| /* |
| * Copyright (c) 2012 The WebRTC project authors. All Rights Reserved. |
| * |
| * Use of this source code is governed by a BSD-style license |
| * that can be found in the LICENSE file in the root of the source |
| * tree. An additional intellectual property rights grant can be found |
| * in the file PATENTS. All contributing project authors may |
| * be found in the AUTHORS file in the root of the source tree. |
| */ |
| |
| #include "modules/rtp_rtcp/source/rtp_sender_video.h" |
| |
| #include <stdlib.h> |
| #include <string.h> |
| |
| #include <algorithm> |
| #include <limits> |
| #include <memory> |
| #include <string> |
| #include <utility> |
| |
| #include "absl/memory/memory.h" |
| #include "absl/strings/match.h" |
| #include "api/crypto/frame_encryptor_interface.h" |
| #include "api/transport/rtp/dependency_descriptor.h" |
| #include "modules/remote_bitrate_estimator/test/bwe_test_logging.h" |
| #include "modules/rtp_rtcp/include/rtp_rtcp_defines.h" |
| #include "modules/rtp_rtcp/source/absolute_capture_time_sender.h" |
| #include "modules/rtp_rtcp/source/byte_io.h" |
| #include "modules/rtp_rtcp/source/rtp_dependency_descriptor_extension.h" |
| #include "modules/rtp_rtcp/source/rtp_format.h" |
| #include "modules/rtp_rtcp/source/rtp_generic_frame_descriptor_extension.h" |
| #include "modules/rtp_rtcp/source/rtp_header_extensions.h" |
| #include "modules/rtp_rtcp/source/rtp_packet_to_send.h" |
| #include "modules/rtp_rtcp/source/time_util.h" |
| #include "rtc_base/checks.h" |
| #include "rtc_base/logging.h" |
| #include "rtc_base/trace_event.h" |
| |
| namespace webrtc { |
| |
| namespace { |
| constexpr size_t kRedForFecHeaderLength = 1; |
| constexpr int64_t kMaxUnretransmittableFrameIntervalMs = 33 * 4; |
| |
| // This is experimental field trial to exclude transport sequence number from |
| // FEC packets and should only be used in conjunction with datagram transport. |
| // Datagram transport removes transport sequence numbers from RTP packets and |
| // uses datagram feedback loop to re-generate RTCP feedback packets, but FEC |
| // contorol packets are calculated before sequence number is removed and as a |
| // result recovered packets will be corrupt unless we also remove transport |
| // sequence number during FEC calculation. |
| // |
| // TODO(sukhanov): We need to find find better way to implement FEC with |
| // datagram transport, probably moving FEC to datagram integration layter. We |
| // should also remove special field trial once we switch datagram path from |
| // RTCConfiguration flags to field trial and use the same field trial for FEC |
| // workaround. |
| const char kExcludeTransportSequenceNumberFromFecFieldTrial[] = |
| "WebRTC-ExcludeTransportSequenceNumberFromFec"; |
| |
| void BuildRedPayload(const RtpPacketToSend& media_packet, |
| RtpPacketToSend* red_packet) { |
| uint8_t* red_payload = red_packet->AllocatePayload( |
| kRedForFecHeaderLength + media_packet.payload_size()); |
| RTC_DCHECK(red_payload); |
| red_payload[0] = media_packet.PayloadType(); |
| |
| auto media_payload = media_packet.payload(); |
| memcpy(&red_payload[kRedForFecHeaderLength], media_payload.data(), |
| media_payload.size()); |
| } |
| |
| void AddRtpHeaderExtensions( |
| const RTPVideoHeader& video_header, |
| const absl::optional<PlayoutDelay>& playout_delay, |
| const absl::optional<AbsoluteCaptureTime>& absolute_capture_time, |
| FrameDependencyStructure* video_structure, |
| bool set_video_rotation, |
| bool set_color_space, |
| bool set_frame_marking, |
| bool first_packet, |
| bool last_packet, |
| RtpPacketToSend* packet) { |
| // Color space requires two-byte header extensions if HDR metadata is |
| // included. Therefore, it's best to add this extension first so that the |
| // other extensions in the same packet are written as two-byte headers at |
| // once. |
| if (last_packet && set_color_space && video_header.color_space) |
| packet->SetExtension<ColorSpaceExtension>(video_header.color_space.value()); |
| |
| if (last_packet && set_video_rotation) |
| packet->SetExtension<VideoOrientation>(video_header.rotation); |
| |
| // Report content type only for key frames. |
| if (last_packet && |
| video_header.frame_type == VideoFrameType::kVideoFrameKey && |
| video_header.content_type != VideoContentType::UNSPECIFIED) |
| packet->SetExtension<VideoContentTypeExtension>(video_header.content_type); |
| |
| if (last_packet && |
| video_header.video_timing.flags != VideoSendTiming::kInvalid) |
