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
32 * application. It will also implement a default behavour for managing
33 * seek events (see gst_element_seek()).
35 * gst_pipeline_new() is used to create a pipeline. when you are done with
36 * the pipeline, use gst_object_unref() to free its resources including all
37 * added #GstElement objects (if not otherwise referenced).
39 * Elements are added and removed from the pipeline using the #GstBin
40 * methods like gst_bin_add() and gst_bin_remove() (see #GstBin).
42 * Before changing the state of the #GstPipeline (see #GstElement) a #GstBus
43 * can be retrieved with gst_pipeline_get_bus(). This bus can then be
44 * used to receive #GstMessage from the elements in the pipeline.
46 * By default, a #GstPipeline will automatically flush the pending #GstBus
47 * messages when going to the NULL state to ensure that no circular
48 * references exist when no messages are read from the #GstBus. This
49 * behaviour can be changed with gst_pipeline_set_auto_flush_bus().
51 * When the #GstPipeline performs the PAUSED to PLAYING state change it will
52 * select a clock for the elements. The clock selection algorithm will by
53 * default select a clock provided by an element that is most upstream
54 * (closest to the source). For live pipelines (ones that return
55 * #GST_STATE_CHANGE_NO_PREROLL from the gst_element_set_state() call) this
56 * will select the clock provided by the live source. For normal pipelines
57 * this will select a clock provided by the sinks (most likely the audio
58 * sink). If no element provides a clock, a default #GstSystemClock is used.
60 * The clock selection can be controlled with the gst_pipeline_use_clock()
61 * method, which will enforce a given clock on the pipeline. With
62 * gst_pipeline_auto_clock() the default clock selection algorithm can be
65 * A #GstPipeline maintains a stream time for the elements. The stream
66 * time is defined as the difference between the current clock time and
67 * the base time. When the pipeline goes to READY or a flushing seek is
68 * performed on it, the stream time is reset to 0. When the pipeline is
69 * set from PLAYING to PAUSED, the current clock time is sampled and used to
70 * configure the base time for the elements when the pipeline is set
71 * to PLAYING again. The effect is that the stream time (as the difference
72 * between the clock time and the base time) will count how much time was spent
73 * in the PLAYING state. This default behaviour can be changed with the
74 * gst_pipeline_set_new_stream_time() method.
76 * When sending a flushing seek event to a GstPipeline (see
77 * gst_element_seek()), it will make sure that the pipeline is properly
78 * PAUSED and resumed as well as set the new stream time to 0 when the
81 * Last reviewed on 2006-03-12 (0.10.5)
84 #include "gst_private.h"
86 #include "gst-i18n-lib.h"
88 #include "gstpipeline.h"
90 #include "gstsystemclock.h"
93 GST_DEBUG_CATEGORY_STATIC (pipeline_debug);
94 #define GST_CAT_DEFAULT pipeline_debug
96 /* Pipeline signals and args */
103 #define DEFAULT_DELAY 0
104 #define DEFAULT_AUTO_FLUSH_BUS TRUE
113 #define GST_PIPELINE_GET_PRIVATE(obj) \
114 (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_PIPELINE, GstPipelinePrivate))
116 struct _GstPipelinePrivate
119 gboolean auto_flush_bus;
121 /* when we need to update stream_time or clock when going back to
123 gboolean update_stream_time;
124 gboolean update_clock;
128 static void gst_pipeline_base_init (gpointer g_class);
130 static void gst_pipeline_dispose (GObject * object);
131 static void gst_pipeline_set_property (GObject * object, guint prop_id,
132 const GValue * value, GParamSpec * pspec);
133 static void gst_pipeline_get_property (GObject * object, guint prop_id,
134 GValue * value, GParamSpec * pspec);
136 static GstClock *gst_pipeline_provide_clock_func (GstElement * element);
137 static GstStateChangeReturn gst_pipeline_change_state (GstElement * element,
138 GstStateChange transition);
140 static void gst_pipeline_handle_message (GstBin * bin, GstMessage * message);
142 /* static guint gst_pipeline_signals[LAST_SIGNAL] = { 0 }; */
144 #define _do_init(type) \
146 GST_DEBUG_CATEGORY_INIT (pipeline_debug, "pipeline", GST_DEBUG_BOLD, \
147 "debugging info for the 'pipeline' container element"); \
150 GST_BOILERPLATE_FULL (GstPipeline, gst_pipeline, GstBin, GST_TYPE_BIN,
154 gst_pipeline_base_init (gpointer g_class)
156 GstElementClass *gstelement_class = GST_ELEMENT_CLASS (g_class);
158 gst_element_class_set_details_simple (gstelement_class, "Pipeline object",
160 "Complete pipeline object",
161 "Erik Walthinsen <omega@cse.ogi.edu>, Wim Taymans <wim@fluendo.com>");
165 gst_pipeline_class_init (GstPipelineClass * klass)
167 GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
168 GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
169 GstBinClass *gstbin_class = GST_BIN_CLASS (klass);
171 parent_class = g_type_class_peek_parent (klass);
173 g_type_class_add_private (klass, sizeof (GstPipelinePrivate));
175 gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_pipeline_set_property);
176 gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_pipeline_get_property);
181 * The expected delay needed for elements to spin up to the
182 * PLAYING state expressed in nanoseconds.
