1 /* GStreamer concat element
3 * Copyright (c) 2014 Sebastian Dröge <sebastian@centricular.com>
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Library General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Library General Public License for more details.
15 * You should have received a copy of the GNU Library General Public
16 * License along with this library; if not, write to the
17 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
18 * Boston, MA 02110-1301, USA.
22 * SECTION:element-concat
23 * @see_also: #GstFunnel
25 * Concatenates streams together to one continous stream.
27 * All streams but the current one are blocked until the current one
28 * finished with %GST_EVENT_EOS. Then the next stream is enabled, while
29 * keeping the running time continous for %GST_FORMAT_TIME segments or
30 * keeping the segment continous for %GST_FORMAT_BYTES segments.
32 * Streams are switched in the order in which the sinkpads were requested.
34 * By default, the stream segment's base values are adjusted to ensure
35 * the segment transitions between streams are continuous. In some cases,
36 * it may be desirable to turn off these adjustments (for example, because
37 * another downstream element like a streamsynchronizer adjusts the base
38 * values on its own). The adjust-value property can be used for this purpose.
41 * <title>Example launch line</title>
43 * gst-launch-1.0 concat name=c ! xvimagesink videotestsrc num-buffers=100 ! c. videotestsrc num-buffers=100 pattern=ball ! c.
44 * ]| Plays two video streams one after another.
52 #include "gstconcat.h"
54 GST_DEBUG_CATEGORY_STATIC (gst_concat_debug);
55 #define GST_CAT_DEFAULT gst_concat_debug
57 G_GNUC_INTERNAL GType gst_concat_pad_get_type (void);
59 #define GST_TYPE_CONCAT_PAD (gst_concat_pad_get_type())
60 #define GST_CONCAT_PAD(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_CONCAT_PAD, GstConcatPad))
61 #define GST_CONCAT_PAD_CAST(obj) ((GstConcatPad *)(obj))
62 #define GST_CONCAT_PAD_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_CONCAT_PAD, GstConcatPadClass))
63 #define GST_IS_CONCAT_PAD(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_CONCAT_PAD))
64 #define GST_IS_CONCAT_PAD_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_CONCAT_PAD))
66 typedef struct _GstConcatPad GstConcatPad;
67 typedef struct _GstConcatPadClass GstConcatPadClass;
75 /* Protected by the concat lock */
79 struct _GstConcatPadClass
84 G_DEFINE_TYPE (GstConcatPad, gst_concat_pad, GST_TYPE_PAD);
87 gst_concat_pad_class_init (GstConcatPadClass * klass)
92 gst_concat_pad_init (GstConcatPad * self)
94 gst_segment_init (&self->segment, GST_FORMAT_UNDEFINED);
95 self->flushing = FALSE;
98 static GstStaticPadTemplate concat_sink_template =
99 GST_STATIC_PAD_TEMPLATE ("sink_%u",
102 GST_STATIC_CAPS_ANY);
104 static GstStaticPadTemplate concat_src_template =
105 GST_STATIC_PAD_TEMPLATE ("src",
108 GST_STATIC_CAPS_ANY);
117 #define DEFAULT_ADJUST_BASE TRUE
120 GST_DEBUG_CATEGORY_INIT (gst_concat_debug, "concat", 0, "concat element");
121 #define gst_concat_parent_class parent_class
122 G_DEFINE_TYPE_WITH_CODE (GstConcat, gst_concat, GST_TYPE_ELEMENT, _do_init);
124 static void gst_concat_dispose (GObject * object);
125 static void gst_concat_finalize (GObject * object);
126 static void gst_concat_get_property (GObject * object,
127 guint prop_id, GValue * value, GParamSpec * pspec);
128 static void gst_concat_set_property (GObject * object,
