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. This default behaviour can be changed with the
72 * gst_pipeline_set_new_stream_time() method.
74 * When sending a flushing seek event to a GstPipeline (see
75 * gst_element_seek()), it will make sure that the pipeline is properly
76 * PAUSED and resumed as well as set the new stream time to 0 when the
79 * Last reviewed on 2006-03-12 (0.10.5)
82 #include "gst_private.h"
84 #include "gst-i18n-lib.h"
86 #include "gstpipeline.h"
88 #include "gstsystemclock.h"
90 GST_DEBUG_CATEGORY_STATIC (pipeline_debug);
91 #define GST_CAT_DEFAULT pipeline_debug
93 static const GstElementDetails gst_pipeline_details =
94 GST_ELEMENT_DETAILS ("Pipeline object",
96 "Complete pipeline object",
97 "Erik Walthinsen <omega@cse.ogi.edu>, Wim Taymans <wim@fluendo.com>");
99 /* Pipeline signals and args */
106 #define DEFAULT_DELAY 0
107 #define DEFAULT_AUTO_FLUSH_BUS TRUE
116 #define GST_PIPELINE_GET_PRIVATE(obj) \
117 (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_PIPELINE, GstPipelinePrivate))
119 struct _GstPipelinePrivate
122 gboolean auto_flush_bus;
124 /* when we need to update stream_time or clock when going back to
126 gboolean update_stream_time;
127 gboolean update_clock;
131 static void gst_pipeline_base_init (gpointer g_class);
132 static void gst_pipeline_class_init (gpointer g_class, gpointer class_data);
133 static void gst_pipeline_init (GTypeInstance * instance, gpointer g_class);
135 static void gst_pipeline_dispose (GObject * object);
136 static void gst_pipeline_set_property (GObject * object, guint prop_id,
137 const GValue * value, GParamSpec * pspec);
138 static void gst_pipeline_get_property (GObject * object, guint prop_id,
139 GValue * value, GParamSpec * pspec);
141 static GstClock *gst_pipeline_provide_clock_func (GstElement * element);
142 static GstStateChangeReturn gst_pipeline_change_state (GstElement * element,
143 GstStateChange transition);
145 static void gst_pipeline_handle_message (GstBin * bin, GstMessage * message);
147 static GstBinClass *parent_class = NULL;
149 /* static guint gst_pipeline_signals[LAST_SIGNAL] = { 0 }; */
152 gst_pipeline_get_type (void)
154 static GType pipeline_type = 0;
156 if (G_UNLIKELY (pipeline_type == 0)) {
157 static const GTypeInfo pipeline_info = {
158 sizeof (GstPipelineClass),
159 gst_pipeline_base_init,
161 (GClassInitFunc) gst_pipeline_class_init,
164 sizeof (GstPipeline),
171 g_type_register_static (GST_TYPE_BIN, "GstPipeline", &pipeline_info, 0);
173 GST_DEBUG_CATEGORY_INIT (pipeline_debug, "pipeline", GST_DEBUG_BOLD,
174 "debugging info for the 'pipeline' container element");
176 return pipeline_type;
180 gst_pipeline_base_init (gpointer g_class)
182 GstElementClass *gstelement_class = GST_ELEMENT_CLASS (g_class);
184 gst_element_class_set_details (gstelement_class, &gst_pipeline_details);
188 gst_pipeline_class_init (gpointer g_class, gpointer class_data)
190 GObjectClass *gobject_class = G_OBJECT_CLASS (g_class);
191 GstElementClass *gstelement_class = GST_ELEMENT_CLASS (g_class);
192 GstBinClass *gstbin_class = GST_BIN_CLASS (g_class);
193 GstPipelineClass *klass = GST_PIPELINE_CLASS (g_class);
195 parent_class = g_type_class_peek_parent (klass);
197 g_type_class_add_private (klass, sizeof (GstPipelinePrivate));
199 gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_pipeline_set_property);
200 gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_pipeline_get_property);
205 * The expected delay needed for elements to spin up to the
206 * PLAYING state expressed in nanoseconds.
207 * see gst_pipeline_set_delay() for more information on this option.
