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"
92 GST_DEBUG_CATEGORY_STATIC (pipeline_debug);
93 #define GST_CAT_DEFAULT pipeline_debug
95 /* Pipeline signals and args */
102 #define DEFAULT_DELAY 0
103 #define DEFAULT_AUTO_FLUSH_BUS TRUE
112 #define GST_PIPELINE_GET_PRIVATE(obj) \
113 (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_PIPELINE, GstPipelinePrivate))
115 struct _GstPipelinePrivate
118 gboolean auto_flush_bus;
120 /* when we need to update stream_time or clock when going back to
122 gboolean update_stream_time;
123 gboolean update_clock;
127 static void gst_pipeline_base_init (gpointer g_class);
128 static void gst_pipeline_class_init (gpointer g_class, gpointer class_data);
129 static void gst_pipeline_init (GTypeInstance * instance, gpointer g_class);
131 static void gst_pipeline_dispose (GObject * object);
132 static void gst_pipeline_set_property (GObject * object, guint prop_id,
133 const GValue * value, GParamSpec * pspec);
134 static void gst_pipeline_get_property (GObject * object, guint prop_id,
135 GValue * value, GParamSpec * pspec);
137 static GstClock *gst_pipeline_provide_clock_func (GstElement * element);
138 static GstStateChangeReturn gst_pipeline_change_state (GstElement * element,
139 GstStateChange transition);
141 static void gst_pipeline_handle_message (GstBin * bin, GstMessage * message);
143 static GstBinClass *parent_class = NULL;
145 /* static guint gst_pipeline_signals[LAST_SIGNAL] = { 0 }; */
148 gst_pipeline_get_type (void)
150 static GType pipeline_type = 0;
152 if (G_UNLIKELY (pipeline_type == 0)) {
153 static const GTypeInfo pipeline_info = {
154 sizeof (GstPipelineClass),
155 gst_pipeline_base_init,
157 (GClassInitFunc) gst_pipeline_class_init,
160 sizeof (GstPipeline),
167 g_type_register_static (GST_TYPE_BIN, "GstPipeline", &pipeline_info, 0);
169 GST_DEBUG_CATEGORY_INIT (pipeline_debug, "pipeline", GST_DEBUG_BOLD,
170 "debugging info for the 'pipeline' container element");
172 return pipeline_type;
176 gst_pipeline_base_init (gpointer g_class)
178 GstElementClass *gstelement_class = GST_ELEMENT_CLASS (g_class);
180 gst_element_class_set_details_simple (gstelement_class, "Pipeline object",
182 "Complete pipeline object",
183 "Erik Walthinsen <omega@cse.ogi.edu>, Wim Taymans <wim@fluendo.com>");
187 gst_pipeline_class_init (gpointer g_class, gpointer class_data)
189 GObjectClass *gobject_class = G_OBJECT_CLASS (g_class);
190 GstElementClass *gstelement_class = GST_ELEMENT_CLASS (g_class);
191 GstBinClass *gstbin_class = GST_BIN_CLASS (g_class);
192 GstPipelineClass *klass = GST_PIPELINE_CLASS (g_class);
194 parent_class = g_type_class_peek_parent (klass);
196 g_type_class_add_private (klass, sizeof (GstPipelinePrivate));
198 gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_pipeline_set_property);
199 gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_pipeline_get_property);
204 * The expected delay needed for elements to spin up to the
205 * PLAYING state expressed in nanoseconds.
206 * see gst_pipeline_set_delay() for more information on this option.
210 g_object_class_install_property (gobject_class, PROP_DELAY,
211 g_param_spec_uint64 ("delay", "Delay",
212 "Expected delay needed for elements "
213 "to spin up to PLAYING in nanoseconds", 0, G_MAXUINT64, DEFAULT_DELAY,
214 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
217 * GstPipeline:auto-flush-bus:
219 * Whether or not to automatically flush all messages on the
220 * pipeline's bus when going from READY to NULL state. Please see
221 * gst_pipeline_set_auto_flush_bus() for more information on this option.
