1 /* 2 * Copyright (c) 2016 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 #ifndef MODULES_RTP_RTCP_INCLUDE_FLEXFEC_SENDER_H_ 12 #define MODULES_RTP_RTCP_INCLUDE_FLEXFEC_SENDER_H_ 13 14 #include <memory> 15 #include <string> 16 #include <vector> 17 18 #include "absl/strings/string_view.h" 19 #include "api/array_view.h" 20 #include "api/rtp_parameters.h" 21 #include "modules/rtp_rtcp/include/rtp_header_extension_map.h" 22 #include "modules/rtp_rtcp/include/rtp_rtcp_defines.h" 23 #include "modules/rtp_rtcp/source/rtp_header_extension_size.h" 24 #include "modules/rtp_rtcp/source/ulpfec_generator.h" 25 #include "modules/rtp_rtcp/source/video_fec_generator.h" 26 #include "rtc_base/random.h" 27 #include "rtc_base/rate_statistics.h" 28 #include "rtc_base/synchronization/mutex.h" 29 30 namespace webrtc { 31 32 class Clock; 33 class RtpPacketToSend; 34 35 // Note that this class is not thread safe, and thus requires external 36 // synchronization. Currently, this is done using the lock in PayloadRouter. 37 38 class FlexfecSender : public VideoFecGenerator { 39 public: 40 FlexfecSender(int payload_type, 41 uint32_t ssrc, 42 uint32_t protected_media_ssrc, 43 absl::string_view mid, 44 const std::vector<RtpExtension>& rtp_header_extensions, 45 rtc::ArrayView<const RtpExtensionSize> extension_sizes, 46 const RtpState* rtp_state, 47 Clock* clock); 48 ~FlexfecSender(); 49 GetFecType()50 FecType GetFecType() const override { 51 return VideoFecGenerator::FecType::kFlexFec; 52 } FecSsrc()53 absl::optional<uint32_t> FecSsrc() override { return ssrc_; } 54 55 // Sets the FEC rate, max frames sent before FEC packets are sent, 56 // and what type of generator matrices are used. 57 void SetProtectionParameters(const FecProtectionParams& delta_params, 58 const FecProtectionParams& key_params) override; 59 60 // Adds a media packet to the internal buffer. When enough media packets 61 // have been added, the FEC packets are generated and stored internally. 62 // These FEC packets are then obtained by calling GetFecPackets(). 63 void AddPacketAndGenerateFec(const RtpPacketToSend& packet) override; 64 65 // Returns generated FlexFEC packets. 66 std::vector<std::unique_ptr<RtpPacketToSend>> GetFecPackets() override; 67 68 // Returns the overhead, per packet, for FlexFEC. 69 size_t MaxPacketOverhead() const override; 70 71 DataRate CurrentFecRate() const override; 72 73 // Only called on the VideoSendStream queue, after operation has shut down. 74 absl::optional<RtpState> GetRtpState() override; 75 76 private: 77 // Utility. 78 Clock* const clock_; 79 Random random_; 80 int64_t last_generated_packet_ms_; 81 82 // Config. 83 const int payload_type_; 84 const uint32_t timestamp_offset_; 85 const uint32_t ssrc_; 86 const uint32_t protected_media_ssrc_; 87 // MID value to send in the MID header extension. 88 const std::string mid_; 89 // Sequence number of next packet to generate. 90 uint16_t seq_num_; 91 92 // Implementation. 93 UlpfecGenerator ulpfec_generator_; 94 const RtpHeaderExtensionMap rtp_header_extension_map_; 95 const size_t header_extensions_size_; 96 97 mutable Mutex mutex_; 98 RateStatistics fec_bitrate_ RTC_GUARDED_BY(mutex_); 99 }; 100 101 } // namespace webrtc 102 103 #endif // MODULES_RTP_RTCP_INCLUDE_FLEXFEC_SENDER_H_ 104