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 * @see_also: #GstOutputSelector, #GstInputSelector
24 * Direct input stream to one out of N output pads.
33 #include "gstoutputselector.h"
35 GST_DEBUG_CATEGORY_STATIC (output_selector_debug);
36 #define GST_CAT_DEFAULT output_selector_debug
38 static GstStaticPadTemplate gst_output_selector_sink_factory =
39 GST_STATIC_PAD_TEMPLATE ("sink",
44 static GstStaticPadTemplate gst_output_selector_src_factory =
45 GST_STATIC_PAD_TEMPLATE ("src_%u",
50 #define GST_TYPE_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE (gst_output_selector_pad_negotiation_mode_get_type())
52 gst_output_selector_pad_negotiation_mode_get_type (void)
54 static GType pad_negotiation_mode_type = 0;
55 static GEnumValue pad_negotiation_modes[] = {
56 {GST_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE_NONE, "None", "none"},
57 {GST_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE_ALL, "All", "all"},
58 {GST_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE_ACTIVE, "Active", "active"},
62 if (!pad_negotiation_mode_type) {
63 pad_negotiation_mode_type =
64 g_enum_register_static ("GstOutputSelectorPadNegotiationMode",
65 pad_negotiation_modes);
67 return pad_negotiation_mode_type;
76 PROP_PAD_NEGOTIATION_MODE
79 #define DEFAULT_PAD_NEGOTIATION_MODE GST_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE_ALL
82 GST_DEBUG_CATEGORY_INIT (output_selector_debug, \
83 "output-selector", 0, "Output stream selector");
84 #define gst_output_selector_parent_class parent_class
85 G_DEFINE_TYPE_WITH_CODE (GstOutputSelector, gst_output_selector,
86 GST_TYPE_ELEMENT, _do_init);
88 static void gst_output_selector_dispose (GObject * object);
89 static void gst_output_selector_set_property (GObject * object,
90 guint prop_id, const GValue * value, GParamSpec * pspec);
91 static void gst_output_selector_get_property (GObject * object,
92 guint prop_id, GValue * value, GParamSpec * pspec);
93 static GstPad *gst_output_selector_request_new_pad (GstElement * element,
94 GstPadTemplate * templ, const gchar * unused, const GstCaps * caps);
95 static void gst_output_selector_release_pad (GstElement * element,
97 static GstFlowReturn gst_output_selector_chain (GstPad * pad,
98 GstObject * parent, GstBuffer * buf);
99 static GstStateChangeReturn gst_output_selector_change_state (GstElement *
100 element, GstStateChange transition);
101 static gboolean gst_output_selector_event (GstPad * pad, GstObject * parent,
103 static gboolean gst_output_selector_query (GstPad * pad, GstObject * parent,
105 static void gst_output_selector_switch_pad_negotiation_mode (GstOutputSelector *
109 gst_output_selector_class_init (GstOutputSelectorClass * klass)
111 GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
112 GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
114 gobject_class->dispose = gst_output_selector_dispose;
116 gobject_class->set_property = gst_output_selector_set_property;
117 gobject_class->get_property = gst_output_selector_get_property;
119 g_object_class_install_property (gobject_class, PROP_ACTIVE_PAD,
120 g_param_spec_object ("active-pad", "Active pad",
121 "Currently active src pad", GST_TYPE_PAD,
122 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
123 g_object_class_install_property (gobject_class, PROP_RESEND_LATEST,
124 g_param_spec_boolean ("resend-latest", "Resend latest buffer",
125 "Resend latest buffer after a switch to a new pad", FALSE,
126 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
127 g_object_class_install_property (gobject_class, PROP_PAD_NEGOTIATION_MODE,
128 g_param_spec_enum ("pad-negotiation-mode", "Pad negotiation mode",
129 "The mode to be used for pad negotiation",