225 g_object_class_install_property (gobject_class, PROP_AUTO_FLUSH_BUS,
226 g_param_spec_boolean ("auto-flush-bus", "Auto Flush Bus",
227 "Whether to automatically flush the pipeline's bus when going "
228 "from READY into NULL state", DEFAULT_AUTO_FLUSH_BUS,
229 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
231 gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_pipeline_dispose);
233 gstelement_class->change_state =
234 GST_DEBUG_FUNCPTR (gst_pipeline_change_state);
235 gstelement_class->provide_clock =
236 GST_DEBUG_FUNCPTR (gst_pipeline_provide_clock_func);
237 gstbin_class->handle_message =
238 GST_DEBUG_FUNCPTR (gst_pipeline_handle_message);
242 gst_pipeline_init (GTypeInstance * instance, gpointer g_class)
244 GstPipeline *pipeline = GST_PIPELINE (instance);
247 pipeline->priv = GST_PIPELINE_GET_PRIVATE (pipeline);
249 /* set default property values */
250 pipeline->priv->auto_flush_bus = DEFAULT_AUTO_FLUSH_BUS;
251 pipeline->delay = DEFAULT_DELAY;
253 /* create and set a default bus */
254 bus = gst_bus_new ();
256 /* FIXME, disabled for 0.10.5 release as it caused to many regressions */
257 /* Start our bus in flushing if appropriate */
258 if (pipeline->priv->auto_flush_bus)
259 gst_bus_set_flushing (bus, TRUE);
262 gst_element_set_bus (GST_ELEMENT_CAST (pipeline), bus);
263 GST_DEBUG_OBJECT (pipeline, "set bus %" GST_PTR_FORMAT " on pipeline", bus);
264 gst_object_unref (bus);
268 gst_pipeline_dispose (GObject * object)
270 GstPipeline *pipeline = GST_PIPELINE (object);
271 GstClock **clock_p = &pipeline->fixed_clock;
273 GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, pipeline, "dispose");
275 /* clear and unref any fixed clock */
276 gst_object_replace ((GstObject **) clock_p, NULL);
278 G_OBJECT_CLASS (parent_class)->dispose (object);
282 gst_pipeline_set_property (GObject * object, guint prop_id,
283 const GValue * value, GParamSpec * pspec)
285 GstPipeline *pipeline = GST_PIPELINE (object);
289 gst_pipeline_set_delay (pipeline, g_value_get_uint64 (value));
291 case PROP_AUTO_FLUSH_BUS:
292 gst_pipeline_set_auto_flush_bus (pipeline, g_value_get_boolean (value));
295 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
301 gst_pipeline_get_property (GObject * object, guint prop_id,
302 GValue * value, GParamSpec * pspec)
304 GstPipeline *pipeline = GST_PIPELINE (object);
308 g_value_set_uint64 (value, gst_pipeline_get_delay (pipeline));
310 case PROP_AUTO_FLUSH_BUS:
311 g_value_set_boolean (value, gst_pipeline_get_auto_flush_bus (pipeline));
314 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
319 /* set the stream time to 0 */
321 reset_stream_time (GstPipeline * pipeline)
323 GST_OBJECT_LOCK (pipeline);
324 if (pipeline->stream_time != GST_CLOCK_TIME_NONE) {
325 GST_DEBUG_OBJECT (pipeline, "reset stream_time to 0");
326 pipeline->stream_time = 0;
327 pipeline->priv->update_stream_time = TRUE;
329 GST_DEBUG_OBJECT (pipeline, "application asked to not reset stream_time");
331 GST_OBJECT_UNLOCK (pipeline);
336 * @name: name of new pipeline
338 * Create a new pipeline with the given name.
