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 running time for the elements. The running
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 running 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 running 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_element_set_start_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 running time to 0 when the
81 * Last reviewed on 2009-05-29 (0.10.24)
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 GstClockTime last_start_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 start_time to 0, this will cause us to select a new base_time and
296 * make the running_time start from 0 again. */
298 reset_start_time (GstPipeline * pipeline)
300 GST_OBJECT_LOCK (pipeline);
301 if (GST_ELEMENT_START_TIME (pipeline) != GST_CLOCK_TIME_NONE) {
302 GST_DEBUG_OBJECT (pipeline, "reset start_time to 0");
303 GST_ELEMENT_START_TIME (pipeline) = 0;
304 pipeline->priv->last_start_time = -1;
306 GST_DEBUG_OBJECT (pipeline, "application asked to not reset stream_time");
308 GST_OBJECT_UNLOCK (pipeline);
313 * @name: name of new pipeline
315 * Create a new pipeline with the given name.
317 * Returns: newly created GstPipeline
322 gst_pipeline_new (const gchar * name)
324 return gst_element_factory_make ("pipeline", name);
328 static GstStateChangeReturn
329 gst_pipeline_change_state (GstElement * element, GstStateChange transition)
331 GstStateChangeReturn result = GST_STATE_CHANGE_SUCCESS;
332 GstPipeline *pipeline = GST_PIPELINE (element);
335 switch (transition) {
336 case GST_STATE_CHANGE_NULL_TO_READY:
337 GST_OBJECT_LOCK (element);
339 gst_bus_set_flushing (element->bus, FALSE);
340 GST_OBJECT_UNLOCK (element);
342 case GST_STATE_CHANGE_READY_TO_PAUSED:
343 GST_OBJECT_LOCK (element);
344 pipeline->priv->update_clock = TRUE;
345 GST_OBJECT_UNLOCK (element);
347 case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
349 GstClockTime now, start_time, last_start_time, delay;
350 gboolean 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 /* get the desired running_time of the first buffer aka the start_time */
360 start_time = GST_ELEMENT_START_TIME (pipeline);
361 last_start_time = pipeline->priv->last_start_time;
362 pipeline->priv->last_start_time = start_time;
363 /* see if we need to update the clock */
364 update_clock = pipeline->priv->update_clock;
365 pipeline->priv->update_clock = FALSE;
366 delay = pipeline->delay;
367 GST_OBJECT_UNLOCK (element);
369 /* running time changed, either with a PAUSED or a flush, we need to check
370 * if there is a new clock & update the base time */
371 if (last_start_time != start_time) {
372 GST_DEBUG_OBJECT (pipeline, "Need to update start_time");
374 /* when going to PLAYING, select a clock when needed. If we just got
375 * flushed, we don't reselect the clock. */
377 GST_DEBUG_OBJECT (pipeline, "Need to update clock.");
378 clock = gst_element_provide_clock (element);
380 GST_DEBUG_OBJECT (pipeline,
381 "Don't need to update clock, using old clock.");
382 clock = gst_object_ref (cur_clock);
386 now = gst_clock_get_time (clock);
388 GST_DEBUG ("no clock, using base time of NONE");
389 now = GST_CLOCK_TIME_NONE;
392 if (clock != cur_clock) {
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 (start_time != GST_CLOCK_TIME_NONE && now != GST_CLOCK_TIME_NONE) {
409 GstClockTime new_base_time = now - start_time + delay;
410 GST_DEBUG_OBJECT (element,
411 "start_time=%" GST_TIME_FORMAT ", now=%" GST_TIME_FORMAT
412 ", base_time %" GST_TIME_FORMAT,
413 GST_TIME_ARGS (start_time), GST_TIME_ARGS (now),
414 GST_TIME_ARGS (new_base_time));
416 gst_element_set_base_time (element, new_base_time);
418 GST_DEBUG_OBJECT (pipeline,
419 "NOT adjusting base_time because start_time is NONE");
422 GST_DEBUG_OBJECT (pipeline,
423 "NOT adjusting base_time because we selected one before");
427 gst_object_unref (cur_clock);
430 case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
431 GST_OBJECT_LOCK (element);