129 guint prop_id, const GValue * value, GParamSpec * pspec);
131 static GstStateChangeReturn gst_concat_change_state (GstElement * element,
132 GstStateChange transition);
133 static GstPad *gst_concat_request_new_pad (GstElement * element,
134 GstPadTemplate * templ, const gchar * name, const GstCaps * caps);
135 static void gst_concat_release_pad (GstElement * element, GstPad * pad);
137 static GstFlowReturn gst_concat_sink_chain (GstPad * pad, GstObject * parent,
139 static gboolean gst_concat_sink_event (GstPad * pad, GstObject * parent,
141 static gboolean gst_concat_sink_query (GstPad * pad, GstObject * parent,
144 static gboolean gst_concat_src_event (GstPad * pad, GstObject * parent,
146 static gboolean gst_concat_src_query (GstPad * pad, GstObject * parent,
149 static gboolean gst_concat_switch_pad (GstConcat * self);
151 static void gst_concat_notify_active_pad (GstConcat * self);
153 static GParamSpec *pspec_active_pad = NULL;
156 gst_concat_class_init (GstConcatClass * klass)
158 GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
159 GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
161 gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_concat_dispose);
162 gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_concat_finalize);
164 gobject_class->get_property = gst_concat_get_property;
165 gobject_class->set_property = gst_concat_set_property;
167 pspec_active_pad = g_param_spec_object ("active-pad", "Active pad",
168 "Currently active src pad", GST_TYPE_PAD, G_PARAM_READABLE |
169 G_PARAM_STATIC_STRINGS);
170 g_object_class_install_property (gobject_class, PROP_ACTIVE_PAD,
172 g_object_class_install_property (gobject_class, PROP_ADJUST_BASE,
173 g_param_spec_boolean ("adjust-base", "Adjust segment base",
174 "Adjust the base value of segments to ensure they are adjacent",
175 DEFAULT_ADJUST_BASE, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
177 gst_element_class_set_static_metadata (gstelement_class,
178 "Concat", "Generic", "Concatenate multiple streams",
179 "Sebastian Dröge <sebastian@centricular.com>");
181 gst_element_class_add_pad_template (gstelement_class,
182 gst_static_pad_template_get (&concat_sink_template));
183 gst_element_class_add_pad_template (gstelement_class,
184 gst_static_pad_template_get (&concat_src_template));
186 gstelement_class->request_new_pad =
187 GST_DEBUG_FUNCPTR (gst_concat_request_new_pad);
188 gstelement_class->release_pad = GST_DEBUG_FUNCPTR (gst_concat_release_pad);
189 gstelement_class->change_state = GST_DEBUG_FUNCPTR (gst_concat_change_state);
193 gst_concat_init (GstConcat * self)
195 g_mutex_init (&self->lock);
196 g_cond_init (&self->cond);
198 self->srcpad = gst_pad_new_from_static_template (&concat_src_template, "src");
199 gst_pad_set_event_function (self->srcpad,
200 GST_DEBUG_FUNCPTR (gst_concat_src_event));
201 gst_pad_set_query_function (self->srcpad,
202 GST_DEBUG_FUNCPTR (gst_concat_src_query));
203 gst_pad_use_fixed_caps (self->srcpad);
205 gst_element_add_pad (GST_ELEMENT (self), self->srcpad);
207 self->adjust_base = DEFAULT_ADJUST_BASE;
211 gst_concat_dispose (GObject * object)
213 GstConcat *self = GST_CONCAT (object);
216 gst_object_replace ((GstObject **) & self->current_sinkpad, NULL);
219 for (item = GST_ELEMENT_PADS (object); item; item = g_list_next (item)) {
220 GstPad *pad = GST_PAD (item->data);
222 if (GST_PAD_IS_SINK (pad)) {
223 gst_element_release_request_pad (GST_ELEMENT (object), pad);
228 G_OBJECT_CLASS (parent_class)->dispose (object);