340 * Returns: newly created GstPipeline
345 gst_pipeline_new (const gchar * name)
347 return gst_element_factory_make ("pipeline", name);
351 static GstStateChangeReturn
352 gst_pipeline_change_state (GstElement * element, GstStateChange transition)
354 GstStateChangeReturn result = GST_STATE_CHANGE_SUCCESS;
355 GstPipeline *pipeline = GST_PIPELINE (element);
358 switch (transition) {
359 case GST_STATE_CHANGE_NULL_TO_READY:
360 GST_OBJECT_LOCK (element);
362 gst_bus_set_flushing (element->bus, FALSE);
363 GST_OBJECT_UNLOCK (element);
365 case GST_STATE_CHANGE_READY_TO_PAUSED:
366 GST_OBJECT_LOCK (element);
367 pipeline->priv->update_clock = TRUE;
368 GST_OBJECT_UNLOCK (element);
370 case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
372 GstClockTime new_base_time;
373 GstClockTime start_time, stream_time, delay;
374 gboolean new_clock, update_stream_time, update_clock;
377 GST_DEBUG_OBJECT (element, "selecting clock and base_time");
379 GST_OBJECT_LOCK (element);
380 cur_clock = element->clock;
382 gst_object_ref (cur_clock);
383 stream_time = pipeline->stream_time;
384 update_stream_time = pipeline->priv->update_stream_time;
385 update_clock = pipeline->priv->update_clock;
386 pipeline->priv->update_stream_time = FALSE;
387 pipeline->priv->update_clock = FALSE;
388 delay = pipeline->delay;
389 GST_OBJECT_UNLOCK (element);
391 /* stream time changed, either with a PAUSED or a flush, we need to check
392 * if there is a new clock & update the base time */
393 if (update_stream_time) {
394 GST_DEBUG_OBJECT (pipeline, "Need to update stream_time");
396 /* when going to PLAYING, select a clock when needed. If we just got
397 * flushed, we don't reselect the clock. */
399 GST_DEBUG_OBJECT (pipeline, "Need to update clock.");
400 clock = gst_element_provide_clock (element);
402 GST_DEBUG_OBJECT (pipeline,
403 "Don't need to update clock, using old clock.");
404 clock = gst_object_ref (cur_clock);
407 new_clock = (clock != cur_clock);
410 start_time = gst_clock_get_time (clock);
412 GST_DEBUG ("no clock, using base time of NONE");
413 start_time = GST_CLOCK_TIME_NONE;
414 new_base_time = GST_CLOCK_TIME_NONE;
418 /* now distribute the clock (which could be NULL). If some
419 * element refuses the clock, this will return FALSE and
420 * we effectively fail the state change. */
421 if (!gst_element_set_clock (element, clock))
424 /* if we selected and distributed a new clock, let the app
426 gst_element_post_message (element,
427 gst_message_new_new_clock (GST_OBJECT_CAST (element), clock));
431 gst_object_unref (clock);
433 if (stream_time != GST_CLOCK_TIME_NONE
434 && start_time != GST_CLOCK_TIME_NONE) {
435 new_base_time = start_time - stream_time + delay;
436 GST_DEBUG_OBJECT (element,
437 "stream_time=%" GST_TIME_FORMAT ", now=%" GST_TIME_FORMAT
438 ", base_time %" GST_TIME_FORMAT,
439 GST_TIME_ARGS (stream_time), GST_TIME_ARGS (start_time),
440 GST_TIME_ARGS (new_base_time));
442 new_base_time = GST_CLOCK_TIME_NONE;
444 if (new_base_time != GST_CLOCK_TIME_NONE)
445 gst_element_set_base_time (element, new_base_time);
447 GST_DEBUG_OBJECT (pipeline,
448 "NOT adjusting base_time because stream_time is NONE");
450 GST_DEBUG_OBJECT (pipeline,
451 "NOT adjusting base_time because we selected one before");
455 gst_object_unref (cur_clock);
458 case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
460 case GST_STATE_CHANGE_PAUSED_TO_READY:
461 case GST_STATE_CHANGE_READY_TO_NULL:
465 result = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
467 switch (transition) {
468 case GST_STATE_CHANGE_NULL_TO_READY:
470 case GST_STATE_CHANGE_READY_TO_PAUSED:
472 reset_stream_time (pipeline);
475 case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