211 g_object_class_install_property (gobject_class, PROP_DELAY,
212 g_param_spec_uint64 ("delay", "Delay",
213 "Expected delay needed for elements "
214 "to spin up to PLAYING in nanoseconds", 0, G_MAXUINT64, DEFAULT_DELAY,
218 * GstPipeline:auto-flush-bus:
220 * Whether or not to automatically flush all messages on the
221 * pipeline's bus when going from READY to NULL state. Please see
222 * gst_pipeline_set_auto_flush_bus() for more information on this option.
226 g_object_class_install_property (gobject_class, PROP_AUTO_FLUSH_BUS,
227 g_param_spec_boolean ("auto-flush-bus", "Auto Flush Bus",
228 "Whether to automatically flush the pipeline's bus when going "
229 "from READY into NULL state", DEFAULT_AUTO_FLUSH_BUS,
232 gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_pipeline_dispose);
234 gstelement_class->change_state =
235 GST_DEBUG_FUNCPTR (gst_pipeline_change_state);
236 gstelement_class->provide_clock =
237 GST_DEBUG_FUNCPTR (gst_pipeline_provide_clock_func);
238 gstbin_class->handle_message =
239 GST_DEBUG_FUNCPTR (gst_pipeline_handle_message);
243 gst_pipeline_init (GTypeInstance * instance, gpointer g_class)
245 GstPipeline *pipeline = GST_PIPELINE (instance);
248 pipeline->priv = GST_PIPELINE_GET_PRIVATE (pipeline);
250 /* set default property values */
251 pipeline->priv->auto_flush_bus = DEFAULT_AUTO_FLUSH_BUS;
252 pipeline->delay = DEFAULT_DELAY;
254 /* create and set a default bus */
255 bus = gst_bus_new ();
257 /* FIXME, disabled for 0.10.5 release as it caused to many regressions */
258 /* Start our bus in flushing if appropriate */
259 if (pipeline->priv->auto_flush_bus)
260 gst_bus_set_flushing (bus, TRUE);
263 gst_element_set_bus (GST_ELEMENT_CAST (pipeline), bus);
264 GST_DEBUG_OBJECT (pipeline, "set bus %" GST_PTR_FORMAT " on pipeline", bus);
265 gst_object_unref (bus);
269 gst_pipeline_dispose (GObject * object)
271 GstPipeline *pipeline = GST_PIPELINE (object);
272 GstClock **clock_p = &pipeline->fixed_clock;
274 GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, pipeline, "dispose");
276 /* clear and unref any fixed clock */
277 gst_object_replace ((GstObject **) clock_p, NULL);
279 G_OBJECT_CLASS (parent_class)->dispose (object);
283 gst_pipeline_set_property (GObject * object, guint prop_id,
284 const GValue * value, GParamSpec * pspec)
286 GstPipeline *pipeline = GST_PIPELINE (object);
290 gst_pipeline_set_delay (pipeline, g_value_get_uint64 (value));
292 case PROP_AUTO_FLUSH_BUS:
293 gst_pipeline_set_auto_flush_bus (pipeline, g_value_get_boolean (value));
296 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
302 gst_pipeline_get_property (GObject * object, guint prop_id,
303 GValue * value, GParamSpec * pspec)
305 GstPipeline *pipeline = GST_PIPELINE (object);
309 g_value_set_uint64 (value, gst_pipeline_get_delay (pipeline));
311 case PROP_AUTO_FLUSH_BUS:
312 g_value_set_boolean (value, gst_pipeline_get_auto_flush_bus (pipeline));
315 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
320 /* set the stream time to 0 */
322 reset_stream_time (GstPipeline * pipeline)
324 GST_OBJECT_LOCK (pipeline);
325 if (pipeline->stream_time != GST_CLOCK_TIME_NONE) {
326 GST_DEBUG_OBJECT (pipeline, "reset stream_time to 0");
327 pipeline->stream_time = 0;
328 pipeline->priv->update_stream_time = TRUE;
330 GST_DEBUG_OBJECT (pipeline, "application asked to not reset stream_time");
332 GST_OBJECT_UNLOCK (pipeline);
337 * @name: name of new pipeline
339 * Create a new pipeline with the given name.