232 gst_concat_finalize (GObject * object)
234 GstConcat *self = GST_CONCAT (object);
236 g_mutex_clear (&self->lock);
237 g_cond_clear (&self->cond);
239 G_OBJECT_CLASS (parent_class)->finalize (object);
243 gst_concat_get_property (GObject * object, guint prop_id, GValue * value,
246 GstConcat *self = GST_CONCAT (object);
249 case PROP_ACTIVE_PAD:{
250 g_mutex_lock (&self->lock);
251 g_value_set_object (value, self->current_sinkpad);
252 g_mutex_unlock (&self->lock);
255 case PROP_ADJUST_BASE:{
256 g_mutex_lock (&self->lock);
257 g_value_set_boolean (value, self->adjust_base);
258 g_mutex_unlock (&self->lock);
262 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
268 gst_concat_set_property (GObject * object, guint prop_id, const GValue * value,
271 GstConcat *self = GST_CONCAT (object);
274 case PROP_ADJUST_BASE:{
275 g_mutex_lock (&self->lock);
276 self->adjust_base = g_value_get_boolean (value);
277 g_mutex_unlock (&self->lock);
281 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
287 gst_concat_request_new_pad (GstElement * element, GstPadTemplate * templ,
288 const gchar * name, const GstCaps * caps)
290 GstConcat *self = GST_CONCAT (element);
293 gboolean do_notify = FALSE;
295 GST_DEBUG_OBJECT (element, "requesting pad");
297 g_mutex_lock (&self->lock);
298 pad_name = g_strdup_printf ("sink_%u", self->pad_count);
300 g_mutex_unlock (&self->lock);
302 sinkpad = GST_PAD_CAST (g_object_new (GST_TYPE_CONCAT_PAD,
303 "name", pad_name, "direction", templ->direction, "template", templ,
307 gst_pad_set_chain_function (sinkpad,
308 GST_DEBUG_FUNCPTR (gst_concat_sink_chain));
309 gst_pad_set_event_function (sinkpad,
310 GST_DEBUG_FUNCPTR (gst_concat_sink_event));
311 gst_pad_set_query_function (sinkpad,
312 GST_DEBUG_FUNCPTR (gst_concat_sink_query));
313 GST_OBJECT_FLAG_SET (sinkpad, GST_PAD_FLAG_PROXY_CAPS);
314 GST_OBJECT_FLAG_SET (sinkpad, GST_PAD_FLAG_PROXY_ALLOCATION);
316 gst_pad_set_active (sinkpad, TRUE);
318 g_mutex_lock (&self->lock);
319 self->sinkpads = g_list_prepend (self->sinkpads, gst_object_ref (sinkpad));
320 if (!self->current_sinkpad) {
322 self->current_sinkpad = gst_object_ref (sinkpad);
324 g_mutex_unlock (&self->lock);
326 gst_element_add_pad (element, sinkpad);
329 gst_concat_notify_active_pad (self);
335 gst_concat_release_pad (GstElement * element, GstPad * pad)
337 GstConcat *self = GST_CONCAT (element);
338 GstConcatPad *spad = GST_CONCAT_PAD_CAST (pad);
340 gboolean current_pad_removed = FALSE;
341 gboolean eos = FALSE;
342 gboolean do_notify = FALSE;
344 GST_DEBUG_OBJECT (self, "releasing pad");
346 g_mutex_lock (&self->lock);
347 spad->flushing = TRUE;
348 g_cond_broadcast (&self->cond);
349 g_mutex_unlock (&self->lock);
351 gst_pad_set_active (pad, FALSE);
353 /* Now the pad is definitely not running anymore */
355 g_mutex_lock (&self->lock);
356 if (self->current_sinkpad == GST_PAD_CAST (spad)) {
357 eos = ! !gst_concat_switch_pad (self);
358 current_pad_removed = TRUE;
362 for (l = self->sinkpads; l; l = l->next) {
363 if ((gpointer) spad == l->data) {
364 gst_object_unref (spad);
365 self->sinkpads = g_list_delete_link (self->sinkpads, l);
369 g_mutex_unlock (&self->lock);
371 gst_element_remove_pad (GST_ELEMENT_CAST (self), pad);
374 gst_concat_notify_active_pad (self);
376 if (GST_STATE (self) > GST_STATE_READY) {
377 if (current_pad_removed && !eos)
378 gst_element_post_message (GST_ELEMENT_CAST (self),
379 gst_message_new_duration_changed (GST_OBJECT_CAST (self)));
