
583 * Gets the #GstBus of @pipeline. The bus allows applications to receive
584 * #GstMessage packets.
586 * Returns: (transfer full): a #GstBus, unref after usage.
591 gst_pipeline_get_bus (GstPipeline * pipeline)
593 return gst_element_get_bus (GST_ELEMENT_CAST (pipeline));
597 gst_pipeline_provide_clock_func (GstElement * element)
599 GstClock *clock = NULL;
600 GstPipeline *pipeline = GST_PIPELINE (element);
602 /* if we have a fixed clock, use that one */
603 GST_OBJECT_LOCK (pipeline);
604 if (GST_OBJECT_FLAG_IS_SET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK)) {
605 clock = pipeline->fixed_clock;
607 gst_object_ref (clock);
608 GST_OBJECT_UNLOCK (pipeline);
610 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using fixed clock %p (%s)",
611 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
613 GST_OBJECT_UNLOCK (pipeline);
614 /* let the parent bin select a clock */
616 GST_ELEMENT_CLASS (parent_class)->provide_clock (GST_ELEMENT
618 /* no clock, use a system clock */
620 clock = gst_system_clock_obtain ();
622 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline obtained system clock: %p (%s)",
623 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
625 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline obtained clock: %p (%s)",
626 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
633 * gst_pipeline_get_clock:
634 * @pipeline: a #GstPipeline
636 * Gets the current clock used by @pipeline.
638 * Returns: (transfer full): a #GstClock, unref after usage.
641 gst_pipeline_get_clock (GstPipeline * pipeline)
643 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), NULL);
645 return gst_pipeline_provide_clock_func (GST_ELEMENT_CAST (pipeline));
650 * gst_pipeline_use_clock:
651 * @pipeline: a #GstPipeline
652 * @clock: (transfer none): the clock to use
654 * Force @pipeline to use the given @clock. The pipeline will
655 * always use the given clock even if new clock providers are added
658 * If @clock is NULL all clocking will be disabled which will make
659 * the pipeline run as fast as possible.
664 gst_pipeline_use_clock (GstPipeline * pipeline, GstClock * clock)
668 g_return_if_fail (GST_IS_PIPELINE (pipeline));
670 GST_OBJECT_LOCK (pipeline);
671 GST_OBJECT_FLAG_SET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK);
673 clock_p = &pipeline->fixed_clock;
674 gst_object_replace ((GstObject **) clock_p, (GstObject *) clock);
675 GST_OBJECT_UNLOCK (pipeline);
677 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using fixed clock %p (%s)", clock,
678 (clock ? GST_OBJECT_NAME (clock) : "nil"));
682 * gst_pipeline_set_clock:
683 * @pipeline: a #GstPipeline
684 * @clock: (transfer none): the clock to set
686 * Set the clock for @pipeline. The clock will be distributed
687 * to all the elements managed by the pipeline.
689 * Returns: TRUE if the clock could be set on the pipeline. FALSE if
690 * some element did not accept the clock.
695 gst_pipeline_set_clock (GstPipeline * pipeline, GstClock * clock)
697 g_return_val_if_fail (pipeline != NULL, FALSE);
698 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), FALSE);
701 GST_ELEMENT_CLASS (parent_class)->set_clock (GST_ELEMENT_CAST (pipeline),
706 * gst_pipeline_auto_clock:
707 * @pipeline: a #GstPipeline
709 * Let @pipeline select a clock automatically. This is the default
712 * Use this function if you previous forced a fixed clock with
713 * gst_pipeline_use_clock() and want to restore the default
714 * pipeline clock selection algorithm.
719 gst_pipeline_auto_clock (GstPipeline * pipeline)
723 g_return_if_fail (pipeline != NULL);
724 g_return_if_fail (GST_IS_PIPELINE (pipeline));
726 GST_OBJECT_LOCK (pipeline);
727 GST_OBJECT_FLAG_UNSET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK);
729 clock_p = &pipeline->fixed_clock;
730 gst_object_replace ((GstObject **) clock_p, NULL);
731 GST_OBJECT_UNLOCK (pipeline);
733 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using automatic clock");
737 * gst_pipeline_set_delay:
738 * @pipeline: a #GstPipeline
741 * Set the expected delay needed for all elements to perform the
742 * PAUSED to PLAYING state change. @delay will be added to the
743 * base time of the elements so that they wait an additional @delay
744 * amount of time before starting to process buffers and cannot be
745 * #GST_CLOCK_TIME_NONE.
747 * This option is used for tuning purposes and should normally not be
755 gst_pipeline_set_delay (GstPipeline * pipeline, GstClockTime delay)
757 g_return_if_fail (GST_IS_PIPELINE (pipeline));
758 g_return_if_fail (delay != GST_CLOCK_TIME_NONE);
760 GST_OBJECT_LOCK (pipeline);
761 pipeline->delay = delay;
762 GST_OBJECT_UNLOCK (pipeline);
766 * gst_pipeline_get_delay:
767 * @pipeline: a #GstPipeline
769 * Get the configured delay (see gst_pipeline_set_delay()).
771 * Returns: The configured delay.
778 gst_pipeline_get_delay (GstPipeline * pipeline)
782 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), GST_CLOCK_TIME_NONE);
784 GST_OBJECT_LOCK (pipeline);
785 res = pipeline->delay;
786 GST_OBJECT_UNLOCK (pipeline);
792 * gst_pipeline_set_auto_flush_bus:
793 * @pipeline: a #GstPipeline
794 * @auto_flush: whether or not to automatically flush the bus when
795 * the pipeline goes from READY to NULL state
797 * Usually, when a pipeline goes from READY to NULL state, it automatically
798 * flushes all pending messages on the bus, which is done for refcounting
799 * purposes, to break circular references.
801 * This means that applications that update state using (async) bus messages
802 * (e.g. do certain things when a pipeline goes from PAUSED to READY) might
803 * not get to see messages when the pipeline is shut down, because they might
804 * be flushed before they can be dispatched in the main thread. This behaviour
805 * can be disabled using this function.
807 * It is important that all messages on the bus are handled when the
808 * automatic flushing is disabled else memory leaks will be introduced.
815 gst_pipeline_set_auto_flush_bus (GstPipeline * pipeline, gboolean auto_flush)
817 g_return_if_fail (GST_IS_PIPELINE (pipeline));
819 GST_OBJECT_LOCK (pipeline);
820 pipeline->priv->auto_flush_bus = auto_flush;
821 GST_OBJECT_UNLOCK (pipeline);
825 * gst_pipeline_get_auto_flush_bus:
826 * @pipeline: a #GstPipeline
828 * Check if @pipeline will automatically flush messages when going to
831 * Returns: whether the pipeline will automatically flush its bus when
832 * going from READY to NULL state or not.
839 gst_pipeline_get_auto_flush_bus (GstPipeline * pipeline)
843 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), FALSE);
845 GST_OBJECT_LOCK (pipeline);
846 res = pipeline->priv->auto_flush_bus;
847 GST_OBJECT_UNLOCK (pipeline);