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Diffstat (limited to 'third_party/libwebrtc/modules/rtp_rtcp/source/rtp_fec_unittest.cc')
| -rw-r--r-- | third_party/libwebrtc/modules/rtp_rtcp/source/rtp_fec_unittest.cc | 1129 |
1 files changed, 1129 insertions, 0 deletions
diff --git a/third_party/libwebrtc/modules/rtp_rtcp/source/rtp_fec_unittest.cc b/third_party/libwebrtc/modules/rtp_rtcp/source/rtp_fec_unittest.cc new file mode 100644 index 0000000000..2c01a0d40a --- /dev/null +++ b/third_party/libwebrtc/modules/rtp_rtcp/source/rtp_fec_unittest.cc @@ -0,0 +1,1129 @@ +/* + * 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 <list> +#include <memory> + +#include "absl/algorithm/container.h" +#include "modules/rtp_rtcp/source/byte_io.h" +#include "modules/rtp_rtcp/source/fec_test_helper.h" +#include "modules/rtp_rtcp/source/flexfec_header_reader_writer.h" +#include "modules/rtp_rtcp/source/forward_error_correction.h" +#include "modules/rtp_rtcp/source/ulpfec_header_reader_writer.h" +#include "rtc_base/random.h" +#include "test/gtest.h" + +namespace webrtc { + +namespace { + +// Transport header size in bytes. Assume UDP/IPv4 as a reasonable minimum. +constexpr size_t kTransportOverhead = 28; + +constexpr uint32_t kMediaSsrc = 83542; +constexpr uint32_t kFlexfecSsrc = 43245; + +constexpr size_t kMaxMediaPackets = 48; + +// Deep copies `src` to `dst`, but only keeps every Nth packet. +void DeepCopyEveryNthPacket(const ForwardErrorCorrection::PacketList& src, + int n, + ForwardErrorCorrection::PacketList* dst) { + RTC_DCHECK_GT(n, 0); + int i = 0; + for (const auto& packet : src) { + if (i % n == 0) { + dst->emplace_back(new ForwardErrorCorrection::Packet(*packet)); + } + ++i; + } +} + +} // namespace + +using ::testing::Types; + +template <typename ForwardErrorCorrectionType> +class RtpFecTest : public ::testing::Test { + protected: + RtpFecTest() + : random_(0xabcdef123456), + media_packet_generator_( + kRtpHeaderSize, // Minimum packet size. + IP_PACKET_SIZE - kRtpHeaderSize - kTransportOverhead - + fec_.MaxPacketOverhead(), // Maximum packet size. + kMediaSsrc, + &random_) {} + + // Construct `received_packets_`: a subset of the media and FEC packets. + // + // Media packet "i" is lost if media_loss_mask_[i] = 1, received if + // media_loss_mask_[i] = 0. + // FEC packet "i" is lost if fec_loss_mask_[i] = 1, received if + // fec_loss_mask_[i] = 0. + void NetworkReceivedPackets(int* media_loss_mask, int* fec_loss_mask); + + // Add packet from `packet_list` to list of received packets, using the + // `loss_mask`. + // The `packet_list` may be a media packet list (is_fec = false), or a + // FEC packet list (is_fec = true). + template <typename T> + void ReceivedPackets(const T& packet_list, int* loss_mask, bool is_fec); + + // Check for complete recovery after FEC decoding. + bool IsRecoveryComplete(); + + ForwardErrorCorrectionType fec_; + + Random random_; + test::fec::MediaPacketGenerator media_packet_generator_; + + ForwardErrorCorrection::PacketList media_packets_; + std::list<ForwardErrorCorrection::Packet*> generated_fec_packets_; + std::vector<std::unique_ptr<ForwardErrorCorrection::ReceivedPacket>> + received_packets_; + ForwardErrorCorrection::RecoveredPacketList recovered_packets_; + + int media_loss_mask_[kUlpfecMaxMediaPackets]; + int fec_loss_mask_[kUlpfecMaxMediaPackets]; +}; + +template <typename ForwardErrorCorrectionType> +void RtpFecTest<ForwardErrorCorrectionType>::NetworkReceivedPackets( + int* media_loss_mask, + int* fec_loss_mask) { + constexpr bool kFecPacket = true; + this->received_packets_.clear(); + ReceivedPackets(media_packets_, media_loss_mask, !kFecPacket); + ReceivedPackets(generated_fec_packets_, fec_loss_mask, kFecPacket); +} + +template <typename ForwardErrorCorrectionType> +template <typename PacketListType> +void RtpFecTest<ForwardErrorCorrectionType>::ReceivedPackets( + const PacketListType& packet_list, + int* loss_mask, + bool is_fec) { + uint16_t fec_seq_num = ForwardErrorCorrectionType::GetFirstFecSeqNum( + media_packet_generator_.GetNextSeqNum()); + int packet_idx = 0; + + for (const auto& packet : packet_list) { + if (loss_mask[packet_idx] == 0) { + std::unique_ptr<ForwardErrorCorrection::ReceivedPacket> received_packet( + new ForwardErrorCorrection::ReceivedPacket()); + received_packet->pkt = new ForwardErrorCorrection::Packet(); + received_packet->pkt->data = packet->data; + received_packet->is_fec = is_fec; + if (!is_fec) { + received_packet->ssrc = kMediaSsrc; + // For media packets, the sequence number is obtained from the + // RTP header as written by MediaPacketGenerator::ConstructMediaPackets. + received_packet->seq_num = + ByteReader<uint16_t>::ReadBigEndian(packet->data.data() + 2); + } else { + received_packet->ssrc = ForwardErrorCorrectionType::kFecSsrc; + // For FEC packets, we simulate the sequence numbers differently + // depending on if ULPFEC or FlexFEC is used. See the definition of + // ForwardErrorCorrectionType::GetFirstFecSeqNum. + received_packet->seq_num = fec_seq_num; + } + received_packets_.push_back(std::move(received_packet)); + } + packet_idx++; + // Sequence number of FEC packets are defined as increment by 1 from + // last media packet in frame. + if (is_fec) + fec_seq_num++; + } +} + +template <typename ForwardErrorCorrectionType> +bool RtpFecTest<ForwardErrorCorrectionType>::IsRecoveryComplete() { + // We must have equally many recovered packets as original packets and all + // recovered packets must be identical to the corresponding original packets. + return absl::c_equal( + media_packets_, recovered_packets_, + [](const std::unique_ptr<ForwardErrorCorrection::Packet>& media_packet, + const std::unique_ptr<ForwardErrorCorrection::RecoveredPacket>& + recovered_packet) { + if (media_packet->data.size() != recovered_packet->pkt->data.size()) { + return false; + } + if (memcmp(media_packet->data.cdata(), + recovered_packet->pkt->data.cdata(), + media_packet->data.size()) != 0) { + return false; + } + return true; + }); +} + +// Define gTest typed test to loop over both ULPFEC and FlexFEC. +// Since the tests now are parameterized, we need to access +// member variables using `this`, thereby enforcing runtime +// resolution. + +class FlexfecForwardErrorCorrection : public ForwardErrorCorrection { + public: + static const uint32_t kFecSsrc = kFlexfecSsrc; + + FlexfecForwardErrorCorrection() + : ForwardErrorCorrection( + std::unique_ptr<FecHeaderReader>(new FlexfecHeaderReader()), + std::unique_ptr<FecHeaderWriter>(new FlexfecHeaderWriter()), + kFecSsrc, + kMediaSsrc) {} + + // For FlexFEC we let the FEC packet sequence numbers be independent of + // the media packet sequence numbers. + static uint16_t GetFirstFecSeqNum(uint16_t next_media_seq_num) { + Random random(0xbe110); + return random.Rand<uint16_t>(); + } +}; + +class UlpfecForwardErrorCorrection : public ForwardErrorCorrection { + public: + static const uint32_t kFecSsrc = kMediaSsrc; + + UlpfecForwardErrorCorrection() + : ForwardErrorCorrection( + std::unique_ptr<FecHeaderReader>(new UlpfecHeaderReader()), + std::unique_ptr<FecHeaderWriter>(new UlpfecHeaderWriter()), + kFecSsrc, + kMediaSsrc) {} + + // For ULPFEC we assume that the FEC packets are subsequent to the media + // packets in terms of sequence number. + static uint16_t GetFirstFecSeqNum(uint16_t next_media_seq_num) { + return next_media_seq_num; + } +}; + +using FecTypes = + Types<FlexfecForwardErrorCorrection, UlpfecForwardErrorCorrection>; +TYPED_TEST_SUITE(RtpFecTest, FecTypes); + +TYPED_TEST(RtpFecTest, WillProtectMediaPacketsWithLargeSequenceNumberGap) { + constexpr int kNumImportantPackets = 0; + constexpr bool kUseUnequalProtection = false; + constexpr int kNumMediaPackets = 2; + constexpr uint8_t kProtectionFactor = 127; + + this->media_packets_ = + this->media_packet_generator_.ConstructMediaPackets(kNumMediaPackets); + + // Create |kMaxMediaPackets - 1| sequence number difference. + ByteWriter<uint16_t>::WriteBigEndian( + this->media_packets_.front()->data.MutableData() + 2, 1); + ByteWriter<uint16_t>::WriteBigEndian( + this->media_packets_.back()->data.MutableData() + 2, kMaxMediaPackets); + + EXPECT_EQ( + 0, this->fec_.EncodeFec(this->media_packets_, kProtectionFactor, + kNumImportantPackets, kUseUnequalProtection, + kFecMaskBursty, &this->generated_fec_packets_)); + EXPECT_EQ(1u, this->generated_fec_packets_.size()); +} + +TYPED_TEST(RtpFecTest, + WillNotProtectMediaPacketsWithTooLargeSequenceNumberGap) { + constexpr int kNumImportantPackets = 0; + constexpr bool kUseUnequalProtection = false; + constexpr int kNumMediaPackets = 2; + constexpr uint8_t kProtectionFactor = 127; + + this->media_packets_ = + this->media_packet_generator_.ConstructMediaPackets(kNumMediaPackets); + + // Create `kMaxMediaPackets` sequence number difference. + ByteWriter<uint16_t>::WriteBigEndian( + this->media_packets_.front()->data.MutableData() + 2, 1); + ByteWriter<uint16_t>::WriteBigEndian( + this->media_packets_.back()->data.MutableData() + 2, + kMaxMediaPackets + 1); + + EXPECT_EQ( + -1, this->fec_.EncodeFec(this->media_packets_, kProtectionFactor, + kNumImportantPackets, kUseUnequalProtection, + kFecMaskBursty, &this->generated_fec_packets_)); + EXPECT_TRUE(this->generated_fec_packets_.empty()); +} + +TYPED_TEST(RtpFecTest, FecRecoveryNoLoss) { + constexpr