4 * Copyright (C) 2005 Nokia Corporation.
5 * @author Kai Vehmanen <kai.vehmanen@nokia.com>
7 * Loosely based on GStreamer gstdecodebin
8 * Copyright (C) <2004> Wim Taymans <wim.taymans@gmail.com>
10 * This library is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU Library General Public
12 * License as published by the Free Software Foundation; either
13 * version 2 of the License, or (at your option) any later version.
15 * This library is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * Library General Public License for more details.
20 * You should have received a copy of the GNU Library General Public
21 * License along with this library; if not, write to the
22 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
23 * Boston, MA 02110-1301, USA.
27 * SECTION:element-gstrtpptdemux
29 * gstrtpptdemux acts as a demuxer for RTP packets based on the payload type of
30 * the packets. Its main purpose is to allow an application to easily receive
31 * and decode an RTP stream with multiple payload types.
33 * For each payload type that is detected, a new pad will be created and the
34 * #GstRtpPtDemux::new-payload-type signal will be emitted. When the payload for
35 * the RTP stream changes, the #GstRtpPtDemux::payload-type-change signal will be
38 * The element will try to set complete and unique application/x-rtp caps on the
39 * outgoing buffers and pads based on the result of the
40 * #GstRtpPtDemux::request-pt-map signal.
43 * <title>Example pipelines</title>
45 * gst-launch-1.0 udpsrc caps="application/x-rtp" ! gstrtpptdemux ! fakesink
46 * ]| Takes an RTP stream and send the RTP packets with the first detected
47 * payload type to fakesink, discarding the other payload types.
50 * Last reviewed on 2007-05-28 (0.10.5)
55 * Andre Moreira Magalhaes <andre.magalhaes@indt.org.br>
59 * - works with the test_rtpdemux.c tool
62 * - is emitting a signal enough, or should we
63 * use GstEvent to notify downstream elements
64 * of the new packet... no?
67 * - emits event both for new PTs, and whenever
77 #include <gst/rtp/gstrtpbuffer.h>
79 #include "gstrtpptdemux.h"
81 /* generic templates */
82 static GstStaticPadTemplate rtp_pt_demux_sink_template =
83 GST_STATIC_PAD_TEMPLATE ("sink",
86 GST_STATIC_CAPS ("application/x-rtp")
89 static GstStaticPadTemplate rtp_pt_demux_src_template =
90 GST_STATIC_PAD_TEMPLATE ("src_%u",
93 GST_STATIC_CAPS ("application/x-rtp, " "payload = (int) [ 0, 255 ]")
96 GST_DEBUG_CATEGORY_STATIC (gst_rtp_pt_demux_debug);
97 #define GST_CAT_DEFAULT gst_rtp_pt_demux_debug
100 * Item for storing GstPad<->pt pairs.
102 struct _GstRtpPtDemuxPad
104 GstPad *pad; /**< pointer to the actual pad */
105 gint pt; /**< RTP payload-type attached to pad */
112 SIGNAL_REQUEST_PT_MAP,
113 SIGNAL_NEW_PAYLOAD_TYPE,
114 SIGNAL_PAYLOAD_TYPE_CHANGE,
119 #define gst_rtp_pt_demux_parent_class parent_class
120 G_DEFINE_TYPE (GstRtpPtDemux, gst_rtp_pt_demux, GST_TYPE_ELEMENT);
122 static void gst_rtp_pt_demux_finalize (GObject * object);
124 static void gst_rtp_pt_demux_release (GstRtpPtDemux * ptdemux);
125 static gboolean gst_rtp_pt_demux_setup (GstRtpPtDemux * ptdemux);
127 static gboolean gst_rtp_pt_demux_sink_event (GstPad * pad, GstObject * parent,
129 static GstFlowReturn gst_rtp_pt_demux_chain (GstPad * pad, GstObject * parent,
131 static GstStateChangeReturn gst_rtp_pt_demux_change_state (GstElement * element,
132 GstStateChange transition);
133 static void gst_rtp_pt_demux_clear_pt_map (GstRtpPtDemux * rtpdemux);
135 static GstPad *find_pad_for_pt (GstRtpPtDemux * rtpdemux, guint8 pt);
137 static gboolean gst_rtp_pt_demux_src_event (GstPad * pad, GstObject * parent,
141 static guint gst_rtp_pt_demux_signals[LAST_SIGNAL] = { 0 };
144 gst_rtp_pt_demux_class_init (GstRtpPtDemuxClass * klass)
146 GObjectClass *gobject_klass;
147 GstElementClass *gstelement_klass;
149 gobject_klass = (GObjectClass *) klass;
150 gstelement_klass = (GstElementClass *) klass;
153 * GstRtpPtDemux::request-pt-map:
154 * @demux: the object which received the signal
155 * @pt: the payload type
157 * Request the payload type as #GstCaps for @pt.