381 /* FIXME: Sending EOS from application thread */
383 gst_pad_push_event (self->srcpad, gst_event_new_eos ());
387 /* Returns FALSE if flushing
388 * Must be called from the pad's streaming thread
391 gst_concat_pad_wait (GstConcatPad * spad, GstConcat * self)
393 g_mutex_lock (&self->lock);
394 if (spad->flushing) {
395 g_mutex_unlock (&self->lock);
396 GST_DEBUG_OBJECT (spad, "Flushing");
400 while (spad != GST_CONCAT_PAD_CAST (self->current_sinkpad)) {
401 GST_TRACE_OBJECT (spad, "Not the current sinkpad - waiting");
402 g_cond_wait (&self->cond, &self->lock);
403 if (spad->flushing) {
404 g_mutex_unlock (&self->lock);
405 GST_DEBUG_OBJECT (spad, "Flushing");
409 /* This pad can only become not the current sinkpad from
410 * a) This streaming thread (we hold the stream lock)
411 * b) Releasing the pad (takes the stream lock, see above)
413 * Unlocking here is thus safe and we can safely push
414 * serialized data to our srcpad
416 GST_DEBUG_OBJECT (spad, "Now the current sinkpad");
417 g_mutex_unlock (&self->lock);
423 gst_concat_sink_chain (GstPad * pad, GstObject * parent, GstBuffer * buffer)
426 GstConcat *self = GST_CONCAT (parent);
427 GstConcatPad *spad = GST_CONCAT_PAD (pad);
429 GST_LOG_OBJECT (pad, "received buffer %p", buffer);
431 if (!gst_concat_pad_wait (spad, self))
432 return GST_FLOW_FLUSHING;
434 if (self->last_stop == GST_CLOCK_TIME_NONE)
435 self->last_stop = spad->segment.start;
437 if (self->format == GST_FORMAT_TIME) {
438 GstClockTime start_time = GST_BUFFER_TIMESTAMP (buffer);
439 GstClockTime end_time = GST_CLOCK_TIME_NONE;
441 if (start_time != GST_CLOCK_TIME_NONE)
442 end_time = start_time;
443 if (GST_BUFFER_DURATION_IS_VALID (buffer))
444 end_time += GST_BUFFER_DURATION (buffer);
446 if (end_time != GST_CLOCK_TIME_NONE && end_time > self->last_stop)
447 self->last_stop = end_time;
449 self->last_stop += gst_buffer_get_size (buffer);
452 ret = gst_pad_push (self->srcpad, buffer);
454 GST_LOG_OBJECT (pad, "handled buffer %s", gst_flow_get_name (ret));
459 /* Returns FALSE if no further pad, must be called with concat lock */
461 gst_concat_switch_pad (GstConcat * self)
468 segment = GST_CONCAT_PAD (self->current_sinkpad)->segment;
470 last_stop = self->last_stop;
471 if (last_stop == GST_CLOCK_TIME_NONE)
472 last_stop = segment.stop;
473 if (last_stop == GST_CLOCK_TIME_NONE)
474 last_stop = segment.start;
475 g_assert (last_stop != GST_CLOCK_TIME_NONE);
477 if (last_stop > segment.stop)
478 last_stop = segment.stop;
480 if (segment.format == GST_FORMAT_TIME)
482 gst_segment_to_running_time (&segment, segment.format, last_stop);
484 last_stop += segment.start;
486 self->current_start_offset += last_stop;
488 for (l = self->sinkpads; l; l = l->next) {
489 if ((gpointer) self->current_sinkpad == l->data) {
491 GST_DEBUG_OBJECT (self,
492 "Switching from pad %" GST_PTR_FORMAT " to %" GST_PTR_FORMAT,
493 self->current_sinkpad, l ? l->data : NULL);
494 gst_object_unref (self->current_sinkpad);
495 self->current_sinkpad = l ? gst_object_ref (l->data) : NULL;
496 g_cond_broadcast (&self->cond);
501 next = self->current_sinkpad != NULL;
503 self->last_stop = GST_CLOCK_TIME_NONE;
509 gst_concat_notify_active_pad (GstConcat * self)
511 g_object_notify_by_pspec ((GObject *) self, pspec_active_pad);
515 gst_concat_sink_event (GstPad * pad, GstObject * parent, GstEvent * event)
517 GstConcat *self = GST_CONCAT (parent);
518 GstConcatPad *spad = GST_CONCAT_PAD_CAST (pad);
