1 /*
2 * Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 #include "webrtc/video_engine/vie_receiver.h"
12
13 #include <vector>
14
15 #include "webrtc/modules/remote_bitrate_estimator/include/remote_bitrate_estimator.h"
16 #include "webrtc/modules/rtp_rtcp/interface/fec_receiver.h"
17 #include "webrtc/modules/rtp_rtcp/interface/receive_statistics.h"
18 #include "webrtc/modules/rtp_rtcp/interface/remote_ntp_time_estimator.h"
19 #include "webrtc/modules/rtp_rtcp/interface/rtp_header_parser.h"
20 #include "webrtc/modules/rtp_rtcp/interface/rtp_payload_registry.h"
21 #include "webrtc/modules/rtp_rtcp/interface/rtp_receiver.h"
22 #include "webrtc/modules/rtp_rtcp/interface/rtp_rtcp.h"
23 #include "webrtc/modules/utility/interface/rtp_dump.h"
24 #include "webrtc/modules/video_coding/main/interface/video_coding.h"
25 #include "webrtc/system_wrappers/interface/critical_section_wrapper.h"
26 #include "webrtc/system_wrappers/interface/logging.h"
27 #include "webrtc/system_wrappers/interface/tick_util.h"
28 #include "webrtc/system_wrappers/interface/timestamp_extrapolator.h"
29 #include "webrtc/system_wrappers/interface/trace.h"
30
31 namespace webrtc {
32
ViEReceiver(const int32_t channel_id,VideoCodingModule * module_vcm,RemoteBitrateEstimator * remote_bitrate_estimator,RtpFeedback * rtp_feedback)33 ViEReceiver::ViEReceiver(const int32_t channel_id,
34 VideoCodingModule* module_vcm,
35 RemoteBitrateEstimator* remote_bitrate_estimator,
36 RtpFeedback* rtp_feedback)
37 : receive_cs_(CriticalSectionWrapper::CreateCriticalSection()),
38 rtp_header_parser_(RtpHeaderParser::Create()),
39 rtp_payload_registry_(new RTPPayloadRegistry(
40 RTPPayloadStrategy::CreateStrategy(false))),
41 rtp_receiver_(RtpReceiver::CreateVideoReceiver(
42 channel_id, Clock::GetRealTimeClock(), this, rtp_feedback,
43 rtp_payload_registry_.get())),
44 rtp_receive_statistics_(ReceiveStatistics::Create(
45 Clock::GetRealTimeClock())),
46 fec_receiver_(FecReceiver::Create(this)),
47 rtp_rtcp_(NULL),
48 vcm_(module_vcm),
49 remote_bitrate_estimator_(remote_bitrate_estimator),
50 ntp_estimator_(new RemoteNtpTimeEstimator(Clock::GetRealTimeClock())),
51 rtp_dump_(NULL),
52 receiving_(false),
53 restored_packet_in_use_(false),
54 receiving_ast_enabled_(false) {
55 assert(remote_bitrate_estimator);
56 }
57
~ViEReceiver()58 ViEReceiver::~ViEReceiver() {
59 if (rtp_dump_) {
60 rtp_dump_->Stop();
61 RtpDump::DestroyRtpDump(rtp_dump_);
62 rtp_dump_ = NULL;
63 }
64 }
65
SetReceiveCodec(const VideoCodec & video_codec)66 bool ViEReceiver::SetReceiveCodec(const VideoCodec& video_codec) {
67 int8_t old_pltype = -1;
68 if (rtp_payload_registry_->ReceivePayloadType(video_codec.plName,
69 kVideoPayloadTypeFrequency,
70 0,
71 video_codec.maxBitrate,
72 &old_pltype) != -1) {
73 rtp_payload_registry_->DeRegisterReceivePayload(old_pltype);
74 }
75
76 return RegisterPayload(video_codec);
77 }
78
RegisterPayload(const VideoCodec & video_codec)79 bool ViEReceiver::RegisterPayload(const VideoCodec& video_codec) {
80 return rtp_receiver_->RegisterReceivePayload(video_codec.plName,
81 video_codec.plType,
82 kVideoPayloadTypeFrequency,
83 0,
84 video_codec.maxBitrate) == 0;
85 }
86
SetNackStatus(bool enable,int max_nack_reordering_threshold)87 void ViEReceiver::SetNackStatus(bool enable,
88 int max_nack_reordering_threshold) {
89 if (!enable) {
90 // Reset the threshold back to the lower default threshold when NACK is
91 // disabled since we no longer will be receiving retransmissions.