477 case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
478 GST_OBJECT_LOCK (element);
479 if ((clock = element->clock)) {
482 gst_object_ref (clock);
483 GST_OBJECT_UNLOCK (element);
485 /* calculate the time when we stopped */
486 now = gst_clock_get_time (clock);
487 gst_object_unref (clock);
489 GST_OBJECT_LOCK (element);
490 /* store the current stream time */
491 if (pipeline->stream_time != GST_CLOCK_TIME_NONE) {
492 pipeline->stream_time = now - element->base_time;
493 /* we went to PAUSED, when going to PLAYING select clock and new
495 pipeline->priv->update_stream_time = TRUE;
496 pipeline->priv->update_clock = TRUE;
499 GST_DEBUG_OBJECT (element,
500 "stream_time=%" GST_TIME_FORMAT ", now=%" GST_TIME_FORMAT
501 ", base_time %" GST_TIME_FORMAT,
502 GST_TIME_ARGS (pipeline->stream_time), GST_TIME_ARGS (now),
503 GST_TIME_ARGS (element->base_time));
505 GST_OBJECT_UNLOCK (element);
507 case GST_STATE_CHANGE_PAUSED_TO_READY:
509 case GST_STATE_CHANGE_READY_TO_NULL:
514 /* grab some stuff before we release the lock to flush out the bus */
515 GST_OBJECT_LOCK (element);
516 if ((bus = element->bus))
517 gst_object_ref (bus);
518 auto_flush = pipeline->priv->auto_flush_bus;
519 GST_OBJECT_UNLOCK (element);
523 gst_bus_set_flushing (bus, TRUE);
525 GST_INFO_OBJECT (element, "not flushing bus, auto-flushing disabled");
527 gst_object_unref (bus);
537 /* we generate this error when the selected clock was not
538 * accepted by some element */
539 GST_ELEMENT_ERROR (pipeline, CORE, CLOCK,
540 (_("Selected clock cannot be used in pipeline.")),
541 ("Pipeline cannot operate with selected clock"));
542 GST_DEBUG_OBJECT (pipeline,
543 "Pipeline cannot operate with selected clock %p", clock);
545 gst_object_unref (clock);
546 return GST_STATE_CHANGE_FAILURE;
550 /* intercept the bus messages from our children. We watch for the ASYNC_START
551 * message with is posted by the elements (sinks) that require a reset of the
552 * running_time after a flush. ASYNC_START also brings the pipeline back into
553 * the PAUSED, pending PAUSED state. When the ASYNC_DONE message is received the
554 * pipeline will redistribute the new base_time and will bring the elements back
555 * to the desired state of the pipeline. */
557 gst_pipeline_handle_message (GstBin * bin, GstMessage * message)
559 GstPipeline *pipeline = GST_PIPELINE_CAST (bin);
561 switch (GST_MESSAGE_TYPE (message)) {
562 case GST_MESSAGE_ASYNC_START:
564 gboolean new_base_time;
566 gst_message_parse_async_start (message, &new_base_time);
568 /* reset our stream time if we need to distribute a new base_time to the
571 reset_stream_time (pipeline);
578 GST_BIN_CLASS (parent_class)->handle_message (bin, message);
582 * gst_pipeline_get_bus:
583 * @pipeline: a #GstPipeline
585 * Gets the #GstBus of @pipeline. The bus allows applications to receive #GstMessages.
587 * Returns: a #GstBus, unref after usage.
592 gst_pipeline_get_bus (GstPipeline * pipeline)
594 return gst_element_get_bus (GST_ELEMENT (pipeline));
598 * gst_pipeline_set_new_stream_time:
599 * @pipeline: a #GstPipeline
600 * @time: the new stream time to set
602 * Set the new stream time of @pipeline to @time. The stream time is used to
603 * set the base time on the elements (see gst_element_set_base_time())
604 * in the PAUSED->PLAYING state transition.
606 * Setting @time to #GST_CLOCK_TIME_NONE will disable the pipeline's management
607 * of element base time. The application will then be responsible for
608 * performing base time distribution. This is sometimes useful if you want to
609 * synchronize capture from multiple pipelines, and you can also ensure that the
610 * pipelines have the same clock.