| packet->SetExtension<VideoTimingExtension>(video_header.video_timing); |
| |
| // If transmitted, add to all packets; ack logic depends on this. |
| if (playout_delay) { |
| packet->SetExtension<PlayoutDelayLimits>(*playout_delay); |
| } |
| |
| if (first_packet && absolute_capture_time) { |
| packet->SetExtension<AbsoluteCaptureTimeExtension>(*absolute_capture_time); |
| } |
| |
| if (set_frame_marking) { |
| FrameMarking frame_marking = video_header.frame_marking; |
| frame_marking.start_of_frame = first_packet; |
| frame_marking.end_of_frame = last_packet; |
| packet->SetExtension<FrameMarkingExtension>(frame_marking); |
| } |
| |
| if (video_header.generic) { |
| bool extension_is_set = false; |
| if (video_structure != nullptr) { |
| DependencyDescriptor descriptor; |
| descriptor.first_packet_in_frame = first_packet; |
| descriptor.last_packet_in_frame = last_packet; |
| descriptor.frame_number = video_header.generic->frame_id & 0xFFFF; |
| descriptor.frame_dependencies.spatial_id = |
| video_header.generic->spatial_index; |
| descriptor.frame_dependencies.temporal_id = |
| video_header.generic->temporal_index; |
| for (int64_t dep : video_header.generic->dependencies) { |
| descriptor.frame_dependencies.frame_diffs.push_back( |
| video_header.generic->frame_id - dep); |
| } |
| descriptor.frame_dependencies.decode_target_indications = |
| video_header.generic->decode_target_indications; |
| RTC_DCHECK_EQ( |
| descriptor.frame_dependencies.decode_target_indications.size(), |
| video_structure->num_decode_targets); |
| |
| // To avoid extra structure copy, temporary share ownership of the |
| // video_structure with the dependency descriptor. |
| if (video_header.frame_type == VideoFrameType::kVideoFrameKey && |
| first_packet) { |
| descriptor.attached_structure = absl::WrapUnique(video_structure); |
| } |
| extension_is_set = packet->SetExtension<RtpDependencyDescriptorExtension>( |
| *video_structure, descriptor); |
| |
| // Remove the temporary shared ownership. |
| descriptor.attached_structure.release(); |
| } |
| |
| // Do not use v0/v1 generic frame descriptor when v2 is stored. |
| if (!extension_is_set) { |
| RtpGenericFrameDescriptor generic_descriptor; |
| generic_descriptor.SetFirstPacketInSubFrame(first_packet); |
| generic_descriptor.SetLastPacketInSubFrame(last_packet); |
| generic_descriptor.SetDiscardable(video_header.generic->discardable); |
| |
| if (first_packet) { |
| generic_descriptor.SetFrameId( |
| static_cast<uint16_t>(video_header.generic->frame_id)); |
| for (int64_t dep : video_header.generic->dependencies) { |
| generic_descriptor.AddFrameDependencyDiff( |
| video_header.generic->frame_id - dep); |
| } |
| |
| uint8_t spatial_bimask = 1 << video_header.generic->spatial_index; |
| generic_descriptor.SetSpatialLayersBitmask(spatial_bimask); |
| |
| generic_descriptor.SetTemporalLayer( |
| video_header.generic->temporal_index); |
| |
| if (video_header.frame_type == VideoFrameType::kVideoFrameKey) { |
| generic_descriptor.SetResolution(video_header.width, |
| video_header.height); |
| } |
| } |
| |
| if (!packet->SetExtension<RtpGenericFrameDescriptorExtension01>( |
| generic_descriptor)) { |
| packet->SetExtension<RtpGenericFrameDescriptorExtension00>( |
| generic_descriptor); |
| } |
| } |
| } |
| } |
| |
| bool MinimizeDescriptor(RTPVideoHeader* video_header) { |
| if (auto* vp8 = |
| absl::get_if<RTPVideoHeaderVP8>(&video_header->video_type_header)) { |
| // Set minimum fields the RtpPacketizer is using to create vp8 packets. |
| // nonReference is the only field that doesn't require extra space. |
| bool non_reference = vp8->nonReference; |
| vp8->InitRTPVideoHeaderVP8(); |
| vp8->nonReference = non_reference; |
| return true; |
| } |
| // TODO(danilchap): Reduce vp9 codec specific descriptor too. |
| return false; |
| } |
| |
| bool IsBaseLayer(const RTPVideoHeader& video_header) { |
| switch (video_header.codec) { |
| case kVideoCodecVP8: { |
| const auto& vp8 = |
| absl::get<RTPVideoHeaderVP8>(video_header.video_type_header); |
| return (vp8.temporalIdx == 0 || vp8.temporalIdx == kNoTemporalIdx); |
| } |
| case kVideoCodecVP9: { |
| const auto& vp9 = |
| absl::get<RTPVideoHeaderVP9>(video_header.video_type_header); |
| return (vp9.temporal_idx == 0 || vp9.temporal_idx == kNoTemporalIdx); |
| } |
| case kVideoCodecH264: |
| // TODO(kron): Implement logic for H264 once WebRTC supports temporal |
| // layers for H264. |
| break; |
| default: |
| break; |
| } |
| return true; |
| } |
| |
| #if RTC_TRACE_EVENTS_ENABLED |
| const char* FrameTypeToString(VideoFrameType frame_type) { |