92 max_nack_reordering_threshold = kDefaultMaxReorderingThreshold;
93 }
94 rtp_receive_statistics_->SetMaxReorderingThreshold(
95 max_nack_reordering_threshold);
96 rtp_receiver_->SetNACKStatus(enable ? kNackRtcp : kNackOff);
97 }
98
SetRtxPayloadType(int payload_type)99 void ViEReceiver::SetRtxPayloadType(int payload_type) {
100 rtp_payload_registry_->SetRtxPayloadType(payload_type);
101 }
102
SetRtxSsrc(uint32_t ssrc)103 void ViEReceiver::SetRtxSsrc(uint32_t ssrc) {
104 rtp_payload_registry_->SetRtxSsrc(ssrc);
105 }
106
GetRemoteSsrc() const107 uint32_t ViEReceiver::GetRemoteSsrc() const {
108 return rtp_receiver_->SSRC();
109 }
110
GetCsrcs(uint32_t * csrcs) const111 int ViEReceiver::GetCsrcs(uint32_t* csrcs) const {
112 return rtp_receiver_->CSRCs(csrcs);
113 }
114
SetRtpRtcpModule(RtpRtcp * module)115 void ViEReceiver::SetRtpRtcpModule(RtpRtcp* module) {
116 rtp_rtcp_ = module;
117 }
118
GetRtpReceiver() const119 RtpReceiver* ViEReceiver::GetRtpReceiver() const {
120 return rtp_receiver_.get();
121 }
122
RegisterSimulcastRtpRtcpModules(const std::list<RtpRtcp * > & rtp_modules)123 void ViEReceiver::RegisterSimulcastRtpRtcpModules(
124 const std::list<RtpRtcp*>& rtp_modules) {
125 CriticalSectionScoped cs(receive_cs_.get());
126 rtp_rtcp_simulcast_.clear();
127
128 if (!rtp_modules.empty()) {
129 rtp_rtcp_simulcast_.insert(rtp_rtcp_simulcast_.begin(),
130 rtp_modules.begin(),
131 rtp_modules.end());
132 }
133 }
134
SetReceiveTimestampOffsetStatus(bool enable,int id)135 bool ViEReceiver::SetReceiveTimestampOffsetStatus(bool enable, int id) {
136 if (enable) {
137 return rtp_header_parser_->RegisterRtpHeaderExtension(
138 kRtpExtensionTransmissionTimeOffset, id);
139 } else {
140 return rtp_header_parser_->DeregisterRtpHeaderExtension(
141 kRtpExtensionTransmissionTimeOffset);
142 }
143 }
144
SetReceiveAbsoluteSendTimeStatus(bool enable,int id)145 bool ViEReceiver::SetReceiveAbsoluteSendTimeStatus(bool enable, int id) {
146 if (enable) {
147 if (rtp_header_parser_->RegisterRtpHeaderExtension(
148 kRtpExtensionAbsoluteSendTime, id)) {
149 receiving_ast_enabled_ = true;
150 return true;
151 } else {
152 return false;
153 }
154 } else {
155 receiving_ast_enabled_ = false;
156 return rtp_header_parser_->DeregisterRtpHeaderExtension(
157 kRtpExtensionAbsoluteSendTime);
158 }
159 }
160
ReceivedRTPPacket(const void * rtp_packet,int rtp_packet_length,const PacketTime & packet_time)161 int ViEReceiver::ReceivedRTPPacket(const void* rtp_packet,
162 int rtp_packet_length,
163 const PacketTime& packet_time) {
164 return InsertRTPPacket(static_cast<const uint8_t*>(rtp_packet),
165 rtp_packet_length, packet_time);
166 }
167
ReceivedRTCPPacket(const void * rtcp_packet,int rtcp_packet_length)168 int ViEReceiver::ReceivedRTCPPacket(const void* rtcp_packet,
169 int rtcp_packet_length) {
170 return InsertRTCPPacket(static_cast<const uint8_t*>(rtcp_packet),
