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., 51 Franklin St, Fifth Floor,
20 * Boston, MA 02110-1301, USA.
25 * @short_description: Top-level bin with clocking and bus management
27 * @see_also: #GstElement, #GstBin, #GstClock, #GstBus
29 * A #GstPipeline is a special #GstBin used as the toplevel container for
30 * the filter graph. The #GstPipeline will manage the selection and
31 * distribution of a global #GstClock as well as provide a #GstBus to the
34 * gst_pipeline_new() is used to create a pipeline. when you are done with
35 * the pipeline, use gst_object_unref() to free its resources including all
36 * added #GstElement objects (if not otherwise referenced).
38 * Elements are added and removed from the pipeline using the #GstBin
39 * methods like gst_bin_add() and gst_bin_remove() (see #GstBin).
41 * Before changing the state of the #GstPipeline (see #GstElement) a #GstBus
42 * can be retrieved with gst_pipeline_get_bus(). This bus can then be
43 * used to receive #GstMessage from the elements in the pipeline.
45 * By default, a #GstPipeline will automatically flush the pending #GstBus
46 * messages when going to the NULL state to ensure that no circular
47 * references exist when no messages are read from the #GstBus. This
48 * behaviour can be changed with gst_pipeline_set_auto_flush_bus().
50 * When the #GstPipeline performs the PAUSED to PLAYING state change it will
51 * select a clock for the elements. The clock selection algorithm will by
52 * default select a clock provided by an element that is most upstream
53 * (closest to the source). For live pipelines (ones that return
54 * #GST_STATE_CHANGE_NO_PREROLL from the gst_element_set_state() call) this
55 * will select the clock provided by the live source. For normal pipelines
56 * this will select a clock provided by the sinks (most likely the audio
57 * sink). If no element provides a clock, a default #GstSystemClock is used.
59 * The clock selection can be controlled with the gst_pipeline_use_clock()
60 * method, which will enforce a given clock on the pipeline. With
61 * gst_pipeline_auto_clock() the default clock selection algorithm can be
64 * A #GstPipeline maintains a running time for the elements. The running
65 * time is defined as the difference between the current clock time and
66 * the base time. When the pipeline goes to READY or a flushing seek is
67 * performed on it, the running time is reset to 0. When the pipeline is
68 * set from PLAYING to PAUSED, the current clock time is sampled and used to
69 * configure the base time for the elements when the pipeline is set
70 * to PLAYING again. The effect is that the running time (as the difference
71 * between the clock time and the base time) will count how much time was spent
72 * in the PLAYING state. This default behaviour can be changed with the
73 * gst_element_set_start_time() method.
75 * Last reviewed on 2012-03-29 (0.11.3)
78 #include "gst_private.h"
80 #include "gst-i18n-lib.h"
82 #include "gstpipeline.h"
84 #include "gstsystemclock.h"
87 GST_DEBUG_CATEGORY_STATIC (pipeline_debug);
88 #define GST_CAT_DEFAULT pipeline_debug
90 /* Pipeline signals and args */
97 #define DEFAULT_DELAY 0
98 #define DEFAULT_AUTO_FLUSH_BUS TRUE
107 #define GST_PIPELINE_GET_PRIVATE(obj) \
108 (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_PIPELINE, GstPipelinePrivate))
110 struct _GstPipelinePrivate
113 gboolean auto_flush_bus;
115 /* when we need to update stream_time or clock when going back to
117 GstClockTime last_start_time;
118 gboolean update_clock;
122 static void gst_pipeline_dispose (GObject * object);
123 static void gst_pipeline_set_property (GObject * object, guint prop_id,
124 const GValue * value, GParamSpec * pspec);
125 static void gst_pipeline_get_property (GObject * object, guint prop_id,
126 GValue * value, GParamSpec * pspec);
128 static GstClock *gst_pipeline_provide_clock_func (GstElement * element);
129 static GstStateChangeReturn gst_pipeline_change_state (GstElement * element,
130 GstStateChange transition);
132 static void gst_pipeline_handle_message (GstBin * bin, GstMessage * message);
134 /* static guint gst_pipeline_signals[LAST_SIGNAL] = { 0 }; */
138 GST_DEBUG_CATEGORY_INIT (pipeline_debug, "pipeline", GST_DEBUG_BOLD, \
139 "debugging info for the 'pipeline' container element"); \
142 #define gst_pipeline_parent_class parent_class
143 G_DEFINE_TYPE_WITH_CODE (GstPipeline, gst_pipeline, GST_TYPE_BIN, _do_init);
146 gst_pipeline_class_init (GstPipelineClass * klass)
148 GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
149 GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
150 GstBinClass *gstbin_class = GST_BIN_CLASS (klass);
152 g_type_class_add_private (klass, sizeof (GstPipelinePrivate));
154 gobject_class->set_property = gst_pipeline_set_property;
155 gobject_class->get_property = gst_pipeline_get_property;
160 * The expected delay needed for elements to spin up to the
161 * PLAYING state expressed in nanoseconds.