int kNumImportantPackets = 0; + constexpr bool kUseUnequalProtection = false; + constexpr int kNumMediaPackets = 4; + constexpr uint8_t kProtectionFactor = 60; + + this->media_packets_ = + this->media_packet_generator_.ConstructMediaPackets(kNumMediaPackets); + + EXPECT_EQ( + 0, this->fec_.EncodeFec(this->media_packets_, kProtectionFactor, + kNumImportantPackets, kUseUnequalProtection, + kFecMaskBursty, &this->generated_fec_packets_)); + + // Expect 1 FEC packet. + EXPECT_EQ(1u, this->generated_fec_packets_.size()); + + // No packets lost. + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // No packets lost, expect complete recovery. + EXPECT_TRUE(this->IsRecoveryComplete()); +} + +TYPED_TEST(RtpFecTest, FecRecoveryWithLoss) { + constexpr int kNumImportantPackets = 0; + constexpr bool kUseUnequalProtection = false; + constexpr int kNumMediaPackets = 4; + constexpr uint8_t kProtectionFactor = 60; + + this->media_packets_ = + this->media_packet_generator_.ConstructMediaPackets(kNumMediaPackets); + + EXPECT_EQ( + 0, this->fec_.EncodeFec(this->media_packets_, kProtectionFactor, + kNumImportantPackets, kUseUnequalProtection, + kFecMaskBursty, &this->generated_fec_packets_)); + + // Expect 1 FEC packet. + EXPECT_EQ(1u, this->generated_fec_packets_.size()); + + // 1 media packet lost + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[3] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // One packet lost, one FEC packet, expect complete recovery. + EXPECT_TRUE(this->IsRecoveryComplete()); + this->recovered_packets_.clear(); + + // 2 media packets lost. + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[1] = 1; + this->media_loss_mask_[3] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // 2 packets lost, one FEC packet, cannot get complete recovery. + EXPECT_FALSE(this->IsRecoveryComplete()); +} + +// Verify that we don't use an old FEC packet for FEC decoding. +TYPED_TEST(RtpFecTest, NoFecRecoveryWithOldFecPacket) { + constexpr int kNumImportantPackets = 0; + constexpr bool kUseUnequalProtection = false; + constexpr uint8_t kProtectionFactor = 20; + + // Two frames: first frame (old) with two media packets and 1 FEC packet. + // Third frame (new) with 3 media packets, and no FEC packets. + // + // #0(media) #1(media) #2(FEC) ----Frame 1----- + // #32767(media) 32768(media) 32769(media) ----Frame 2----- + // #65535(media) #0(media) #1(media). ----Frame 3----- + // If we lose either packet 0 or 1 of third frame, FEC decoding should not + // try to decode using "old" FEC packet #2. + + // Construct media packets for first frame, starting at sequence number 0. + this->media_packets_ = + this->media_packet_generator_.ConstructMediaPackets(2, 0); + + EXPECT_EQ( + 0, this->fec_.EncodeFec(this->media_packets_, kProtectionFactor, + kNumImportantPackets, kUseUnequalProtection, + kFecMaskBursty, &this->generated_fec_packets_)); + // Expect 1 FEC packet. + EXPECT_EQ(1u, this->generated_fec_packets_.size()); + // Add FEC packet (seq#2) of this first frame to received list (i.e., assume + // the two media packet were lost). + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->ReceivedPackets(this->generated_fec_packets_, this->fec_loss_mask_, + true); + + // Construct media packets for second frame, with sequence number wrap. + this->media_packets_ = + this->media_packet_generator_.ConstructMediaPackets(3, 32767); + + // Expect 3 media packets for this frame. + EXPECT_EQ(3u, this->media_packets_.size()); + + // No packets lost + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + this->ReceivedPackets(this->media_packets_, this->media_loss_mask_, false); + + // Construct media packets for third frame, with sequence number wrap. + this->media_packets_ = + this->media_packet_generator_.ConstructMediaPackets(3, 65535); + + // Expect 3 media packets for this frame. + EXPECT_EQ(3u, this->media_packets_.size()); + + // Second media packet lost (seq#0). + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + this->media_loss_mask_[1] = 1; + // Add packets #65535, and #1 to received list. + this->ReceivedPackets(this->media_packets_, this->media_loss_mask_, false); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // Expect that no decoding is done to get missing packet (seq#0) of third + // frame, using old FEC packet (seq#2) from first (old) frame. So number of + // recovered packets is 5 (0 from first frame, three from second frame, and 2 + // for the third frame, with no packets recovered via FEC). + EXPECT_EQ(5u, this->recovered_packets_.size()); + EXPECT_TRUE(this->recovered_packets_.size() != this->media_packets_.size()); +} + +// Verify