1 /* GStreamer plugin for forward error correction
2 * Copyright (C) 2017 Pexip
3 *
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
8 *
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 * Lesser General Public License for more details.
13 *
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with this library; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17 *
18 * Author: Mikhail Fludkov <misha@pexip.com>
19 */
20
21 /**
22 * SECTION:element-rtpulpfecdec
23 * @short_description: Generic RTP Forward Error Correction (FEC) decoder
24 * @title: rtpulpfecdec
25 *
26 * Generic Forward Error Correction (FEC) decoder for Uneven Level
27 * Protection (ULP) as described in RFC 5109.
28 *
29 * It differs from the RFC in one important way, it multiplexes the
30 * FEC packets in the same sequence number as media packets. This is to be
31 * compatible with libwebrtc as using in Google Chrome and with Microsoft
32 * Lync / Skype for Business.
33 *
34 * This element will work in combination with an upstream #GstRtpStorage
35 * element and attempt to recover packets declared lost through custom
36 * 'GstRTPPacketLost' events, usually emitted by #GstRtpJitterBuffer.
37 *
38 * If no storage is provided using the #GstRtpUlpFecDec:storage
39 * property, it will try to get it from an element upstream.
40 *
41 * Additionally, the payload types of the protection packets *must* be
42 * provided to this element via its #GstRtpUlpFecDec:pt property.
43 *
44 * When using #GstRtpBin, this element should be inserted through the
45 * #GstRtpBin::request-fec-decoder signal.
46 *
47 * <refsect2>
48 * <title>Example pipeline</title>
49 * |[
50 * gst-launch-1.0 udpsrc port=8888 caps="application/x-rtp, payload=96, clock-rate=90000" ! rtpstorage size-time=220000000 ! rtpssrcdemux ! application/x-rtp, payload=96, clock-rate=90000, media=video, encoding-name=H264 ! rtpjitterbuffer do-lost=1 latency=200 ! rtpulpfecdec pt=122 ! rtph264depay ! avdec_h264 ! videoconvert ! autovideosink
51 * ]| This example will receive a stream with FEC and try to reconstruct the packets.
52 *
53 * Example programs are available at
54 * <ulink url="https://gitlab.freedesktop.org/gstreamer/gstreamer-rs/blob/master/examples/src/bin/rtpfecserver.rs">rtpfecserver.rs</ulink>
55 * and
56 * <ulink url="https://gitlab.freedesktop.org/gstreamer/gstreamer-rs/blob/master/examples/src/bin/rtpfecclient.rs">rtpfecclient.rs</ulink>
57 *
58 * </refsect2>
59 *
60 * See also: #GstRtpUlpFecEnc, #GstRtpBin, #GstRtpStorage
61 * Since: 1.14
62 */
63
64 #include <gst/rtp/gstrtpbuffer.h>
65 #include <gst/rtp/gstrtp-enumtypes.h>
66
67 #include "rtpulpfeccommon.h"
68 #include "gstrtpulpfecdec.h"
69
70 static GstStaticPadTemplate sinktemplate = GST_STATIC_PAD_TEMPLATE ("sink",
71 GST_PAD_SINK,
72 GST_PAD_ALWAYS,
73 GST_STATIC_CAPS ("application/x-rtp")
74 );
75
76 static GstStaticPadTemplate srctemplate = GST_STATIC_PAD_TEMPLATE ("src",
77 GST_PAD_SRC,
78 GST_PAD_ALWAYS,
79 GST_STATIC_CAPS ("application/x-rtp")
80 );
81
82 enum
83 {
84 PROP_0,
85 PROP_PT,