162 * see gst_pipeline_set_delay() for more information on this option.
164 g_object_class_install_property (gobject_class, PROP_DELAY,
165 g_param_spec_uint64 ("delay", "Delay",
166 "Expected delay needed for elements "
167 "to spin up to PLAYING in nanoseconds", 0, G_MAXUINT64, DEFAULT_DELAY,
168 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
171 * GstPipeline:auto-flush-bus:
173 * Whether or not to automatically flush all messages on the
174 * pipeline's bus when going from READY to NULL state. Please see
175 * gst_pipeline_set_auto_flush_bus() for more information on this option.
177 g_object_class_install_property (gobject_class, PROP_AUTO_FLUSH_BUS,
178 g_param_spec_boolean ("auto-flush-bus", "Auto Flush Bus",
179 "Whether to automatically flush the pipeline's bus when going "
180 "from READY into NULL state", DEFAULT_AUTO_FLUSH_BUS,
181 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
183 gobject_class->dispose = gst_pipeline_dispose;
185 gst_element_class_set_static_metadata (gstelement_class, "Pipeline object",
187 "Complete pipeline object",
188 "Erik Walthinsen <omega@cse.ogi.edu>, Wim Taymans <wim@fluendo.com>");
190 gstelement_class->change_state =
191 GST_DEBUG_FUNCPTR (gst_pipeline_change_state);
192 gstelement_class->provide_clock =
193 GST_DEBUG_FUNCPTR (gst_pipeline_provide_clock_func);
194 gstbin_class->handle_message =
195 GST_DEBUG_FUNCPTR (gst_pipeline_handle_message);
199 gst_pipeline_init (GstPipeline * pipeline)
203 pipeline->priv = GST_PIPELINE_GET_PRIVATE (pipeline);
205 /* set default property values */
206 pipeline->priv->auto_flush_bus = DEFAULT_AUTO_FLUSH_BUS;
207 pipeline->delay = DEFAULT_DELAY;
209 /* create and set a default bus */
210 bus = gst_bus_new ();
212 /* FIXME, disabled for 0.10.5 release as it caused to many regressions */
213 /* Start our bus in flushing if appropriate */
214 if (pipeline->priv->auto_flush_bus)
215 gst_bus_set_flushing (bus, TRUE);
218 gst_element_set_bus (GST_ELEMENT_CAST (pipeline), bus);
219 GST_DEBUG_OBJECT (pipeline, "set bus %" GST_PTR_FORMAT " on pipeline", bus);
220 gst_object_unref (bus);
224 gst_pipeline_dispose (GObject * object)
226 GstPipeline *pipeline = GST_PIPELINE (object);
227 GstClock **clock_p = &pipeline->fixed_clock;
229 GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, pipeline, "dispose");
231 /* clear and unref any fixed clock */
232 gst_object_replace ((GstObject **) clock_p, NULL);
234 G_OBJECT_CLASS (parent_class)->dispose (object);
238 gst_pipeline_set_property (GObject * object, guint prop_id,
239 const GValue * value, GParamSpec * pspec)
241 GstPipeline *pipeline = GST_PIPELINE (object);
245 gst_pipeline_set_delay (pipeline, g_value_get_uint64 (value));
247 case PROP_AUTO_FLUSH_BUS:
248 gst_pipeline_set_auto_flush_bus (pipeline, g_value_get_boolean (value));
251 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
257 gst_pipeline_get_property (GObject * object, guint prop_id,
258 GValue * value, GParamSpec * pspec)
260 GstPipeline *pipeline = GST_PIPELINE (object);
264 g_value_set_uint64 (value, gst_pipeline_get_delay (pipeline));
266 case PROP_AUTO_FLUSH_BUS:
267 g_value_set_boolean (value, gst_pipeline_get_auto_flush_bus (pipeline));
270 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
275 /* set the start_time to 0, this will cause us to select a new base_time and
276 * make the running_time start from 0 again. */
278 reset_start_time (GstPipeline * pipeline, GstClockTime start_time)
280 GST_OBJECT_LOCK (pipeline);