615 gst_pipeline_set_new_stream_time (GstPipeline * pipeline, GstClockTime time)
617 g_return_if_fail (GST_IS_PIPELINE (pipeline));
619 GST_OBJECT_LOCK (pipeline);
620 pipeline->stream_time = time;
621 pipeline->priv->update_stream_time = TRUE;
622 GST_OBJECT_UNLOCK (pipeline);
624 GST_DEBUG_OBJECT (pipeline, "set new stream_time to %" GST_TIME_FORMAT,
625 GST_TIME_ARGS (time));
627 if (time == GST_CLOCK_TIME_NONE)
628 GST_DEBUG_OBJECT (pipeline, "told not to adjust base_time");
632 * gst_pipeline_get_last_stream_time:
633 * @pipeline: a #GstPipeline
635 * Gets the last stream time of @pipeline. If the pipeline is PLAYING,
636 * the returned time is the stream time used to configure the element's
637 * base time in the PAUSED->PLAYING state. If the pipeline is PAUSED, the
638 * returned time is the stream time when the pipeline was paused.
640 * This function returns #GST_CLOCK_TIME_NONE if the pipeline was
641 * configured to not handle the management of the element's base time
642 * (see gst_pipeline_set_new_stream_time()).
644 * Returns: a #GstClockTime.
649 gst_pipeline_get_last_stream_time (GstPipeline * pipeline)
653 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), GST_CLOCK_TIME_NONE);
655 GST_OBJECT_LOCK (pipeline);
656 result = pipeline->stream_time;
657 GST_OBJECT_UNLOCK (pipeline);
663 gst_pipeline_provide_clock_func (GstElement * element)
665 GstClock *clock = NULL;
666 GstPipeline *pipeline = GST_PIPELINE (element);
668 /* if we have a fixed clock, use that one */
669 GST_OBJECT_LOCK (pipeline);
670 if (GST_OBJECT_FLAG_IS_SET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK)) {
671 clock = pipeline->fixed_clock;
673 gst_object_ref (clock);
674 GST_OBJECT_UNLOCK (pipeline);
676 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using fixed clock %p (%s)",
677 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
679 GST_OBJECT_UNLOCK (pipeline);
680 /* let the parent bin select a clock */
682 GST_ELEMENT_CLASS (parent_class)->provide_clock (GST_ELEMENT
684 /* no clock, use a system clock */
686 clock = gst_system_clock_obtain ();
688 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline obtained system clock: %p (%s)",
689 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
691 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline obtained clock: %p (%s)",
692 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
699 * gst_pipeline_get_clock:
700 * @pipeline: a #GstPipeline
702 * Gets the current clock used by @pipeline.
704 * Returns: a #GstClock, unref after usage.
707 gst_pipeline_get_clock (GstPipeline * pipeline)
709 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), NULL);
711 return gst_pipeline_provide_clock_func (GST_ELEMENT (pipeline));
716 * gst_pipeline_use_clock:
717 * @pipeline: a #GstPipeline
718 * @clock: the clock to use
720 * Force @pipeline to use the given @clock. The pipeline will
721 * always use the given clock even if new clock providers are added
724 * If @clock is NULL all clocking will be disabled which will make
725 * the pipeline run as fast as possible.
730 gst_pipeline_use_clock (GstPipeline * pipeline, GstClock * clock)
734 g_return_if_fail (GST_IS_PIPELINE (pipeline));
736 GST_OBJECT_LOCK (pipeline);
737 GST_OBJECT_FLAG_SET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK);
739 clock_p = &pipeline->fixed_clock;
740 gst_object_replace ((GstObject **) clock_p, (GstObject *) clock);
741 GST_OBJECT_UNLOCK (pipeline);
743 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using fixed clock %p (%s)", clock,
744 (clock ? GST_OBJECT_NAME (clock) : "nil"));
748 * gst_pipeline_set_clock:
749 * @pipeline: a #GstPipeline
750 * @clock: the clock to set
752 * Set the clock for @pipeline. The clock will be distributed
753 * to all the elements managed by the pipeline.
755 * Returns: TRUE if the clock could be set on the pipeline. FALSE if
756 * some element did not accept the clock.