341 * Returns: newly created GstPipeline
346 gst_pipeline_new (const gchar * name)
348 return gst_element_factory_make ("pipeline", name);
352 static GstStateChangeReturn
353 gst_pipeline_change_state (GstElement * element, GstStateChange transition)
355 GstStateChangeReturn result = GST_STATE_CHANGE_SUCCESS;
356 GstPipeline *pipeline = GST_PIPELINE (element);
359 switch (transition) {
360 case GST_STATE_CHANGE_NULL_TO_READY:
361 GST_OBJECT_LOCK (element);
363 gst_bus_set_flushing (element->bus, FALSE);
364 GST_OBJECT_UNLOCK (element);
366 case GST_STATE_CHANGE_READY_TO_PAUSED:
367 GST_OBJECT_LOCK (element);
368 pipeline->priv->update_clock = TRUE;
369 GST_OBJECT_UNLOCK (element);
371 case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
373 GstClockTime new_base_time;
374 GstClockTime start_time, stream_time, delay;
375 gboolean new_clock, update_stream_time, update_clock;
378 GST_DEBUG_OBJECT (element, "selecting clock and base_time");
380 GST_OBJECT_LOCK (element);
381 cur_clock = element->clock;
383 gst_object_ref (cur_clock);
384 stream_time = pipeline->stream_time;
385 update_stream_time = pipeline->priv->update_stream_time;
386 update_clock = pipeline->priv->update_clock;
387 pipeline->priv->update_stream_time = FALSE;
388 pipeline->priv->update_clock = FALSE;
389 delay = pipeline->delay;
390 GST_OBJECT_UNLOCK (element);
392 /* stream time changed, either with a PAUSED or a flush, we need to check
393 * if there is a new clock & update the base time */
394 if (update_stream_time) {
395 GST_DEBUG_OBJECT (pipeline, "Need to update stream_time");
397 /* when going to PLAYING, select a clock when needed. If we just got
398 * flushed, we don't reselect the clock. */
400 GST_DEBUG_OBJECT (pipeline, "Need to update clock.");
401 clock = gst_element_provide_clock (element);
403 GST_DEBUG_OBJECT (pipeline,
404 "Don't need to update clock, using old clock.");
405 clock = gst_object_ref (cur_clock);
408 new_clock = (clock != cur_clock);
411 start_time = gst_clock_get_time (clock);
413 GST_DEBUG ("no clock, using base time of NONE");
414 start_time = GST_CLOCK_TIME_NONE;
415 new_base_time = GST_CLOCK_TIME_NONE;
419 /* now distribute the clock (which could be NULL). If some
420 * element refuses the clock, this will return FALSE and
421 * we effectively fail the state change. */
422 if (!gst_element_set_clock (element, clock))
425 /* if we selected and distributed a new clock, let the app
427 gst_element_post_message (element,
428 gst_message_new_new_clock (GST_OBJECT_CAST (element), clock));
432 gst_object_unref (clock);
434 if (stream_time != GST_CLOCK_TIME_NONE
435 && start_time != GST_CLOCK_TIME_NONE) {
436 new_base_time = start_time - stream_time + delay;
437 GST_DEBUG_OBJECT (element,
438 "stream_time=%" GST_TIME_FORMAT ", now=%" GST_TIME_FORMAT
439 ", base_time %" GST_TIME_FORMAT,
440 GST_TIME_ARGS (stream_time), GST_TIME_ARGS (start_time),
441 GST_TIME_ARGS (new_base_time));
443 new_base_time = GST_CLOCK_TIME_NONE;
445 if (new_base_time != GST_CLOCK_TIME_NONE)
446 gst_element_set_base_time (element, new_base_time);
448 GST_DEBUG_OBJECT (pipeline,
449 "NOT adjusting base_time because stream_time is NONE");
451 GST_DEBUG_OBJECT (pipeline,
452 "NOT adjusting base_time because we selected one before");
456 gst_object_unref (cur_clock);
459 case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