281 if (GST_ELEMENT_START_TIME (pipeline) != GST_CLOCK_TIME_NONE) {
282 GST_DEBUG_OBJECT (pipeline, "reset start_time to 0");
283 GST_ELEMENT_START_TIME (pipeline) = start_time;
284 pipeline->priv->last_start_time = -1;
286 GST_DEBUG_OBJECT (pipeline, "application asked to not reset stream_time");
288 GST_OBJECT_UNLOCK (pipeline);
293 * @name: (allow-none): name of new pipeline
295 * Create a new pipeline with the given name.
297 * Returns: (transfer floating): newly created GstPipeline
302 gst_pipeline_new (const gchar * name)
304 return gst_element_factory_make ("pipeline", name);
307 /* takes a snapshot of the running_time of the pipeline and store this as the
308 * element start_time. This is the time we will set as the running_time of the
309 * pipeline when we go to PLAYING next. */
311 pipeline_update_start_time (GstElement * element)
313 GstPipeline *pipeline = GST_PIPELINE_CAST (element);
316 GST_OBJECT_LOCK (element);
317 if ((clock = element->clock)) {
320 gst_object_ref (clock);
321 GST_OBJECT_UNLOCK (element);
323 /* calculate the time when we stopped */
324 now = gst_clock_get_time (clock);
325 gst_object_unref (clock);
327 GST_OBJECT_LOCK (element);
328 /* store the current running time */
329 if (GST_ELEMENT_START_TIME (pipeline) != GST_CLOCK_TIME_NONE) {
330 if (now != GST_CLOCK_TIME_NONE)
331 GST_ELEMENT_START_TIME (pipeline) = now - element->base_time;
333 GST_WARNING_OBJECT (element,
334 "Clock %s returned invalid time, can't calculate "
335 "running_time when going to the PAUSED state",
336 GST_OBJECT_NAME (clock));
338 /* we went to PAUSED, when going to PLAYING select clock and new
340 pipeline->priv->update_clock = TRUE;
342 GST_DEBUG_OBJECT (element,
343 "start_time=%" GST_TIME_FORMAT ", now=%" GST_TIME_FORMAT
344 ", base_time %" GST_TIME_FORMAT,
345 GST_TIME_ARGS (GST_ELEMENT_START_TIME (pipeline)),
346 GST_TIME_ARGS (now), GST_TIME_ARGS (element->base_time));
348 GST_OBJECT_UNLOCK (element);
352 static GstStateChangeReturn
353 gst_pipeline_change_state (GstElement * element, GstStateChange transition)
355 GstStateChangeReturn result = GST_STATE_CHANGE_SUCCESS;
356 GstPipeline *pipeline = GST_PIPELINE_CAST (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 now, start_time, last_start_time, delay;
374 gboolean 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 /* get the desired running_time of the first buffer aka the start_time */
384 start_time = GST_ELEMENT_START_TIME (pipeline);
385 last_start_time = pipeline->priv->last_start_time;
386 pipeline->priv->last_start_time = start_time;
387 /* see if we need to update the clock */
388 update_clock = pipeline->priv->update_clock;
389 pipeline->priv->update_clock = FALSE;
390 delay = pipeline->delay;
391 GST_OBJECT_UNLOCK (element);
393 /* running time changed, either with a PAUSED or a flush, we need to check
394 * if there is a new clock & update the base time */
395 /* only do this for top-level, however */
396 if (GST_OBJECT_PARENT (element) == NULL &&
397 (update_clock || last_start_time != start_time)) {
398 GST_DEBUG_OBJECT (pipeline, "Need to update start_time");
400 /* when going to PLAYING, select a clock when needed. If we just got
401 * flushed, we don't reselect the clock. */
403 GST_DEBUG_OBJECT (pipeline, "Need to update clock.");
404 clock = gst_element_provide_clock (element);
406 GST_DEBUG_OBJECT (pipeline,
407 "Don't need to update clock, using old clock.");
408 /* only try to ref if cur_clock is not NULL */
410 gst_object_ref (cur_clock);
415 now = gst_clock_get_time (clock);