432 if ((clock = element->clock)) {
435 gst_object_ref (clock);
436 GST_OBJECT_UNLOCK (element);
438 /* calculate the time when we stopped */
439 now = gst_clock_get_time (clock);
440 gst_object_unref (clock);
442 GST_OBJECT_LOCK (element);
443 /* store the current running time */
444 if (GST_ELEMENT_START_TIME (pipeline) != GST_CLOCK_TIME_NONE) {
445 GST_ELEMENT_START_TIME (pipeline) = now - element->base_time;
446 /* we went to PAUSED, when going to PLAYING select clock and new
448 pipeline->priv->update_clock = TRUE;
450 GST_DEBUG_OBJECT (element,
451 "start_time=%" GST_TIME_FORMAT ", now=%" GST_TIME_FORMAT
452 ", base_time %" GST_TIME_FORMAT,
453 GST_TIME_ARGS (GST_ELEMENT_START_TIME (pipeline)),
454 GST_TIME_ARGS (now), GST_TIME_ARGS (element->base_time));
456 GST_OBJECT_UNLOCK (element);
459 case GST_STATE_CHANGE_PAUSED_TO_READY:
460 case GST_STATE_CHANGE_READY_TO_NULL:
464 result = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
466 switch (transition) {
467 case GST_STATE_CHANGE_NULL_TO_READY:
469 case GST_STATE_CHANGE_READY_TO_PAUSED:
471 reset_start_time (pipeline);
474 case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
476 case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
478 case GST_STATE_CHANGE_PAUSED_TO_READY:
480 case GST_STATE_CHANGE_READY_TO_NULL:
485 /* grab some stuff before we release the lock to flush out the bus */
486 GST_OBJECT_LOCK (element);
487 if ((bus = element->bus))
488 gst_object_ref (bus);
489 auto_flush = pipeline->priv->auto_flush_bus;
490 GST_OBJECT_UNLOCK (element);
494 gst_bus_set_flushing (bus, TRUE);
496 GST_INFO_OBJECT (element, "not flushing bus, auto-flushing disabled");
498 gst_object_unref (bus);
508 /* we generate this error when the selected clock was not
509 * accepted by some element */
510 GST_ELEMENT_ERROR (pipeline, CORE, CLOCK,
511 (_("Selected clock cannot be used in pipeline.")),
512 ("Pipeline cannot operate with selected clock"));
513 GST_DEBUG_OBJECT (pipeline,
514 "Pipeline cannot operate with selected clock %p", clock);
516 gst_object_unref (clock);
517 return GST_STATE_CHANGE_FAILURE;
521 /* intercept the bus messages from our children. We watch for the ASYNC_START
522 * message with is posted by the elements (sinks) that require a reset of the
523 * running_time after a flush. ASYNC_START also brings the pipeline back into
524 * the PAUSED, pending PAUSED state. When the ASYNC_DONE message is received the
525 * pipeline will redistribute the new base_time and will bring the elements back
526 * to the desired state of the pipeline. */
528 gst_pipeline_handle_message (GstBin * bin, GstMessage * message)
530 GstPipeline *pipeline = GST_PIPELINE_CAST (bin);
532 switch (GST_MESSAGE_TYPE (message)) {
533 case GST_MESSAGE_ASYNC_START:
535 gboolean new_base_time;
537 gst_message_parse_async_start (message, &new_base_time);
539 /* reset our running time if we need to distribute a new base_time to the
542 reset_start_time (pipeline);
549 GST_BIN_CLASS (parent_class)->handle_message (bin, message);
553 * gst_pipeline_get_bus:
554 * @pipeline: a #GstPipeline
556 * Gets the #GstBus of @pipeline. The bus allows applications to receive #GstMessages.
558 * Returns: a #GstBus, unref after usage.
563 gst_pipeline_get_bus (GstPipeline * pipeline)
565 return gst_element_get_bus (GST_ELEMENT (pipeline));
569 * gst_pipeline_set_new_stream_time:
570 * @pipeline: a #GstPipeline
571 * @time: the new running time to set
573 * Set the new start time of @pipeline to @time. The start time is used to
574 * set the base time on the elements (see gst_element_set_base_time())
575 * in the PAUSED->PLAYING state transition.
577 * Setting @time to #GST_CLOCK_TIME_NONE will disable the pipeline's management
578 * of element base time. The application will then be responsible for
579 * performing base time distribution. This is sometimes useful if you want to
580 * synchronize capture from multiple pipelines, and you can also ensure that the
581 * pipelines have the same clock.