171 rtcp_packet_length);
172 }
173
OnReceivedPayloadData(const uint8_t * payload_data,const uint16_t payload_size,const WebRtcRTPHeader * rtp_header)174 int32_t ViEReceiver::OnReceivedPayloadData(
175 const uint8_t* payload_data, const uint16_t payload_size,
176 const WebRtcRTPHeader* rtp_header) {
177 WebRtcRTPHeader rtp_header_with_ntp = *rtp_header;
178 rtp_header_with_ntp.ntp_time_ms =
179 ntp_estimator_->Estimate(rtp_header->header.timestamp);
180 if (vcm_->IncomingPacket(payload_data,
181 payload_size,
182 rtp_header_with_ntp) != 0) {
183 // Check this...
184 return -1;
185 }
186 return 0;
187 }
188
OnRecoveredPacket(const uint8_t * rtp_packet,int rtp_packet_length)189 bool ViEReceiver::OnRecoveredPacket(const uint8_t* rtp_packet,
190 int rtp_packet_length) {
191 RTPHeader header;
192 if (!rtp_header_parser_->Parse(rtp_packet, rtp_packet_length, &header)) {
193 return false;
194 }
195 header.payload_type_frequency = kVideoPayloadTypeFrequency;
196 return ReceivePacket(rtp_packet, rtp_packet_length, header, false);
197 }
198
ReceivedBWEPacket(int64_t arrival_time_ms,int payload_size,const RTPHeader & header)199 void ViEReceiver::ReceivedBWEPacket(
200 int64_t arrival_time_ms, int payload_size, const RTPHeader& header) {
201 // Only forward if the incoming packet *and* the channel are both configured
202 // to receive absolute sender time. RTP time stamps may have different rates
203 // for audio and video and shouldn't be mixed.
204 if (header.extension.hasAbsoluteSendTime && receiving_ast_enabled_) {
205 remote_bitrate_estimator_->IncomingPacket(arrival_time_ms, payload_size,
206 header);
207 }
208 }
209
InsertRTPPacket(const uint8_t * rtp_packet,int rtp_packet_length,const PacketTime & packet_time)210 int ViEReceiver::InsertRTPPacket(const uint8_t* rtp_packet,
211 int rtp_packet_length,
212 const PacketTime& packet_time) {
213 {
214 CriticalSectionScoped cs(receive_cs_.get());
215 if (!receiving_) {
216 return -1;
217 }
218 if (rtp_dump_) {
219 rtp_dump_->DumpPacket(rtp_packet,
220 static_cast<uint16_t>(rtp_packet_length));
221 }
222 }
223
224 RTPHeader header;
225 if (!rtp_header_parser_->Parse(rtp_packet, rtp_packet_length,
226 &header)) {
227 return -1;
228 }
229 int payload_length = rtp_packet_length - header.headerLength;
230 int64_t arrival_time_ms;
231 if (packet_time.timestamp != -1)
232 arrival_time_ms = (packet_time.timestamp + 500) / 1000;
233 else
234 arrival_time_ms = TickTime::MillisecondTimestamp();
235
236 remote_bitrate_estimator_->IncomingPacket(arrival_time_ms,
237 payload_length, header);
238 header.payload_type_frequency = kVideoPayloadTypeFrequency;
239
240 bool in_order = IsPacketInOrder(header);
241 rtp_payload_registry_->SetIncomingPayloadType(header);
242 int ret = ReceivePacket(rtp_packet, rtp_packet_length, header, in_order)
243 ? 0
244 : -1;
245 // Update receive statistics after ReceivePacket.