417 GST_DEBUG_OBJECT (pipeline, "no clock, using base time of NONE");
418 now = GST_CLOCK_TIME_NONE;
421 if (clock != cur_clock) {
422 /* now distribute the clock (which could be NULL). If some
423 * element refuses the clock, this will return FALSE and
424 * we effectively fail the state change. */
425 if (!gst_element_set_clock (element, clock))
428 /* if we selected and distributed a new clock, let the app
430 gst_element_post_message (element,
431 gst_message_new_new_clock (GST_OBJECT_CAST (element), clock));
435 gst_object_unref (clock);
437 if (start_time != GST_CLOCK_TIME_NONE && now != GST_CLOCK_TIME_NONE) {
438 GstClockTime new_base_time = now - start_time + delay;
439 GST_DEBUG_OBJECT (element,
440 "start_time=%" GST_TIME_FORMAT ", now=%" GST_TIME_FORMAT
441 ", base_time %" GST_TIME_FORMAT,
442 GST_TIME_ARGS (start_time), GST_TIME_ARGS (now),
443 GST_TIME_ARGS (new_base_time));
445 gst_element_set_base_time (element, new_base_time);
447 GST_DEBUG_OBJECT (pipeline,
448 "NOT adjusting base_time because start_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 /* we take a start_time snapshot before calling the children state changes
462 * so that they know about when the pipeline PAUSED. */
463 pipeline_update_start_time (element);
466 case GST_STATE_CHANGE_PAUSED_TO_READY:
467 case GST_STATE_CHANGE_READY_TO_NULL:
471 result = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
473 switch (transition) {
474 case GST_STATE_CHANGE_NULL_TO_READY:
476 case GST_STATE_CHANGE_READY_TO_PAUSED:
478 /* READY to PAUSED starts running_time from 0 */
479 reset_start_time (pipeline, 0);
482 case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
484 case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
486 /* Take a new snapshot of the start_time after calling the state change on
487 * all children. This will be the running_time of the pipeline when we go
489 pipeline_update_start_time (element);
492 case GST_STATE_CHANGE_PAUSED_TO_READY:
494 case GST_STATE_CHANGE_READY_TO_NULL:
499 /* grab some stuff before we release the lock to flush out the bus */
500 GST_OBJECT_LOCK (element);
501 if ((bus = element->bus))
502 gst_object_ref (bus);
503 auto_flush = pipeline->priv->auto_flush_bus;
504 GST_OBJECT_UNLOCK (element);
508 gst_bus_set_flushing (bus, TRUE);
510 GST_INFO_OBJECT (element, "not flushing bus, auto-flushing disabled");
512 gst_object_unref (bus);
522 /* we generate this error when the selected clock was not
523 * accepted by some element */
524 GST_ELEMENT_ERROR (pipeline, CORE, CLOCK,
525 (_("Selected clock cannot be used in pipeline.")),
526 ("Pipeline cannot operate with selected clock"));
527 GST_DEBUG_OBJECT (pipeline,
528 "Pipeline cannot operate with selected clock %p", clock);
530 gst_object_unref (clock);
531 return GST_STATE_CHANGE_FAILURE;
535 /* intercept the bus messages from our children. We watch for the ASYNC_START
536 * message with is posted by the elements (sinks) that require a reset of the
537 * running_time after a flush. ASYNC_START also brings the pipeline back into
538 * the PAUSED, pending PAUSED state. When the ASYNC_DONE message is received the
539 * pipeline will redistribute the new base_time and will bring the elements back
540 * to the desired state of the pipeline. */
542 gst_pipeline_handle_message (GstBin * bin, GstMessage * message)
544 GstPipeline *pipeline = GST_PIPELINE_CAST (bin);
546 switch (GST_MESSAGE_TYPE (message)) {
547 case GST_MESSAGE_RESET_TIME:
549 GstClockTime running_time;
551 gst_message_parse_reset_time (message, &running_time);