86 PROP_STORAGE,
87 PROP_RECOVERED,
88 PROP_UNRECOVERED,
89 N_PROPERTIES
90 };
91
92 #define DEFAULT_FEC_PT 0
93
94 static GParamSpec *klass_properties[N_PROPERTIES] = { NULL, };
95
96 GST_DEBUG_CATEGORY (gst_rtp_ulpfec_dec_debug);
97 #define GST_CAT_DEFAULT (gst_rtp_ulpfec_dec_debug)
98
99 G_DEFINE_TYPE (GstRtpUlpFecDec, gst_rtp_ulpfec_dec, GST_TYPE_ELEMENT);
100
101 #define RTP_FEC_MAP_INFO_NTH(dec, data) (&g_array_index (\
102 ((GstRtpUlpFecDec *)dec)->info_arr, \
103 RtpUlpFecMapInfo, \
104 GPOINTER_TO_UINT(data)))
105
106 static gint
_compare_fec_map_info(gconstpointer a,gconstpointer b,gpointer userdata)107 _compare_fec_map_info (gconstpointer a, gconstpointer b, gpointer userdata)
108 {
109 guint16 aseq =
110 gst_rtp_buffer_get_seq (&RTP_FEC_MAP_INFO_NTH (userdata, a)->rtp);
111 guint16 bseq =
112 gst_rtp_buffer_get_seq (&RTP_FEC_MAP_INFO_NTH (userdata, b)->rtp);
113 return gst_rtp_buffer_compare_seqnum (bseq, aseq);
114 }
115
116 static void
gst_rtp_ulpfec_dec_start(GstRtpUlpFecDec * self,GstBufferList * buflist,guint8 fec_pt,guint16 lost_seq)117 gst_rtp_ulpfec_dec_start (GstRtpUlpFecDec * self, GstBufferList * buflist,
118 guint8 fec_pt, guint16 lost_seq)
119 {
120 guint fec_packets = 0;
121 gsize i;
122
123 g_assert (NULL == self->info_media);
124 g_assert (0 == self->info_fec->len);
125 g_assert (0 == self->info_arr->len);
126
127 g_array_set_size (self->info_arr, gst_buffer_list_length (buflist));
128
129 for (i = 0;
130 i < gst_buffer_list_length (buflist) && !self->lost_packet_from_storage;
131 ++i) {
132 GstBuffer *buffer = gst_buffer_list_get (buflist, i);
133 RtpUlpFecMapInfo *info = RTP_FEC_MAP_INFO_NTH (self, i);
134
135 if (!rtp_ulpfec_map_info_map (gst_buffer_ref (buffer), info))
136 g_assert_not_reached ();
137
138 if (fec_pt == gst_rtp_buffer_get_payload_type (&info->rtp)) {
139 GST_DEBUG_RTP_PACKET (self, "rtp header (fec)", &info->rtp);
140
141 ++fec_packets;
142 if (rtp_ulpfec_buffer_is_valid (&info->rtp)) {
143 GST_DEBUG_FEC_PACKET (self, &info->rtp);
144 g_ptr_array_add (self->info_fec, GUINT_TO_POINTER (i));
145 }
146 } else {
147 GST_LOG_RTP_PACKET (self, "rtp header (incoming)", &info->rtp);
148
149 if (lost_seq == gst_rtp_buffer_get_seq (&info->rtp)) {
150 GST_DEBUG_OBJECT (self, "Received lost packet from the storage");
151 g_list_free (self->info_media);
152 self->info_media = NULL;
153 self->lost_packet_from_storage = TRUE;
154 }
155 self->info_media =
156 g_list_insert_sorted_with_data (self->info_media,
157 GUINT_TO_POINTER (i), _compare_fec_map_info, self);
158 }
159 }
160 if (!self->lost_packet_from_storage) {
161 self->fec_packets_received += fec_packets;
162 self->fec_packets_rejected += fec_packets - self->info_fec->len;
163 }
164 }
165
166 static void
gst_rtp_ulpfec_dec_stop(GstRtpUlpFecDec * self)167 gst_rtp_ulpfec_dec_stop (GstRtpUlpFecDec * self)
168 {
169 g_array_set_size (self->info_arr, 0);
170 g_ptr_array_set_size (self->info_fec, 0);
171 g_list_free (self->info_media);
172 self->info_media = NULL;
173 self->lost_packet_from_storage = FALSE;