130 GST_TYPE_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE,
131 DEFAULT_PAD_NEGOTIATION_MODE,
132 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
134 gst_element_class_set_static_metadata (gstelement_class, "Output selector",
135 "Generic", "1-to-N output stream selector",
136 "Stefan Kost <stefan.kost@nokia.com>");
137 gst_element_class_add_pad_template (gstelement_class,
138 gst_static_pad_template_get (&gst_output_selector_sink_factory));
139 gst_element_class_add_pad_template (gstelement_class,
140 gst_static_pad_template_get (&gst_output_selector_src_factory));
142 gstelement_class->request_new_pad =
143 GST_DEBUG_FUNCPTR (gst_output_selector_request_new_pad);
144 gstelement_class->release_pad =
145 GST_DEBUG_FUNCPTR (gst_output_selector_release_pad);
147 gstelement_class->change_state = gst_output_selector_change_state;
151 gst_output_selector_init (GstOutputSelector * sel)
154 gst_pad_new_from_static_template (&gst_output_selector_sink_factory,
156 gst_pad_set_chain_function (sel->sinkpad,
157 GST_DEBUG_FUNCPTR (gst_output_selector_chain));
158 gst_pad_set_event_function (sel->sinkpad,
159 GST_DEBUG_FUNCPTR (gst_output_selector_event));
160 gst_pad_set_query_function (sel->sinkpad,
161 GST_DEBUG_FUNCPTR (gst_output_selector_query));
163 gst_element_add_pad (GST_ELEMENT (sel), sel->sinkpad);
165 /* srcpad management */
166 sel->active_srcpad = NULL;
168 gst_segment_init (&sel->segment, GST_FORMAT_UNDEFINED);
169 sel->pending_srcpad = NULL;
171 sel->resend_latest = FALSE;
172 sel->latest_buffer = NULL;
173 gst_output_selector_switch_pad_negotiation_mode (sel,
174 DEFAULT_PAD_NEGOTIATION_MODE);
178 gst_output_selector_reset (GstOutputSelector * osel)
180 if (osel->pending_srcpad != NULL) {
181 gst_object_unref (osel->pending_srcpad);
182 osel->pending_srcpad = NULL;
184 if (osel->latest_buffer != NULL) {
185 gst_buffer_unref (osel->latest_buffer);
186 osel->latest_buffer = NULL;
188 gst_segment_init (&osel->segment, GST_FORMAT_UNDEFINED);
192 gst_output_selector_dispose (GObject * object)
194 GstOutputSelector *osel = GST_OUTPUT_SELECTOR (object);
196 gst_output_selector_reset (osel);
198 G_OBJECT_CLASS (parent_class)->dispose (object);
202 gst_output_selector_set_property (GObject * object, guint prop_id,
203 const GValue * value, GParamSpec * pspec)
205 GstOutputSelector *sel = GST_OUTPUT_SELECTOR (object);
208 case PROP_ACTIVE_PAD:
212 next_pad = g_value_get_object (value);
214 GST_INFO_OBJECT (sel, "Activating pad %s:%s",
215 GST_DEBUG_PAD_NAME (next_pad));
217 GST_OBJECT_LOCK (object);
218 if (next_pad != sel->active_srcpad) {
219 /* switch to new srcpad in next chain run */
220 if (sel->pending_srcpad != NULL) {
221 GST_INFO ("replacing pending switch");
222 gst_object_unref (sel->pending_srcpad);
225 gst_object_ref (next_pad);
226 sel->pending_srcpad = next_pad;
228 GST_INFO ("pad already active");
229 if (sel->pending_srcpad != NULL) {
230 gst_object_unref (sel->pending_srcpad);
231 sel->pending_srcpad = NULL;
234 GST_OBJECT_UNLOCK (object);
237 case PROP_RESEND_LATEST:{
238 sel->resend_latest = g_value_get_boolean (value);
241 case PROP_PAD_NEGOTIATION_MODE:{
242 gst_output_selector_switch_pad_negotiation_mode (sel,
243 g_value_get_enum (value));
247 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
253 gst_output_selector_get_property (GObject * object, guint prop_id,
254 GValue * value, GParamSpec * pspec)
256 GstOutputSelector *sel = GST_OUTPUT_SELECTOR (object);
259 case PROP_ACTIVE_PAD:
260 GST_OBJECT_LOCK (object);
261 g_value_set_object (value,
262 sel->pending_srcpad ? sel->pending_srcpad : sel->active_srcpad);
263 GST_OBJECT_UNLOCK (object);
265 case PROP_RESEND_LATEST:{
266 GST_OBJECT_LOCK (object);
267 g_value_set_boolean (value, sel->resend_latest);