553 /* reset our running time if we need to distribute a new base_time to the
555 reset_start_time (pipeline, running_time);
558 case GST_MESSAGE_CLOCK_LOST:
562 gst_message_parse_clock_lost (message, &clock);
564 GST_OBJECT_LOCK (bin);
565 if (clock == GST_ELEMENT_CAST (bin)->clock) {
566 GST_DEBUG_OBJECT (bin, "Used clock '%s' got lost",
567 GST_OBJECT_NAME (clock));
568 pipeline->priv->update_clock = TRUE;
570 GST_OBJECT_UNLOCK (bin);
575 GST_BIN_CLASS (parent_class)->handle_message (bin, message);
579 * gst_pipeline_get_bus:
580 * @pipeline: a #GstPipeline
582 * Gets the #GstBus of @pipeline. The bus allows applications to receive
583 * #GstMessage packets.
585 * Returns: (transfer full): a #GstBus, unref after usage.
590 gst_pipeline_get_bus (GstPipeline * pipeline)
592 return gst_element_get_bus (GST_ELEMENT_CAST (pipeline));
596 gst_pipeline_provide_clock_func (GstElement * element)
598 GstClock *clock = NULL;
599 GstPipeline *pipeline = GST_PIPELINE (element);
601 /* if we have a fixed clock, use that one */
602 GST_OBJECT_LOCK (pipeline);
603 if (GST_OBJECT_FLAG_IS_SET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK)) {
604 clock = pipeline->fixed_clock;
606 gst_object_ref (clock);
607 GST_OBJECT_UNLOCK (pipeline);
609 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using fixed clock %p (%s)",
610 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
612 GST_OBJECT_UNLOCK (pipeline);
613 /* let the parent bin select a clock */
615 GST_ELEMENT_CLASS (parent_class)->provide_clock (GST_ELEMENT
617 /* no clock, use a system clock */
619 clock = gst_system_clock_obtain ();
621 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline obtained system clock: %p (%s)",
622 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
624 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline obtained clock: %p (%s)",
625 clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
632 * gst_pipeline_get_clock:
633 * @pipeline: a #GstPipeline
635 * Gets the current clock used by @pipeline.
637 * Returns: (transfer full): a #GstClock, unref after usage.
640 gst_pipeline_get_clock (GstPipeline * pipeline)
642 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), NULL);
644 return gst_pipeline_provide_clock_func (GST_ELEMENT_CAST (pipeline));
649 * gst_pipeline_use_clock:
650 * @pipeline: a #GstPipeline
651 * @clock: (transfer none): the clock to use
653 * Force @pipeline to use the given @clock. The pipeline will
654 * always use the given clock even if new clock providers are added
657 * If @clock is NULL all clocking will be disabled which will make
658 * the pipeline run as fast as possible.
663 gst_pipeline_use_clock (GstPipeline * pipeline, GstClock * clock)
667 g_return_if_fail (GST_IS_PIPELINE (pipeline));
669 GST_OBJECT_LOCK (pipeline);
670 GST_OBJECT_FLAG_SET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK);
672 clock_p = &pipeline->fixed_clock;
673 gst_object_replace ((GstObject **) clock_p, (GstObject *) clock);
674 GST_OBJECT_UNLOCK (pipeline);
676 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using fixed clock %p (%s)", clock,
677 (clock ? GST_OBJECT_NAME (clock) : "nil"));
681 * gst_pipeline_set_clock:
682 * @pipeline: a #GstPipeline
683 * @clock: (transfer none): the clock to set
685 * Set the clock for @pipeline. The clock will be distributed
686 * to all the elements managed by the pipeline.
688 * Returns: TRUE if the clock could be set on the pipeline. FALSE if
689 * some element did not accept the clock.