we can still recover frame if sequence number wrap occurs within +// the frame and FEC packet following wrap is received after media packets. +TYPED_TEST(RtpFecTest, FecRecoveryWithSeqNumGapOneFrameRecovery) { + constexpr int kNumImportantPackets = 0; + constexpr bool kUseUnequalProtection = false; + constexpr uint8_t kProtectionFactor = 20; + + // One frame, with sequence number wrap in media packets. + // -----Frame 1---- + // #65534(media) #65535(media) #0(media) #1(FEC). + this->media_packets_ = + this->media_packet_generator_.ConstructMediaPackets(3, 65534); + + EXPECT_EQ( + 0, this->fec_.EncodeFec(this->media_packets_, kProtectionFactor, + kNumImportantPackets, kUseUnequalProtection, + kFecMaskBursty, &this->generated_fec_packets_)); + + // Expect 1 FEC packet. + EXPECT_EQ(1u, this->generated_fec_packets_.size()); + + // Lose one media packet (seq# 65535). + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[1] = 1; + this->ReceivedPackets(this->media_packets_, this->media_loss_mask_, false); + // Add FEC packet to received list following the media packets. + this->ReceivedPackets(this->generated_fec_packets_, this->fec_loss_mask_, + true); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // Expect 3 media packets in recovered list, and complete recovery. + // Wrap-around won't remove FEC packet, as it follows the wrap. + EXPECT_EQ(3u, this->recovered_packets_.size()); + EXPECT_TRUE(this->IsRecoveryComplete()); +} + +// Sequence number wrap occurs within the ULPFEC packets for the frame. +// Same problem will occur if wrap is within media packets but ULPFEC packet is +// received before the media packets. This may be improved if timing information +// is used to detect old ULPFEC packets. + +// TODO(nisse): There's some logic to discard ULPFEC packets at wrap-around, +// however, that is not actually exercised by this test: When the first FEC +// packet is processed, it results in full recovery of one media packet and the +// FEC packet is forgotten. And then the wraparound isn't noticed when the next +// FEC packet is received. We should fix wraparound handling, which currently +// appears broken, and then figure out how to test it properly. +using RtpFecTestUlpfecOnly = RtpFecTest<UlpfecForwardErrorCorrection>; +TEST_F(RtpFecTestUlpfecOnly, FecRecoveryWithSeqNumGapOneFrameRecovery) { + constexpr int kNumImportantPackets = 0; + constexpr bool kUseUnequalProtection = false; + constexpr uint8_t kProtectionFactor = 200; + + // 1 frame: 3 media packets and 2 FEC packets. + // Sequence number wrap in FEC packets. + // -----Frame 1---- + // #65532(media) #65533(media) #65534(media) #65535(FEC) #0(FEC). + this->media_packets_ = + this->media_packet_generator_.ConstructMediaPackets(3, 65532); + + EXPECT_EQ( + 0, this->fec_.EncodeFec(this->media_packets_, kProtectionFactor, + kNumImportantPackets, kUseUnequalProtection, + kFecMaskBursty, &this->generated_fec_packets_)); + + // Expect 2 FEC packets. + EXPECT_EQ(2u, this->generated_fec_packets_.size()); + + // Lose the last two media packets (seq# 65533, 65534). + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[1] = 1; + this->media_loss_mask_[2] = 1; + this->ReceivedPackets(this->media_packets_, this->media_loss_mask_, false); + this->ReceivedPackets(this->generated_fec_packets_, this->fec_loss_mask_, + true); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // The two FEC packets are received and should allow for complete recovery, + // but because of the wrap the first FEC packet will be discarded, and only + // one media packet is recoverable. So expect 2 media packets on recovered + // list and no complete recovery. + EXPECT_EQ(3u, this->recovered_packets_.size()); + EXPECT_EQ(this->recovered_packets_.size(), this->media_packets_.size()); + EXPECT_TRUE(this->IsRecoveryComplete()); +} + +// TODO(brandtr): This test mimics the one above, ensuring that the recovery +// strategy of FlexFEC matches the recovery strategy of ULPFEC. Since FlexFEC +// does not share the sequence number space with the media, however, having a +// matching recovery strategy may be suboptimal. Study this further. +// TODO(nisse): In this test, recovery based on the first FEC packet fails with +// the log message "The recovered packet had a length larger than a typical IP +// packet, and is thus dropped." This is probably not intended, and needs +// investigation. +using RtpFecTestFlexfecOnly = RtpFecTest<FlexfecForwardErrorCorrection>; +TEST_F(RtpFecTestFlexfecOnly, FecRecoveryWithSeqNumGapOneFrameNoRecovery) { + constexpr int kNumImportantPackets = 0; + constexpr bool kUseUnequalProtection = false; + constexpr uint8_t