| switch (frame_type) { |
| case VideoFrameType::kEmptyFrame: |
| return "empty"; |
| case VideoFrameType::kVideoFrameKey: |
| return "video_key"; |
| case VideoFrameType::kVideoFrameDelta: |
| return "video_delta"; |
| default: |
| RTC_NOTREACHED(); |
| return ""; |
| } |
| } |
| #endif |
| |
| bool IsNoopDelay(const PlayoutDelay& delay) { |
| return delay.min_ms == -1 && delay.max_ms == -1; |
| } |
| |
| } // namespace |
| |
| RTPSenderVideo::RTPSenderVideo(const Config& config) |
| : rtp_sender_(config.rtp_sender), |
| clock_(config.clock), |
| retransmission_settings_( |
| config.enable_retransmit_all_layers |
| ? kRetransmitAllLayers |
| : (kRetransmitBaseLayer | kConditionallyRetransmitHigherLayers)), |
| last_rotation_(kVideoRotation_0), |
| transmit_color_space_next_frame_(false), |
| current_playout_delay_{-1, -1}, |
| playout_delay_pending_(false), |
| red_payload_type_(config.red_payload_type), |
| ulpfec_payload_type_(config.ulpfec_payload_type), |
| flexfec_sender_(config.flexfec_sender), |
| delta_fec_params_{0, 1, kFecMaskRandom}, |
| key_fec_params_{0, 1, kFecMaskRandom}, |
| fec_bitrate_(1000, RateStatistics::kBpsScale), |
| video_bitrate_(1000, RateStatistics::kBpsScale), |
| packetization_overhead_bitrate_(1000, RateStatistics::kBpsScale), |
| frame_encryptor_(config.frame_encryptor), |
| require_frame_encryption_(config.require_frame_encryption), |
| generic_descriptor_auth_experiment_( |
| config.field_trials->Lookup("WebRTC-GenericDescriptorAuth") |
| .find("Enabled") == 0), |
| exclude_transport_sequence_number_from_fec_experiment_( |
| config.field_trials |
| ->Lookup(kExcludeTransportSequenceNumberFromFecFieldTrial) |
| .find("Enabled") == 0), |
| absolute_capture_time_sender_(config.clock) {} |
| |
| RTPSenderVideo::~RTPSenderVideo() {} |
| |
| void RTPSenderVideo::AppendAsRedMaybeWithUlpfec( |
| std::unique_ptr<RtpPacketToSend> media_packet, |
| bool protect_media_packet, |
| std::vector<std::unique_ptr<RtpPacketToSend>>* packets) { |
| std::unique_ptr<RtpPacketToSend> red_packet( |
| new RtpPacketToSend(*media_packet)); |
| BuildRedPayload(*media_packet, red_packet.get()); |
| red_packet->SetPayloadType(*red_payload_type_); |
| |
| std::vector<std::unique_ptr<RedPacket>> fec_packets; |
| if (ulpfec_enabled()) { |
| if (protect_media_packet) { |
| if (exclude_transport_sequence_number_from_fec_experiment_) { |
| // See comments at the top of the file why experiment |
| // "WebRTC-kExcludeTransportSequenceNumberFromFec" is needed in |
| // conjunction with datagram transport. |
| // TODO(sukhanov): We may also need to implement it for flexfec_sender |
| // if we decide to keep this approach in the future. |
| uint16_t transport_senquence_number; |
| if (media_packet->GetExtension<webrtc::TransportSequenceNumber>( |
| &transport_senquence_number)) { |
| if (!media_packet->RemoveExtension( |
| webrtc::TransportSequenceNumber::kId)) { |
| RTC_NOTREACHED() |
| << "Failed to remove transport sequence number, packet=" |
| << media_packet->ToString(); |
| } |
| } |
| } |
| |
| ulpfec_generator_.AddRtpPacketAndGenerateFec( |
| media_packet->Buffer(), media_packet->headers_size()); |
| } |
| uint16_t num_fec_packets = ulpfec_generator_.NumAvailableFecPackets(); |
| if (num_fec_packets > 0) { |
| uint16_t first_fec_sequence_number = |
| rtp_sender_->AllocateSequenceNumber(num_fec_packets); |
| fec_packets = ulpfec_generator_.GetUlpfecPacketsAsRed( |
| *red_payload_type_, *ulpfec_payload_type_, first_fec_sequence_number); |
| RTC_DCHECK_EQ(num_fec_packets, fec_packets.size()); |
| } |
| } |
| |
| // Send |red_packet| instead of |packet| for allocated sequence number. |
| red_packet->set_packet_type(RtpPacketMediaType::kVideo); |
| red_packet->set_allow_retransmission(media_packet->allow_retransmission()); |
| packets->emplace_back(std::move(red_packet)); |
| |
| for (const auto& fec_packet : fec_packets) { |
| // TODO(danilchap): Make ulpfec_generator_ generate RtpPacketToSend to avoid |
| // reparsing them. |
| std::unique_ptr<RtpPacketToSend> rtp_packet( |
| new RtpPacketToSend(*media_packet)); |
| RTC_CHECK(rtp_packet->Parse(fec_packet->data(), fec_packet->length())); |
| rtp_packet->set_capture_time_ms(media_packet->capture_time_ms()); |
| rtp_packet->set_packet_type(RtpPacketMediaType::kForwardErrorCorrection); |
| rtp_packet->set_allow_retransmission(false); |
| RTC_DCHECK_EQ(fec_packet->length(), rtp_packet->size()); |
| packets->emplace_back(std::move(rtp_packet)); |
| } |
| } |
| |