268 GST_OBJECT_UNLOCK (object);
271 case PROP_PAD_NEGOTIATION_MODE:
272 g_value_set_enum (value, sel->pad_negotiation_mode);
275 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
281 gst_output_selector_get_active (GstOutputSelector * sel)
283 GstPad *active = NULL;
285 GST_OBJECT_LOCK (sel);
286 if (sel->pending_srcpad)
287 active = gst_object_ref (sel->pending_srcpad);
288 else if (sel->active_srcpad)
289 active = gst_object_ref (sel->active_srcpad);
290 GST_OBJECT_UNLOCK (sel);
296 gst_output_selector_switch_pad_negotiation_mode (GstOutputSelector * sel,
299 sel->pad_negotiation_mode = mode;
303 forward_sticky_events (GstPad * pad, GstEvent ** event, gpointer user_data)
305 GstPad *srcpad = GST_PAD_CAST (user_data);
307 gst_pad_push_event (srcpad, gst_event_ref (*event));
313 gst_output_selector_request_new_pad (GstElement * element,
314 GstPadTemplate * templ, const gchar * name, const GstCaps * caps)
318 GstOutputSelector *osel;
320 osel = GST_OUTPUT_SELECTOR (element);
322 GST_DEBUG_OBJECT (osel, "requesting pad");
324 GST_OBJECT_LOCK (osel);
325 padname = g_strdup_printf ("src_%u", osel->nb_srcpads++);
326 srcpad = gst_pad_new_from_template (templ, padname);
327 GST_OBJECT_UNLOCK (osel);
329 gst_pad_set_active (srcpad, TRUE);
331 /* Forward sticky events to the new srcpad */
332 gst_pad_sticky_events_foreach (osel->sinkpad, forward_sticky_events, srcpad);
334 gst_element_add_pad (GST_ELEMENT (osel), srcpad);
336 /* Set the first requested src pad as active by default */
337 if (osel->active_srcpad == NULL) {
338 osel->active_srcpad = srcpad;
346 gst_output_selector_release_pad (GstElement * element, GstPad * pad)
348 GstOutputSelector *osel;
350 osel = GST_OUTPUT_SELECTOR (element);
352 GST_DEBUG_OBJECT (osel, "releasing pad");
354 gst_pad_set_active (pad, FALSE);
356 gst_element_remove_pad (GST_ELEMENT_CAST (osel), pad);
360 gst_output_selector_switch (GstOutputSelector * osel)
362 gboolean res = FALSE;
364 GstSegment *seg = NULL;
367 GST_OBJECT_LOCK (GST_OBJECT (osel));
368 GST_INFO_OBJECT (osel, "switching to pad %" GST_PTR_FORMAT,
369 osel->pending_srcpad);
370 if (gst_pad_is_linked (osel->pending_srcpad)) {
371 osel->active_srcpad = osel->pending_srcpad;
374 gst_object_unref (osel->pending_srcpad);
375 osel->pending_srcpad = NULL;
376 GST_OBJECT_UNLOCK (GST_OBJECT (osel));
378 /* Send SEGMENT event and latest buffer if switching succeeded
379 * and we already have a valid segment configured */
381 gst_pad_sticky_events_foreach (osel->sinkpad, forward_sticky_events,
382 osel->active_srcpad);
384 /* update segment if required */
385 if (osel->segment.format != GST_FORMAT_UNDEFINED) {
386 /* Send SEGMENT to the pad we are going to switch to */
387 seg = &osel->segment;
388 /* If resending then mark segment start and position accordingly */
389 if (osel->resend_latest && osel->latest_buffer &&
390 GST_BUFFER_TIMESTAMP_IS_VALID (osel->latest_buffer)) {
391 seg->position = GST_BUFFER_TIMESTAMP (osel->latest_buffer);
394 ev = gst_event_new_segment (seg);
396 if (!gst_pad_push_event (osel->active_srcpad, ev)) {
397 GST_WARNING_OBJECT (osel,
398 "newsegment handling failed in %" GST_PTR_FORMAT,
399 osel->active_srcpad);
403 /* Resend latest buffer to newly switched pad */
404 if (osel->resend_latest && osel->latest_buffer) {
405 GST_INFO ("resending latest buffer");
406 gst_pad_push (osel->active_srcpad, gst_buffer_ref (osel->latest_buffer));
409 GST_WARNING_OBJECT (osel, "switch failed, pad not linked");
416 gst_output_selector_chain (GstPad * pad, GstObject * parent, GstBuffer * buf)
419 GstOutputSelector *osel;
420 GstClockTime position, duration;
422 osel = GST_OUTPUT_SELECTOR (parent);
425 * The _switch function might push a buffer if 'resend-latest' is true.