174 self->lost_packet_returned = FALSE;
175 }
176
177 static guint64
gst_rtp_ulpfec_dec_get_media_buffers_mask(GstRtpUlpFecDec * self,guint16 fec_seq_base)178 gst_rtp_ulpfec_dec_get_media_buffers_mask (GstRtpUlpFecDec * self,
179 guint16 fec_seq_base)
180 {
181 guint64 mask = 0;
182 GList *it;
183
184 for (it = self->info_media; it; it = it->next) {
185 RtpUlpFecMapInfo *info = RTP_FEC_MAP_INFO_NTH (self, it->data);
186 mask |=
187 rtp_ulpfec_packet_mask_from_seqnum (gst_rtp_buffer_get_seq (&info->rtp),
188 fec_seq_base, TRUE);
189 }
190 return mask;
191 }
192
193 static gboolean
gst_rtp_ulpfec_dec_is_recovered_pt_valid(GstRtpUlpFecDec * self,gint media_pt,guint8 recovered_pt)194 gst_rtp_ulpfec_dec_is_recovered_pt_valid (GstRtpUlpFecDec * self, gint media_pt,
195 guint8 recovered_pt)
196 {
197 GList *it;
198 if (media_pt == recovered_pt)
199 return TRUE;
200
201 for (it = self->info_media; it; it = it->next) {
202 RtpUlpFecMapInfo *info = RTP_FEC_MAP_INFO_NTH (self, it->data);
203 if (gst_rtp_buffer_get_payload_type (&info->rtp) == recovered_pt)
204 return TRUE;
205 }
206 return FALSE;
207 }
208
209 static GstBuffer *
gst_rtp_ulpfec_dec_recover_from_fec(GstRtpUlpFecDec * self,RtpUlpFecMapInfo * info_fec,guint32 ssrc,gint media_pt,guint16 seq,guint8 * dst_pt)210 gst_rtp_ulpfec_dec_recover_from_fec (GstRtpUlpFecDec * self,
211 RtpUlpFecMapInfo * info_fec, guint32 ssrc, gint media_pt, guint16 seq,
212 guint8 * dst_pt)
213 {
214 guint64 fec_mask = rtp_ulpfec_buffer_get_mask (&info_fec->rtp);
215 gboolean fec_mask_long = rtp_ulpfec_buffer_get_fechdr (&info_fec->rtp)->L;
216 guint16 fec_seq_base = rtp_ulpfec_buffer_get_seq_base (&info_fec->rtp);
217 GstBuffer *ret;
218 GList *it;
219
220 g_array_set_size (self->scratch_buf, 0);
221 rtp_buffer_to_ulpfec_bitstring (&info_fec->rtp, self->scratch_buf, TRUE,
222 fec_mask_long);
223
224 for (it = self->info_media; it; it = it->next) {
225 RtpUlpFecMapInfo *info = RTP_FEC_MAP_INFO_NTH (self, it->data);
226 guint64 packet_mask =
227 rtp_ulpfec_packet_mask_from_seqnum (gst_rtp_buffer_get_seq (&info->rtp),
228 fec_seq_base, TRUE);
229
230 if (fec_mask & packet_mask) {
231 fec_mask ^= packet_mask;
232 rtp_buffer_to_ulpfec_bitstring (&info->rtp, self->scratch_buf, FALSE,
233 fec_mask_long);
234 }
235 }
236
237 ret =
238 rtp_ulpfec_bitstring_to_media_rtp_buffer (self->scratch_buf,
239 fec_mask_long, ssrc, seq);
240 if (ret) {
241 /* We are about to put recovered packet back in self->info_media to be able
242 * to reuse it later for recovery of other packets
243 **/
244 gint i = self->info_arr->len;
245 RtpUlpFecMapInfo *info;
246 guint8 recovered_pt;
247
248 g_array_set_size (self->info_arr, self->info_arr->len + 1);
249 info = RTP_FEC_MAP_INFO_NTH (self, i);
250
251 if (!rtp_ulpfec_map_info_map (gst_buffer_ref (ret), info)) {
252 GST_WARNING_OBJECT (self, "Invalid recovered packet");
253 goto recovered_packet_invalid;
254 }
255
256 recovered_pt = gst_rtp_buffer_get_payload_type (&info->rtp);
257 if (!gst_rtp_ulpfec_dec_is_recovered_pt_valid (self, media_pt,
258 recovered_pt)) {