159 gst_rtp_pt_demux_signals[SIGNAL_REQUEST_PT_MAP] =
160 g_signal_new ("request-pt-map", G_TYPE_FROM_CLASS (klass),
161 G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstRtpPtDemuxClass, request_pt_map),
162 NULL, NULL, g_cclosure_marshal_generic, GST_TYPE_CAPS, 1, G_TYPE_UINT);
165 * GstRtpPtDemux::new-payload-type:
166 * @demux: the object which received the signal
167 * @pt: the payload type
168 * @pad: the pad with the new payload
170 * Emited when a new payload type pad has been created in @demux.
172 gst_rtp_pt_demux_signals[SIGNAL_NEW_PAYLOAD_TYPE] =
173 g_signal_new ("new-payload-type", G_TYPE_FROM_CLASS (klass),
174 G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstRtpPtDemuxClass, new_payload_type),
175 NULL, NULL, g_cclosure_marshal_generic, G_TYPE_NONE, 2, G_TYPE_UINT,
179 * GstRtpPtDemux::payload-type-change:
180 * @demux: the object which received the signal
181 * @pt: the new payload type
183 * Emited when the payload type changed.
185 gst_rtp_pt_demux_signals[SIGNAL_PAYLOAD_TYPE_CHANGE] =
186 g_signal_new ("payload-type-change", G_TYPE_FROM_CLASS (klass),
187 G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstRtpPtDemuxClass,
188 payload_type_change), NULL, NULL, g_cclosure_marshal_VOID__UINT,
189 G_TYPE_NONE, 1, G_TYPE_UINT);
192 * GstRtpPtDemux::clear-pt-map:
193 * @demux: the object which received the signal
195 * The application can call this signal to instruct the element to discard the
196 * currently cached payload type map.
198 gst_rtp_pt_demux_signals[SIGNAL_CLEAR_PT_MAP] =
199 g_signal_new ("clear-pt-map", G_TYPE_FROM_CLASS (klass),
200 G_SIGNAL_ACTION | G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstRtpPtDemuxClass,
201 clear_pt_map), NULL, NULL, g_cclosure_marshal_VOID__VOID,
202 G_TYPE_NONE, 0, G_TYPE_NONE);
204 gobject_klass->finalize = gst_rtp_pt_demux_finalize;
206 gstelement_klass->change_state =
207 GST_DEBUG_FUNCPTR (gst_rtp_pt_demux_change_state);
209 klass->clear_pt_map = GST_DEBUG_FUNCPTR (gst_rtp_pt_demux_clear_pt_map);
211 gst_element_class_add_pad_template (gstelement_klass,
212 gst_static_pad_template_get (&rtp_pt_demux_sink_template));
213 gst_element_class_add_pad_template (gstelement_klass,
214 gst_static_pad_template_get (&rtp_pt_demux_src_template));
216 gst_element_class_set_static_metadata (gstelement_klass, "RTP Demux",
218 "Parses codec streams transmitted in the same RTP session",
219 "Kai Vehmanen <kai.vehmanen@nokia.com>");
221 GST_DEBUG_CATEGORY_INIT (gst_rtp_pt_demux_debug,
222 "rtpptdemux", 0, "RTP codec demuxer");
226 gst_rtp_pt_demux_init (GstRtpPtDemux * ptdemux)
228 GstElementClass *klass = GST_ELEMENT_GET_CLASS (ptdemux);
231 gst_pad_new_from_template (gst_element_class_get_pad_template (klass,
233 g_assert (ptdemux->sink != NULL);
235 gst_pad_set_chain_function (ptdemux->sink, gst_rtp_pt_demux_chain);
236 gst_pad_set_event_function (ptdemux->sink, gst_rtp_pt_demux_sink_event);