694 gst_pipeline_set_clock (GstPipeline * pipeline, GstClock * clock)
696 g_return_val_if_fail (pipeline != NULL, FALSE);
697 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), FALSE);
700 GST_ELEMENT_CLASS (parent_class)->set_clock (GST_ELEMENT_CAST (pipeline),
705 * gst_pipeline_auto_clock:
706 * @pipeline: a #GstPipeline
708 * Let @pipeline select a clock automatically. This is the default
711 * Use this function if you previous forced a fixed clock with
712 * gst_pipeline_use_clock() and want to restore the default
713 * pipeline clock selection algorithm.
718 gst_pipeline_auto_clock (GstPipeline * pipeline)
722 g_return_if_fail (pipeline != NULL);
723 g_return_if_fail (GST_IS_PIPELINE (pipeline));
725 GST_OBJECT_LOCK (pipeline);
726 GST_OBJECT_FLAG_UNSET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK);
728 clock_p = &pipeline->fixed_clock;
729 gst_object_replace ((GstObject **) clock_p, NULL);
730 GST_OBJECT_UNLOCK (pipeline);
732 GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using automatic clock");
736 * gst_pipeline_set_delay:
737 * @pipeline: a #GstPipeline
740 * Set the expected delay needed for all elements to perform the
741 * PAUSED to PLAYING state change. @delay will be added to the
742 * base time of the elements so that they wait an additional @delay
743 * amount of time before starting to process buffers and cannot be
744 * #GST_CLOCK_TIME_NONE.
746 * This option is used for tuning purposes and should normally not be
752 gst_pipeline_set_delay (GstPipeline * pipeline, GstClockTime delay)
754 g_return_if_fail (GST_IS_PIPELINE (pipeline));
755 g_return_if_fail (delay != GST_CLOCK_TIME_NONE);
757 GST_OBJECT_LOCK (pipeline);
758 pipeline->delay = delay;
759 GST_OBJECT_UNLOCK (pipeline);
763 * gst_pipeline_get_delay:
764 * @pipeline: a #GstPipeline
766 * Get the configured delay (see gst_pipeline_set_delay()).
768 * Returns: The configured delay.
773 gst_pipeline_get_delay (GstPipeline * pipeline)
777 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), GST_CLOCK_TIME_NONE);
779 GST_OBJECT_LOCK (pipeline);
780 res = pipeline->delay;
781 GST_OBJECT_UNLOCK (pipeline);
787 * gst_pipeline_set_auto_flush_bus:
788 * @pipeline: a #GstPipeline
789 * @auto_flush: whether or not to automatically flush the bus when
790 * the pipeline goes from READY to NULL state
792 * Usually, when a pipeline goes from READY to NULL state, it automatically
793 * flushes all pending messages on the bus, which is done for refcounting
794 * purposes, to break circular references.
796 * This means that applications that update state using (async) bus messages
797 * (e.g. do certain things when a pipeline goes from PAUSED to READY) might
798 * not get to see messages when the pipeline is shut down, because they might
799 * be flushed before they can be dispatched in the main thread. This behaviour
800 * can be disabled using this function.
802 * It is important that all messages on the bus are handled when the
803 * automatic flushing is disabled else memory leaks will be introduced.
808 gst_pipeline_set_auto_flush_bus (GstPipeline * pipeline, gboolean auto_flush)
810 g_return_if_fail (GST_IS_PIPELINE (pipeline));
812 GST_OBJECT_LOCK (pipeline);
813 pipeline->priv->auto_flush_bus = auto_flush;
814 GST_OBJECT_UNLOCK (pipeline);
818 * gst_pipeline_get_auto_flush_bus:
819 * @pipeline: a #GstPipeline
821 * Check if @pipeline will automatically flush messages when going to
824 * Returns: whether the pipeline will automatically flush its bus when
825 * going from READY to NULL state or not.
830 gst_pipeline_get_auto_flush_bus (GstPipeline * pipeline)
834 g_return_val_if_fail (GST_IS_PIPELINE (pipeline), FALSE);
836 GST_OBJECT_LOCK (pipeline);
837 res = pipeline->priv->auto_flush_bus;
838 GST_OBJECT_UNLOCK (pipeline);