Convert Vp8 Rtp headers to frame references.

webrtc/modules/video_coding/packet_buffer_unittest.cc

Index: webrtc/modules/video_coding/packet_buffer_unittest.cc
diff --git a/webrtc/modules/video_coding/packet_buffer_unittest.cc b/webrtc/modules/video_coding/packet_buffer_unittest.cc
index bc06940391cda21a2f43e9cd4311ceeab6379d55..97bda36e73bd9408921b49d707f424612614ae8c 100644
--- a/webrtc/modules/video_coding/packet_buffer_unittest.cc
+++ b/webrtc/modules/video_coding/packet_buffer_unittest.cc
@@ -29,22 +29,105 @@ class TestPacketBuffer : public ::testing::Test,
   uint16_t Rand() { return rand_.Rand(std::numeric_limits<uint16_t>::max()); }
 
   void OnCompleteFrame(std::unique_ptr<FrameObject> frame) override {
-    frames_from_callback_.emplace_back(std::move(frame));
+    uint16_t pid = frame->picture_id;
+    auto frame_it = frames_from_callback_.find(pid);
+    if (frame_it != frames_from_callback_.end()) {
+      ADD_FAILURE() << "Already received frame with picture id: " << pid;
+      return;
+    }
+
+    frames_from_callback_.insert(
+        make_pair(frame->picture_id, std::move(frame)));
   }
 
   void TearDown() override {
-    // All FrameObjects must be destroyed before the PacketBuffer since
-    // a FrameObject will try to remove itself from the packet buffer
+    // All frame objects must be destroyed before the packet buffer since
+    // a frame object will try to remove itself from the packet buffer
     // upon destruction.
     frames_from_callback_.clear();
   }
 
+  // Insert a generic packet into the packet buffer.
+  void InsertGeneric(uint16_t seq_num,              // packet sequence number
+                     bool keyframe,                 // is keyframe
+                     bool first,                    // is first packet of frame
+                     bool last,                     // is last packet of frame
+                     size_t data_size = 0,          // size of data
+                     uint8_t* data = nullptr) {     // data pointer
+    VCMPacket packet;
+    packet.codec = kVideoCodecGeneric;
+    packet.seqNum = seq_num;
+    packet.frameType = keyframe ? kVideoFrameKey : kVideoFrameDelta;
+    packet.isFirstPacket = first;
+    packet.markerBit = last;
+    packet.sizeBytes = data_size;
+    packet.dataPtr = data;
+
+    EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
+  }
+
+  // Insert a Vp8 packet into the packet buffer.
+  void InsertVp8(uint16_t seq_num,              // packet sequence number
+                 bool keyframe,                 // is keyframe
+                 bool first,                    // is first packet of frame
+                 bool last,                     // is last packet of frame
+                 bool sync = false,             // is sync frame
+                 int32_t pid = kNoPictureId,    // picture id
+                 uint8_t tid = kNoTemporalIdx,  // temporal id
+                 int16_t tl0 = kNoTl0PicIdx,    // tl0 pic index
+                 size_t data_size = 0,          // size of data
+                 uint8_t* data = nullptr) {     // data pointer
+    VCMPacket packet;
+    packet.codec = kVideoCodecVP8;
+    packet.seqNum = seq_num;
+    packet.frameType = keyframe ? kVideoFrameKey : kVideoFrameDelta;
+    packet.isFirstPacket = first;
+    packet.markerBit = last;
+    packet.sizeBytes = data_size;
+    packet.dataPtr = data;
+    packet.codecSpecificHeader.codecHeader.VP8.pictureId = pid;
+    packet.codecSpecificHeader.codecHeader.VP8.temporalIdx = tid;
+    packet.codecSpecificHeader.codecHeader.VP8.tl0PicIdx = tl0;
+    packet.codecSpecificHeader.codecHeader.VP8.layerSync = sync;
+
+    EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
+  }
+
+  // Check if a frame with picture id |pid| has been delivered from the packet
+  // buffer, and if so, if it has the references specified by |refs|.
+  template <typename... T>
+  void CheckReferences(int16_t pid, T... refs) const {
+    auto frame_it = frames_from_callback_.find(pid);
+    if (frame_it == frames_from_callback_.end()) {
+      ADD_FAILURE() << "Could not find frame with picture id " << pid;
+      return;
+    }
+
+    std::set<uint16_t> actual_refs;
+    for (uint8_t r = 0; r < frame_it->second->num_references; ++r) {
+      actual_refs.insert(frame_it->second->references[r]);
+    }
+
+    std::set<uint16_t> expected_refs;
+    RefsToSet(&expected_refs, refs...);
+
+    ASSERT_EQ(expected_refs, actual_refs);
+  }
+
+  template <typename... T>
+  void RefsToSet(std::set<uint16_t>* m, uint16_t ref, T... refs) const {
+    m->insert(ref);
+    RefsToSet(m, refs...);
+  }
+
+  void RefsToSet(std::set<uint16_t>* m) const {}
+
   const int kStartSize = 16;
   const int kMaxSize = 64;
 