259 GST_WARNING_OBJECT (self,
260 "Recovered packet has unexpected payload type (%u)", recovered_pt);
261 goto recovered_packet_invalid;
262 }
263
264 GST_DEBUG_RTP_PACKET (self, "rtp header (recovered)", &info->rtp);
265 self->info_media =
266 g_list_insert_sorted_with_data (self->info_media, GUINT_TO_POINTER (i),
267 _compare_fec_map_info, self);
268 *dst_pt = recovered_pt;
269 }
270 return ret;
271
272 recovered_packet_invalid:
273 g_array_set_size (self->info_arr, self->info_arr->len - 1);
274 gst_buffer_unref (ret);
275 return NULL;
276 }
277
278 static GstBuffer *
gst_rtp_ulpfec_dec_recover_from_storage(GstRtpUlpFecDec * self,guint8 * dst_pt,guint16 * dst_seq)279 gst_rtp_ulpfec_dec_recover_from_storage (GstRtpUlpFecDec * self,
280 guint8 * dst_pt, guint16 * dst_seq)
281 {
282 RtpUlpFecMapInfo *info;
283
284 if (self->lost_packet_returned)
285 return NULL;
286
287 g_assert (g_list_length (self->info_media) == 1);
288
289 info = RTP_FEC_MAP_INFO_NTH (self, self->info_media->data);
290 *dst_seq = gst_rtp_buffer_get_seq (&info->rtp);
291 *dst_pt = gst_rtp_buffer_get_payload_type (&info->rtp);
292 self->lost_packet_returned = TRUE;
293 GST_DEBUG_RTP_PACKET (self, "rtp header (recovered)", &info->rtp);
294 return gst_buffer_ref (info->rtp.buffer);
295 }
296
297 /* __has_builtin only works with clang, so test compiler version for gcc */
298 /* Intel compiler and MSVC probably have their own things as well */
299 /* TODO: make sure we use builtin for clang as well */
300 #if defined(__GNUC__) && __GNUC__ >= 4
301 #define rtp_ulpfec_ctz64 __builtin_ctzll
302 #else
303 static inline gint
rtp_ulpfec_ctz64_inline(guint64 mask)304 rtp_ulpfec_ctz64_inline (guint64 mask)
305 {
306 gint nth_bit = 0;
307
308 do {
309 if ((mask & 1))
310 return nth_bit;
311 mask = mask >> 1;
312 } while (++nth_bit < 64);
313
314 return -1; /* should not be reached, since mask must not be 0 */
315 }
316
317 #define rtp_ulpfec_ctz64 rtp_ulpfec_ctz64_inline
318 #endif
319
320 static GstBuffer *
gst_rtp_ulpfec_dec_recover(GstRtpUlpFecDec * self,guint32 ssrc,gint media_pt,guint8 * dst_pt,guint16 * dst_seq)321 gst_rtp_ulpfec_dec_recover (GstRtpUlpFecDec * self, guint32 ssrc, gint media_pt,
322 guint8 * dst_pt, guint16 * dst_seq)
323 {
324 guint64 media_mask = 0;
325 gint media_mask_seq_base = -1;
326 gsize i;
327
328 if (self->lost_packet_from_storage)
329 return gst_rtp_ulpfec_dec_recover_from_storage (self, dst_pt, dst_seq);
330
331 /* Looking for a FEC packet which can be used for recovery */
332 for (i = 0; i < self->info_fec->len; ++i) {
333 RtpUlpFecMapInfo *info = RTP_FEC_MAP_INFO_NTH (self,
334 g_ptr_array_index (self->info_fec, i));
335 guint16 seq_base = rtp_ulpfec_buffer_get_seq_base (&info->rtp);
336 guint64 fec_mask = rtp_ulpfec_buffer_get_mask (&info->rtp);
337 guint64 missing_packets_mask;
338
339 if (media_mask_seq_base != (gint) seq_base) {
340 media_mask_seq_base = seq_base;
341 media_mask = gst_rtp_ulpfec_dec_get_media_buffers_mask (self, seq_base);
342 }
343
344 /* media_mask has 1s if packet exist.
