1 /* GStreamer output selector
2 * Copyright (C) 2008 Nokia Corporation. (contact <stefan.kost@nokia.com>)
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
14 * You should have received a copy of the GNU Library General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
17 * Boston, MA 02110-1301, USA.
21 * SECTION:element-output-selector
22 * @title: output-selector
23 * @see_also: #GstOutputSelector, #GstInputSelector
25 * Direct input stream to one out of N output pads.
34 #include "gstoutputselector.h"
36 GST_DEBUG_CATEGORY_STATIC (output_selector_debug);
37 #define GST_CAT_DEFAULT output_selector_debug
39 static GstStaticPadTemplate gst_output_selector_sink_factory =
40 GST_STATIC_PAD_TEMPLATE ("sink",
45 static GstStaticPadTemplate gst_output_selector_src_factory =
46 GST_STATIC_PAD_TEMPLATE ("src_%u",
51 #define GST_TYPE_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE (gst_output_selector_pad_negotiation_mode_get_type())
53 gst_output_selector_pad_negotiation_mode_get_type (void)
55 static GType pad_negotiation_mode_type = 0;
56 static const GEnumValue pad_negotiation_modes[] = {
57 {GST_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE_NONE, "None", "none"},
58 {GST_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE_ALL, "All", "all"},
59 {GST_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE_ACTIVE, "Active", "active"},
63 if (!pad_negotiation_mode_type) {
64 pad_negotiation_mode_type =
65 g_enum_register_static ("GstOutputSelectorPadNegotiationMode",
66 pad_negotiation_modes);
68 return pad_negotiation_mode_type;
77 PROP_PAD_NEGOTIATION_MODE
80 #define DEFAULT_PAD_NEGOTIATION_MODE GST_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE_ALL
83 GST_DEBUG_CATEGORY_INIT (output_selector_debug, \
84 "output-selector", 0, "Output stream selector");
85 #define gst_output_selector_parent_class parent_class
86 G_DEFINE_TYPE_WITH_CODE (GstOutputSelector, gst_output_selector,
87 GST_TYPE_ELEMENT, _do_init);
89 static void gst_output_selector_dispose (GObject * object);
90 static void gst_output_selector_set_property (GObject * object,
91 guint prop_id, const GValue * value, GParamSpec * pspec);
92 static void gst_output_selector_get_property (GObject * object,
93 guint prop_id, GValue * value, GParamSpec * pspec);
94 static GstPad *gst_output_selector_request_new_pad (GstElement * element,
95 GstPadTemplate * templ, const gchar * unused, const GstCaps * caps);
96 static void gst_output_selector_release_pad (GstElement * element,
98 static GstFlowReturn gst_output_selector_chain (GstPad * pad,
99 GstObject * parent, GstBuffer * buf);
100 static GstStateChangeReturn gst_output_selector_change_state (GstElement *
101 element, GstStateChange transition);
102 static gboolean gst_output_selector_event (GstPad * pad, GstObject * parent,
104 static gboolean gst_output_selector_query (GstPad * pad, GstObject * parent,
106 static void gst_output_selector_switch_pad_negotiation_mode (GstOutputSelector *
110 gst_output_selector_class_init (GstOutputSelectorClass * klass)
112 GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
113 GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
115 gobject_class->dispose = gst_output_selector_dispose;
