1 files changed, 525 insertions, 0 deletions
diff --git a/third_party/libwebrtc/modules/rtp_rtcp/source/rtp_packetizer_h265_unittest.cc b/third_party/libwebrtc/modules/rtp_rtcp/source/rtp_packetizer_h265_unittest.cc
new file mode 100644
index 0000000000..cb1de334c0
--- /dev/null
+++ b/third_party/libwebrtc/modules/rtp_rtcp/source/rtp_packetizer_h265_unittest.cc
@@ -0,0 +1,525 @@
+/*
+ *  Copyright (c) 2023 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_packetizer_h265.h"
+
+#include <vector>
+
+#include "common_video/h265/h265_common.h"
+#include "modules/rtp_rtcp/mocks/mock_rtp_rtcp.h"
+#include "modules/rtp_rtcp/source/byte_io.h"
+#include "test/gmock.h"
+#include "test/gtest.h"
+
+namespace webrtc {
+namespace {
+
+using ::testing::Each;
+using ::testing::ElementsAre;
+using ::testing::ElementsAreArray;
+using ::testing::Eq;
+using ::testing::IsEmpty;
+using ::testing::SizeIs;
+
+constexpr RtpPacketToSend::ExtensionManager* kNoExtensions = nullptr;
+constexpr size_t kMaxPayloadSize = 1200;
+constexpr size_t kLengthFieldLength = 2;
+constexpr RtpPacketizer::PayloadSizeLimits kNoLimits;
+
+constexpr size_t kNalHeaderSize = 2;
+constexpr size_t kFuHeaderSize = 3;
+
+constexpr uint8_t kNaluTypeMask = 0x7E;
+
+// Bit masks for FU headers.
+constexpr uint8_t kH265SBit = 0x80;
+constexpr uint8_t kH265EBit = 0x40;
+
+// Creates Buffer that looks like nal unit of given size.
+rtc::Buffer GenerateNalUnit(size_t size) {
+  RTC_CHECK_GT(size, 0);
+  rtc::Buffer buffer(size);
+  // Set some valid header with type TRAIL_R and temporal id
+  buffer[0] = 2;
+  buffer[1] = 2;
+  for (size_t i = 2; i < size; ++i) {
+    buffer[i] = static_cast<uint8_t>(i);
+  }
+  // Last byte shouldn't be 0, or it may be counted as part of next 4-byte start
+  // sequence.
+  buffer[size - 1] |= 0x10;
+  return buffer;
+}
+
+// Create frame consisting of nalus of given size.
+rtc::Buffer CreateFrame(std::initializer_list<size_t> nalu_sizes) {
+  static constexpr int kStartCodeSize = 3;
+  rtc::Buffer frame(absl::c_accumulate(nalu_sizes, size_t{0}) +
+                    kStartCodeSize * nalu_sizes.size());
+  size_t offset = 0;
+  for (size_t nalu_size : nalu_sizes) {
+    EXPECT_GE(nalu_size, 1u);
+    // Insert nalu start code
+    frame[offset] = 0;
+    frame[offset + 1] = 0;
+    frame[offset + 2] = 1;
+    // Set some valid header.
+    frame[offset + 3] = 2;
+    // Fill payload avoiding accidental start codes
+    if (nalu_size > 1) {
+      memset(frame.data() + offset + 4, 0x3f, nalu_size - 1);
+    }
+    offset += (kStartCodeSize + nalu_size);
+  }
+  return frame;
+}
+
+// Create frame consisting of given nalus.
+rtc::Buffer CreateFrame(rtc::ArrayView<const rtc::Buffer> nalus) {
+  static constexpr int kStartCodeSize = 3;
+  int frame_size = 0;
+  for (const rtc::Buffer& nalu : nalus) {
+    frame_size += (kStartCodeSize + nalu.size());
+  }
+  rtc::Buffer frame(frame_size);
+  size_t offset = 0;
+  for (const rtc::Buffer& nalu : nalus) {
+    // Insert nalu start code
+    frame[offset] = 0;
+    frame[offset + 1] = 0;
+    frame[offset + 2] = 1;
+    // Copy the nalu unit.