345 * fec_mask is the mask of protected packets
346 * The statement below excludes existing packets from the protected. So
347 * we are left with 1s only for missing packets which can be recovered
348 * by this FEC packet. */
349 missing_packets_mask = fec_mask & (~media_mask);
350
351 /* Do we have any 1s? Checking if current FEC packet can be used for recovery */
352 if (0 != missing_packets_mask) {
353 guint trailing_zeros = rtp_ulpfec_ctz64 (missing_packets_mask);
354
355 /* Is it the only 1 in the mask? Checking if we lacking single packet in
356 * that case FEC packet can be used for recovery */
357 if (missing_packets_mask == (G_GUINT64_CONSTANT (1) << trailing_zeros)) {
358 GstBuffer *ret;
359
360 *dst_seq =
361 seq_base + (RTP_ULPFEC_SEQ_BASE_OFFSET_MAX (TRUE) - trailing_zeros);
362 ret =
363 gst_rtp_ulpfec_dec_recover_from_fec (self, info, ssrc, media_pt,
364 *dst_seq, dst_pt);
365 if (ret)
366 return ret;
367 }
368 }
369 }
370 return NULL;
371 }
372
373 static GstFlowReturn
gst_rtp_ulpfec_dec_chain(GstPad * pad,GstObject * parent,GstBuffer * buf)374 gst_rtp_ulpfec_dec_chain (GstPad * pad, GstObject * parent, GstBuffer * buf)
375 {
376 GstRtpUlpFecDec *self = GST_RTP_ULPFEC_DEC (parent);
377
378 if (G_LIKELY (GST_FLOW_OK == self->chain_return_val)) {
379 GstRTPBuffer rtp = GST_RTP_BUFFER_INIT;
380 buf = gst_buffer_make_writable (buf);
381
382 if (G_UNLIKELY (self->unset_discont_flag)) {
383 self->unset_discont_flag = FALSE;
384 GST_BUFFER_FLAG_UNSET (buf, GST_BUFFER_FLAG_DISCONT);
385 }
386
387 gst_rtp_buffer_map (buf, GST_MAP_WRITE, &rtp);
388 gst_rtp_buffer_set_seq (&rtp, self->next_seqnum++);
389 gst_rtp_buffer_unmap (&rtp);
390
391 return gst_pad_push (self->srcpad, buf);
392 }
393
394 gst_buffer_unref (buf);
395 return self->chain_return_val;
396 }
397
398 static gboolean
gst_rtp_ulpfec_dec_handle_packet_loss(GstRtpUlpFecDec * self,guint16 seqnum,GstClockTime timestamp,GstClockTime duration)399 gst_rtp_ulpfec_dec_handle_packet_loss (GstRtpUlpFecDec * self, guint16 seqnum,
400 GstClockTime timestamp, GstClockTime duration)
401 {
402 gint caps_pt = self->have_caps_pt ? self->caps_pt : -1;
403 gboolean ret = TRUE;
404 GstBufferList *buflist =
405 rtp_storage_get_packets_for_recovery (self->storage, self->fec_pt,
406 self->caps_ssrc, seqnum);
407
408 if (buflist) {
409 GstBuffer *recovered_buffer = NULL;
410 guint16 recovered_seq = 0;
411 guint8 recovered_pt = 0;
412
413 gst_rtp_ulpfec_dec_start (self, buflist, self->fec_pt, seqnum);
414
415 while (NULL != (recovered_buffer =
416 gst_rtp_ulpfec_dec_recover (self, self->caps_ssrc, caps_pt,
417 &recovered_pt, &recovered_seq))) {
418 if (seqnum == recovered_seq) {
419 GstBuffer *sent_buffer;
420 GstRTPBuffer rtp = GST_RTP_BUFFER_INIT;
421
422 recovered_buffer = gst_buffer_make_writable (recovered_buffer);
423 GST_BUFFER_PTS (recovered_buffer) = timestamp;
424 /* GST_BUFFER_DURATION (recovered_buffer) = duration;
425 * JB does not set the duration, so we will not too */
426
427 if (!self->lost_packet_from_storage)
428 rtp_storage_put_recovered_packet (self->storage,
429 recovered_buffer, recovered_pt, self->caps_ssrc, recovered_seq);
430
431 GST_DEBUG_OBJECT (self,
432 "Pushing recovered packet ssrc=0x%08x seq=%u %" GST_PTR_FORMAT,
433 self->caps_ssrc, seqnum, recovered_buffer);
434