585 * Deprecated: This function has the wrong name and is equivalent to
586 * gst_element_set_start_time().
588 #ifndef GST_REMOVE_DEPRECATED
590 gst_pipeline_set_new_stream_time (GstPipeline * pipeline, GstClockTime time)
592 g_return_if_fail (GST_IS_PIPELINE (pipeline));
594 gst_element_set_start_time (GST_ELEMENT_CAST (pipeline), time);
596 if (time == GST_CLOCK_TIME_NONE)
597 GST_DEBUG_OBJECT (pipeline, "told not to adjust base_time");
599 #endif /* GST_REMOVE_DEPRECATED */
602 * gst_pipeline_get_last_stream_time:
603 * @pipeline: a #GstPipeline
605 * Gets the last running time of @pipeline. If the pipeline is PLAYING,
606 * the returned time is the running time used to configure the element's
607 * base time in the PAUSED->PLAYING state. If the pipeline is PAUSED, the
608 * returned time is the running time when the pipeline was paused.
610 * This function returns #GST_CLOCK_TIME_NONE if the pipeline was
611 * configured to not handle the management of the element's base time
612 * (see gst_pipeline_set_new_stream_time()).
616 * Returns: a #GstClockTime.
618 * Deprecated: This function has the wrong name and is equivalent to
619 * gst_element_get_start_time().
621 #ifndef GST_REMOVE_DEPRECATED
623 gst_pipeline_get_last_stream_time (GstPipeline * pipeline)
627 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), GST_CLOCK_TIME_NONE);
629 result = gst_element_get_start_time (GST_ELEMENT_CAST (pipeline));
633 #endif /* GST_REMOVE_DEPRECATED */
636 gst_pipeline_provide_clock_func (GstElement * element)
638 GstClock *clock = NULL;
639 GstPipeline *pipeline = GST_PIPELINE (element);
641 /* if we have a fixed clock, use that one */
642 GST_OBJECT_LOCK (pipeline);
643 if (GST_OBJECT_FLAG_IS_SET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK)) {
644 clock = pipeline->fixed_clock;
646 gst_object_ref (clock);
647 GST_OBJECT_UNLOCK (pipeline);
649 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using fixed clock %p (%s)",
650 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
652 GST_OBJECT_UNLOCK (pipeline);
653 /* let the parent bin select a clock */
655 GST_ELEMENT_CLASS (parent_class)->provide_clock (GST_ELEMENT
657 /* no clock, use a system clock */
659 clock = gst_system_clock_obtain ();
661 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline obtained system clock: %p (%s)",
662 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
664 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline obtained clock: %p (%s)",
665 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
672 * gst_pipeline_get_clock:
673 * @pipeline: a #GstPipeline
675 * Gets the current clock used by @pipeline.
677 * Returns: a #GstClock, unref after usage.
680 gst_pipeline_get_clock (GstPipeline * pipeline)
682 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), NULL);
684 return gst_pipeline_provide_clock_func (GST_ELEMENT (pipeline));
689 * gst_pipeline_use_clock:
690 * @pipeline: a #GstPipeline
691 * @clock: the clock to use
693 * Force @pipeline to use the given @clock. The pipeline will
694 * always use the given clock even if new clock providers are added
697 * If @clock is NULL all clocking will be disabled which will make
698 * the pipeline run as fast as possible.
703 gst_pipeline_use_clock (GstPipeline * pipeline, GstClock * clock)
707 g_return_if_fail (GST_IS_PIPELINE (pipeline));
709 GST_OBJECT_LOCK (pipeline);
710 GST_OBJECT_FLAG_SET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK);
712 clock_p = &pipeline->fixed_clock;
713 gst_object_replace ((GstObject **) clock_p, (GstObject *) clock);
714 GST_OBJECT_UNLOCK (pipeline);
716 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using fixed clock %p (%s)", clock,
717 (clock ? GST_OBJECT_NAME (clock) : "nil"));
721 * gst_pipeline_set_clock:
722 * @pipeline: a #GstPipeline
723 * @clock: the clock to set
725 * Set the clock for @pipeline. The clock will be distributed
726 * to all the elements managed by the pipeline.