238 gst_element_add_pad (GST_ELEMENT (ptdemux), ptdemux->sink);
242 gst_rtp_pt_demux_finalize (GObject * object)
244 gst_rtp_pt_demux_release (GST_RTP_PT_DEMUX (object));
246 G_OBJECT_CLASS (parent_class)->finalize (object);
250 gst_rtp_pt_demux_get_caps (GstRtpPtDemux * rtpdemux, guint pt)
254 GValue args[2] = { {0}, {0} };
256 /* figure out the caps */
257 g_value_init (&args[0], GST_TYPE_ELEMENT);
258 g_value_set_object (&args[0], rtpdemux);
259 g_value_init (&args[1], G_TYPE_UINT);
260 g_value_set_uint (&args[1], pt);
262 g_value_init (&ret, GST_TYPE_CAPS);
263 g_value_set_boxed (&ret, NULL);
265 g_signal_emitv (args, gst_rtp_pt_demux_signals[SIGNAL_REQUEST_PT_MAP], 0,
268 g_value_unset (&args[0]);
269 g_value_unset (&args[1]);
270 caps = g_value_dup_boxed (&ret);
271 g_value_unset (&ret);
273 caps = gst_pad_get_current_caps (rtpdemux->sink);
276 GST_DEBUG ("pt %d, got caps %" GST_PTR_FORMAT, pt, caps);
282 gst_rtp_pt_demux_clear_pt_map (GstRtpPtDemux * rtpdemux)
286 GST_OBJECT_LOCK (rtpdemux);
287 GST_DEBUG ("clearing pt map");
288 for (walk = rtpdemux->srcpads; walk; walk = g_slist_next (walk)) {
289 GstRtpPtDemuxPad *pad = walk->data;
293 GST_OBJECT_UNLOCK (rtpdemux);
297 need_caps_for_pt (GstRtpPtDemux * rtpdemux, guint8 pt)
300 gboolean ret = FALSE;
302 GST_OBJECT_LOCK (rtpdemux);
303 for (walk = rtpdemux->srcpads; walk; walk = g_slist_next (walk)) {
304 GstRtpPtDemuxPad *pad = walk->data;
310 GST_OBJECT_UNLOCK (rtpdemux);
317 clear_newcaps_for_pt (GstRtpPtDemux * rtpdemux, guint8 pt)
321 GST_OBJECT_LOCK (rtpdemux);
322 for (walk = rtpdemux->srcpads; walk; walk = g_slist_next (walk)) {
323 GstRtpPtDemuxPad *pad = walk->data;
326 pad->newcaps = FALSE;
330 GST_OBJECT_UNLOCK (rtpdemux);
334 forward_sticky_events (GstPad * pad, GstEvent ** event, gpointer user_data)
336 GstPad *srcpad = GST_PAD_CAST (user_data);
338 /* Stream start and caps have already been pushed */
339 if (GST_EVENT_TYPE (*event) >= GST_EVENT_SEGMENT)
340 gst_pad_push_event (srcpad, gst_event_ref (*event));
346 gst_rtp_pt_demux_chain (GstPad * pad, GstObject * parent, GstBuffer * buf)
348 GstFlowReturn ret = GST_FLOW_OK;
349 GstRtpPtDemux *rtpdemux;
353 GstRTPBuffer rtp = { NULL };
355 rtpdemux = GST_RTP_PT_DEMUX (parent);
357 if (!gst_rtp_buffer_map (buf, GST_MAP_READ, &rtp))
360 pt = gst_rtp_buffer_get_payload_type (&rtp);
361 gst_rtp_buffer_unmap (&rtp);
363 GST_DEBUG_OBJECT (rtpdemux, "received buffer for pt %d", pt);
365 srcpad = find_pad_for_pt (rtpdemux, pt);
366 if (srcpad == NULL) {
367 /* new PT, create a src pad */
368 GstRtpPtDemuxPad *rtpdemuxpad;
369 GstElementClass *klass;
370 GstPadTemplate *templ;
373 caps = gst_rtp_pt_demux_get_caps (rtpdemux, pt);
377 klass = GST_ELEMENT_GET_CLASS (rtpdemux);
378 templ = gst_element_class_get_pad_template (klass, "src_%u");
379 padname = g_strdup_printf ("src_%u", pt);
380 srcpad = gst_pad_new_from_template (templ, padname);
381 gst_pad_use_fixed_caps (srcpad);