435 sent_buffer = gst_buffer_copy_deep (recovered_buffer);
436
437 if (self->lost_packet_from_storage)
438 gst_buffer_unref (recovered_buffer);
439
440 gst_rtp_buffer_map (sent_buffer, GST_MAP_WRITE, &rtp);
441 gst_rtp_buffer_set_seq (&rtp, self->next_seqnum++);
442 gst_rtp_buffer_unmap (&rtp);
443
444 ret = FALSE;
445 self->unset_discont_flag = TRUE;
446 self->chain_return_val = gst_pad_push (self->srcpad, sent_buffer);
447 break;
448 }
449
450 if (!self->lost_packet_from_storage) {
451 rtp_storage_put_recovered_packet (self->storage,
452 recovered_buffer, recovered_pt, self->caps_ssrc, recovered_seq);
453 } else {
454 gst_buffer_unref (recovered_buffer);
455 }
456 }
457
458 gst_rtp_ulpfec_dec_stop (self);
459 gst_buffer_list_unref (buflist);
460 }
461
462 GST_DEBUG_OBJECT (self, "Packet lost ssrc=0x%08x seq=%u", self->caps_ssrc,
463 seqnum);
464
465 return ret;
466 }
467
468 static gboolean
gst_rtp_ulpfec_dec_handle_sink_event(GstPad * pad,GstObject * parent,GstEvent * event)469 gst_rtp_ulpfec_dec_handle_sink_event (GstPad * pad, GstObject * parent,
470 GstEvent * event)
471 {
472 GstRtpUlpFecDec *self = GST_RTP_ULPFEC_DEC (parent);
473 gboolean forward = TRUE;
474
475 GST_LOG_OBJECT (self, "Received event %" GST_PTR_FORMAT, event);
476
477 if (GST_FLOW_OK == self->chain_return_val &&
478 GST_EVENT_CUSTOM_DOWNSTREAM == GST_EVENT_TYPE (event) &&
479 gst_event_has_name (event, "GstRTPPacketLost")) {
480 guint seqnum;
481 GstClockTime timestamp, duration;
482 GstStructure *s;
483
484 event = gst_event_make_writable (event);
485 s = gst_event_writable_structure (event);
486
487 g_assert (self->have_caps_ssrc);
488
489 if (self->storage == NULL) {
490 GstQuery *q = gst_query_new_custom (GST_QUERY_CUSTOM,
491 gst_structure_new_empty ("GstRtpStorage"));
492
493 if (gst_pad_peer_query (self->sinkpad, q)) {
494 const GstStructure *s = gst_query_get_structure (q);
495
496 if (gst_structure_has_field_typed (s, "storage", G_TYPE_OBJECT)) {
497 gst_structure_get (s, "storage", G_TYPE_OBJECT, &self->storage, NULL);
498 }
499 }
500 gst_query_unref (q);
501 }
502
503 if (self->storage == NULL) {
504 GST_ELEMENT_WARNING (self, STREAM, FAILED, ("Internal storage not found"),
505 ("You need to add rtpstorage element upstream from rtpulpfecdec."));
506 return FALSE;
507 }
508
509 if (!gst_structure_get (s,
510 "seqnum", G_TYPE_UINT, &seqnum,
511 "timestamp", G_TYPE_UINT64, ×tamp,
512 "duration", G_TYPE_UINT64, &duration, NULL))
513 g_assert_not_reached ();
514
515 forward =
516 gst_rtp_ulpfec_dec_handle_packet_loss (self, seqnum, timestamp,
517 duration);
518
519 if (forward) {
520 gst_structure_remove_field (s, "seqnum");
521 gst_structure_set (s, "might-have-been-fec", G_TYPE_BOOLEAN, TRUE, NULL);
522 ++self->packets_unrecovered;
523 } else {
524 ++self->packets_recovered;
525 }
526
527 GST_DEBUG_OBJECT (self, "Unrecovered / Recovered: %lu / %lu",
528 (gulong) self->packets_unrecovered, (gulong) self->packets_recovered);
529 } else if (GST_EVENT_CAPS == GST_EVENT_TYPE (event)) {
530 GstCaps *caps;
531 gboolean have_caps_pt = FALSE;
532 gboolean have_caps_ssrc = FALSE;
533 guint caps_ssrc = 0;
534 gint caps_pt = 0;
535
536 gst_event_parse_caps (event, &caps);
537 have_caps_ssrc =
538 gst_structure_get_uint (gst_caps_get_structure (caps, 0), "ssrc",
539 &caps_ssrc);
540 have_caps_pt =