117 gobject_class->set_property = gst_output_selector_set_property;
118 gobject_class->get_property = gst_output_selector_get_property;
120 g_object_class_install_property (gobject_class, PROP_ACTIVE_PAD,
121 g_param_spec_object ("active-pad", "Active pad",
122 "Currently active src pad", GST_TYPE_PAD,
123 G_PARAM_READWRITE | GST_PARAM_MUTABLE_PLAYING |
124 G_PARAM_STATIC_STRINGS));
125 g_object_class_install_property (gobject_class, PROP_RESEND_LATEST,
126 g_param_spec_boolean ("resend-latest", "Resend latest buffer",
127 "Resend latest buffer after a switch to a new pad", FALSE,
128 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
129 g_object_class_install_property (gobject_class, PROP_PAD_NEGOTIATION_MODE,
130 g_param_spec_enum ("pad-negotiation-mode", "Pad negotiation mode",
131 "The mode to be used for pad negotiation",
132 GST_TYPE_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE,
133 DEFAULT_PAD_NEGOTIATION_MODE,
134 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
136 gst_element_class_set_static_metadata (gstelement_class, "Output selector",
137 "Generic", "1-to-N output stream selector",
138 "Stefan Kost <stefan.kost@nokia.com>");
139 gst_element_class_add_static_pad_template (gstelement_class,
140 &gst_output_selector_sink_factory);
141 gst_element_class_add_static_pad_template (gstelement_class,
142 &gst_output_selector_src_factory);
144 gstelement_class->request_new_pad =
145 GST_DEBUG_FUNCPTR (gst_output_selector_request_new_pad);
146 gstelement_class->release_pad =
147 GST_DEBUG_FUNCPTR (gst_output_selector_release_pad);
149 gstelement_class->change_state = gst_output_selector_change_state;
153 gst_output_selector_init (GstOutputSelector * sel)
156 gst_pad_new_from_static_template (&gst_output_selector_sink_factory,
158 gst_pad_set_chain_function (sel->sinkpad,
159 GST_DEBUG_FUNCPTR (gst_output_selector_chain));
160 gst_pad_set_event_function (sel->sinkpad,
161 GST_DEBUG_FUNCPTR (gst_output_selector_event));
162 gst_pad_set_query_function (sel->sinkpad,
163 GST_DEBUG_FUNCPTR (gst_output_selector_query));
165 gst_element_add_pad (GST_ELEMENT (sel), sel->sinkpad);
167 /* srcpad management */
168 sel->active_srcpad = NULL;
170 gst_segment_init (&sel->segment, GST_FORMAT_UNDEFINED);
171 sel->pending_srcpad = NULL;
173 sel->resend_latest = FALSE;
174 sel->latest_buffer = NULL;
175 gst_output_selector_switch_pad_negotiation_mode (sel,
176 DEFAULT_PAD_NEGOTIATION_MODE);
180 gst_output_selector_reset (GstOutputSelector * osel)
182 GST_OBJECT_LOCK (osel);
183 if (osel->pending_srcpad != NULL) {
184 gst_object_unref (osel->pending_srcpad);
185 osel->pending_srcpad = NULL;
188 if (osel->latest_buffer != NULL) {
189 gst_buffer_unref (osel->latest_buffer);
190 osel->latest_buffer = NULL;
192 GST_OBJECT_UNLOCK (osel);
193 gst_segment_init (&osel->segment, GST_FORMAT_UNDEFINED);
197 gst_output_selector_dispose (GObject * object)
199 GstOutputSelector *osel = GST_OUTPUT_SELECTOR (object);
201 gst_output_selector_reset (osel);
203 G_OBJECT_CLASS (parent_class)->dispose (object);
207 gst_output_selector_set_property (GObject * object, guint prop_id,
208 const GValue * value, GParamSpec * pspec)
210 GstOutputSelector *sel = GST_OUTPUT_SELECTOR (object);