183 * see gst_pipeline_set_delay() for more information on this option.
187 g_object_class_install_property (gobject_class, PROP_DELAY,
188 g_param_spec_uint64 ("delay", "Delay",
189 "Expected delay needed for elements "
190 "to spin up to PLAYING in nanoseconds", 0, G_MAXUINT64, DEFAULT_DELAY,
191 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
194 * GstPipeline:auto-flush-bus:
196 * Whether or not to automatically flush all messages on the
197 * pipeline's bus when going from READY to NULL state. Please see
198 * gst_pipeline_set_auto_flush_bus() for more information on this option.
202 g_object_class_install_property (gobject_class, PROP_AUTO_FLUSH_BUS,
203 g_param_spec_boolean ("auto-flush-bus", "Auto Flush Bus",
204 "Whether to automatically flush the pipeline's bus when going "
205 "from READY into NULL state", DEFAULT_AUTO_FLUSH_BUS,
206 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
208 gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_pipeline_dispose);
210 gstelement_class->change_state =
211 GST_DEBUG_FUNCPTR (gst_pipeline_change_state);
212 gstelement_class->provide_clock =
213 GST_DEBUG_FUNCPTR (gst_pipeline_provide_clock_func);
214 gstbin_class->handle_message =
215 GST_DEBUG_FUNCPTR (gst_pipeline_handle_message);
219 gst_pipeline_init (GstPipeline * pipeline, GstPipelineClass * klass)
223 pipeline->priv = GST_PIPELINE_GET_PRIVATE (pipeline);
225 /* set default property values */
226 pipeline->priv->auto_flush_bus = DEFAULT_AUTO_FLUSH_BUS;
227 pipeline->delay = DEFAULT_DELAY;
229 /* create and set a default bus */
230 bus = gst_bus_new ();
232 /* FIXME, disabled for 0.10.5 release as it caused to many regressions */
233 /* Start our bus in flushing if appropriate */
234 if (pipeline->priv->auto_flush_bus)
235 gst_bus_set_flushing (bus, TRUE);
238 gst_element_set_bus (GST_ELEMENT_CAST (pipeline), bus);
239 GST_DEBUG_OBJECT (pipeline, "set bus %" GST_PTR_FORMAT " on pipeline", bus);
240 gst_object_unref (bus);
244 gst_pipeline_dispose (GObject * object)
246 GstPipeline *pipeline = GST_PIPELINE (object);
247 GstClock **clock_p = &pipeline->fixed_clock;
249 GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, pipeline, "dispose");
251 /* clear and unref any fixed clock */
252 gst_object_replace ((GstObject **) clock_p, NULL);
254 G_OBJECT_CLASS (parent_class)->dispose (object);
258 gst_pipeline_set_property (GObject * object, guint prop_id,
259 const GValue * value, GParamSpec * pspec)
261 GstPipeline *pipeline = GST_PIPELINE (object);
265 gst_pipeline_set_delay (pipeline, g_value_get_uint64 (value));
267 case PROP_AUTO_FLUSH_BUS:
268 gst_pipeline_set_auto_flush_bus (pipeline, g_value_get_boolean (value));
271 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
277 gst_pipeline_get_property (GObject * object, guint prop_id,
278 GValue * value, GParamSpec * pspec)
280 GstPipeline *pipeline = GST_PIPELINE (object);
284 g_value_set_uint64 (value, gst_pipeline_get_delay (pipeline));
286 case PROP_AUTO_FLUSH_BUS:
287 g_value_set_boolean (value, gst_pipeline_get_auto_flush_bus (pipeline));
290 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
295 /* set the stream time to 0 */
297 reset_stream_time (GstPipeline * pipeline)
299 GST_OBJECT_LOCK (pipeline);
300 if (pipeline->stream_time != GST_CLOCK_TIME_NONE) {
301 GST_DEBUG_OBJECT (pipeline, "reset stream_time to 0");
302 pipeline->stream_time = 0;
303 pipeline->priv->update_stream_time = TRUE;
305 GST_DEBUG_OBJECT (pipeline, "application asked to not reset stream_time");
307 GST_OBJECT_UNLOCK (pipeline);
312 * @name: name of new pipeline
314 * Create a new pipeline with the given name.
