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 #ifndef MODULES_RTP_RTCP_SOURCE_FEC_TEST_HELPER_H_ 12 #define MODULES_RTP_RTCP_SOURCE_FEC_TEST_HELPER_H_ 13 14 #include <memory> 15 16 #include "modules/rtp_rtcp/source/forward_error_correction.h" 17 #include "modules/rtp_rtcp/source/rtp_packet_received.h" 18 #include "rtc_base/random.h" 19 20 namespace webrtc { 21 namespace test { 22 namespace fec { 23 24 struct AugmentedPacket : public ForwardErrorCorrection::Packet { 25 RTPHeader header; 26 }; 27 28 // TODO(brandtr): Consider merging MediaPacketGenerator and 29 // AugmentedPacketGenerator into a single class, since their functionality is 30 // similar. 31 32 // This class generates media packets corresponding to a single frame. 33 class MediaPacketGenerator { 34 public: 35 MediaPacketGenerator(uint32_t min_packet_size, 36 uint32_t max_packet_size, 37 uint32_t ssrc, 38 Random* random); 39 ~MediaPacketGenerator(); 40 41 // Construct the media packets, up to `num_media_packets` packets. 42 ForwardErrorCorrection::PacketList ConstructMediaPackets( 43 int num_media_packets, 44 uint16_t start_seq_num); 45 ForwardErrorCorrection::PacketList ConstructMediaPackets( 46 int num_media_packets); 47 48 uint16_t GetNextSeqNum(); 49 50 private: 51 uint32_t min_packet_size_; 52 uint32_t max_packet_size_; 53 uint32_t ssrc_; 54 Random* random_; 55 56 ForwardErrorCorrection::PacketList media_packets_; 57 uint16_t next_seq_num_; 58 }; 59 60 // This class generates media packets with a certain structure of the payload. 61 class AugmentedPacketGenerator { 62 public: 63 explicit AugmentedPacketGenerator(uint32_t ssrc); 64 65 // Prepare for generating a new set of packets, corresponding to a frame. 66 void NewFrame(size_t num_packets); 67 68 // Increment and return the newly incremented sequence number. 69 uint16_t NextPacketSeqNum(); 70 71 // Return the next packet in the current frame. 72 std::unique_ptr<AugmentedPacket> NextPacket(size_t offset, size_t length); 73 74 protected: 75 // Given `header`, writes the appropriate RTP header fields in `data`. 76 static void WriteRtpHeader(const RTPHeader& header, uint8_t* data); 77 78 // Number of packets left to generate, in the current frame. 79 size_t num_packets_; 80 81 private: 82 uint32_t ssrc_; 83 uint16_t seq_num_; 84 uint32_t timestamp_; 85 }; 86 87 // This class generates media and FlexFEC packets for a single frame. 88 class FlexfecPacketGenerator : public AugmentedPacketGenerator { 89 public: 90 FlexfecPacketGenerator(uint32_t media_ssrc, uint32_t flexfec_ssrc); 91 92 // Creates a new AugmentedPacket (with RTP headers) from a 93 // FlexFEC packet (without RTP headers). 94 std::unique_ptr<AugmentedPacket> BuildFlexfecPacket( 95 const ForwardErrorCorrection::Packet& packet); 96 97 private: 98 uint32_t flexfec_ssrc_; 99 uint16_t flexfec_seq_num_; 100 uint32_t flexfec_timestamp_; 101 }; 102 103 // This class generates media and ULPFEC packets (both encapsulated in RED) 104 // for a single frame. 105 class UlpfecPacketGenerator : public AugmentedPacketGenerator { 106 public: 107 explicit UlpfecPacketGenerator(uint32_t ssrc); 108 109 // Creates a new RtpPacket with the RED header added to the packet. 110 static RtpPacketReceived BuildMediaRedPacket(const AugmentedPacket& packet, 111 bool is_recovered); 112 113 // Creates a new RtpPacket with FEC payload and RED header. Does this by 114 // creating a new fake media AugmentedPacket, clears the marker bit and adds a 115 // RED header. Finally replaces the payload with the content of 116 // `packet->data`. 117 RtpPacketReceived BuildUlpfecRedPacket( 118 const ForwardErrorCorrection::Packet& packet); 119 }; 120 121 } // namespace fec 122 } // namespace test 123 } // namespace webrtc 124 125 #endif // MODULES_RTP_RTCP_SOURCE_FEC_TEST_HELPER_H_ 126