383 gst_pad_set_event_function (srcpad, gst_rtp_pt_demux_src_event);
385 GST_DEBUG ("Adding pt=%d to the list.", pt);
386 rtpdemuxpad = g_slice_new0 (GstRtpPtDemuxPad);
387 rtpdemuxpad->pt = pt;
388 rtpdemuxpad->newcaps = FALSE;
389 rtpdemuxpad->pad = srcpad;
390 gst_object_ref (srcpad);
391 GST_OBJECT_LOCK (rtpdemux);
392 rtpdemux->srcpads = g_slist_append (rtpdemux->srcpads, rtpdemuxpad);
393 GST_OBJECT_UNLOCK (rtpdemux);
395 gst_pad_set_active (srcpad, TRUE);
398 /* First push the stream-start event, it must always come first */
399 gst_pad_push_event (srcpad,
400 gst_pad_get_sticky_event (rtpdemux->sink, GST_EVENT_STREAM_START, 0));
402 /* Then caps event is sent */
403 caps = gst_caps_make_writable (caps);
404 gst_caps_set_simple (caps, "payload", G_TYPE_INT, pt, NULL);
405 gst_pad_set_caps (srcpad, caps);
406 gst_caps_unref (caps);
408 /* First sticky events on sink pad are forwarded to the new src pad */
409 gst_pad_sticky_events_foreach (rtpdemux->sink, forward_sticky_events,
412 gst_element_add_pad (GST_ELEMENT_CAST (rtpdemux), srcpad);
414 GST_DEBUG ("emitting new-payload-type for pt %d", pt);
415 g_signal_emit (G_OBJECT (rtpdemux),
416 gst_rtp_pt_demux_signals[SIGNAL_NEW_PAYLOAD_TYPE], 0, pt, srcpad);
419 if (pt != rtpdemux->last_pt) {
422 /* our own signal with an extra flag that this is the only pad */
423 rtpdemux->last_pt = pt;
424 GST_DEBUG ("emitting payload-type-changed for pt %d", emit_pt);
425 g_signal_emit (G_OBJECT (rtpdemux),
426 gst_rtp_pt_demux_signals[SIGNAL_PAYLOAD_TYPE_CHANGE], 0, emit_pt);
429 while (need_caps_for_pt (rtpdemux, pt)) {
430 GST_DEBUG ("need new caps for %d", pt);
431 caps = gst_rtp_pt_demux_get_caps (rtpdemux, pt);
435 clear_newcaps_for_pt (rtpdemux, pt);
437 caps = gst_caps_make_writable (caps);
438 gst_caps_set_simple (caps, "payload", G_TYPE_INT, pt, NULL);
439 gst_pad_set_caps (srcpad, caps);
440 gst_caps_unref (caps);
444 ret = gst_pad_push (srcpad, buf);
446 gst_object_unref (srcpad);
453 /* this is fatal and should be filtered earlier */
454 GST_ELEMENT_ERROR (rtpdemux, STREAM, DECODE, (NULL),
455 ("Dropping invalid RTP payload"));
456 gst_buffer_unref (buf);
457 return GST_FLOW_ERROR;
461 GST_ELEMENT_ERROR (rtpdemux, STREAM, DECODE, (NULL),
462 ("Could not get caps for payload"));
463 gst_buffer_unref (buf);
465 gst_object_unref (srcpad);
466 return GST_FLOW_ERROR;
471 find_pad_for_pt (GstRtpPtDemux * rtpdemux, guint8 pt)
473 GstPad *respad = NULL;
476 GST_OBJECT_LOCK (rtpdemux);
477 for (walk = rtpdemux->srcpads; walk; walk = g_slist_next (walk)) {
478 GstRtpPtDemuxPad *pad = walk->data;
481 respad = gst_object_ref (pad->pad);
485 GST_OBJECT_UNLOCK (rtpdemux);
491 gst_rtp_pt_demux_sink_event (GstPad * pad, GstObject * parent, GstEvent * event)
493 GstRtpPtDemux *rtpdemux;
494 gboolean res = FALSE;
496 rtpdemux = GST_RTP_PT_DEMUX (parent);
498 switch (GST_EVENT_TYPE (event)) {
501 gst_rtp_pt_demux_clear_pt_map (rtpdemux);