461 case GST_STATE_CHANGE_PAUSED_TO_READY:
462 case GST_STATE_CHANGE_READY_TO_NULL:
466 result = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
468 switch (transition) {
469 case GST_STATE_CHANGE_NULL_TO_READY:
471 case GST_STATE_CHANGE_READY_TO_PAUSED:
473 reset_stream_time (pipeline);
476 case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
478 case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
479 GST_OBJECT_LOCK (element);
480 if ((clock = element->clock)) {
483 gst_object_ref (clock);
484 GST_OBJECT_UNLOCK (element);
486 /* calculate the time when we stopped */
487 now = gst_clock_get_time (clock);
488 gst_object_unref (clock);
490 GST_OBJECT_LOCK (element);
491 /* store the current stream time */
492 if (pipeline->stream_time != GST_CLOCK_TIME_NONE) {
493 pipeline->stream_time = now - element->base_time;
494 /* we went to PAUSED, when going to PLAYING select clock and new
496 pipeline->priv->update_stream_time = TRUE;
497 pipeline->priv->update_clock = TRUE;
500 GST_DEBUG_OBJECT (element,
501 "stream_time=%" GST_TIME_FORMAT ", now=%" GST_TIME_FORMAT
502 ", base_time %" GST_TIME_FORMAT,
503 GST_TIME_ARGS (pipeline->stream_time), GST_TIME_ARGS (now),
504 GST_TIME_ARGS (element->base_time));
506 GST_OBJECT_UNLOCK (element);
508 case GST_STATE_CHANGE_PAUSED_TO_READY:
510 case GST_STATE_CHANGE_READY_TO_NULL:
511 GST_OBJECT_LOCK (element);
513 if (pipeline->priv->auto_flush_bus) {
514 gst_bus_set_flushing (element->bus, TRUE);
516 GST_INFO_OBJECT (element, "not flushing bus, auto-flushing disabled");
519 GST_OBJECT_UNLOCK (element);
527 /* we generate this error when the selected clock was not
528 * accepted by some element */
529 GST_ELEMENT_ERROR (pipeline, CORE, CLOCK,
530 (_("Selected clock cannot be used in pipeline.")),
531 ("Pipeline cannot operate with selected clock"));
532 GST_DEBUG_OBJECT (pipeline,
533 "Pipeline cannot operate with selected clock %p", clock);
535 gst_object_unref (clock);
536 return GST_STATE_CHANGE_FAILURE;
541 gst_pipeline_handle_message (GstBin * bin, GstMessage * message)
543 GstPipeline *pipeline = GST_PIPELINE_CAST (bin);
545 switch (GST_MESSAGE_TYPE (message)) {
546 case GST_MESSAGE_ASYNC_START:
548 gboolean new_base_time;
550 gst_message_parse_async_start (message, &new_base_time);
552 /* reset our stream time if we need to distribute a new base_time to the
555 reset_stream_time (pipeline);
562 GST_BIN_CLASS (parent_class)->handle_message (bin, message);
566 * gst_pipeline_get_bus:
567 * @pipeline: a #GstPipeline
569 * Gets the #GstBus of @pipeline.
571 * Returns: a #GstBus, unref after usage.
576 gst_pipeline_get_bus (GstPipeline * pipeline)
578 return gst_element_get_bus (GST_ELEMENT (pipeline));
582 * gst_pipeline_set_new_stream_time:
583 * @pipeline: a #GstPipeline
584 * @time: the new stream time to set
586 * Set the new stream time of @pipeline to @time. The stream time is used to
587 * set the base time on the elements (see gst_element_set_base_time())
588 * in the PAUSED->PLAYING state transition.
590 * Setting @time to #GST_CLOCK_TIME_NONE will disable the pipeline's management
591 * of element base time. The application will then be responsible for
592 * performing base time distribution. This is sometimes useful if you want to
593 * synchronize capture from multiple pipelines, and you can also ensure that the
594 * pipelines have the same clock.