kProtectionFactor = 200; + + // 1 frame: 3 media packets and 2 FEC packets. + // Sequence number wrap in FEC packets. + // -----Frame 1---- + // #65532(media) #65533(media) #65534(media) #65535(FEC) #0(FEC). + this->media_packets_ = + this->media_packet_generator_.ConstructMediaPackets(3, 65532); + + EXPECT_EQ( + 0, this->fec_.EncodeFec(this->media_packets_, kProtectionFactor, + kNumImportantPackets, kUseUnequalProtection, + kFecMaskBursty, &this->generated_fec_packets_)); + + // Expect 2 FEC packets. + EXPECT_EQ(2u, this->generated_fec_packets_.size()); + + // Overwrite the sequence numbers generated by ConstructMediaPackets, + // to make sure that we do have a wrap. + auto it = this->generated_fec_packets_.begin(); + ByteWriter<uint16_t>::WriteBigEndian(&(*it)->data.MutableData()[2], 65535); + ++it; + ByteWriter<uint16_t>::WriteBigEndian(&(*it)->data.MutableData()[2], 0); + + // Lose the last two media packets (seq# 65533, 65534). + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[1] = 1; + this->media_loss_mask_[2] = 1; + this->ReceivedPackets(this->media_packets_, this->media_loss_mask_, false); + this->ReceivedPackets(this->generated_fec_packets_, this->fec_loss_mask_, + true); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // The two FEC packets are received and should allow for complete recovery, + // but because of the wrap the first FEC packet will be discarded, and only + // one media packet is recoverable. So expect 2 media packets on recovered + // list and no complete recovery. + EXPECT_EQ(2u, this->recovered_packets_.size()); + EXPECT_TRUE(this->recovered_packets_.size() != this->media_packets_.size()); + EXPECT_FALSE(this->IsRecoveryComplete()); +} + +// Verify we can still recover frame if media packets are reordered. +TYPED_TEST(RtpFecTest, FecRecoveryWithMediaOutOfOrder) { + constexpr int kNumImportantPackets = 0; + constexpr bool kUseUnequalProtection = false; + constexpr uint8_t kProtectionFactor = 20; + + // One frame: 3 media packets, 1 FEC packet. + // -----Frame 1---- + // #0(media) #1(media) #2(media) #3(FEC). + this->media_packets_ = + this->media_packet_generator_.ConstructMediaPackets(3, 0); + + EXPECT_EQ( + 0, this->fec_.EncodeFec(this->media_packets_, kProtectionFactor, + kNumImportantPackets, kUseUnequalProtection, + kFecMaskBursty, &this->generated_fec_packets_)); + + // Expect 1 FEC packet. + EXPECT_EQ(1u, this->generated_fec_packets_.size()); + + // Lose one media packet (seq# 1). + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[1] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + // Reorder received media packets. + auto it0 = this->received_packets_.begin(); + auto it1 = this->received_packets_.begin(); + it1++; + std::swap(*it0, *it1); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // Expect 3 media packets in recovered list, and complete recovery. + EXPECT_EQ(3u, this->recovered_packets_.size()); + EXPECT_TRUE(this->IsRecoveryComplete()); +} + +// Verify we can still recover frame if FEC is received before media packets. +TYPED_TEST(RtpFecTest, FecRecoveryWithFecOutOfOrder) { + constexpr int kNumImportantPackets = 0; + constexpr bool kUseUnequalProtection = false; + constexpr uint8_t kProtectionFactor = 20; + + // One frame: 3 media packets, 1 FEC packet. + // -----Frame 1---- + // #0(media) #1(media) #2(media) #3(FEC). + this->media_packets_ = + this->media_packet_generator_.ConstructMediaPackets(3, 0); + + EXPECT_EQ( + 0, this->fec_.EncodeFec(this->media_packets_, kProtectionFactor, + kNumImportantPackets, kUseUnequalProtection, + kFecMaskBursty, &this->generated_fec_packets_)); + + // Expect 1 FEC packet. + EXPECT_EQ(1u, this->generated_fec_packets_.size()); + + // Lose one media packet (seq# 1). + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[1] = 1; + // Add FEC packet to received list before the media packets. + this->ReceivedPackets(this->generated_fec_packets_, this->fec_loss_mask_, + true); + // Add media packets to received list. + this->ReceivedPackets(this->media_packets_, this->media_loss_mask_, false); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // Expect 3 media packets in recovered list, and complete recovery. + EXPECT_EQ(3u, this->recovered_packets_.size()); + EXPECT_TRUE(this->IsRecoveryComplete()); +} + +// Test 50% protection with random mask type: Two cases are considered: +// a 50% non-consecutive loss which can be fully recovered, and a 50% +// consecutive loss which cannot be fully recovered. +TYPED_TEST(RtpFecTest, FecRecoveryWithLoss50percRandomMask) { + constexpr int kNumImportantPackets = 0; + constexpr bool kUseUnequalProtection = false; + constexpr int kNumMediaPackets = 4; + constexpr uint8_t kProtectionFactor = 255; + + // Packet Mask for (4,4,0) code, from random mask table. + // (kNumMediaPackets = 4; num_fec_packets = 4, kNumImportantPackets = 0) + + // media#0 media#1 media#2 media#3 + // fec#0: 1 1 0 0 + // fec#1: 1 0 1 0 + // fec#2: 0 0 1 1 + // fec#3: 0 1 0 1 + // + + this->media_packets_ = + this->media_packet_generator_.ConstructMediaPackets(kNumMediaPackets); + + EXPECT_EQ( + 0, this->fec_.EncodeFec(this->media_packets_, kProtectionFactor, + kNumImportantPackets, kUseUnequalProtection, + kFecMaskRandom, &this->generated_fec_packets_)); + + // Expect 4 FEC packets. + EXPECT_EQ(4u, this->generated_fec_packets_.size()); + + // 4 packets lost: 3 media packets (0, 2, 3), and one FEC packet (0) lost. + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->fec_loss_mask_[0] = 1; + this->media_loss_mask_[0] = 1; + this->media_loss_mask_[2] = 1; + this->media_loss_mask_[3] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // With media packet#1 and FEC packets #1, #2, #3, expect complete recovery. + EXPECT_TRUE(this->IsRecoveryComplete()); + this->recovered_packets_.clear(); + + // 4 consecutive packets lost: media packets 0, 1, 2, 3. + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[0] = 1; + this->media_loss_mask_[1] = 1; + this->media_loss_mask_[2] = 1; + this->media_loss_mask_[3] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // Cannot get complete recovery for this loss configuration with random mask. + EXPECT_FALSE(this->IsRecoveryComplete()); +} + +// Test 50% protection with bursty type: Three cases are considered: +// two 50% consecutive losses which can be fully recovered, and one +// non-consecutive which cannot be fully recovered. +TYPED_TEST(RtpFecTest, FecRecoveryWithLoss50percBurstyMask) { + constexpr int kNumImportantPackets = 0; + constexpr bool kUseUnequalProtection = false; + constexpr int kNumMediaPackets = 4; + constexpr uint8_t kProtectionFactor = 255; + + // Packet Mask for (4,4,0) code, from bursty mask table. + // (kNumMediaPackets = 4; num_fec_packets = 4, kNumImportantPackets = 0) + + // media#0 media#1 media#2 media#3 + // fec#0: 1 0 0 0 + // fec#1: 1 1 0 0 + // fec#2: 0 1 1 0 + // fec#3: 0 0 1 1 + // + + this->media_packets_ = + this->media_packet_generator_.ConstructMediaPackets(kNumMediaPackets); + + EXPECT_EQ( + 0, this->fec_.EncodeFec(this->media_packets_, kProtectionFactor, + kNumImportantPackets, kUseUnequalProtection, + kFecMaskBursty, &this->generated_fec_packets_)); + + // Expect 4 FEC packets. + EXPECT_EQ(4u, this->generated_fec_packets_.size()); + + // 4 consecutive packets lost: media packets 0,1,2,3. + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[0] = 1; + this->media_loss_mask_[1] = 1; + this->media_loss_mask_[2] = 1; + this->media_loss_mask_[3] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // Expect complete recovery for consecutive packet loss <= 50%. + EXPECT_TRUE(this->IsRecoveryComplete()); + this->recovered_packets_.clear(); + + // 4 consecutive packets lost: media packets 1,2, 3, and FEC packet 0. + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->fec_loss_mask_[0] = 1; + this->media_loss_mask_[1] = 1; + this->media_loss_mask_[2] = 1; + this->media_loss_mask_[3] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // Expect complete recovery for consecutive packet loss <= 50%. + EXPECT_TRUE(this->IsRecoveryComplete()); + this->recovered_packets_.clear(); + + // 4 packets lost (non-consecutive loss): media packets 0, 3, and FEC# 0, 3. + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->fec_loss_mask_[0] = 1; + this->fec_loss_mask_[3] = 1; + this->media_loss_mask_[0] = 1; + this->media_loss_mask_[3] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // Cannot get complete recovery for this loss configuration. + EXPECT_FALSE(this->IsRecoveryComplete()); +} + +TYPED_TEST(RtpFecTest, FecRecoveryNoLossUep) { + constexpr int kNumImportantPackets = 2; + constexpr bool kUseUnequalProtection = true; + constexpr int kNumMediaPackets = 4; + constexpr uint8_t kProtectionFactor = 60; + + this->media_packets_ = + this->media_packet_generator_.ConstructMediaPackets(kNumMediaPackets); + + EXPECT_EQ( + 0, this->fec_.EncodeFec(this->media_packets_, kProtectionFactor, + kNumImportantPackets, kUseUnequalProtection, + kFecMaskBursty, &this->generated_fec_packets_)); + + // Expect 1 FEC packet. + EXPECT_EQ(1u, this->generated_fec_packets_.size()); + + // No packets lost. + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // No packets lost, expect complete recovery. + EXPECT_TRUE(this->IsRecoveryComplete()); +} + +TYPED_TEST(RtpFecTest, FecRecoveryWithLossUep) { + constexpr