+    memcpy(frame.data() + offset + 3, nalu.data(), nalu.size());
+    offset += (kStartCodeSize + nalu.size());
+  }
+  return frame;
+}
+
+std::vector<RtpPacketToSend> FetchAllPackets(RtpPacketizerH265* packetizer) {
+  std::vector<RtpPacketToSend> result;
+  size_t num_packets = packetizer->NumPackets();
+  result.reserve(num_packets);
+  RtpPacketToSend packet(kNoExtensions);
+  while (packetizer->NextPacket(&packet)) {
+    result.push_back(packet);
+  }
+  EXPECT_THAT(result, SizeIs(num_packets));
+  return result;
+}
+
+// Single nalu tests.
+TEST(RtpPacketizerH265Test, SingleNalu) {
+  const uint8_t frame[] = {0, 0, 1, H265::kIdrWRadl, 0xFF};
+
+  RtpPacketizerH265 packetizer(frame, kNoLimits);
+  std::vector<RtpPacketToSend> packets = FetchAllPackets(&packetizer);
+
+  ASSERT_THAT(packets, SizeIs(1));
+  EXPECT_THAT(packets[0].payload(), ElementsAre(H265::kIdrWRadl, 0xFF));
+}
+
+TEST(RtpPacketizerH265Test, SingleNaluTwoPackets) {
+  RtpPacketizer::PayloadSizeLimits limits;
+  limits.max_payload_len = kMaxPayloadSize;
+  rtc::Buffer nalus[] = {GenerateNalUnit(kMaxPayloadSize),
+                         GenerateNalUnit(100)};
+  rtc::Buffer frame = CreateFrame(nalus);
+
+  RtpPacketizerH265 packetizer(frame, limits);
+  std::vector<RtpPacketToSend> packets = FetchAllPackets(&packetizer);
+
+  ASSERT_THAT(packets, SizeIs(2));
+  EXPECT_THAT(packets[0].payload(), ElementsAreArray(nalus[0]));
+  EXPECT_THAT(packets[1].payload(), ElementsAreArray(nalus[1]));
+}
+
+TEST(RtpPacketizerH265Test,
+     SingleNaluFirstPacketReductionAppliesOnlyToFirstFragment) {
+  RtpPacketizer::PayloadSizeLimits limits;
+  limits.max_payload_len = 200;
+  limits.first_packet_reduction_len = 5;
+  rtc::Buffer nalus[] = {GenerateNalUnit(/*size=*/195),
+                         GenerateNalUnit(/*size=*/200),
+                         GenerateNalUnit(/*size=*/200)};
+  rtc::Buffer frame = CreateFrame(nalus);
+
+  RtpPacketizerH265 packetizer(frame, limits);
+  std::vector<RtpPacketToSend> packets = FetchAllPackets(&packetizer);
+
+  ASSERT_THAT(packets, SizeIs(3));
+  EXPECT_THAT(packets[0].payload(), ElementsAreArray(nalus[0]));
+  EXPECT_THAT(packets[1].payload(), ElementsAreArray(nalus[1]));
+  EXPECT_THAT(packets[2].payload(), ElementsAreArray(nalus[2]));
+}
+
+TEST(RtpPacketizerH265Test,
+     SingleNaluLastPacketReductionAppliesOnlyToLastFragment) {
+  RtpPacketizer::PayloadSizeLimits limits;
+  limits.max_payload_len = 200;
+  limits.last_packet_reduction_len = 5;
+  rtc::Buffer nalus[] = {GenerateNalUnit(/*size=*/200),
+                         GenerateNalUnit(/*size=*/200),
+                         GenerateNalUnit(/*size=*/195)};
+  rtc::Buffer frame = CreateFrame(nalus);
+
+  RtpPacketizerH265 packetizer(frame, limits);
+  std::vector<RtpPacketToSend> packets = FetchAllPackets(&packetizer);
+
+  ASSERT_THAT(packets, SizeIs(3));
+  EXPECT_THAT(packets[0].payload(), ElementsAreArray(nalus[0]));
+  EXPECT_THAT(packets[1].payload(), ElementsAreArray(nalus[1]));
+  EXPECT_THAT(packets[2].payload(), ElementsAreArray(nalus[2]));
+}
+
+TEST(RtpPacketizerH265Test,
+     SingleNaluFirstAndLastPacketReductionSumsForSinglePacket) {
+  RtpPacketizer::PayloadSizeLimits limits;
+  limits.max_payload_len = 200;
+  limits.first_packet_reduction_len = 20;
+  limits.last_packet_reduction_len = 30;
+  rtc::Buffer frame = CreateFrame({150});
+
+  RtpPacketizerH265 packetizer(frame, limits);
+  std::vector<RtpPacketToSend> packets = FetchAllPackets(&packetizer);
+
+  EXPECT_THAT(packets, SizeIs(1));
+}
+
+// Aggregation tests.