213 case PROP_ACTIVE_PAD:
217 next_pad = g_value_get_object (value);
219 GST_INFO_OBJECT (sel, "Activating pad %s:%s",
220 GST_DEBUG_PAD_NAME (next_pad));
222 /* guard against users setting a sink pad or foreign pad as active pad */
223 if (next_pad != NULL) {
224 g_return_if_fail (GST_PAD_IS_SRC (next_pad));
225 g_return_if_fail (GST_PAD_PARENT (next_pad) == GST_ELEMENT_CAST (sel));
228 GST_OBJECT_LOCK (object);
229 if (next_pad != sel->active_srcpad) {
230 /* switch to new srcpad in next chain run */
231 if (sel->pending_srcpad != NULL) {
232 GST_INFO ("replacing pending switch");
233 gst_object_unref (sel->pending_srcpad);
236 gst_object_ref (next_pad);
237 sel->pending_srcpad = next_pad;
239 GST_INFO ("pad already active");
240 if (sel->pending_srcpad != NULL) {
241 gst_object_unref (sel->pending_srcpad);
242 sel->pending_srcpad = NULL;
245 GST_OBJECT_UNLOCK (object);
248 case PROP_RESEND_LATEST:{
249 sel->resend_latest = g_value_get_boolean (value);
252 case PROP_PAD_NEGOTIATION_MODE:{
253 gst_output_selector_switch_pad_negotiation_mode (sel,
254 g_value_get_enum (value));
258 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
264 gst_output_selector_get_property (GObject * object, guint prop_id,
265 GValue * value, GParamSpec * pspec)
267 GstOutputSelector *sel = GST_OUTPUT_SELECTOR (object);
270 case PROP_ACTIVE_PAD:
271 GST_OBJECT_LOCK (object);
272 g_value_set_object (value,
273 sel->pending_srcpad ? sel->pending_srcpad : sel->active_srcpad);
274 GST_OBJECT_UNLOCK (object);
276 case PROP_RESEND_LATEST:{
277 GST_OBJECT_LOCK (object);
278 g_value_set_boolean (value, sel->resend_latest);
279 GST_OBJECT_UNLOCK (object);
282 case PROP_PAD_NEGOTIATION_MODE:
283 g_value_set_enum (value, sel->pad_negotiation_mode);
286 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
292 gst_output_selector_get_active (GstOutputSelector * sel)
294 GstPad *active = NULL;
296 GST_OBJECT_LOCK (sel);
297 if (sel->pending_srcpad)
298 active = gst_object_ref (sel->pending_srcpad);
299 else if (sel->active_srcpad)
300 active = gst_object_ref (sel->active_srcpad);
301 GST_OBJECT_UNLOCK (sel);
307 gst_output_selector_switch_pad_negotiation_mode (GstOutputSelector * sel,
310 sel->pad_negotiation_mode = mode;
314 forward_sticky_events (GstPad * pad, GstEvent ** event, gpointer user_data)
316 GstPad *srcpad = GST_PAD_CAST (user_data);
318 gst_pad_push_event (srcpad, gst_event_ref (*event));
324 gst_output_selector_request_new_pad (GstElement * element,
325 GstPadTemplate * templ, const gchar * name, const GstCaps * caps)
329 GstOutputSelector *osel;
331 osel = GST_OUTPUT_SELECTOR (element);
333 GST_DEBUG_OBJECT (osel, "requesting pad");
335 GST_OBJECT_LOCK (osel);
336 padname = g_strdup_printf ("src_%u", osel->nb_srcpads++);
337 srcpad = gst_pad_new_from_template (templ, padname);
338 GST_OBJECT_UNLOCK (osel);
340 gst_pad_set_active (srcpad, TRUE);
342 /* Forward sticky events to the new srcpad */
343 gst_pad_sticky_events_foreach (osel->sinkpad, forward_sticky_events, srcpad);
345 gst_element_add_pad (GST_ELEMENT (osel), srcpad);
347 /* Set the first requested src pad as active by default */
348 GST_OBJECT_LOCK (osel);
349 if (osel->active_srcpad == NULL) {
350 osel->active_srcpad = srcpad;