316 * Returns: newly created GstPipeline
321 gst_pipeline_new (const gchar * name)
323 return gst_element_factory_make ("pipeline", name);
327 static GstStateChangeReturn
328 gst_pipeline_change_state (GstElement * element, GstStateChange transition)
330 GstStateChangeReturn result = GST_STATE_CHANGE_SUCCESS;
331 GstPipeline *pipeline = GST_PIPELINE (element);
334 switch (transition) {
335 case GST_STATE_CHANGE_NULL_TO_READY:
336 GST_OBJECT_LOCK (element);
338 gst_bus_set_flushing (element->bus, FALSE);
339 GST_OBJECT_UNLOCK (element);
341 case GST_STATE_CHANGE_READY_TO_PAUSED:
342 GST_OBJECT_LOCK (element);
343 pipeline->priv->update_clock = TRUE;
344 GST_OBJECT_UNLOCK (element);
346 case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
348 GstClockTime new_base_time;
349 GstClockTime start_time, stream_time, delay;
350 gboolean new_clock, update_stream_time, update_clock;
353 GST_DEBUG_OBJECT (element, "selecting clock and base_time");
355 GST_OBJECT_LOCK (element);
356 cur_clock = element->clock;
358 gst_object_ref (cur_clock);
359 stream_time = pipeline->stream_time;
360 update_stream_time = pipeline->priv->update_stream_time;
361 update_clock = pipeline->priv->update_clock;
362 pipeline->priv->update_stream_time = FALSE;
363 pipeline->priv->update_clock = FALSE;
364 delay = pipeline->delay;
365 GST_OBJECT_UNLOCK (element);
367 /* stream time changed, either with a PAUSED or a flush, we need to check
368 * if there is a new clock & update the base time */
369 if (update_stream_time) {
370 GST_DEBUG_OBJECT (pipeline, "Need to update stream_time");
372 /* when going to PLAYING, select a clock when needed. If we just got
373 * flushed, we don't reselect the clock. */
375 GST_DEBUG_OBJECT (pipeline, "Need to update clock.");
376 clock = gst_element_provide_clock (element);
378 GST_DEBUG_OBJECT (pipeline,
379 "Don't need to update clock, using old clock.");
380 clock = gst_object_ref (cur_clock);
383 new_clock = (clock != cur_clock);
386 start_time = gst_clock_get_time (clock);
388 GST_DEBUG ("no clock, using base time of NONE");
389 start_time = GST_CLOCK_TIME_NONE;
393 /* now distribute the clock (which could be NULL). If some
394 * element refuses the clock, this will return FALSE and
395 * we effectively fail the state change. */
396 if (!gst_element_set_clock (element, clock))
399 /* if we selected and distributed a new clock, let the app
401 gst_element_post_message (element,
402 gst_message_new_new_clock (GST_OBJECT_CAST (element), clock));
406 gst_object_unref (clock);
408 if (stream_time != GST_CLOCK_TIME_NONE
409 && start_time != GST_CLOCK_TIME_NONE) {
410 new_base_time = start_time - stream_time + delay;
411 GST_DEBUG_OBJECT (element,
412 "stream_time=%" GST_TIME_FORMAT ", now=%" GST_TIME_FORMAT
413 ", base_time %" GST_TIME_FORMAT,
414 GST_TIME_ARGS (stream_time), GST_TIME_ARGS (start_time),
415 GST_TIME_ARGS (new_base_time));
417 new_base_time = GST_CLOCK_TIME_NONE;
419 if (new_base_time != GST_CLOCK_TIME_NONE)
420 gst_element_set_base_time (element, new_base_time);
422 GST_DEBUG_OBJECT (pipeline,
423 "NOT adjusting base_time because stream_time is NONE");
425 GST_DEBUG_OBJECT (pipeline,
426 "NOT adjusting base_time because we selected one before");
430 gst_object_unref (cur_clock);
433 case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
435 case GST_STATE_CHANGE_PAUSED_TO_READY:
436 case GST_STATE_CHANGE_READY_TO_NULL:
440 result = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
442 switch (transition) {