502 /* don't forward the event, we cleared the ptmap and on the next buffer we
503 * will add the pt to the caps and push a new caps event */
504 gst_event_unref (event);
508 case GST_EVENT_CUSTOM_DOWNSTREAM:
510 const GstStructure *s;
512 s = gst_event_get_structure (event);
514 if (gst_structure_has_name (s, "GstRTPPacketLost")) {
515 GstPad *srcpad = find_pad_for_pt (rtpdemux, rtpdemux->last_pt);
518 res = gst_pad_push_event (srcpad, event);
519 gst_object_unref (srcpad);
521 gst_event_unref (event);
525 res = gst_pad_event_default (pad, parent, event);
530 res = gst_pad_event_default (pad, parent, event);
539 gst_rtp_pt_demux_src_event (GstPad * pad, GstObject * parent, GstEvent * event)
541 GstRtpPtDemux *demux;
542 const GstStructure *s;
544 demux = GST_RTP_PT_DEMUX (parent);
546 switch (GST_EVENT_TYPE (event)) {
547 case GST_EVENT_CUSTOM_UPSTREAM:
548 case GST_EVENT_CUSTOM_BOTH:
549 case GST_EVENT_CUSTOM_BOTH_OOB:
550 s = gst_event_get_structure (event);
551 if (s && !gst_structure_has_field (s, "payload")) {
554 GST_OBJECT_LOCK (demux);
555 for (walk = demux->srcpads; walk; walk = g_slist_next (walk)) {
556 GstRtpPtDemuxPad *dpad = (GstRtpPtDemuxPad *) walk->data;
558 if (dpad->pad == pad) {
562 GST_EVENT_CAST (gst_mini_object_make_writable
563 (GST_MINI_OBJECT_CAST (event)));
564 ws = gst_event_writable_structure (event);
565 gst_structure_set (ws, "payload", G_TYPE_UINT, dpad->pt, NULL);
569 GST_OBJECT_UNLOCK (demux);
576 return gst_pad_event_default (pad, parent, event);
580 * Reserves resources for the object.
583 gst_rtp_pt_demux_setup (GstRtpPtDemux * ptdemux)
585 ptdemux->srcpads = NULL;
586 ptdemux->last_pt = 0xFFFF;
592 * Free resources for the object.
595 gst_rtp_pt_demux_release (GstRtpPtDemux * ptdemux)
600 GST_OBJECT_LOCK (ptdemux);
601 tmppads = ptdemux->srcpads;
602 ptdemux->srcpads = NULL;
603 GST_OBJECT_UNLOCK (ptdemux);
605 for (walk = tmppads; walk; walk = g_slist_next (walk)) {
606 GstRtpPtDemuxPad *pad = walk->data;
608 gst_pad_set_active (pad->pad, FALSE);
609 gst_element_remove_pad (GST_ELEMENT_CAST (ptdemux), pad->pad);
610 g_slice_free (GstRtpPtDemuxPad, pad);
612 g_slist_free (tmppads);
615 static GstStateChangeReturn
616 gst_rtp_pt_demux_change_state (GstElement * element, GstStateChange transition)
618 GstStateChangeReturn ret;
619 GstRtpPtDemux *ptdemux;
621 ptdemux = GST_RTP_PT_DEMUX (element);
623 switch (transition) {
624 case GST_STATE_CHANGE_NULL_TO_READY:
625 if (gst_rtp_pt_demux_setup (ptdemux) != TRUE)
626 ret = GST_STATE_CHANGE_FAILURE;
628 case GST_STATE_CHANGE_READY_TO_PAUSED:
629 case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
634 ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
636 switch (transition) {
637 case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
638 case GST_STATE_CHANGE_PAUSED_TO_READY:
640 case GST_STATE_CHANGE_READY_TO_NULL:
641 gst_rtp_pt_demux_release (ptdemux);