599 gst_pipeline_set_new_stream_time (GstPipeline * pipeline, GstClockTime time)
601 g_return_if_fail (GST_IS_PIPELINE (pipeline));
603 GST_OBJECT_LOCK (pipeline);
604 pipeline->stream_time = time;
605 pipeline->priv->update_stream_time = TRUE;
606 GST_OBJECT_UNLOCK (pipeline);
608 GST_DEBUG_OBJECT (pipeline, "set new stream_time to %" GST_TIME_FORMAT,
609 GST_TIME_ARGS (time));
611 if (time == GST_CLOCK_TIME_NONE)
612 GST_DEBUG_OBJECT (pipeline, "told not to adjust base_time");
616 * gst_pipeline_get_last_stream_time:
617 * @pipeline: a #GstPipeline
619 * Gets the last stream time of @pipeline. If the pipeline is PLAYING,
620 * the returned time is the stream time used to configure the element's
621 * base time in the PAUSED->PLAYING state. If the pipeline is PAUSED, the
622 * returned time is the stream time when the pipeline was paused.
624 * This function returns #GST_CLOCK_TIME_NONE if the pipeline was
625 * configured to not handle the management of the element's base time
626 * (see gst_pipeline_set_new_stream_time()).
628 * Returns: a #GstClockTime.
633 gst_pipeline_get_last_stream_time (GstPipeline * pipeline)
637 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), GST_CLOCK_TIME_NONE);
639 GST_OBJECT_LOCK (pipeline);
640 result = pipeline->stream_time;
641 GST_OBJECT_UNLOCK (pipeline);
647 gst_pipeline_provide_clock_func (GstElement * element)
649 GstClock *clock = NULL;
650 GstPipeline *pipeline = GST_PIPELINE (element);
652 /* if we have a fixed clock, use that one */
653 GST_OBJECT_LOCK (pipeline);
654 if (GST_OBJECT_FLAG_IS_SET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK)) {
655 clock = pipeline->fixed_clock;
657 gst_object_ref (clock);
658 GST_OBJECT_UNLOCK (pipeline);
660 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using fixed clock %p (%s)",
661 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
663 GST_OBJECT_UNLOCK (pipeline);
664 /* let the parent bin select a clock */
666 GST_ELEMENT_CLASS (parent_class)->
667 provide_clock (GST_ELEMENT (pipeline));
668 /* no clock, use a system clock */
670 clock = gst_system_clock_obtain ();
672 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline obtained system clock: %p (%s)",
673 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
675 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline obtained clock: %p (%s)",
676 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
683 * gst_pipeline_get_clock:
684 * @pipeline: a #GstPipeline
686 * Gets the current clock used by @pipeline.
688 * Returns: a #GstClock, unref after usage.
691 gst_pipeline_get_clock (GstPipeline * pipeline)
693 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), NULL);
695 return gst_pipeline_provide_clock_func (GST_ELEMENT (pipeline));
700 * gst_pipeline_use_clock:
701 * @pipeline: a #GstPipeline
702 * @clock: the clock to use
704 * Force @pipeline to use the given @clock. The pipeline will
705 * always use the given clock even if new clock providers are added
708 * If @clock is NULL all clocking will be disabled which will make
709 * the pipeline run as fast as possible.
714 gst_pipeline_use_clock (GstPipeline * pipeline, GstClock * clock)
718 g_return_if_fail (GST_IS_PIPELINE (pipeline));
720 GST_OBJECT_LOCK (pipeline);
721 GST_OBJECT_FLAG_SET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK);
723 clock_p = &pipeline->fixed_clock;
724 gst_object_replace ((GstObject **) clock_p, (GstObject *) clock);
725 GST_OBJECT_UNLOCK (pipeline);
727 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using fixed clock %p (%s)", clock,
728 (clock ? GST_OBJECT_NAME (clock) : "nil"));
732 * gst_pipeline_set_clock:
733 * @pipeline: a #GstPipeline
734 * @clock: the clock to set
736 * Set the clock for @pipeline. The clock will be distributed
737 * to all the elements managed by the pipeline.
739 * Returns: TRUE if the clock could be set on the pipeline. FALSE if
740 * some element did not accept the clock.