   Random rand_;
   PacketBuffer packet_buffer_;
-  std::vector<std::unique_ptr<FrameObject>> frames_from_callback_;
+  std::map<uint16_t, std::unique_ptr<FrameObject>> frames_from_callback_;
 };
 
 TEST_F(TestPacketBuffer, InsertOnePacket) {
@@ -70,96 +153,65 @@ TEST_F(TestPacketBuffer, InsertDuplicatePacket) {
   ++packet.seqNum;
   EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
   EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-  ++packet.seqNum;
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
 }
 
 TEST_F(TestPacketBuffer, ExpandBuffer) {
-  VCMPacket packet;
-  packet.seqNum = Rand();
+  uint16_t seq_num = Rand();
 
   for (int i = 0; i < kStartSize + 1; ++i) {
-    EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-    ++packet.seqNum;
+    //            seq_num    , keyframe, first, last
+    InsertGeneric(seq_num + i, true    , true , true);
   }
 }
 
 TEST_F(TestPacketBuffer, ExpandBufferOverflow) {
-  VCMPacket packet;
-  packet.seqNum = Rand();
+  uint16_t seq_num = Rand();
 
   for (int i = 0; i < kMaxSize; ++i) {
-    EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-    ++packet.seqNum;
+    //            seq_num    , keyframe, first, last
+    InsertGeneric(seq_num + i, true    , true , true);
   }
 
+  VCMPacket packet;
+  packet.seqNum = seq_num + kMaxSize + 1;
+  packet.sizeBytes = 1;
   EXPECT_FALSE(packet_buffer_.InsertPacket(packet));
 }
 
-TEST_F(TestPacketBuffer, OnePacketOneFrame) {
-  VCMPacket packet;
-  packet.isFirstPacket = true;
-  packet.markerBit = true;
-  packet.seqNum = Rand();
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-  EXPECT_EQ(1UL, frames_from_callback_.size());
+TEST_F(TestPacketBuffer, GenericOnePacketOneFrame) {
+  //            seq_num, keyframe, first, last
+  InsertGeneric(Rand() , true    , true , true);
+  ASSERT_EQ(1UL, frames_from_callback_.size());
 }
 
-TEST_F(TestPacketBuffer, TwoPacketsTwoFrames) {
-  VCMPacket packet;
-  packet.isFirstPacket = true;
-  packet.markerBit = true;
-  packet.seqNum = Rand();
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-  ++packet.seqNum;
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
+TEST_F(TestPacketBuffer, GenericTwoPacketsTwoFrames) {
+  uint16_t seq_num = Rand();
+
+  //            seq_num    , keyframe, first, last
+  InsertGeneric(seq_num    , true    , true , true);
+  InsertGeneric(seq_num + 1, true    , true , true);
+
   EXPECT_EQ(2UL, frames_from_callback_.size());
 }
 
-TEST_F(TestPacketBuffer, TwoPacketsOneFrames) {
-  VCMPacket packet;
-  packet.isFirstPacket = true;
-  packet.seqNum = Rand();
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-  packet.markerBit = true;
-  ++packet.seqNum;
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-  EXPECT_EQ(1UL, frames_from_callback_.size());
-}
+TEST_F(TestPacketBuffer, GenericTwoPacketsOneFrames) {
+  uint16_t seq_num = Rand();
+
+  //            seq_num    , keyframe, first, last
+  InsertGeneric(seq_num    , true    , true , false);
+  InsertGeneric(seq_num + 1, true    , false, true);
 
-TEST_F(TestPacketBuffer, ThreePacketReorderingOneFrame) {
-  VCMPacket packet;
-  packet.isFirstPacket = true;
-  packet.seqNum = Rand();
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-  EXPECT_EQ(0UL, frames_from_callback_.size());
-  packet.isFirstPacket = false;
-  packet.markerBit = true;
-  packet.seqNum += 2;
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-  EXPECT_EQ(0UL, frames_from_callback_.size());
-  packet.markerBit = false;
-  packet.seqNum -= 1;
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
   EXPECT_EQ(1UL, frames_from_callback_.size());
 }
 