761 gst_pipeline_set_clock (GstPipeline * pipeline, GstClock * clock)
763 g_return_val_if_fail (pipeline != NULL, FALSE);
764 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), FALSE);
766 return GST_ELEMENT_CLASS (parent_class)->set_clock (GST_ELEMENT (pipeline),
771 * gst_pipeline_auto_clock:
772 * @pipeline: a #GstPipeline
774 * Let @pipeline select a clock automatically. This is the default
777 * Use this function if you previous forced a fixed clock with
778 * gst_pipeline_use_clock() and want to restore the default
779 * pipeline clock selection algorithm.
784 gst_pipeline_auto_clock (GstPipeline * pipeline)
788 g_return_if_fail (pipeline != NULL);
789 g_return_if_fail (GST_IS_PIPELINE (pipeline));
791 GST_OBJECT_LOCK (pipeline);
792 GST_OBJECT_FLAG_UNSET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK);
794 clock_p = &pipeline->fixed_clock;
795 gst_object_replace ((GstObject **) clock_p, NULL);
796 GST_OBJECT_UNLOCK (pipeline);
798 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using automatic clock");
802 * gst_pipeline_set_delay:
803 * @pipeline: a #GstPipeline
806 * Set the expected delay needed for all elements to perform the
807 * PAUSED to PLAYING state change. @delay will be added to the
808 * base time of the elements so that they wait an additional @delay
809 * amount of time before starting to process buffers and cannot be
810 * #GST_CLOCK_TIME_NONE.
812 * This option is used for tuning purposes and should normally not be
820 gst_pipeline_set_delay (GstPipeline * pipeline, GstClockTime delay)
822 g_return_if_fail (GST_IS_PIPELINE (pipeline));
823 g_return_if_fail (delay != GST_CLOCK_TIME_NONE);
825 GST_OBJECT_LOCK (pipeline);
826 pipeline->delay = delay;
827 GST_OBJECT_UNLOCK (pipeline);
831 * gst_pipeline_get_delay:
832 * @pipeline: a #GstPipeline
834 * Get the configured delay (see gst_pipeline_set_delay()).
836 * Returns: The configured delay.
843 gst_pipeline_get_delay (GstPipeline * pipeline)
847 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), GST_CLOCK_TIME_NONE);
849 GST_OBJECT_LOCK (pipeline);
850 res = pipeline->delay;
851 GST_OBJECT_UNLOCK (pipeline);
857 * gst_pipeline_set_auto_flush_bus:
858 * @pipeline: a #GstPipeline
859 * @auto_flush: whether or not to automatically flush the bus when
860 * the pipeline goes from READY to NULL state
862 * Usually, when a pipeline goes from READY to NULL state, it automatically
863 * flushes all pending messages on the bus, which is done for refcounting
864 * purposes, to break circular references.
866 * This means that applications that update state using (async) bus messages
867 * (e.g. do certain things when a pipeline goes from PAUSED to READY) might
868 * not get to see messages when the pipeline is shut down, because they might
869 * be flushed before they can be dispatched in the main thread. This behaviour
870 * can be disabled using this function.
872 * It is important that all messages on the bus are handled when the
873 * automatic flushing is disabled else memory leaks will be introduced.
880 gst_pipeline_set_auto_flush_bus (GstPipeline * pipeline, gboolean auto_flush)
882 g_return_if_fail (GST_IS_PIPELINE (pipeline));
884 GST_OBJECT_LOCK (pipeline);
885 pipeline->priv->auto_flush_bus = auto_flush;
886 GST_OBJECT_UNLOCK (pipeline);
890 * gst_pipeline_get_auto_flush_bus:
891 * @pipeline: a #GstPipeline
893 * Check if @pipeline will automatically flush messages when going to
896 * Returns: whether the pipeline will automatically flush its bus when
897 * going from READY to NULL state or not.
904 gst_pipeline_get_auto_flush_bus (GstPipeline * pipeline)
908 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), FALSE);
910 GST_OBJECT_LOCK (pipeline);
911 res = pipeline->priv->auto_flush_bus;
912 GST_OBJECT_UNLOCK (pipeline);