| void RTPSenderVideo::GenerateAndAppendFlexfec( |
| std::vector<std::unique_ptr<RtpPacketToSend>>* packets) { |
| RTC_DCHECK(flexfec_sender_); |
| |
| if (flexfec_sender_->FecAvailable()) { |
| std::vector<std::unique_ptr<RtpPacketToSend>> fec_packets = |
| flexfec_sender_->GetFecPackets(); |
| for (auto& fec_packet : fec_packets) { |
| fec_packet->set_packet_type(RtpPacketMediaType::kForwardErrorCorrection); |
| fec_packet->set_allow_retransmission(false); |
| packets->emplace_back(std::move(fec_packet)); |
| } |
| } |
| } |
| |
| void RTPSenderVideo::LogAndSendToNetwork( |
| std::vector<std::unique_ptr<RtpPacketToSend>> packets, |
| size_t unpacketized_payload_size) { |
| int64_t now_ms = clock_->TimeInMilliseconds(); |
| #if BWE_TEST_LOGGING_COMPILE_TIME_ENABLE |
| for (const auto& packet : packets) { |
| if (packet->packet_type() == RtpPacketMediaType::kForwardErrorCorrection) { |
| const uint32_t ssrc = packet->Ssrc(); |
| BWE_TEST_LOGGING_PLOT_WITH_SSRC(1, "VideoFecBitrate_kbps", now_ms, |
| FecOverheadRate() / 1000, ssrc); |
| } |
| } |
| #endif |
| |
| { |
| rtc::CritScope cs(&stats_crit_); |
| size_t packetized_payload_size = 0; |
| for (const auto& packet : packets) { |
| switch (*packet->packet_type()) { |
| case RtpPacketMediaType::kVideo: |
| video_bitrate_.Update(packet->size(), now_ms); |
| packetized_payload_size += packet->payload_size(); |
| break; |
| case RtpPacketMediaType::kForwardErrorCorrection: |
| fec_bitrate_.Update(packet->size(), clock_->TimeInMilliseconds()); |
| break; |
| default: |
| continue; |
| } |
| } |
| // AV1 packetizer may produce less packetized bytes than unpacketized. |
| if (packetized_payload_size >= unpacketized_payload_size) { |
| packetization_overhead_bitrate_.Update( |
| packetized_payload_size - unpacketized_payload_size, |
| clock_->TimeInMilliseconds()); |
| } |
| } |
| |
| rtp_sender_->EnqueuePackets(std::move(packets)); |
| } |
| |
| size_t RTPSenderVideo::FecPacketOverhead() const { |
| if (flexfec_enabled()) |
| return flexfec_sender_->MaxPacketOverhead(); |
| |
| size_t overhead = 0; |
| if (red_enabled()) { |
| // The RED overhead is due to a small header. |
| overhead += kRedForFecHeaderLength; |
| } |
| if (ulpfec_enabled()) { |
| // For ULPFEC, the overhead is the FEC headers plus RED for FEC header |
| // (see above) plus anything in RTP header beyond the 12 bytes base header |
| // (CSRC list, extensions...) |
| // This reason for the header extensions to be included here is that |
| // from an FEC viewpoint, they are part of the payload to be protected. |
| // (The base RTP header is already protected by the FEC header.) |
| overhead += ulpfec_generator_.MaxPacketOverhead() + |
| (rtp_sender_->RtpHeaderLength() - kRtpHeaderSize); |
| } |
| return overhead; |
| } |
| |
| void RTPSenderVideo::SetFecParameters(const FecProtectionParams& delta_params, |
| const FecProtectionParams& key_params) { |
| rtc::CritScope cs(&crit_); |
| delta_fec_params_ = delta_params; |
| key_fec_params_ = key_params; |
| } |
| |
| absl::optional<uint32_t> RTPSenderVideo::FlexfecSsrc() const { |
| if (flexfec_sender_) { |
| return flexfec_sender_->ssrc(); |
| } |
| return absl::nullopt; |
| } |
| |
| void RTPSenderVideo::SetVideoStructure( |
| const FrameDependencyStructure* video_structure) { |
| RTC_DCHECK_RUNS_SERIALIZED(&send_checker_); |
| if (video_structure == nullptr) { |
| video_structure_ = nullptr; |
| return; |
| } |
| // Simple sanity checks video structure is set up. |
| RTC_DCHECK_GT(video_structure->num_decode_targets, 0); |
| RTC_DCHECK_GT(video_structure->templates.size(), 0); |
| |
| int structure_id = 0; |
| if (video_structure_) { |
| if (*video_structure_ == *video_structure) { |
| // Same structure (just a new key frame), no update required. |
| return; |
| } |
| // When setting different video structure make sure structure_id is updated |
| // so that templates from different structures do not collide. |
| static constexpr int kMaxTemplates = 64; |
| structure_id = |
| (video_structure_->structure_id + video_structure_->templates.size()) % |
| kMaxTemplates; |
| } |
| |
| video_structure_ = |
| std::make_unique<FrameDependencyStructure>(*video_structure); |
| video_structure_->structure_id = structure_id; |
| // TODO(bugs.webrtc.org/10342): Support chains. |
| video_structure_->num_chains = 0; |
| } |
| |
| bool RTPSenderVideo::SendVideo( |
| int payload_type, |
| absl::optional<VideoCodecType> codec_type, |
| uint32_t rtp_timestamp, |
| int64_t capture_time_ms, |
| rtc::ArrayView<const uint8_t> payload, |