-TEST_F(TestPacketBuffer, IndexWrapOneFrame) {
-  VCMPacket packet;
-  packet.isFirstPacket = true;
-  packet.seqNum = kStartSize - 1;
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-  EXPECT_EQ(0UL, frames_from_callback_.size());
-  packet.isFirstPacket = false;
-  ++packet.seqNum;
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-  EXPECT_EQ(0UL, frames_from_callback_.size());
-  ++packet.seqNum;
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-  EXPECT_EQ(0UL, frames_from_callback_.size());
-  packet.markerBit = true;
-  ++packet.seqNum;
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
+TEST_F(TestPacketBuffer, GenericThreePacketReorderingOneFrame) {
+  uint16_t seq_num = Rand();
+
+  //            seq_num    , keyframe, first, last
+  InsertGeneric(seq_num    , true    , true , false);
+  InsertGeneric(seq_num + 2, true    , false, true);
+  InsertGeneric(seq_num + 1, true    , false, false);
+
   EXPECT_EQ(1UL, frames_from_callback_.size());
 }
 
@@ -216,81 +268,61 @@ TEST_F(TestPacketBuffer, GetBitstreamFromFrame) {
   uint8_t
       result[sizeof(many) + sizeof(bitstream) + sizeof(such) + sizeof(data)];
 
-  VCMPacket packet;
-  packet.isFirstPacket = true;
-  packet.seqNum = 0xfffe;
-  packet.dataPtr = many;
-  packet.sizeBytes = sizeof(many);
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-  packet.isFirstPacket = false;
-  ++packet.seqNum;
-  packet.dataPtr = bitstream;
-  packet.sizeBytes = sizeof(bitstream);
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-  ++packet.seqNum;
-  packet.dataPtr = such;
-  packet.sizeBytes = sizeof(such);
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-  packet.markerBit = true;
-  ++packet.seqNum;
-  packet.dataPtr = data;
-  packet.sizeBytes = sizeof(data);
-  EXPECT_EQ(0UL, frames_from_callback_.size());
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-  ASSERT_EQ(1UL, frames_from_callback_.size());
+  uint16_t seq_num = Rand();
+
+  //            seq_num    , keyf , first, last , data_size        , data
+  InsertGeneric(seq_num    , true , true , false, sizeof(many)     , many);
+  InsertGeneric(seq_num + 1, false, false, false, sizeof(bitstream), bitstream);
+  InsertGeneric(seq_num + 2, false, false, false, sizeof(such)     , such);
+  InsertGeneric(seq_num + 3, false, false, true , sizeof(data)     , data);
 
-  EXPECT_TRUE(frames_from_callback_[0]->GetBitstream(result));
-  EXPECT_EQ(
-      std::strcmp("many bitstream, such data", reinterpret_cast<char*>(result)),
-      0);
+  ASSERT_EQ(1UL, frames_from_callback_.size());
+  CheckReferences(seq_num + 3);
+  EXPECT_TRUE(frames_from_callback_[seq_num + 3]->GetBitstream(result));
+  EXPECT_EQ(std::strcmp("many bitstream, such data",
+            reinterpret_cast<char*>(result)),
+            0);
 }
 
 TEST_F(TestPacketBuffer, FreeSlotsOnFrameDestruction) {
-  VCMPacket packet;
-  packet.isFirstPacket = true;
-  packet.seqNum = Rand();
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-  EXPECT_EQ(0UL, frames_from_callback_.size());
-  packet.isFirstPacket = false;
-  ++packet.seqNum;
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-  EXPECT_EQ(0UL, frames_from_callback_.size());
-  ++packet.seqNum;
-  packet.markerBit = true;
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
+  uint16_t seq_num = Rand();
+
+  //            seq_num    , keyf , first, last
+  InsertGeneric(seq_num    , true , true , false);
+  InsertGeneric(seq_num + 1, false, false, false);
+  InsertGeneric(seq_num + 2, false, false, true);
   EXPECT_EQ(1UL, frames_from_callback_.size());
 
   frames_from_callback_.clear();
 
-  packet.isFirstPacket = true;
-  packet.markerBit = false;
-  packet.seqNum = Rand();
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-  EXPECT_EQ(0UL, frames_from_callback_.size());
-  packet.isFirstPacket = false;
-  ++packet.seqNum;
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-  EXPECT_EQ(0UL, frames_from_callback_.size());
-  ++packet.seqNum;
-  packet.markerBit = true;
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
+  //            seq_num    , keyf , first, last
+  InsertGeneric(seq_num    , true , true , false);
+  InsertGeneric(seq_num + 1, false, false, false);
+  InsertGeneric(seq_num + 2, false, false, true);
   EXPECT_EQ(1UL, frames_from_callback_.size());
 }
 