int kNumImportantPackets = 2; + constexpr bool kUseUnequalProtection = true; + constexpr int kNumMediaPackets = 4; + constexpr uint8_t kProtectionFactor = 60; + + this->media_packets_ = + this->media_packet_generator_.ConstructMediaPackets(kNumMediaPackets); + + EXPECT_EQ( + 0, this->fec_.EncodeFec(this->media_packets_, kProtectionFactor, + kNumImportantPackets, kUseUnequalProtection, + kFecMaskBursty, &this->generated_fec_packets_)); + + // Expect 1 FEC packet. + EXPECT_EQ(1u, this->generated_fec_packets_.size()); + + // 1 media packet lost. + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[3] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // One packet lost, one FEC packet, expect complete recovery. + EXPECT_TRUE(this->IsRecoveryComplete()); + this->recovered_packets_.clear(); + + // 2 media packets lost. + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[1] = 1; + this->media_loss_mask_[3] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // 2 packets lost, one FEC packet, cannot get complete recovery. + EXPECT_FALSE(this->IsRecoveryComplete()); +} + +// Test 50% protection with random mask type for UEP on. +TYPED_TEST(RtpFecTest, FecRecoveryWithLoss50percUepRandomMask) { + constexpr int kNumImportantPackets = 1; + constexpr bool kUseUnequalProtection = true; + constexpr int kNumMediaPackets = 4; + constexpr uint8_t kProtectionFactor = 255; + + // Packet Mask for (4,4,1) code, from random mask table. + // (kNumMediaPackets = 4; num_fec_packets = 4, kNumImportantPackets = 1) + + // media#0 media#1 media#2 media#3 + // fec#0: 1 0 0 0 + // fec#1: 1 1 0 0 + // fec#2: 1 0 1 1 + // fec#3: 0 1 1 0 + // + + this->media_packets_ = + this->media_packet_generator_.ConstructMediaPackets(kNumMediaPackets); + + EXPECT_EQ( + 0, this->fec_.EncodeFec(this->media_packets_, kProtectionFactor, + kNumImportantPackets, kUseUnequalProtection, + kFecMaskRandom, &this->generated_fec_packets_)); + + // Expect 4 FEC packets. + EXPECT_EQ(4u, this->generated_fec_packets_.size()); + + // 4 packets lost: 3 media packets and FEC packet#1 lost. + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->fec_loss_mask_[1] = 1; + this->media_loss_mask_[0] = 1; + this->media_loss_mask_[2] = 1; + this->media_loss_mask_[3] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // With media packet#3 and FEC packets #0, #1, #3, expect complete recovery. + EXPECT_TRUE(this->IsRecoveryComplete()); + this->recovered_packets_.clear(); + + // 5 packets lost: 4 media packets and one FEC packet#2 lost. + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->fec_loss_mask_[2] = 1; + this->media_loss_mask_[0] = 1; + this->media_loss_mask_[1] = 1; + this->media_loss_mask_[2] = 1; + this->media_loss_mask_[3] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // Cannot get complete recovery for this loss configuration. + EXPECT_FALSE(this->IsRecoveryComplete()); +} + +TYPED_TEST(RtpFecTest, FecRecoveryNonConsecutivePackets) { + constexpr int kNumImportantPackets = 0; + constexpr bool kUseUnequalProtection = false; + constexpr int kNumMediaPackets = 5; + constexpr uint8_t kProtectionFactor = 60; + + this->media_packets_ = + this->media_packet_generator_.ConstructMediaPackets(kNumMediaPackets); + + // Create a new temporary packet list for generating FEC packets. + // This list should have every other packet removed. + ForwardErrorCorrection::PacketList protected_media_packets; + DeepCopyEveryNthPacket(this->media_packets_, 2, &protected_media_packets); + + EXPECT_EQ( + 0, this->fec_.EncodeFec(protected_media_packets, kProtectionFactor, + kNumImportantPackets, kUseUnequalProtection, + kFecMaskBursty, &this->generated_fec_packets_)); + + // Expect 1 FEC packet. + EXPECT_EQ(1u, this->generated_fec_packets_.size()); + + // 1 protected media packet lost + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[2] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // One packet lost, one FEC packet, expect complete recovery. + EXPECT_TRUE(this->IsRecoveryComplete()); + this->recovered_packets_.clear(); + + // Unprotected packet lost. + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[1] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // Unprotected packet lost. Recovery not possible. + EXPECT_FALSE(this->IsRecoveryComplete()); + this->recovered_packets_.clear(); + + // 2 media packets lost. + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[0] = 1; + this->media_loss_mask_[2] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // 2 protected packets lost, one FEC packet, cannot get complete recovery. + EXPECT_FALSE(this->IsRecoveryComplete()); +} + +TYPED_TEST(RtpFecTest, FecRecoveryNonConsecutivePacketsExtension) { + constexpr