443 case GST_STATE_CHANGE_NULL_TO_READY:
445 case GST_STATE_CHANGE_READY_TO_PAUSED:
447 reset_stream_time (pipeline);
450 case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
452 case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
453 GST_OBJECT_LOCK (element);
454 if ((clock = element->clock)) {
457 gst_object_ref (clock);
458 GST_OBJECT_UNLOCK (element);
460 /* calculate the time when we stopped */
461 now = gst_clock_get_time (clock);
462 gst_object_unref (clock);
464 GST_OBJECT_LOCK (element);
465 /* store the current stream time */
466 if (pipeline->stream_time != GST_CLOCK_TIME_NONE) {
467 pipeline->stream_time = now - element->base_time;
468 /* we went to PAUSED, when going to PLAYING select clock and new
470 pipeline->priv->update_stream_time = TRUE;
471 pipeline->priv->update_clock = TRUE;
474 GST_DEBUG_OBJECT (element,
475 "stream_time=%" GST_TIME_FORMAT ", now=%" GST_TIME_FORMAT
476 ", base_time %" GST_TIME_FORMAT,
477 GST_TIME_ARGS (pipeline->stream_time), GST_TIME_ARGS (now),
478 GST_TIME_ARGS (element->base_time));
480 GST_OBJECT_UNLOCK (element);
482 case GST_STATE_CHANGE_PAUSED_TO_READY:
484 case GST_STATE_CHANGE_READY_TO_NULL:
489 /* grab some stuff before we release the lock to flush out the bus */
490 GST_OBJECT_LOCK (element);
491 if ((bus = element->bus))
492 gst_object_ref (bus);
493 auto_flush = pipeline->priv->auto_flush_bus;
494 GST_OBJECT_UNLOCK (element);
498 gst_bus_set_flushing (bus, TRUE);
500 GST_INFO_OBJECT (element, "not flushing bus, auto-flushing disabled");
502 gst_object_unref (bus);
512 /* we generate this error when the selected clock was not
513 * accepted by some element */
514 GST_ELEMENT_ERROR (pipeline, CORE, CLOCK,
515 (_("Selected clock cannot be used in pipeline.")),
516 ("Pipeline cannot operate with selected clock"));
517 GST_DEBUG_OBJECT (pipeline,
518 "Pipeline cannot operate with selected clock %p", clock);
520 gst_object_unref (clock);
521 return GST_STATE_CHANGE_FAILURE;
525 /* intercept the bus messages from our children. We watch for the ASYNC_START
526 * message with is posted by the elements (sinks) that require a reset of the
527 * running_time after a flush. ASYNC_START also brings the pipeline back into
528 * the PAUSED, pending PAUSED state. When the ASYNC_DONE message is received the
529 * pipeline will redistribute the new base_time and will bring the elements back
530 * to the desired state of the pipeline. */
532 gst_pipeline_handle_message (GstBin * bin, GstMessage * message)
534 GstPipeline *pipeline = GST_PIPELINE_CAST (bin);
536 switch (GST_MESSAGE_TYPE (message)) {
537 case GST_MESSAGE_ASYNC_START:
539 gboolean new_base_time;
541 gst_message_parse_async_start (message, &new_base_time);
543 /* reset our stream time if we need to distribute a new base_time to the
546 reset_stream_time (pipeline);
553 GST_BIN_CLASS (parent_class)->handle_message (bin, message);
557 * gst_pipeline_get_bus:
558 * @pipeline: a #GstPipeline
560 * Gets the #GstBus of @pipeline. The bus allows applications to receive #GstMessages.
562 * Returns: a #GstBus, unref after usage.
567 gst_pipeline_get_bus (GstPipeline * pipeline)
569 return gst_element_get_bus (GST_ELEMENT (pipeline));
573 * gst_pipeline_set_new_stream_time:
574 * @pipeline: a #GstPipeline
575 * @time: the new stream time to set
577 * Set the new stream time of @pipeline to @time. The stream time is used to
578 * set the base time on the elements (see gst_element_set_base_time())
579 * in the PAUSED->PLAYING state transition.