+TEST(RtpPacketizerH265Test, ApRespectsNoPacketReduction) {
+  rtc::Buffer nalus[] = {GenerateNalUnit(/*size=*/2),
+                         GenerateNalUnit(/*size=*/2),
+                         GenerateNalUnit(/*size=*/0x123)};
+  rtc::Buffer frame = CreateFrame(nalus);
+
+  RtpPacketizerH265 packetizer(frame, kNoLimits);
+  std::vector<RtpPacketToSend> packets = FetchAllPackets(&packetizer);
+
+  ASSERT_THAT(packets, SizeIs(1));
+  auto payload = packets[0].payload();
+  int type = H265::ParseNaluType(payload[0]);
+  EXPECT_EQ(payload.size(),
+            kNalHeaderSize + 3 * kLengthFieldLength + 2 + 2 + 0x123);
+
+  EXPECT_EQ(type, H265::NaluType::kAp);
+  payload = payload.subview(kNalHeaderSize);
+  // 1st fragment.
+  EXPECT_THAT(payload.subview(0, kLengthFieldLength),
+              ElementsAre(0, 2));  // Size.
+  EXPECT_THAT(payload.subview(kLengthFieldLength, 2),
+              ElementsAreArray(nalus[0]));
+  payload = payload.subview(kLengthFieldLength + 2);
+  // 2nd fragment.
+  EXPECT_THAT(payload.subview(0, kLengthFieldLength),
+              ElementsAre(0, 2));  // Size.
+  EXPECT_THAT(payload.subview(kLengthFieldLength, 2),
+              ElementsAreArray(nalus[1]));
+  payload = payload.subview(kLengthFieldLength + 2);
+  // 3rd fragment.
+  EXPECT_THAT(payload.subview(0, kLengthFieldLength),
+              ElementsAre(0x1, 0x23));  // Size.
+  EXPECT_THAT(payload.subview(kLengthFieldLength), ElementsAreArray(nalus[2]));
+}
+
+TEST(RtpPacketizerH265Test, ApRespectsFirstPacketReduction) {
+  RtpPacketizer::PayloadSizeLimits limits;
+  limits.max_payload_len = 1000;
+  limits.first_packet_reduction_len = 100;
+  const size_t kFirstFragmentSize =
+      limits.max_payload_len - limits.first_packet_reduction_len;
+  rtc::Buffer nalus[] = {GenerateNalUnit(/*size=*/kFirstFragmentSize),
+                         GenerateNalUnit(/*size=*/2),
+                         GenerateNalUnit(/*size=*/2)};
+  rtc::Buffer frame = CreateFrame(nalus);
+
+  RtpPacketizerH265 packetizer(frame, limits);
+  std::vector<RtpPacketToSend> packets = FetchAllPackets(&packetizer);
+
+  ASSERT_THAT(packets, SizeIs(2));
+  // Expect 1st packet is single nalu.
+  EXPECT_THAT(packets[0].payload(), ElementsAreArray(nalus[0]));
+  // Expect 2nd packet is aggregate of last two fragments.
+  // The size of H265 nal_unit_header is 2 bytes, according to 7.3.1.2
+  // in H265 spec. Aggregation packet type is 48, and nuh_temporal_id_plus1
+  // is 2, so the nal_unit_header should be "01100000 00000010",
+  // which is 96 and 2.