| const RTPFragmentationHeader* fragmentation, |
| RTPVideoHeader video_header, |
| absl::optional<int64_t> expected_retransmission_time_ms) { |
| #if RTC_TRACE_EVENTS_ENABLED |
| TRACE_EVENT_ASYNC_STEP1("webrtc", "Video", capture_time_ms, "Send", "type", |
| FrameTypeToString(video_header.frame_type)); |
| #endif |
| RTC_CHECK_RUNS_SERIALIZED(&send_checker_); |
| |
| if (video_header.frame_type == VideoFrameType::kEmptyFrame) |
| return true; |
| |
| if (payload.empty()) |
| return false; |
| |
| int32_t retransmission_settings = retransmission_settings_; |
| if (codec_type == VideoCodecType::kVideoCodecH264) { |
| // Backward compatibility for older receivers without temporal layer logic. |
| retransmission_settings = kRetransmitBaseLayer | kRetransmitHigherLayers; |
| } |
| |
| bool set_frame_marking = |
| video_header.codec == kVideoCodecH264 && |
| video_header.frame_marking.temporal_id != kNoTemporalIdx; |
| |
| MaybeUpdateCurrentPlayoutDelay(video_header); |
| if (video_header.frame_type == VideoFrameType::kVideoFrameKey && |
| !IsNoopDelay(current_playout_delay_)) { |
| // Force playout delay on key-frames, if set. |
| playout_delay_pending_ = true; |
| } |
| const absl::optional<PlayoutDelay> playout_delay = |
| playout_delay_pending_ |
| ? absl::optional<PlayoutDelay>(current_playout_delay_) |
| : absl::nullopt; |
| |
| // According to |
| // http://www.etsi.org/deliver/etsi_ts/126100_126199/126114/12.07.00_60/ |
| // ts_126114v120700p.pdf Section 7.4.5: |
| // The MTSI client shall add the payload bytes as defined in this clause |
| // onto the last RTP packet in each group of packets which make up a key |
| // frame (I-frame or IDR frame in H.264 (AVC), or an IRAP picture in H.265 |
| // (HEVC)). The MTSI client may also add the payload bytes onto the last RTP |
| // packet in each group of packets which make up another type of frame |
| // (e.g. a P-Frame) only if the current value is different from the previous |
| // value sent. |
| // Set rotation when key frame or when changed (to follow standard). |
| // Or when different from 0 (to follow current receiver implementation). |
| bool set_video_rotation = |
| video_header.frame_type == VideoFrameType::kVideoFrameKey || |
| video_header.rotation != last_rotation_ || |
| video_header.rotation != kVideoRotation_0; |
| last_rotation_ = video_header.rotation; |
| |
| // Send color space when changed or if the frame is a key frame. Keep |
| // sending color space information until the first base layer frame to |
| // guarantee that the information is retrieved by the receiver. |
| bool set_color_space; |
| if (video_header.color_space != last_color_space_) { |
| last_color_space_ = video_header.color_space; |
| set_color_space = true; |
| transmit_color_space_next_frame_ = !IsBaseLayer(video_header); |
| } else { |
| set_color_space = |
| video_header.frame_type == VideoFrameType::kVideoFrameKey || |
| transmit_color_space_next_frame_; |
| transmit_color_space_next_frame_ = |
| transmit_color_space_next_frame_ ? !IsBaseLayer(video_header) : false; |
| } |
| |
| if (flexfec_enabled() || ulpfec_enabled()) { |
| rtc::CritScope cs(&crit_); |
| // FEC settings. |
| const FecProtectionParams& fec_params = |
| video_header.frame_type == VideoFrameType::kVideoFrameKey |
| ? key_fec_params_ |
| : delta_fec_params_; |
| if (flexfec_enabled()) |
| flexfec_sender_->SetFecParameters(fec_params); |
| if (ulpfec_enabled()) |
| ulpfec_generator_.SetFecParameters(fec_params); |
| } |
| |
| // Maximum size of packet including rtp headers. |
| // Extra space left in case packet will be resent using fec or rtx. |
| int packet_capacity = rtp_sender_->MaxRtpPacketSize() - FecPacketOverhead() - |
| (rtp_sender_->RtxStatus() ? kRtxHeaderSize : 0); |
| |
| std::unique_ptr<RtpPacketToSend> single_packet = |
| rtp_sender_->AllocatePacket(); |
| RTC_DCHECK_LE(packet_capacity, single_packet->capacity()); |
| single_packet->SetPayloadType(payload_type); |
| single_packet->SetTimestamp(rtp_timestamp); |
| single_packet->set_capture_time_ms(capture_time_ms); |
| |
| const absl::optional<AbsoluteCaptureTime> absolute_capture_time = |
| absolute_capture_time_sender_.OnSendPacket( |
| AbsoluteCaptureTimeSender::GetSource(single_packet->Ssrc(), |
| single_packet->Csrcs()), |
| single_packet->Timestamp(), kVideoPayloadTypeFrequency, |
| Int64MsToUQ32x32(single_packet->capture_time_ms() + NtpOffsetMs()), |
| /*estimated_capture_clock_offset=*/absl::nullopt); |
| |
| auto first_packet = std::make_unique<RtpPacketToSend>(*single_packet); |