581 * Setting @time to #GST_CLOCK_TIME_NONE will disable the pipeline's management
582 * of element base time. The application will then be responsible for
583 * performing base time distribution. This is sometimes useful if you want to
584 * synchronize capture from multiple pipelines, and you can also ensure that the
585 * pipelines have the same clock.
590 gst_pipeline_set_new_stream_time (GstPipeline * pipeline, GstClockTime time)
592 g_return_if_fail (GST_IS_PIPELINE (pipeline));
594 GST_OBJECT_LOCK (pipeline);
595 pipeline->stream_time = time;
596 pipeline->priv->update_stream_time = TRUE;
597 GST_OBJECT_UNLOCK (pipeline);
599 GST_DEBUG_OBJECT (pipeline, "set new stream_time to %" GST_TIME_FORMAT,
600 GST_TIME_ARGS (time));
602 if (time == GST_CLOCK_TIME_NONE)
603 GST_DEBUG_OBJECT (pipeline, "told not to adjust base_time");
607 * gst_pipeline_get_last_stream_time:
608 * @pipeline: a #GstPipeline
610 * Gets the last stream time of @pipeline. If the pipeline is PLAYING,
611 * the returned time is the stream time used to configure the element's
612 * base time in the PAUSED->PLAYING state. If the pipeline is PAUSED, the
613 * returned time is the stream time when the pipeline was paused.
615 * This function returns #GST_CLOCK_TIME_NONE if the pipeline was
616 * configured to not handle the management of the element's base time
617 * (see gst_pipeline_set_new_stream_time()).
619 * Returns: a #GstClockTime.
624 gst_pipeline_get_last_stream_time (GstPipeline * pipeline)
628 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), GST_CLOCK_TIME_NONE);
630 GST_OBJECT_LOCK (pipeline);
631 result = pipeline->stream_time;
632 GST_OBJECT_UNLOCK (pipeline);
638 gst_pipeline_provide_clock_func (GstElement * element)
640 GstClock *clock = NULL;
641 GstPipeline *pipeline = GST_PIPELINE (element);
643 /* if we have a fixed clock, use that one */
644 GST_OBJECT_LOCK (pipeline);
645 if (GST_OBJECT_FLAG_IS_SET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK)) {
646 clock = pipeline->fixed_clock;
648 gst_object_ref (clock);
649 GST_OBJECT_UNLOCK (pipeline);
651 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using fixed clock %p (%s)",
652 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
654 GST_OBJECT_UNLOCK (pipeline);
655 /* let the parent bin select a clock */
657 GST_ELEMENT_CLASS (parent_class)->provide_clock (GST_ELEMENT
659 /* no clock, use a system clock */
661 clock = gst_system_clock_obtain ();
663 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline obtained system clock: %p (%s)",
664 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
666 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline obtained clock: %p (%s)",
667 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
674 * gst_pipeline_get_clock:
675 * @pipeline: a #GstPipeline
677 * Gets the current clock used by @pipeline.
679 * Returns: a #GstClock, unref after usage.
682 gst_pipeline_get_clock (GstPipeline * pipeline)
684 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), NULL);
686 return gst_pipeline_provide_clock_func (GST_ELEMENT (pipeline));
691 * gst_pipeline_use_clock:
692 * @pipeline: a #GstPipeline
693 * @clock: the clock to use
695 * Force @pipeline to use the given @clock. The pipeline will
696 * always use the given clock even if new clock providers are added
699 * If @clock is NULL all clocking will be disabled which will make
700 * the pipeline run as fast as possible.
705 gst_pipeline_use_clock (GstPipeline * pipeline, GstClock * clock)
709 g_return_if_fail (GST_IS_PIPELINE (pipeline));
711 GST_OBJECT_LOCK (pipeline);
712 GST_OBJECT_FLAG_SET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK);
714 clock_p = &pipeline->fixed_clock;
715 gst_object_replace ((GstObject **) clock_p, (GstObject *) clock);
716 GST_OBJECT_UNLOCK (pipeline);
718 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using fixed clock %p (%s)", clock,
719 (clock ? GST_OBJECT_NAME (clock) : "nil"));
723 * gst_pipeline_set_clock:
724 * @pipeline: a #GstPipeline
725 * @clock: the clock to set
727 * Set the clock for @pipeline. The clock will be distributed
728 * to all the elements managed by the pipeline.