521 GST_LOG_OBJECT (pad, "received event %" GST_PTR_FORMAT, event);
523 switch (GST_EVENT_TYPE (event)) {
524 case GST_EVENT_STREAM_START:{
525 if (!gst_concat_pad_wait (spad, self)) {
527 gst_event_unref (event);
529 ret = gst_pad_event_default (pad, parent, event);
533 case GST_EVENT_SEGMENT:{
534 gboolean adjust_base;
536 /* Drop segment event, we create our own one */
537 gst_event_copy_segment (event, &spad->segment);
538 gst_event_unref (event);
540 g_mutex_lock (&self->lock);
541 adjust_base = self->adjust_base;
542 if (self->format == GST_FORMAT_UNDEFINED) {
543 if (spad->segment.format != GST_FORMAT_TIME
544 && spad->segment.format != GST_FORMAT_BYTES) {
545 g_mutex_unlock (&self->lock);
546 GST_ELEMENT_ERROR (self, CORE, FAILED, (NULL),
547 ("Can only operate in TIME or BYTES format"));
551 self->format = spad->segment.format;
552 GST_DEBUG_OBJECT (self, "Operating in %s format",
553 gst_format_get_name (self->format));
554 g_mutex_unlock (&self->lock);
555 } else if (self->format != spad->segment.format) {
556 g_mutex_unlock (&self->lock);
557 GST_ELEMENT_ERROR (self, CORE, FAILED, (NULL),
558 ("Operating in %s format but new pad has %s",
559 gst_format_get_name (self->format),
560 gst_format_get_name (spad->segment.format)));
563 g_mutex_unlock (&self->lock);
566 if (!gst_concat_pad_wait (spad, self)) {
569 GstSegment segment = spad->segment;
572 /* We know no duration */
573 segment.duration = -1;
575 /* Update segment values to be continous with last stream */
576 if (self->format == GST_FORMAT_TIME) {
577 segment.base += self->current_start_offset;
579 /* Shift start/stop byte position */
580 segment.start += self->current_start_offset;
581 if (segment.stop != -1)
582 segment.stop += self->current_start_offset;
586 gst_pad_push_event (self->srcpad, gst_event_new_segment (&segment));
591 gst_event_unref (event);
593 if (!gst_concat_pad_wait (spad, self)) {
598 g_mutex_lock (&self->lock);
599 next = gst_concat_switch_pad (self);
600 g_mutex_unlock (&self->lock);
603 gst_concat_notify_active_pad (self);
606 gst_pad_push_event (self->srcpad, gst_event_new_eos ());
608 gst_element_post_message (GST_ELEMENT_CAST (self),
609 gst_message_new_duration_changed (GST_OBJECT_CAST (self)));
614 case GST_EVENT_FLUSH_START:{
617 g_mutex_lock (&self->lock);
618 spad->flushing = TRUE;
619 g_cond_broadcast (&self->cond);
620 forward = (self->current_sinkpad == GST_PAD_CAST (spad));
621 g_mutex_unlock (&self->lock);
624 ret = gst_pad_event_default (pad, parent, event);
626 gst_event_unref (event);
629 case GST_EVENT_FLUSH_STOP:{
632 gst_segment_init (&spad->segment, GST_FORMAT_UNDEFINED);
633 spad->flushing = FALSE;
635 g_mutex_lock (&self->lock);
636 forward = (self->current_sinkpad == GST_PAD_CAST (spad));
637 g_mutex_unlock (&self->lock);
642 gst_event_parse_flush_stop (event, &reset_time);
644 GST_DEBUG_OBJECT (self,
645 "resetting start offset to 0 after flushing with reset_time = TRUE");
646 self->current_start_offset = 0;
648 ret = gst_pad_event_default (pad, parent, event);
650 gst_event_unref (event);
655 /* Wait for other serialized events before forwarding */
656 if (GST_EVENT_IS_SERIALIZED (event) && !gst_concat_pad_wait (spad, self)) {
657 gst_event_unref (event);
660 ret = gst_pad_event_default (pad, parent, event);
670 gst_concat_sink_query (GstPad * pad, GstObject * parent, GstQuery * query)
672 GstConcat *self = GST_CONCAT (parent);
673 GstConcatPad *spad = GST_CONCAT_PAD_CAST (pad);