| auto middle_packet = std::make_unique<RtpPacketToSend>(*single_packet); |
| auto last_packet = std::make_unique<RtpPacketToSend>(*single_packet); |
| // Simplest way to estimate how much extensions would occupy is to set them. |
| AddRtpHeaderExtensions(video_header, playout_delay, absolute_capture_time, |
| video_structure_.get(), set_video_rotation, |
| set_color_space, set_frame_marking, |
| /*first=*/true, /*last=*/true, single_packet.get()); |
| AddRtpHeaderExtensions(video_header, playout_delay, absolute_capture_time, |
| video_structure_.get(), set_video_rotation, |
| set_color_space, set_frame_marking, |
| /*first=*/true, /*last=*/false, first_packet.get()); |
| AddRtpHeaderExtensions(video_header, playout_delay, absolute_capture_time, |
| video_structure_.get(), set_video_rotation, |
| set_color_space, set_frame_marking, |
| /*first=*/false, /*last=*/false, middle_packet.get()); |
| AddRtpHeaderExtensions(video_header, playout_delay, absolute_capture_time, |
| video_structure_.get(), set_video_rotation, |
| set_color_space, set_frame_marking, |
| /*first=*/false, /*last=*/true, last_packet.get()); |
| |
| RTC_DCHECK_GT(packet_capacity, single_packet->headers_size()); |
| RTC_DCHECK_GT(packet_capacity, first_packet->headers_size()); |
| RTC_DCHECK_GT(packet_capacity, middle_packet->headers_size()); |
| RTC_DCHECK_GT(packet_capacity, last_packet->headers_size()); |
| RtpPacketizer::PayloadSizeLimits limits; |
| limits.max_payload_len = packet_capacity - middle_packet->headers_size(); |
| |
| RTC_DCHECK_GE(single_packet->headers_size(), middle_packet->headers_size()); |
| limits.single_packet_reduction_len = |
| single_packet->headers_size() - middle_packet->headers_size(); |
| |
| RTC_DCHECK_GE(first_packet->headers_size(), middle_packet->headers_size()); |
| limits.first_packet_reduction_len = |
| first_packet->headers_size() - middle_packet->headers_size(); |
| |
| RTC_DCHECK_GE(last_packet->headers_size(), middle_packet->headers_size()); |
| limits.last_packet_reduction_len = |
| last_packet->headers_size() - middle_packet->headers_size(); |
| |
| rtc::ArrayView<const uint8_t> generic_descriptor_raw_00 = |
| first_packet->GetRawExtension<RtpGenericFrameDescriptorExtension00>(); |
| rtc::ArrayView<const uint8_t> generic_descriptor_raw_01 = |
| first_packet->GetRawExtension<RtpGenericFrameDescriptorExtension01>(); |
| |
| if (!generic_descriptor_raw_00.empty() && |
| !generic_descriptor_raw_01.empty()) { |
| RTC_LOG(LS_WARNING) << "Two versions of GFD extension used."; |
| return false; |
| } |
| |
| // Minimiazation of the vp8 descriptor may erase temporal_id, so save it. |
| const uint8_t temporal_id = GetTemporalId(video_header); |
| rtc::ArrayView<const uint8_t> generic_descriptor_raw = |
| !generic_descriptor_raw_01.empty() ? generic_descriptor_raw_01 |
| : generic_descriptor_raw_00; |
| if (!generic_descriptor_raw.empty()) { |
| MinimizeDescriptor(&video_header); |
| } |
| |
| if (video_header.frame_type == VideoFrameType::kVideoFrameKey || |
| (IsBaseLayer(video_header) && |
| !(video_header.generic.has_value() ? video_header.generic->discardable |
| : false))) { |
| // This frame has guaranteed delivery, no need to populate playout |
| // delay extensions until it changes again. |
| playout_delay_pending_ = false; |
| } |
| |
| // TODO(benwright@webrtc.org) - Allocate enough to always encrypt inline. |
| rtc::Buffer encrypted_video_payload; |
| if (frame_encryptor_ != nullptr) { |
| if (generic_descriptor_raw.empty()) { |
| return false; |
| } |
| |
| const size_t max_ciphertext_size = |
| frame_encryptor_->GetMaxCiphertextByteSize(cricket::MEDIA_TYPE_VIDEO, |
| payload.size()); |
| encrypted_video_payload.SetSize(max_ciphertext_size); |
| |
| size_t bytes_written = 0; |
| |
| // Only enable header authentication if the field trial is enabled. |
| rtc::ArrayView<const uint8_t> additional_data; |
| if (generic_descriptor_auth_experiment_) { |
| additional_data = generic_descriptor_raw; |
| } |
| |
| if (frame_encryptor_->Encrypt( |
| cricket::MEDIA_TYPE_VIDEO, first_packet->Ssrc(), additional_data, |
| payload, encrypted_video_payload, &bytes_written) != 0) { |
| return false; |
| } |
| |
| encrypted_video_payload.SetSize(bytes_written); |
| payload = encrypted_video_payload; |
| } else if (require_frame_encryption_) { |
| RTC_LOG(LS_WARNING) |
| << "No FrameEncryptor is attached to this video sending stream but " |
| "one is required since require_frame_encryptor is set"; |
| } |
| |
| std::unique_ptr<RtpPacketizer> packetizer = RtpPacketizer::Create( |