246 // Receive statistics will be reset if the payload type changes (make sure
247 // that the first packet is included in the stats).
248 rtp_receive_statistics_->IncomingPacket(
249 header, rtp_packet_length, IsPacketRetransmitted(header, in_order));
250 return ret;
251 }
252
ReceivePacket(const uint8_t * packet,int packet_length,const RTPHeader & header,bool in_order)253 bool ViEReceiver::ReceivePacket(const uint8_t* packet,
254 int packet_length,
255 const RTPHeader& header,
256 bool in_order) {
257 if (rtp_payload_registry_->IsEncapsulated(header)) {
258 return ParseAndHandleEncapsulatingHeader(packet, packet_length, header);
259 }
260 const uint8_t* payload = packet + header.headerLength;
261 int payload_length = packet_length - header.headerLength;
262 assert(payload_length >= 0);
263 PayloadUnion payload_specific;
264 if (!rtp_payload_registry_->GetPayloadSpecifics(header.payloadType,
265 &payload_specific)) {
266 return false;
267 }
268 return rtp_receiver_->IncomingRtpPacket(header, payload, payload_length,
269 payload_specific, in_order);
270 }
271
ParseAndHandleEncapsulatingHeader(const uint8_t * packet,int packet_length,const RTPHeader & header)272 bool ViEReceiver::ParseAndHandleEncapsulatingHeader(const uint8_t* packet,
273 int packet_length,
274 const RTPHeader& header) {
275 if (rtp_payload_registry_->IsRed(header)) {
276 int8_t ulpfec_pt = rtp_payload_registry_->ulpfec_payload_type();
277 if (packet[header.headerLength] == ulpfec_pt)
278 rtp_receive_statistics_->FecPacketReceived(header.ssrc);
279 if (fec_receiver_->AddReceivedRedPacket(
280 header, packet, packet_length, ulpfec_pt) != 0) {
281 return false;
282 }
283 return fec_receiver_->ProcessReceivedFec() == 0;
284 } else if (rtp_payload_registry_->IsRtx(header)) {
285 if (header.headerLength + header.paddingLength == packet_length) {
286 // This is an empty packet and should be silently dropped before trying to
287 // parse the RTX header.
288 return true;
289 }
290 // Remove the RTX header and parse the original RTP header.
291 if (packet_length < header.headerLength)
292 return false;
293 if (packet_length > static_cast<int>(sizeof(restored_packet_)))
294 return false;
295 CriticalSectionScoped cs(receive_cs_.get());
296 if (restored_packet_in_use_) {
297 LOG(LS_WARNING) << "Multiple RTX headers detected, dropping packet.";
298 return false;
299 }
300 uint8_t* restored_packet_ptr = restored_packet_;
301 if (!rtp_payload_registry_->RestoreOriginalPacket(
302 &restored_packet_ptr, packet, &packet_length, rtp_receiver_->SSRC(),
303 header)) {
304 LOG(LS_WARNING) << "Incoming RTX packet: Invalid RTP header";
305 return false;
306 }
307 restored_packet_in_use_ = true;
308 bool ret = OnRecoveredPacket(restored_packet_ptr, packet_length);
309 restored_packet_in_use_ = false;
310 return ret;
311 }
312 return false;
313 }
314
InsertRTCPPacket(const uint8_t * rtcp_packet,int rtcp_packet_length)315 int ViEReceiver::InsertRTCPPacket(const uint8_t* rtcp_packet,
316 int rtcp_packet_length) {
317 {
318 CriticalSectionScoped cs(receive_cs_.get());
319 if (!receiving_) {
320 return -1;
321 }
322
323 if (rtp_dump_) {
324 rtp_dump_->DumpPacket(
325 rtcp_packet, static_cast<uint16_t>(rtcp_packet_length));
326 }
327
328 std::list<RtpRtcp*>::iterator it = rtp_rtcp_simulcast_.begin();
329 while (it != rtp_rtcp_simulcast_.end()) {
330 RtpRtcp* rtp_rtcp = *it++;
331 rtp_rtcp->IncomingRtcpPacket(rtcp_packet, rtcp_packet_length);
332 }
333 }
334 assert(rtp_rtcp_); // Should be set by owner at construction time.