676 GST_LOG_OBJECT (pad, "received query %" GST_PTR_FORMAT, query);
678 switch (GST_QUERY_TYPE (query)) {
680 /* Wait for other serialized queries before forwarding */
681 if (GST_QUERY_IS_SERIALIZED (query) && !gst_concat_pad_wait (spad, self)) {
684 ret = gst_pad_query_default (pad, parent, query);
693 gst_concat_src_event (GstPad * pad, GstObject * parent, GstEvent * event)
695 GstConcat *self = GST_CONCAT (parent);
698 GST_LOG_OBJECT (pad, "received event %" GST_PTR_FORMAT, event);
700 switch (GST_EVENT_TYPE (event)) {
701 case GST_EVENT_SEEK:{
702 GstPad *sinkpad = NULL;
704 g_mutex_lock (&self->lock);
705 if ((sinkpad = self->current_sinkpad))
706 gst_object_ref (sinkpad);
707 g_mutex_unlock (&self->lock);
709 ret = gst_pad_push_event (sinkpad, event);
710 gst_object_unref (sinkpad);
712 gst_event_unref (event);
719 GstClockTimeDiff diff;
720 GstClockTime timestamp;
723 gst_event_parse_qos (event, &type, &proportion, &diff, ×tamp);
724 gst_event_unref (event);
726 if (timestamp != GST_CLOCK_TIME_NONE
727 && timestamp > self->current_start_offset) {
728 timestamp -= self->current_start_offset;
729 event = gst_event_new_qos (type, proportion, diff, timestamp);
730 ret = gst_pad_push_event (self->current_sinkpad, event);
736 case GST_EVENT_FLUSH_STOP:{
739 gst_event_parse_flush_stop (event, &reset_time);
741 GST_DEBUG_OBJECT (self,
742 "resetting start offset to 0 after flushing with reset_time = TRUE");
743 self->current_start_offset = 0;
746 ret = gst_pad_event_default (pad, parent, event);
750 ret = gst_pad_event_default (pad, parent, event);
758 gst_concat_src_query (GstPad * pad, GstObject * parent, GstQuery * query)
762 GST_LOG_OBJECT (pad, "received query %" GST_PTR_FORMAT, query);
764 switch (GST_QUERY_TYPE (query)) {
766 ret = gst_pad_query_default (pad, parent, query);
774 reset_pad (const GValue * data, gpointer user_data)
776 GstPad *pad = g_value_get_object (data);
777 GstConcatPad *spad = GST_CONCAT_PAD_CAST (pad);
779 gst_segment_init (&spad->segment, GST_FORMAT_UNDEFINED);
780 spad->flushing = FALSE;
784 unblock_pad (const GValue * data, gpointer user_data)
786 GstPad *pad = g_value_get_object (data);
787 GstConcatPad *spad = GST_CONCAT_PAD_CAST (pad);
789 spad->flushing = TRUE;
792 static GstStateChangeReturn
793 gst_concat_change_state (GstElement * element, GstStateChange transition)
795 GstConcat *self = GST_CONCAT (element);
796 GstStateChangeReturn ret;
798 switch (transition) {
799 case GST_STATE_CHANGE_READY_TO_PAUSED:{
800 self->format = GST_FORMAT_UNDEFINED;
801 self->current_start_offset = 0;
802 self->last_stop = GST_CLOCK_TIME_NONE;
805 case GST_STATE_CHANGE_PAUSED_TO_READY:{
806 GstIterator *iter = gst_element_iterate_sink_pads (element);
807 GstIteratorResult res;
809 g_mutex_lock (&self->lock);
811 res = gst_iterator_foreach (iter, unblock_pad, NULL);
812 } while (res == GST_ITERATOR_RESYNC);
814 gst_iterator_free (iter);
815 g_cond_broadcast (&self->cond);
816 g_mutex_unlock (&self->lock);
818 if (res == GST_ITERATOR_ERROR)
819 return GST_STATE_CHANGE_FAILURE;
827 ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
828 if (ret == GST_STATE_CHANGE_FAILURE)
831 switch (transition) {
832 case GST_STATE_CHANGE_PAUSED_TO_READY:{
833 GstIterator *iter = gst_element_iterate_sink_pads (element);
834 GstIteratorResult res;
837 res = gst_iterator_foreach (iter, reset_pad, NULL);
838 } while (res == GST_ITERATOR_RESYNC);
840 gst_iterator_free (iter);
842 if (res == GST_ITERATOR_ERROR)
843 return GST_STATE_CHANGE_FAILURE;