+  EXPECT_THAT(packets[1].payload(),
+              ElementsAre(96, 2,                           //
+                          0, 2, nalus[1][0], nalus[1][1],  //
+                          0, 2, nalus[2][0], nalus[2][1]));
+}
+
+TEST(RtpPacketizerH265Test, ApRespectsLastPacketReduction) {
+  RtpPacketizer::PayloadSizeLimits limits;
+  limits.max_payload_len = 1000;
+  limits.last_packet_reduction_len = 100;
+  const size_t kLastFragmentSize =
+      limits.max_payload_len - limits.last_packet_reduction_len;
+  rtc::Buffer nalus[] = {GenerateNalUnit(/*size=*/2),
+                         GenerateNalUnit(/*size=*/2),
+                         GenerateNalUnit(/*size=*/kLastFragmentSize)};
+  rtc::Buffer frame = CreateFrame(nalus);
+
+  RtpPacketizerH265 packetizer(frame, limits);
+  std::vector<RtpPacketToSend> packets = FetchAllPackets(&packetizer);
+
+  ASSERT_THAT(packets, SizeIs(2));
+  // Expect 1st packet is aggregate of 1st two fragments.
+  EXPECT_THAT(packets[0].payload(),
+              ElementsAre(96, 2,                           //
+                          0, 2, nalus[0][0], nalus[0][1],  //
+                          0, 2, nalus[1][0], nalus[1][1]));
+  // Expect 2nd packet is single nalu.
+  EXPECT_THAT(packets[1].payload(), ElementsAreArray(nalus[2]));
+}
+
+TEST(RtpPacketizerH265Test, TooSmallForApHeaders) {
+  RtpPacketizer::PayloadSizeLimits limits;
+  limits.max_payload_len = 1000;
+  const size_t kLastFragmentSize =
+      limits.max_payload_len - 3 * kLengthFieldLength - 4;
+  rtc::Buffer nalus[] = {GenerateNalUnit(/*size=*/2),
+                         GenerateNalUnit(/*size=*/2),
+                         GenerateNalUnit(/*size=*/kLastFragmentSize)};
+  rtc::Buffer frame = CreateFrame(nalus);
+
+  RtpPacketizerH265 packetizer(frame, limits);
+  std::vector<RtpPacketToSend> packets = FetchAllPackets(&packetizer);
+
+  ASSERT_THAT(packets, SizeIs(2));
+  // Expect 1st packet is aggregate of 1st two fragments.
+  EXPECT_THAT(packets[0].payload(),
+              ElementsAre(96, 2,                           //
+                          0, 2, nalus[0][0], nalus[0][1],  //
+                          0, 2, nalus[1][0], nalus[1][1]));
+  // Expect 2nd packet is single nalu.
+  EXPECT_THAT(packets[1].payload(), ElementsAreArray(nalus[2]));
+}
+
+TEST(RtpPacketizerH265Test, LastFragmentFitsInSingleButNotLastPacket) {
+  RtpPacketizer::PayloadSizeLimits limits;
+  limits.max_payload_len = 1178;
+  limits.first_packet_reduction_len = 0;
+  limits.last_packet_reduction_len = 20;
+  limits.single_packet_reduction_len = 20;
+  // Actual sizes, which triggered this bug.
+  rtc::Buffer frame = CreateFrame({20, 8, 18, 1161});
+
+  RtpPacketizerH265 packetizer(frame, limits);
+  std::vector<RtpPacketToSend> packets = FetchAllPackets(&packetizer);
+
+  // Last packet has to be of correct size.
+  // Incorrect implementation might miss this constraint and not split the last
+  // fragment in two packets.
+  EXPECT_LE(static_cast<int>(packets.back().payload_size()),
+            limits.max_payload_len - limits.last_packet_reduction_len);
+}
+
+// Splits frame with payload size `frame_payload_size` without fragmentation,
+// Returns sizes of the payloads excluding FU headers.
+std::vector<int> TestFu(size_t frame_payload_size,
+                        const RtpPacketizer::PayloadSizeLimits& limits) {
+  rtc::Buffer nalu[] = {GenerateNalUnit(kNalHeaderSize + frame_payload_size)};
+  rtc::Buffer frame = CreateFrame(nalu);
+
+  RtpPacketizerH265 packetizer(frame, limits);
+  std::vector<RtpPacketToSend> packets = FetchAllPackets(&packetizer);
+
+  EXPECT_GE(packets.size(), 2u);  // Single packet indicates it is not FU.