427 * Elements/Applications (e.g. camerabin) might use pad probes to
428 * switch output-selector's active pad. If we simply switch and don't
429 * recheck any pending pad switch the following codepath could end
430 * up pushing a buffer on a non-active pad. This is bad.
432 * So we always should check the pending_srcpad before going further down
433 * the chain and pushing the new buffer
435 while (osel->pending_srcpad) {
437 gst_output_selector_switch (osel);
440 if (osel->latest_buffer) {
441 gst_buffer_unref (osel->latest_buffer);
442 osel->latest_buffer = NULL;
445 if (osel->resend_latest) {
446 /* Keep reference to latest buffer to resend it after switch */
447 osel->latest_buffer = gst_buffer_ref (buf);
450 /* Keep track of last stop and use it in SEGMENT start after
451 switching to a new src pad */
452 position = GST_BUFFER_TIMESTAMP (buf);
453 if (GST_CLOCK_TIME_IS_VALID (position)) {
454 duration = GST_BUFFER_DURATION (buf);
455 if (GST_CLOCK_TIME_IS_VALID (duration)) {
456 position += duration;
458 GST_LOG_OBJECT (osel, "setting last stop %" GST_TIME_FORMAT,
459 GST_TIME_ARGS (position));
460 osel->segment.position = position;
463 GST_LOG_OBJECT (osel, "pushing buffer to %" GST_PTR_FORMAT,
464 osel->active_srcpad);
465 res = gst_pad_push (osel->active_srcpad, buf);
470 static GstStateChangeReturn
471 gst_output_selector_change_state (GstElement * element,
472 GstStateChange transition)
474 GstOutputSelector *sel;
475 GstStateChangeReturn result;
477 sel = GST_OUTPUT_SELECTOR (element);
479 switch (transition) {
480 case GST_STATE_CHANGE_READY_TO_PAUSED:
486 result = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
488 switch (transition) {
489 case GST_STATE_CHANGE_PAUSED_TO_READY:
490 gst_output_selector_reset (sel);
500 gst_output_selector_forward_event (GstOutputSelector * sel, GstEvent * event)
505 switch (sel->pad_negotiation_mode) {
506 case GST_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE_ALL:
507 /* Send to all src pads */
508 res = gst_pad_event_default (sel->sinkpad, GST_OBJECT_CAST (sel), event);
510 case GST_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE_NONE:
511 gst_event_unref (event);
514 active = gst_output_selector_get_active (sel);
516 res = gst_pad_push_event (active, event);
517 gst_object_unref (active);
519 gst_event_unref (event);
528 gst_output_selector_event (GstPad * pad, GstObject * parent, GstEvent * event)
531 GstOutputSelector *sel;
532 GstPad *active = NULL;
534 sel = GST_OUTPUT_SELECTOR (parent);
536 switch (GST_EVENT_TYPE (event)) {
537 case GST_EVENT_SEGMENT:
539 gst_event_copy_segment (event, &sel->segment);
541 GST_DEBUG_OBJECT (sel, "configured SEGMENT %" GST_SEGMENT_FORMAT,
544 res = gst_output_selector_forward_event (sel, event);
549 if (GST_EVENT_IS_STICKY (event)) {
550 res = gst_output_selector_forward_event (sel, event);
552 /* Send other events to pending or active src pad */
553 active = gst_output_selector_get_active (sel);
555 res = gst_pad_push_event (active, event);
556 gst_object_unref (active);
558 gst_event_unref (event);
569 gst_output_selector_query (GstPad * pad, GstObject * parent, GstQuery * query)
572 GstOutputSelector *sel;
573 GstPad *active = NULL;
575 sel = GST_OUTPUT_SELECTOR (parent);
577 switch (GST_QUERY_TYPE (query)) {
580 switch (sel->pad_negotiation_mode) {
581 case GST_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE_ALL:
582 /* Send caps to all src pads */
583 res = gst_pad_proxy_query_caps (pad, query);
585 case GST_OUTPUT_SELECTOR_PAD_NEGOTIATION_MODE_NONE:
589 active = gst_output_selector_get_active (sel);
591 res = gst_pad_peer_query (active, query);
592 gst_object_unref (active);
601 res = gst_pad_query_default (pad, parent, query);