 TEST_F(TestPacketBuffer, Flush) {
-  VCMPacket packet;
-  packet.isFirstPacket = true;
-  packet.markerBit = true;
-  packet.seqNum = Rand();
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
+  uint16_t seq_num = Rand();
+
+  //            seq_num    , keyf , first, last
+  InsertGeneric(seq_num    , true , true , false);
+  InsertGeneric(seq_num + 1, false, false, false);
+  InsertGeneric(seq_num + 2, false, false, true);
+  EXPECT_EQ(1UL, frames_from_callback_.size());
+
   packet_buffer_.Flush();
-  EXPECT_TRUE(packet_buffer_.InsertPacket(packet));
+
+  //            seq_num                 , keyf , first, last
+  InsertGeneric(seq_num + kStartSize    , true , true , false);
+  InsertGeneric(seq_num + kStartSize + 1, false, false, false);
+  InsertGeneric(seq_num + kStartSize + 2, false, false, true);
   EXPECT_EQ(2UL, frames_from_callback_.size());
 }
 
 TEST_F(TestPacketBuffer, InvalidateFrameByFlushing) {
   VCMPacket packet;
+  packet.frameType = kVideoFrameKey;
   packet.isFirstPacket = true;
   packet.markerBit = true;
   packet.seqNum = Rand();
@@ -298,7 +330,300 @@ TEST_F(TestPacketBuffer, InvalidateFrameByFlushing) {
   ASSERT_EQ(1UL, frames_from_callback_.size());
 