351 GST_OBJECT_UNLOCK (osel);
352 g_object_notify (G_OBJECT (osel), "active-pad");
354 GST_OBJECT_UNLOCK (osel);
362 gst_output_selector_release_pad (GstElement * element, GstPad * pad)
364 GstOutputSelector *osel;
366 osel = GST_OUTPUT_SELECTOR (element);
368 GST_DEBUG_OBJECT (osel, "releasing pad");
370 /* Disable active pad if it's the to be removed pad */
371 GST_OBJECT_LOCK (osel);
372 if (osel->active_srcpad == pad) {
373 osel->active_srcpad = NULL;
374 GST_OBJECT_UNLOCK (osel);
375 g_object_notify (G_OBJECT (osel), "active-pad");
377 GST_OBJECT_UNLOCK (osel);
380 gst_pad_set_active (pad, FALSE);
382 gst_element_remove_pad (GST_ELEMENT_CAST (osel), pad);
386 gst_output_selector_switch (GstOutputSelector * osel)
388 gboolean res = FALSE;
390 GstSegment *seg = NULL;
391 GstPad *active_srcpad;
394 GST_OBJECT_LOCK (osel);
395 GST_INFO_OBJECT (osel, "switching to pad %" GST_PTR_FORMAT,
396 osel->pending_srcpad);
397 if (!osel->pending_srcpad) {
398 GST_OBJECT_UNLOCK (osel);
402 if (gst_pad_is_linked (osel->pending_srcpad)) {
403 osel->active_srcpad = osel->pending_srcpad;
406 gst_object_unref (osel->pending_srcpad);
407 osel->pending_srcpad = NULL;
408 active_srcpad = res ? gst_object_ref (osel->active_srcpad) : NULL;
409 GST_OBJECT_UNLOCK (osel);
411 /* Send SEGMENT event and latest buffer if switching succeeded
412 * and we already have a valid segment configured */
414 GstBuffer *latest_buffer;
416 g_object_notify (G_OBJECT (osel), "active-pad");
418 GST_OBJECT_LOCK (osel);
420 osel->latest_buffer ? gst_buffer_ref (osel->latest_buffer) : NULL;
421 GST_OBJECT_UNLOCK (osel);
423 gst_pad_sticky_events_foreach (osel->sinkpad, forward_sticky_events,
426 /* update segment if required */
427 if (osel->segment.format != GST_FORMAT_UNDEFINED) {
428 /* Send SEGMENT to the pad we are going to switch to */
429 seg = &osel->segment;
430 /* If resending then mark segment start and position accordingly */
431 if (osel->resend_latest && latest_buffer &&
432 GST_BUFFER_TIMESTAMP_IS_VALID (latest_buffer)) {
433 seg->position = GST_BUFFER_TIMESTAMP (latest_buffer);
436 ev = gst_event_new_segment (seg);
438 if (!gst_pad_push_event (active_srcpad, ev)) {
439 GST_WARNING_OBJECT (osel,
440 "newsegment handling failed in %" GST_PTR_FORMAT, active_srcpad);
444 /* Resend latest buffer to newly switched pad */
445 if (osel->resend_latest && latest_buffer) {
446 GST_INFO ("resending latest buffer");
447 gst_pad_push (active_srcpad, latest_buffer);
448 } else if (latest_buffer) {
449 gst_buffer_unref (latest_buffer);
452 gst_object_unref (active_srcpad);
454 GST_WARNING_OBJECT (osel, "switch failed, pad not linked");
461 gst_output_selector_chain (GstPad * pad, GstObject * parent, GstBuffer * buf)
464 GstOutputSelector *osel;
465 GstClockTime position, duration;
466 GstPad *active_srcpad;
468 osel = GST_OUTPUT_SELECTOR (parent);
471 * The _switch function might push a buffer if 'resend-latest' is true.
473 * Elements/Applications (e.g. camerabin) might use pad probes to
474 * switch output-selector's active pad. If we simply switch and don't
475 * recheck any pending pad switch the following codepath could end
476 * up pushing a buffer on a non-active pad. This is bad.