int kNumImportantPackets = 0; + constexpr bool kUseUnequalProtection = false; + constexpr int kNumMediaPackets = 21; + uint8_t kProtectionFactor = 127; + + this->media_packets_ = + this->media_packet_generator_.ConstructMediaPackets(kNumMediaPackets); + + // Create a new temporary packet list for generating FEC packets. + // This list should have every other packet removed. + ForwardErrorCorrection::PacketList protected_media_packets; + DeepCopyEveryNthPacket(this->media_packets_, 2, &protected_media_packets); + + // Zero column insertion will have to extend the size of the packet + // mask since the number of actual packets are 21, while the number + // of protected packets are 11. + EXPECT_EQ( + 0, this->fec_.EncodeFec(protected_media_packets, kProtectionFactor, + kNumImportantPackets, kUseUnequalProtection, + kFecMaskBursty, &this->generated_fec_packets_)); + + // Expect 5 FEC packet. + EXPECT_EQ(5u, this->generated_fec_packets_.size()); + + // Last protected media packet lost + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[kNumMediaPackets - 1] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // One packet lost, one FEC packet, expect complete recovery. + EXPECT_TRUE(this->IsRecoveryComplete()); + this->recovered_packets_.clear(); + + // Last unprotected packet lost. + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[kNumMediaPackets - 2] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // Unprotected packet lost. Recovery not possible. + EXPECT_FALSE(this->IsRecoveryComplete()); + this->recovered_packets_.clear(); + + // 6 media packets lost. + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[kNumMediaPackets - 11] = 1; + this->media_loss_mask_[kNumMediaPackets - 9] = 1; + this->media_loss_mask_[kNumMediaPackets - 7] = 1; + this->media_loss_mask_[kNumMediaPackets - 5] = 1; + this->media_loss_mask_[kNumMediaPackets - 3] = 1; + this->media_loss_mask_[kNumMediaPackets - 1] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // 5 protected packets lost, one FEC packet, cannot get complete recovery. + EXPECT_FALSE(this->IsRecoveryComplete()); +} + +TYPED_TEST(RtpFecTest, FecRecoveryNonConsecutivePacketsWrap) { + constexpr int kNumImportantPackets = 0; + constexpr bool kUseUnequalProtection = false; + constexpr int kNumMediaPackets = 21; + uint8_t kProtectionFactor = 127; + + this->media_packets_ = this->media_packet_generator_.ConstructMediaPackets( + kNumMediaPackets, 0xFFFF - 5); + + // Create a new temporary packet list for generating FEC packets. + // This list should have every other packet removed. + ForwardErrorCorrection::PacketList protected_media_packets; + DeepCopyEveryNthPacket(this->media_packets_, 2, &protected_media_packets); + + // Zero column insertion will have to extend the size of the packet + // mask since the number of actual packets are 21, while the number + // of protected packets are 11. + EXPECT_EQ( + 0, this->fec_.EncodeFec(protected_media_packets, kProtectionFactor, + kNumImportantPackets, kUseUnequalProtection, + kFecMaskBursty, &this->generated_fec_packets_)); + + // Expect 5 FEC packet. + EXPECT_EQ(5u, this->generated_fec_packets_.size()); + + // Last protected media packet lost + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[kNumMediaPackets - 1] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // One packet lost, one FEC packet, expect complete recovery. + EXPECT_TRUE(this->IsRecoveryComplete()); + this->recovered_packets_.clear(); + + // Last unprotected packet lost. + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[kNumMediaPackets - 2] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // Unprotected packet lost. Recovery not possible. + EXPECT_FALSE(this->IsRecoveryComplete()); + this->recovered_packets_.clear(); + + // 6 media packets lost. + memset(this->media_loss_mask_, 0, sizeof(this->media_loss_mask_)); + memset(this->fec_loss_mask_, 0, sizeof(this->fec_loss_mask_)); + this->media_loss_mask_[kNumMediaPackets - 11] = 1; + this->media_loss_mask_[kNumMediaPackets - 9] = 1; + this->media_loss_mask_[kNumMediaPackets - 7] = 1; + this->media_loss_mask_[kNumMediaPackets - 5] = 1; + this->media_loss_mask_[kNumMediaPackets - 3] = 1; + this->media_loss_mask_[kNumMediaPackets - 1] = 1; + this->NetworkReceivedPackets(this->media_loss_mask_, this->fec_loss_mask_); + + for (const auto& received_packet : this->received_packets_) { + this->fec_.DecodeFec(*received_packet, &this->recovered_packets_); + } + + // 5 protected packets lost, one FEC packet, cannot get complete recovery. + EXPECT_FALSE(this->IsRecoveryComplete()); +} + +} // namespace webrtc |