541 gst_structure_get_int (gst_caps_get_structure (caps, 0), "payload",
542 &caps_pt);
543
544 if (self->have_caps_ssrc != have_caps_ssrc || self->caps_ssrc != caps_ssrc)
545 GST_DEBUG_OBJECT (self, "SSRC changed %u, 0x%08x -> %u, 0x%08x",
546 self->have_caps_ssrc, self->caps_ssrc, have_caps_ssrc, caps_ssrc);
547 if (self->have_caps_pt != have_caps_pt || self->caps_pt != caps_pt)
548 GST_DEBUG_OBJECT (self, "PT changed %u, %u -> %u, %u",
549 self->have_caps_pt, self->caps_pt, have_caps_pt, caps_pt);
550
551 self->have_caps_ssrc = have_caps_ssrc;
552 self->have_caps_pt = have_caps_pt;
553 self->caps_ssrc = caps_ssrc;
554 self->caps_pt = caps_pt;
555 }
556
557 if (forward)
558 return gst_pad_push_event (self->srcpad, event);
559 gst_event_unref (event);
560 return TRUE;
561 }
562
563 static void
gst_rtp_ulpfec_dec_init(GstRtpUlpFecDec * self)564 gst_rtp_ulpfec_dec_init (GstRtpUlpFecDec * self)
565 {
566 self->srcpad = gst_pad_new_from_static_template (&srctemplate, "src");
567 self->sinkpad = gst_pad_new_from_static_template (&sinktemplate, "sink");
568 GST_PAD_SET_PROXY_CAPS (self->sinkpad);
569 GST_PAD_SET_PROXY_ALLOCATION (self->sinkpad);
570 gst_pad_set_chain_function (self->sinkpad,
571 GST_DEBUG_FUNCPTR (gst_rtp_ulpfec_dec_chain));
572 gst_pad_set_event_function (self->sinkpad,
573 GST_DEBUG_FUNCPTR (gst_rtp_ulpfec_dec_handle_sink_event));
574
575 gst_element_add_pad (GST_ELEMENT (self), self->srcpad);
576 gst_element_add_pad (GST_ELEMENT (self), self->sinkpad);
577
578 self->fec_pt = DEFAULT_FEC_PT;
579
580 self->next_seqnum = g_random_int_range (0, G_MAXINT16);
581
582 self->chain_return_val = GST_FLOW_OK;
583 self->have_caps_ssrc = FALSE;
584 self->caps_ssrc = 0;
585 self->info_fec = g_ptr_array_new ();
586 self->info_arr = g_array_new (FALSE, TRUE, sizeof (RtpUlpFecMapInfo));
587 g_array_set_clear_func (self->info_arr,
588 (GDestroyNotify) rtp_ulpfec_map_info_unmap);
589 self->scratch_buf = g_array_new (FALSE, TRUE, sizeof (guint8));
590 }
591
592 static void
gst_rtp_ulpfec_dec_dispose(GObject * obj)593 gst_rtp_ulpfec_dec_dispose (GObject * obj)
594 {
595 GstRtpUlpFecDec *self = GST_RTP_ULPFEC_DEC (obj);
596
597 GST_INFO_OBJECT (self,
598 " ssrc=0x%08x pt=%u"
599 " packets_recovered=%" G_GSIZE_FORMAT
600 " packets_unrecovered=%" G_GSIZE_FORMAT,
601 self->caps_ssrc, self->caps_pt,
602 self->packets_recovered, self->packets_unrecovered);
603
604 if (self->storage)
605 g_object_unref (self->storage);
606
607 g_assert (NULL == self->info_media);
608 g_assert (0 == self->info_fec->len);
609 g_assert (0 == self->info_arr->len);
610
611 if (self->fec_packets_received) {
612 GST_INFO_OBJECT (self,
613 " fec_packets_received=%" G_GSIZE_FORMAT
614 " fec_packets_rejected=%" G_GSIZE_FORMAT
615 " packets_rejected=%" G_GSIZE_FORMAT,
616 self->fec_packets_received,
617 self->fec_packets_rejected, self->packets_rejected);
618 }
619
620 g_ptr_array_free (self->info_fec, TRUE);
621 g_array_free (self->info_arr, TRUE);
622 g_array_free (self->scratch_buf, TRUE);
623
624 G_OBJECT_CLASS (gst_rtp_ulpfec_dec_parent_class)->dispose (obj);
625 }
626
627 static void
gst_rtp_ulpfec_dec_set_property(GObject * object,guint prop_id,const GValue * value,GParamSpec * pspec)628 gst_rtp_ulpfec_dec_set_property (GObject * object, guint prop_id,
629 const GValue * value, GParamSpec * pspec)