+  std::vector<uint16_t> fu_header;
+  std::vector<int> payload_sizes;
+
+  for (const RtpPacketToSend& packet : packets) {
+    auto payload = packet.payload();
+    EXPECT_GT(payload.size(), kFuHeaderSize);
+    // FU header is after the 2-bytes size PayloadHdr according to 4.4.3 in spec
+    fu_header.push_back(payload[2]);
+    payload_sizes.push_back(payload.size() - kFuHeaderSize);
+  }
+
+  EXPECT_TRUE(fu_header.front() & kH265SBit);
+  EXPECT_TRUE(fu_header.back() & kH265EBit);
+  // Clear S and E bits before testing all are duplicating same original header.
+  fu_header.front() &= ~kH265SBit;
+  fu_header.back() &= ~kH265EBit;
+  uint8_t nalu_type = (nalu[0][0] & kNaluTypeMask) >> 1;
+  EXPECT_THAT(fu_header, Each(Eq(nalu_type)));
+
+  return payload_sizes;
+}
+
+// Fragmentation tests.
+TEST(RtpPacketizerH265Test, FuOddSize) {
+  RtpPacketizer::PayloadSizeLimits limits;
+  limits.max_payload_len = 1200;
+  EXPECT_THAT(TestFu(1200, limits), ElementsAre(600, 600));
+}
+
+TEST(RtpPacketizerH265Test, FuWithFirstPacketReduction) {
+  RtpPacketizer::PayloadSizeLimits limits;
+  limits.max_payload_len = 1200;
+  limits.first_packet_reduction_len = 4;
+  limits.single_packet_reduction_len = 4;
+  EXPECT_THAT(TestFu(1198, limits), ElementsAre(597, 601));
+}
+
+TEST(RtpPacketizerH265Test, FuWithLastPacketReduction) {
+  RtpPacketizer::PayloadSizeLimits limits;
+  limits.max_payload_len = 1200;
+  limits.last_packet_reduction_len = 4;
+  limits.single_packet_reduction_len = 4;
+  EXPECT_THAT(TestFu(1198, limits), ElementsAre(601, 597));
+}
+
+TEST(RtpPacketizerH265Test, FuWithSinglePacketReduction) {
+  RtpPacketizer::PayloadSizeLimits limits;
+  limits.max_payload_len = 1199;
+  limits.single_packet_reduction_len = 200;
+  EXPECT_THAT(TestFu(1000, limits), ElementsAre(500, 500));
+}
+
+TEST(RtpPacketizerH265Test, FuEvenSize) {
+  RtpPacketizer::PayloadSizeLimits limits;
+  limits.max_payload_len = 1200;
+  EXPECT_THAT(TestFu(1201, limits), ElementsAre(600, 601));
+}
+
+TEST(RtpPacketizerH265Test, FuRounding) {
+  RtpPacketizer::PayloadSizeLimits limits;
+  limits.max_payload_len = 1448;
+  EXPECT_THAT(TestFu(10123, limits),
+              ElementsAre(1265, 1265, 1265, 1265, 1265, 1266, 1266, 1266));
+}
+
+TEST(RtpPacketizerH265Test, FuBig) {
+  RtpPacketizer::PayloadSizeLimits limits;
+  limits.max_payload_len = 1200;
+  // Generate 10 full sized packets, leave room for FU headers.
+  EXPECT_THAT(
+      TestFu(10 * (1200 - kFuHeaderSize), limits),
+      ElementsAre(1197, 1197, 1197, 1197, 1197, 1197, 1197, 1197, 1197, 1197));
+}
+
+struct PacketInfo {
+  bool first_fragment = false;
+  bool last_fragment = false;
+  bool aggregated = false;
+  int nalu_index = 0;
+  int nalu_number = 0;
+  int payload_size = 0;
+  int start_offset = 0;
+};
+
+struct MixedApFuTestParams {
+  std::vector<int> nalus;
+  int expect_packetsSize = 0;
+  std::vector<PacketInfo> expected_packets;
+};
+
+class RtpPacketizerH265ParametrizedTest
+    : public ::testing::TestWithParam<MixedApFuTestParams> {};
+
+// Fragmentation + aggregation mixed testing.