335 int ret = rtp_rtcp_->IncomingRtcpPacket(rtcp_packet, rtcp_packet_length);
336 if (ret != 0) {
337 return ret;
338 }
339
340 ntp_estimator_->UpdateRtcpTimestamp(rtp_receiver_->SSRC(), rtp_rtcp_);
341
342 return 0;
343 }
344
StartReceive()345 void ViEReceiver::StartReceive() {
346 CriticalSectionScoped cs(receive_cs_.get());
347 receiving_ = true;
348 }
349
StopReceive()350 void ViEReceiver::StopReceive() {
351 CriticalSectionScoped cs(receive_cs_.get());
352 receiving_ = false;
353 }
354
StartRTPDump(const char file_nameUTF8[1024])355 int ViEReceiver::StartRTPDump(const char file_nameUTF8[1024]) {
356 CriticalSectionScoped cs(receive_cs_.get());
357 if (rtp_dump_) {
358 // Restart it if it already exists and is started
359 rtp_dump_->Stop();
360 } else {
361 rtp_dump_ = RtpDump::CreateRtpDump();
362 if (rtp_dump_ == NULL) {
363 return -1;
364 }
365 }
366 if (rtp_dump_->Start(file_nameUTF8) != 0) {
367 RtpDump::DestroyRtpDump(rtp_dump_);
368 rtp_dump_ = NULL;
369 return -1;
370 }
371 return 0;
372 }
373
StopRTPDump()374 int ViEReceiver::StopRTPDump() {
375 CriticalSectionScoped cs(receive_cs_.get());
376 if (rtp_dump_) {
377 if (rtp_dump_->IsActive()) {
378 rtp_dump_->Stop();
379 }
380 RtpDump::DestroyRtpDump(rtp_dump_);
381 rtp_dump_ = NULL;
382 } else {
383 return -1;
384 }
385 return 0;
386 }
387
GetReceiveBandwidthEstimatorStats(ReceiveBandwidthEstimatorStats * output) const388 void ViEReceiver::GetReceiveBandwidthEstimatorStats(
389 ReceiveBandwidthEstimatorStats* output) const {
390 remote_bitrate_estimator_->GetStats(output);
391 }
392
GetReceiveStatistics() const393 ReceiveStatistics* ViEReceiver::GetReceiveStatistics() const {
394 return rtp_receive_statistics_.get();
395 }
396
IsPacketInOrder(const RTPHeader & header) const397 bool ViEReceiver::IsPacketInOrder(const RTPHeader& header) const {
398 StreamStatistician* statistician =
399 rtp_receive_statistics_->GetStatistician(header.ssrc);
400 if (!statistician)
401 return false;
402 return statistician->IsPacketInOrder(header.sequenceNumber);
403 }
404
IsPacketRetransmitted(const RTPHeader & header,bool in_order) const405 bool ViEReceiver::IsPacketRetransmitted(const RTPHeader& header,
406 bool in_order) const {
407 // Retransmissions are handled separately if RTX is enabled.
408 if (rtp_payload_registry_->RtxEnabled())
409 return false;
410 StreamStatistician* statistician =
411 rtp_receive_statistics_->GetStatistician(header.ssrc);
412 if (!statistician)
413 return false;
414 // Check if this is a retransmission.
415 uint16_t min_rtt = 0;
416 rtp_rtcp_->RTT(rtp_receiver_->SSRC(), NULL, NULL, &min_rtt, NULL);
417 return !in_order &&
418 statistician->IsRetransmitOfOldPacket(header, min_rtt);
419 }
420 } // namespace webrtc
421