| codec_type, payload, limits, video_header, fragmentation); |
| |
| // TODO(bugs.webrtc.org/10714): retransmission_settings_ should generally be |
| // replaced by expected_retransmission_time_ms.has_value(). For now, though, |
| // only VP8 with an injected frame buffer controller actually controls it. |
| const bool allow_retransmission = |
| expected_retransmission_time_ms.has_value() |
| ? AllowRetransmission(temporal_id, retransmission_settings, |
| expected_retransmission_time_ms.value()) |
| : false; |
| const size_t num_packets = packetizer->NumPackets(); |
| |
| size_t unpacketized_payload_size; |
| if (fragmentation && fragmentation->fragmentationVectorSize > 0) { |
| unpacketized_payload_size = 0; |
| for (uint16_t i = 0; i < fragmentation->fragmentationVectorSize; ++i) { |
| unpacketized_payload_size += fragmentation->fragmentationLength[i]; |
| } |
| } else { |
| unpacketized_payload_size = payload.size(); |
| } |
| |
| if (num_packets == 0) |
| return false; |
| |
| bool first_frame = first_frame_sent_(); |
| std::vector<std::unique_ptr<RtpPacketToSend>> rtp_packets; |
| for (size_t i = 0; i < num_packets; ++i) { |
| std::unique_ptr<RtpPacketToSend> packet; |
| int expected_payload_capacity; |
| // Choose right packet template: |
| if (num_packets == 1) { |
| packet = std::move(single_packet); |
| expected_payload_capacity = |
| limits.max_payload_len - limits.single_packet_reduction_len; |
| } else if (i == 0) { |
| packet = std::move(first_packet); |
| expected_payload_capacity = |
| limits.max_payload_len - limits.first_packet_reduction_len; |
| } else if (i == num_packets - 1) { |
| packet = std::move(last_packet); |
| expected_payload_capacity = |
| limits.max_payload_len - limits.last_packet_reduction_len; |
| } else { |
| packet = std::make_unique<RtpPacketToSend>(*middle_packet); |
| expected_payload_capacity = limits.max_payload_len; |
| } |
| |
| packet->set_first_packet_of_frame(i == 0); |
| |
| if (!packetizer->NextPacket(packet.get())) |
| return false; |
| RTC_DCHECK_LE(packet->payload_size(), expected_payload_capacity); |
| if (!rtp_sender_->AssignSequenceNumber(packet.get())) |
| return false; |
| |
| // No FEC protection for upper temporal layers, if used. |
| bool protect_packet = temporal_id == 0 || temporal_id == kNoTemporalIdx; |
| |
| packet->set_allow_retransmission(allow_retransmission); |
| |
| // Put packetization finish timestamp into extension. |
| if (packet->HasExtension<VideoTimingExtension>()) { |
| packet->set_packetization_finish_time_ms(clock_->TimeInMilliseconds()); |
| } |
| |
| if (red_enabled()) { |
| AppendAsRedMaybeWithUlpfec(std::move(packet), protect_packet, |
| &rtp_packets); |
| } else { |
| packet->set_packet_type(RtpPacketMediaType::kVideo); |
| const RtpPacketToSend& media_packet = *packet; |
| rtp_packets.emplace_back(std::move(packet)); |
| if (flexfec_enabled()) { |
| // TODO(brandtr): Remove the FlexFEC code path when FlexfecSender |
| // is wired up to PacedSender instead. |
| if (protect_packet) { |
| flexfec_sender_->AddRtpPacketAndGenerateFec(media_packet); |
| } |
| GenerateAndAppendFlexfec(&rtp_packets); |
| } |
| } |
| |
| if (first_frame) { |
| if (i == 0) { |
| RTC_LOG(LS_INFO) |
| << "Sent first RTP packet of the first video frame (pre-pacer)"; |
| } |
| if (i == num_packets - 1) { |
| RTC_LOG(LS_INFO) |
| << "Sent last RTP packet of the first video frame (pre-pacer)"; |
| } |
| } |
| } |
| |
| LogAndSendToNetwork(std::move(rtp_packets), unpacketized_payload_size); |
| |
| TRACE_EVENT_ASYNC_END1("webrtc", "Video", capture_time_ms, "timestamp", |
| rtp_timestamp); |
| return true; |
| } |
| |
| uint32_t RTPSenderVideo::VideoBitrateSent() const { |
| rtc::CritScope cs(&stats_crit_); |
| return video_bitrate_.Rate(clock_->TimeInMilliseconds()).value_or(0); |
| } |
| |
| uint32_t RTPSenderVideo::FecOverheadRate() const { |
| rtc::CritScope cs(&stats_crit_); |
| return fec_bitrate_.Rate(clock_->TimeInMilliseconds()).value_or(0); |
| } |
| |
| uint32_t RTPSenderVideo::PacketizationOverheadBps() const { |
| rtc::CritScope cs(&stats_crit_); |
| return packetization_overhead_bitrate_.Rate(clock_->TimeInMilliseconds()) |
| .value_or(0); |
| } |
| |
| bool RTPSenderVideo::AllowRetransmission( |
| uint8_t temporal_id, |
| int32_t retransmission_settings, |
| int64_t expected_retransmission_time_ms) { |
| if (retransmission_settings == kRetransmitOff) |
| return false; |
| |
| rtc::CritScope cs(&stats_crit_); |
| // Media packet storage. |
| if ((retransmission_settings & kConditionallyRetransmitHigherLayers) && |