728 * Returns: TRUE if the clock could be set on the pipeline. FALSE if
729 * some element did not accept the clock.
734 gst_pipeline_set_clock (GstPipeline * pipeline, GstClock * clock)
736 g_return_val_if_fail (pipeline != NULL, FALSE);
737 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), FALSE);
739 return GST_ELEMENT_CLASS (parent_class)->set_clock (GST_ELEMENT (pipeline),
744 * gst_pipeline_auto_clock:
745 * @pipeline: a #GstPipeline
747 * Let @pipeline select a clock automatically. This is the default
750 * Use this function if you previous forced a fixed clock with
751 * gst_pipeline_use_clock() and want to restore the default
752 * pipeline clock selection algorithm.
757 gst_pipeline_auto_clock (GstPipeline * pipeline)
761 g_return_if_fail (pipeline != NULL);
762 g_return_if_fail (GST_IS_PIPELINE (pipeline));
764 GST_OBJECT_LOCK (pipeline);
765 GST_OBJECT_FLAG_UNSET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK);
767 clock_p = &pipeline->fixed_clock;
768 gst_object_replace ((GstObject **) clock_p, NULL);
769 GST_OBJECT_UNLOCK (pipeline);
771 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using automatic clock");
775 * gst_pipeline_set_delay:
776 * @pipeline: a #GstPipeline
779 * Set the expected delay needed for all elements to perform the
780 * PAUSED to PLAYING state change. @delay will be added to the
781 * base time of the elements so that they wait an additional @delay
782 * amount of time before starting to process buffers and cannot be
783 * #GST_CLOCK_TIME_NONE.
785 * This option is used for tuning purposes and should normally not be
793 gst_pipeline_set_delay (GstPipeline * pipeline, GstClockTime delay)
795 g_return_if_fail (GST_IS_PIPELINE (pipeline));
796 g_return_if_fail (delay != GST_CLOCK_TIME_NONE);
798 GST_OBJECT_LOCK (pipeline);
799 pipeline->delay = delay;
800 GST_OBJECT_UNLOCK (pipeline);
804 * gst_pipeline_get_delay:
805 * @pipeline: a #GstPipeline
807 * Get the configured delay (see gst_pipeline_set_delay()).
809 * Returns: The configured delay.
816 gst_pipeline_get_delay (GstPipeline * pipeline)
820 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), GST_CLOCK_TIME_NONE);
822 GST_OBJECT_LOCK (pipeline);
823 res = pipeline->delay;
824 GST_OBJECT_UNLOCK (pipeline);
830 * gst_pipeline_set_auto_flush_bus:
831 * @pipeline: a #GstPipeline
832 * @auto_flush: whether or not to automatically flush the bus when
833 * the pipeline goes from READY to NULL state
835 * Usually, when a pipeline goes from READY to NULL state, it automatically
836 * flushes all pending messages on the bus, which is done for refcounting
837 * purposes, to break circular references.
839 * This means that applications that update state using (async) bus messages
840 * (e.g. do certain things when a pipeline goes from PAUSED to READY) might
841 * not get to see messages when the pipeline is shut down, because they might
842 * be flushed before they can be dispatched in the main thread. This behaviour
843 * can be disabled using this function.
845 * It is important that all messages on the bus are handled when the
846 * automatic flushing is disabled else memory leaks will be introduced.
853 gst_pipeline_set_auto_flush_bus (GstPipeline * pipeline, gboolean auto_flush)
855 g_return_if_fail (GST_IS_PIPELINE (pipeline));
857 GST_OBJECT_LOCK (pipeline);
858 pipeline->priv->auto_flush_bus = auto_flush;
859 GST_OBJECT_UNLOCK (pipeline);
863 * gst_pipeline_get_auto_flush_bus:
864 * @pipeline: a #GstPipeline
866 * Check if @pipeline will automatically flush messages when going to
869 * Returns: whether the pipeline will automatically flush its bus when
870 * going from READY to NULL state or not.
877 gst_pipeline_get_auto_flush_bus (GstPipeline * pipeline)
881 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), FALSE);
883 GST_OBJECT_LOCK (pipeline);
884 res = pipeline->priv->auto_flush_bus;
885 GST_OBJECT_UNLOCK (pipeline);