630 {
631 GstRtpUlpFecDec *self = GST_RTP_ULPFEC_DEC (object);
632
633 switch (prop_id) {
634 case PROP_PT:
635 self->fec_pt = g_value_get_uint (value);
636 break;
637 case PROP_STORAGE:
638 if (self->storage)
639 g_object_unref (self->storage);
640 self->storage = g_value_get_object (value);
641 if (self->storage)
642 g_object_ref (self->storage);
643 break;
644 default:
645 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
646 break;
647 }
648 }
649
650 static void
gst_rtp_ulpfec_dec_get_property(GObject * object,guint prop_id,GValue * value,GParamSpec * pspec)651 gst_rtp_ulpfec_dec_get_property (GObject * object, guint prop_id,
652 GValue * value, GParamSpec * pspec)
653 {
654 GstRtpUlpFecDec *self = GST_RTP_ULPFEC_DEC (object);
655
656 switch (prop_id) {
657 case PROP_PT:
658 g_value_set_uint (value, self->fec_pt);
659 break;
660 case PROP_STORAGE:
661 g_value_set_object (value, self->storage);
662 break;
663 case PROP_RECOVERED:
664 g_value_set_uint (value, (guint) self->packets_recovered);
665 break;
666 case PROP_UNRECOVERED:
667 g_value_set_uint (value, (guint) self->packets_unrecovered);
668 break;
669 default:
670 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
671 break;
672 }
673 }
674
675 static void
gst_rtp_ulpfec_dec_class_init(GstRtpUlpFecDecClass * klass)676 gst_rtp_ulpfec_dec_class_init (GstRtpUlpFecDecClass * klass)
677 {
678 GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
679 GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
680
681 GST_DEBUG_CATEGORY_INIT (gst_rtp_ulpfec_dec_debug,
682 "rtpulpfecdec", 0, "RTP FEC Decoder");
683
684 gst_element_class_add_pad_template (element_class,
685 gst_static_pad_template_get (&srctemplate));
686 gst_element_class_add_pad_template (element_class,
687 gst_static_pad_template_get (&sinktemplate));
688
689 gst_element_class_set_static_metadata (element_class,
690 "RTP FEC Decoder",
691 "Codec/Depayloader/Network/RTP",
692 "Decodes RTP FEC (RFC5109)", "Mikhail Fludkov <misha@pexip.com>");
693
694 gobject_class->set_property =
695 GST_DEBUG_FUNCPTR (gst_rtp_ulpfec_dec_set_property);
696 gobject_class->get_property =
697 GST_DEBUG_FUNCPTR (gst_rtp_ulpfec_dec_get_property);
698 gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_rtp_ulpfec_dec_dispose);
699
700 klass_properties[PROP_PT] = g_param_spec_uint ("pt", "pt",
701 "FEC packets payload type", 0, 127,
702 DEFAULT_FEC_PT, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS);
703 klass_properties[PROP_STORAGE] =
704 g_param_spec_object ("storage", "RTP storage", "RTP storage",
705 G_TYPE_OBJECT, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS);
706 klass_properties[PROP_RECOVERED] =
707 g_param_spec_uint ("recovered", "recovered",
708 "The number of recovered packets", 0, G_MAXUINT, 0,
709 G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
710 klass_properties[PROP_UNRECOVERED] =
711 g_param_spec_uint ("unrecovered", "unrecovered",
712 "The number of unrecovered packets", 0, G_MAXUINT, 0,
713 G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
714
715 g_object_class_install_properties (gobject_class, N_PROPERTIES,
716 klass_properties);
717
718 g_assert (rtp_ulpfec_ctz64 (G_GUINT64_CONSTANT (0x1)) == 0);
719 g_assert (rtp_ulpfec_ctz64 (G_GUINT64_CONSTANT (0x8000000000000000)) == 63);
720 }
721