| UpdateConditionalRetransmit(temporal_id, |
| expected_retransmission_time_ms)) { |
| retransmission_settings |= kRetransmitHigherLayers; |
| } |
| |
| if (temporal_id == kNoTemporalIdx) |
| return true; |
| |
| if ((retransmission_settings & kRetransmitBaseLayer) && temporal_id == 0) |
| return true; |
| |
| if ((retransmission_settings & kRetransmitHigherLayers) && temporal_id > 0) |
| return true; |
| |
| return false; |
| } |
| |
| uint8_t RTPSenderVideo::GetTemporalId(const RTPVideoHeader& header) { |
| struct TemporalIdGetter { |
| uint8_t operator()(const RTPVideoHeaderVP8& vp8) { return vp8.temporalIdx; } |
| uint8_t operator()(const RTPVideoHeaderVP9& vp9) { |
| return vp9.temporal_idx; |
| } |
| uint8_t operator()(const RTPVideoHeaderH264&) { return kNoTemporalIdx; } |
| uint8_t operator()(const RTPVideoHeaderLegacyGeneric&) { |
| return kNoTemporalIdx; |
| } |
| uint8_t operator()(const absl::monostate&) { return kNoTemporalIdx; } |
| }; |
| switch (header.codec) { |
| case kVideoCodecH264: |
| return header.frame_marking.temporal_id; |
| default: |
| return absl::visit(TemporalIdGetter(), header.video_type_header); |
| } |
| } |
| |
| bool RTPSenderVideo::UpdateConditionalRetransmit( |
| uint8_t temporal_id, |
| int64_t expected_retransmission_time_ms) { |
| int64_t now_ms = clock_->TimeInMilliseconds(); |
| // Update stats for any temporal layer. |
| TemporalLayerStats* current_layer_stats = |
| &frame_stats_by_temporal_layer_[temporal_id]; |
| current_layer_stats->frame_rate_fp1000s.Update(1, now_ms); |
| int64_t tl_frame_interval = now_ms - current_layer_stats->last_frame_time_ms; |
| current_layer_stats->last_frame_time_ms = now_ms; |
| |
| // Conditional retransmit only applies to upper layers. |
| if (temporal_id != kNoTemporalIdx && temporal_id > 0) { |
| if (tl_frame_interval >= kMaxUnretransmittableFrameIntervalMs) { |
| // Too long since a retransmittable frame in this layer, enable NACK |
| // protection. |
| return true; |
| } else { |
| // Estimate when the next frame of any lower layer will be sent. |
| const int64_t kUndefined = std::numeric_limits<int64_t>::max(); |
| int64_t expected_next_frame_time = kUndefined; |
| for (int i = temporal_id - 1; i >= 0; --i) { |
| TemporalLayerStats* stats = &frame_stats_by_temporal_layer_[i]; |
| absl::optional<uint32_t> rate = stats->frame_rate_fp1000s.Rate(now_ms); |
| if (rate) { |
| int64_t tl_next = stats->last_frame_time_ms + 1000000 / *rate; |
| if (tl_next - now_ms > -expected_retransmission_time_ms && |
| tl_next < expected_next_frame_time) { |
| expected_next_frame_time = tl_next; |
| } |
| } |
| } |
| |
| if (expected_next_frame_time == kUndefined || |
| expected_next_frame_time - now_ms > expected_retransmission_time_ms) { |
| // The next frame in a lower layer is expected at a later time (or |
| // unable to tell due to lack of data) than a retransmission is |
| // estimated to be able to arrive, so allow this packet to be nacked. |
| return true; |
| } |
| } |
| } |
| |
| return false; |
| } |
| |
| void RTPSenderVideo::MaybeUpdateCurrentPlayoutDelay( |
| const RTPVideoHeader& header) { |
| if (IsNoopDelay(header.playout_delay)) { |
| return; |
| } |
| |
| PlayoutDelay requested_delay = header.playout_delay; |
| |
| if (requested_delay.min_ms > PlayoutDelayLimits::kMaxMs || |
| requested_delay.max_ms > PlayoutDelayLimits::kMaxMs) { |
| RTC_DLOG(LS_ERROR) |
| << "Requested playout delay values out of range, ignored"; |
| return; |
| } |
| if (requested_delay.max_ms != -1 && |
| requested_delay.min_ms > requested_delay.max_ms) { |
| RTC_DLOG(LS_ERROR) << "Requested playout delay values out of order"; |
| return; |
| } |
| |
| if (!playout_delay_pending_) { |
| current_playout_delay_ = requested_delay; |
| playout_delay_pending_ = true; |
| return; |
| } |
| |
| if ((requested_delay.min_ms == -1 || |
| requested_delay.min_ms == current_playout_delay_.min_ms) && |
| (requested_delay.max_ms == -1 || |
| requested_delay.max_ms == current_playout_delay_.max_ms)) { |
| // No change, ignore. |
| return; |
| } |
| |
| if (requested_delay.min_ms == -1) { |
| RTC_DCHECK_GE(requested_delay.max_ms, 0); |
| requested_delay.min_ms = |
| std::min(current_playout_delay_.min_ms, requested_delay.max_ms); |
| } |
| if (requested_delay.max_ms == -1) { |
| requested_delay.max_ms = |
| std::max(current_playout_delay_.max_ms, requested_delay.min_ms); |
| } |
| |
| current_playout_delay_ = requested_delay; |
| playout_delay_pending_ = true; |
| } |
| |
| } // namespace webrtc |