730 * Returns: TRUE if the clock could be set on the pipeline. FALSE if
731 * some element did not accept the clock.
736 gst_pipeline_set_clock (GstPipeline * pipeline, GstClock * clock)
738 g_return_val_if_fail (pipeline != NULL, FALSE);
739 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), FALSE);
741 return GST_ELEMENT_CLASS (parent_class)->set_clock (GST_ELEMENT (pipeline),
746 * gst_pipeline_auto_clock:
747 * @pipeline: a #GstPipeline
749 * Let @pipeline select a clock automatically. This is the default
752 * Use this function if you previous forced a fixed clock with
753 * gst_pipeline_use_clock() and want to restore the default
754 * pipeline clock selection algorithm.
759 gst_pipeline_auto_clock (GstPipeline * pipeline)
763 g_return_if_fail (pipeline != NULL);
764 g_return_if_fail (GST_IS_PIPELINE (pipeline));
766 GST_OBJECT_LOCK (pipeline);
767 GST_OBJECT_FLAG_UNSET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK);
769 clock_p = &pipeline->fixed_clock;
770 gst_object_replace ((GstObject **) clock_p, NULL);
771 GST_OBJECT_UNLOCK (pipeline);
773 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using automatic clock");
777 * gst_pipeline_set_delay:
778 * @pipeline: a #GstPipeline
781 * Set the expected delay needed for all elements to perform the
782 * PAUSED to PLAYING state change. @delay will be added to the
783 * base time of the elements so that they wait an additional @delay
784 * amount of time before starting to process buffers and cannot be
785 * #GST_CLOCK_TIME_NONE.
787 * This option is used for tuning purposes and should normally not be
795 gst_pipeline_set_delay (GstPipeline * pipeline, GstClockTime delay)
797 g_return_if_fail (GST_IS_PIPELINE (pipeline));
798 g_return_if_fail (delay != GST_CLOCK_TIME_NONE);
800 GST_OBJECT_LOCK (pipeline);
801 pipeline->delay = delay;
802 GST_OBJECT_UNLOCK (pipeline);
806 * gst_pipeline_get_delay:
807 * @pipeline: a #GstPipeline
809 * Get the configured delay (see gst_pipeline_set_delay()).
811 * Returns: The configured delay.
818 gst_pipeline_get_delay (GstPipeline * pipeline)
822 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), GST_CLOCK_TIME_NONE);
824 GST_OBJECT_LOCK (pipeline);
825 res = pipeline->delay;
826 GST_OBJECT_UNLOCK (pipeline);
832 * gst_pipeline_set_auto_flush_bus:
833 * @pipeline: a #GstPipeline
834 * @auto_flush: whether or not to automatically flush the bus when
835 * the pipeline goes from READY to NULL state
837 * Usually, when a pipeline goes from READY to NULL state, it automatically
838 * flushes all pending messages on the bus, which is done for refcounting
839 * purposes, to break circular references.
841 * This means that applications that update state using (async) bus messages
842 * (e.g. do certain things when a pipeline goes from PAUSED to READY) might
843 * not get to see messages when the pipeline is shut down, because they might
844 * be flushed before they can be dispatched in the main thread. This behaviour
845 * can be disabled using this function.
847 * It is important that all messages on the bus are handled when the
848 * automatic flushing is disabled else memory leaks will be introduced.
855 gst_pipeline_set_auto_flush_bus (GstPipeline * pipeline, gboolean auto_flush)
857 g_return_if_fail (GST_IS_PIPELINE (pipeline));
859 GST_OBJECT_LOCK (pipeline);
860 pipeline->priv->auto_flush_bus = auto_flush;
861 GST_OBJECT_UNLOCK (pipeline);
865 * gst_pipeline_get_auto_flush_bus:
866 * @pipeline: a #GstPipeline
868 * Check if @pipeline will automatically flush messages when going to
871 * Returns: whether the pipeline will automatically flush its bus when
872 * going from READY to NULL state or not.
879 gst_pipeline_get_auto_flush_bus (GstPipeline * pipeline)
883 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), FALSE);
885 GST_OBJECT_LOCK (pipeline);
886 res = pipeline->priv->auto_flush_bus;
887 GST_OBJECT_UNLOCK (pipeline);