478 * So we always should check the pending_srcpad before going further down
479 * the chain and pushing the new buffer
481 while (osel->pending_srcpad) {
483 gst_output_selector_switch (osel);
486 active_srcpad = gst_output_selector_get_active (osel);
487 if (!active_srcpad) {
488 GST_DEBUG_OBJECT (osel, "No active srcpad");
489 gst_buffer_unref (buf);
493 GST_OBJECT_LOCK (osel);
494 if (osel->latest_buffer) {
495 gst_buffer_unref (osel->latest_buffer);
496 osel->latest_buffer = NULL;
499 if (osel->resend_latest) {
500 /* Keep reference to latest buffer to resend it after switch */
501 osel->latest_buffer = gst_buffer_ref (buf);
503 GST_OBJECT_UNLOCK (osel);
505 /* Keep track of last stop and use it in SEGMENT start after
506 switching to a new src pad */
507 position = GST_BUFFER_TIMESTAMP (buf);
508 if (GST_CLOCK_TIME_IS_VALID (position)) {
509 duration = GST_BUFFER_DURATION (buf);
510 if (GST_CLOCK_TIME_IS_VALID (duration)) {
511 position += duration;
513 GST_LOG_OBJECT (osel, "setting last stop %" GST_TIME_FORMAT,
514 GST_TIME_ARGS (position));
515 osel->segment.position = position;
518 GST_LOG_OBJECT (osel, "pushing buffer to %" GST_PTR_FORMAT, active_srcpad);
519 res = gst_pad_push (active_srcpad, buf);
521 gst_object_unref (active_srcpad);
526 static GstStateChangeReturn
527 gst_output_selector_change_state (GstElement * element,
528 GstStateChange transition)
530 GstOutputSelector *sel;
531 GstStateChangeReturn result;
533 sel = GST_OUTPUT_SELECTOR (element);
535 switch (transition) {
536 case GST_STATE_CHANGE_READY_TO_PAUSED:
542 result = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
544 switch (transition) {
545 case GST_STATE_CHANGE_PAUSED_TO_READY:
546 gst_output_selector_reset (sel);
556 gst_output_selector_forward_event (GstOutputSelector * sel, GstEvent * event)
561 switch (sel->pad_negotiation_mode) {
562 case GST_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE_ALL:
563 /* Send to all src pads */
564 res = gst_pad_event_default (sel->sinkpad, GST_OBJECT_CAST (sel), event);
566 case GST_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE_NONE:
567 gst_event_unref (event);
570 active = gst_output_selector_get_active (sel);
572 res = gst_pad_push_event (active, event);
573 gst_object_unref (active);
575 gst_event_unref (event);
584 gst_output_selector_event (GstPad * pad, GstObject * parent, GstEvent * event)
587 GstOutputSelector *sel;
588 GstPad *active = NULL;
590 sel = GST_OUTPUT_SELECTOR (parent);
592 switch (GST_EVENT_TYPE (event)) {
595 res = gst_output_selector_forward_event (sel, event);
598 case GST_EVENT_SEGMENT:
600 gst_event_copy_segment (event, &sel->segment);
601 GST_DEBUG_OBJECT (sel, "configured SEGMENT %" GST_SEGMENT_FORMAT,
607 active = gst_output_selector_get_active (sel);
609 res = gst_pad_push_event (active, event);
610 gst_object_unref (active);
612 gst_event_unref (event);
622 gst_output_selector_query (GstPad * pad, GstObject * parent, GstQuery * query)
625 GstOutputSelector *sel;
626 GstPad *active = NULL;
628 sel = GST_OUTPUT_SELECTOR (parent);
630 switch (GST_QUERY_TYPE (query)) {
633 switch (sel->pad_negotiation_mode) {
634 case GST_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE_ALL:
635 /* Send caps to all src pads */
636 res = gst_pad_proxy_query_caps (pad, query);
638 case GST_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE_NONE:
642 active = gst_output_selector_get_active (sel);
644 res = gst_pad_peer_query (active, query);
645 gst_object_unref (active);
653 case GST_QUERY_DRAIN:
654 if (sel->latest_buffer) {
655 gst_buffer_unref (sel->latest_buffer);
656 sel->latest_buffer = NULL;
660 res = gst_pad_query_default (pad, parent, query);