+TEST_P(RtpPacketizerH265ParametrizedTest, MixedApFu) {
+  RtpPacketizer::PayloadSizeLimits limits;
+  const MixedApFuTestParams params = GetParam();
+  limits.max_payload_len = 100;
+  std::vector<rtc::Buffer> nalus;
+  nalus.reserve(params.nalus.size());
+
+  // Generate nalus according to size specified in paramters
+  for (size_t index = 0; index < params.nalus.size(); index++) {
+    nalus.push_back(GenerateNalUnit(params.nalus[index]));
+  }
+  rtc::Buffer frame = CreateFrame(nalus);
+
+  RtpPacketizerH265 packetizer(frame, limits);
+  std::vector<RtpPacketToSend> packets = FetchAllPackets(&packetizer);
+
+  ASSERT_THAT(packets, SizeIs(params.expect_packetsSize));
+  for (int i = 0; i < params.expect_packetsSize; i++) {
+    PacketInfo expected_packet = params.expected_packets[i];
+    if (expected_packet.aggregated) {
+      int type = H265::ParseNaluType(packets[i].payload()[0]);
+      EXPECT_THAT(type, H265::NaluType::kAp);
+      auto payload = packets[i].payload().subview(kNalHeaderSize);
+      int offset = 0;
+      // Generated AP packet header and payload align
+      for (int j = expected_packet.nalu_index; j < expected_packet.nalu_number;
+           j++) {
+        EXPECT_THAT(payload.subview(0, kLengthFieldLength),
+                    ElementsAre(0, nalus[j].size()));
+        EXPECT_THAT(
+            payload.subview(offset + kLengthFieldLength, nalus[j].size()),
+            ElementsAreArray(nalus[j]));
+        offset += kLengthFieldLength + nalus[j].size();
+      }
+    } else {
+      uint8_t fu_header = 0;
+      fu_header |= (expected_packet.first_fragment ? kH265SBit : 0);
+      fu_header |= (expected_packet.last_fragment ? kH265EBit : 0);
+      fu_header |= H265::NaluType::kTrailR;
+      EXPECT_THAT(packets[i].payload().subview(0, kFuHeaderSize),
+                  ElementsAre(98, 2, fu_header));
+      EXPECT_THAT(
+          packets[i].payload().subview(kFuHeaderSize),
+          ElementsAreArray(nalus[expected_packet.nalu_index].data() +
+                               kNalHeaderSize + expected_packet.start_offset,
+                           expected_packet.payload_size));
+    }
+  }
+}
+
+INSTANTIATE_TEST_SUITE_P(
+    RtpPacketizerH265Test,
+    RtpPacketizerH265ParametrizedTest,
+    testing::Values(
+        // FU + AP + FU.
+        // GenerateNalUnit will include 2 bytes nalu header, for FU packet split
+        // calculation, this 2-byte nalu header length should be excluded.
+        MixedApFuTestParams{.nalus = {140, 20, 20, 160},
+                            .expect_packetsSize = 5,
+                            .expected_packets = {{.first_fragment = true,
+                                                  .nalu_index = 0,
+                                                  .payload_size = 69,
+                                                  .start_offset = 0},
+                                                 {.last_fragment = true,
+                                                  .nalu_index = 0,
+                                                  .payload_size = 69,
+                                                  .start_offset = 69},
+                                                 {.aggregated = true,
+                                                  .nalu_index = 1,
+                                                  .nalu_number = 2},
+                                                 {.first_fragment = true,
+                                                  .nalu_index = 3,
+                                                  .payload_size = 79,
+                                                  .start_offset = 0},
+                                                 {.last_fragment = true,
+                                                  .nalu_index = 3,
+                                                  .payload_size = 79,
+                                                  .start_offset = 79}}},
+        // AP + FU + AP
+        MixedApFuTestParams{
+            .nalus = {20, 20, 160, 30, 30},
+            .expect_packetsSize = 4,
+            .expected_packets = {
+                {.aggregated = true, .nalu_index = 0, .nalu_number = 2},
+                {.first_fragment = true,
+                 .nalu_index = 2,
+                 .payload_size = 79,
+                 .start_offset = 0},
+                {.last_fragment = true,
+                 .nalu_index = 2,
+                 .payload_size = 79,
+                 .start_offset = 79},
+                {.aggregated = true, .nalu_index = 3, .nalu_number = 2}}}));
+
+}  // namespace
+}  // namespace webrtc