745 gst_pipeline_set_clock (GstPipeline * pipeline, GstClock * clock)
747 g_return_val_if_fail (pipeline != NULL, FALSE);
748 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), FALSE);
750 return GST_ELEMENT_CLASS (parent_class)->set_clock (GST_ELEMENT (pipeline),
755 * gst_pipeline_auto_clock:
756 * @pipeline: a #GstPipeline
758 * Let @pipeline select a clock automatically. This is the default
761 * Use this function if you previous forced a fixed clock with
762 * gst_pipeline_use_clock() and want to restore the default
763 * pipeline clock selection algorithm.
768 gst_pipeline_auto_clock (GstPipeline * pipeline)
772 g_return_if_fail (pipeline != NULL);
773 g_return_if_fail (GST_IS_PIPELINE (pipeline));
775 GST_OBJECT_LOCK (pipeline);
776 GST_OBJECT_FLAG_UNSET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK);
778 clock_p = &pipeline->fixed_clock;
779 gst_object_replace ((GstObject **) clock_p, NULL);
780 GST_OBJECT_UNLOCK (pipeline);
782 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using automatic clock");
786 * gst_pipeline_set_delay:
787 * @pipeline: a #GstPipeline
790 * Set the expected delay needed for all elements to perform the
791 * PAUSED to PLAYING state change. @delay will be added to the
792 * base time of the elements so that they wait an additional @delay
793 * amount of time before starting to process buffers and cannot be
794 * #GST_CLOCK_TIME_NONE.
796 * This option is used for tuning purposes and should normally not be
804 gst_pipeline_set_delay (GstPipeline * pipeline, GstClockTime delay)
806 g_return_if_fail (GST_IS_PIPELINE (pipeline));
807 g_return_if_fail (delay != GST_CLOCK_TIME_NONE);
809 GST_OBJECT_LOCK (pipeline);
810 pipeline->delay = delay;
811 GST_OBJECT_UNLOCK (pipeline);
815 * gst_pipeline_get_delay:
816 * @pipeline: a #GstPipeline
818 * Get the configured delay (see gst_pipeline_set_delay()).
820 * Returns: The configured delay.
827 gst_pipeline_get_delay (GstPipeline * pipeline)
831 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), GST_CLOCK_TIME_NONE);
833 GST_OBJECT_LOCK (pipeline);
834 res = pipeline->delay;
835 GST_OBJECT_UNLOCK (pipeline);
841 * gst_pipeline_set_auto_flush_bus:
842 * @pipeline: a #GstPipeline
843 * @auto_flush: whether or not to automatically flush the bus when
844 * the pipeline goes from READY to NULL state
846 * Usually, when a pipeline goes from READY to NULL state, it automatically
847 * flushes all pending messages on the bus, which is done for refcounting
848 * purposes, to break circular references.
850 * This means that applications that update state using (async) bus messages
851 * (e.g. do certain things when a pipeline goes from PAUSED to READY) might
852 * not get to see messages when the pipeline is shut down, because they might
853 * be flushed before they can be dispatched in the main thread. This behaviour
854 * can be disabled using this function.
856 * It is important that all messages on the bus are handled when the
857 * automatic flushing is disabled else memory leaks will be introduced.
864 gst_pipeline_set_auto_flush_bus (GstPipeline * pipeline, gboolean auto_flush)
866 g_return_if_fail (GST_IS_PIPELINE (pipeline));
868 GST_OBJECT_LOCK (pipeline);
869 pipeline->priv->auto_flush_bus = auto_flush;
870 GST_OBJECT_UNLOCK (pipeline);
874 * gst_pipeline_get_auto_flush_bus:
875 * @pipeline: a #GstPipeline
877 * Check if @pipeline will automatically flush messages when going to
880 * Returns: whether the pipeline will automatically flush its bus when
881 * going from READY to NULL state or not.
888 gst_pipeline_get_auto_flush_bus (GstPipeline * pipeline)
892 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), FALSE);
894 GST_OBJECT_LOCK (pipeline);
895 res = pipeline->priv->auto_flush_bus;
896 GST_OBJECT_UNLOCK (pipeline);