   packet_buffer_.Flush();
-  EXPECT_FALSE(frames_from_callback_[0]->GetBitstream(nullptr));
+  EXPECT_FALSE(frames_from_callback_.begin()->second->GetBitstream(nullptr));
+}
+
+TEST_F(TestPacketBuffer, Vp8NoPictureId) {
+  uint16_t seq_num = Rand();
+
+  //        seq_num     , keyf , first, last
+  InsertVp8(seq_num     , true , true , false);
+  InsertVp8(seq_num + 1 , false, false, false);
+  InsertVp8(seq_num + 2 , false, false, true);
+  ASSERT_EQ(1UL, frames_from_callback_.size());
+
+  InsertVp8(seq_num + 3 , false, true , false);
+  InsertVp8(seq_num + 4 , false, false, true);
+  ASSERT_EQ(2UL, frames_from_callback_.size());
+
+  InsertVp8(seq_num + 5 , false, true , false);
+  InsertVp8(seq_num + 6 , false, false, false);
+  InsertVp8(seq_num + 7 , false, false, false);
+  InsertVp8(seq_num + 8 , false, false, true);
+  ASSERT_EQ(3UL, frames_from_callback_.size());
+
+  InsertVp8(seq_num + 9 , false, true , true);
+  ASSERT_EQ(4UL, frames_from_callback_.size());
+
+  InsertVp8(seq_num + 10, false, true , false);
+  InsertVp8(seq_num + 11, false, false, true);
+  ASSERT_EQ(5UL, frames_from_callback_.size());
+
+  InsertVp8(seq_num + 12, true , true , true);
+  ASSERT_EQ(6UL, frames_from_callback_.size());
+
+  InsertVp8(seq_num + 13, false, true , false);
+  InsertVp8(seq_num + 14, false, false, false);
+  InsertVp8(seq_num + 15, false, false, false);
+  InsertVp8(seq_num + 16, false, false, false);
+  InsertVp8(seq_num + 17, false, false, true);
+  ASSERT_EQ(7UL, frames_from_callback_.size());
+
+  InsertVp8(seq_num + 18, false, true , true);
+  ASSERT_EQ(8UL, frames_from_callback_.size());
+
+  InsertVp8(seq_num + 19, false, true , false);
+  InsertVp8(seq_num + 20, false, false, true);
+  ASSERT_EQ(9UL, frames_from_callback_.size());
+
+  InsertVp8(seq_num + 21, false, true , true);
+
+  ASSERT_EQ(10UL, frames_from_callback_.size());
+  CheckReferences(seq_num + 2);
+  CheckReferences(seq_num + 4, seq_num + 2);
+  CheckReferences(seq_num + 8, seq_num + 4);
+  CheckReferences(seq_num + 9, seq_num + 8);
+  CheckReferences(seq_num + 11, seq_num + 9);
+  CheckReferences(seq_num + 12);
+  CheckReferences(seq_num + 17, seq_num + 12);
+  CheckReferences(seq_num + 18, seq_num + 17);
+  CheckReferences(seq_num + 20, seq_num + 18);
+  CheckReferences(seq_num + 21, seq_num + 20);
+}
+
+TEST_F(TestPacketBuffer, Vp8NoPictureIdReordered) {
+  uint16_t seq_num = 0xfffa;
+
+  //        seq_num     , keyf , first, last
+  InsertVp8(seq_num + 1 , false, false, false);
+  InsertVp8(seq_num     , true , true , false);
+  InsertVp8(seq_num + 2 , false, false, true);
+  InsertVp8(seq_num + 4 , false, false, true);
+  InsertVp8(seq_num + 6 , false, false, false);
+  InsertVp8(seq_num + 3 , false, true , false);
+  InsertVp8(seq_num + 7 , false, false, false);
+  InsertVp8(seq_num + 5 , false, true , false);
+  InsertVp8(seq_num + 9 , false, true , true);
+  InsertVp8(seq_num + 10, false, true , false);
+  InsertVp8(seq_num + 8 , false, false, true);
+  InsertVp8(seq_num + 13, false, true , false);
+  InsertVp8(seq_num + 14, false, false, false);
+  InsertVp8(seq_num + 12, true , true , true);
+  InsertVp8(seq_num + 11, false, false, true);
+  InsertVp8(seq_num + 16, false, false, false);
+  InsertVp8(seq_num + 19, false, true , false);
+  InsertVp8(seq_num + 15, false, false, false);
+  InsertVp8(seq_num + 17, false, false, true);
+  InsertVp8(seq_num + 20, false, false, true);
+  InsertVp8(seq_num + 21, false, true , true);
+  InsertVp8(seq_num + 18, false, true , true);
+
+  ASSERT_EQ(10UL, frames_from_callback_.size());
+  CheckReferences(seq_num + 2);
+  CheckReferences(seq_num + 4, seq_num + 2);
+  CheckReferences(seq_num + 8, seq_num + 4);
+  CheckReferences(seq_num + 9, seq_num + 8);
+  CheckReferences(seq_num + 11, seq_num + 9);
+  CheckReferences(seq_num + 12);
+  CheckReferences(seq_num + 17, seq_num + 12);
+  CheckReferences(seq_num + 18, seq_num + 17);
+  CheckReferences(seq_num + 20, seq_num + 18);
+  CheckReferences(seq_num + 21, seq_num + 20);
+}
+
+
+TEST_F(TestPacketBuffer, Vp8KeyFrameReferences) {
+  uint16_t pid = Rand();
+  //        seq_num, keyf, first, last, sync , pid, tid, tl0
+  InsertVp8(Rand() , true, true , true, false, pid, 0  , 0);
+
+  ASSERT_EQ(1UL, frames_from_callback_.size());
+  CheckReferences(pid % PacketBuffer::kPicIdLength);
+}
+
+TEST_F(TestPacketBuffer, Vp8TemporalLayers_0) {
+  uint16_t pid = Rand();
+  uint16_t seq_num = Rand();
+
+  //        seq_num    , keyf , first, last, sync , pid    , tid, tl0
+  InsertVp8(seq_num    , true , true , true, false, pid    , 0  , 1);
+  InsertVp8(seq_num + 1, false, true , true, false, pid + 1, 0  , 2);
+  InsertVp8(seq_num + 2, false, true , true, false, pid + 2, 0  , 3);
+  InsertVp8(seq_num + 3, false, true , true, false, pid + 3, 0  , 4);
+
+  ASSERT_EQ(4UL, frames_from_callback_.size());
+  pid = pid % PacketBuffer::kPicIdLength;
+  CheckReferences(pid);
+  CheckReferences(pid + 1, pid);
+  CheckReferences(pid + 2, pid + 1);
+  CheckReferences(pid + 3, pid + 2);
+}
+
+TEST_F(TestPacketBuffer, Vp8TemporalLayersReordering_0) {
+  uint16_t pid = Rand();
+  uint16_t seq_num = Rand();
+
+  //        seq_num    , keyf , first, last, sync , pid    , tid, tl0
+  InsertVp8(seq_num    , true , true , true, false, pid    , 0  , 1);
+  InsertVp8(seq_num + 1, false, true , true, false, pid + 1, 0  , 2);
+  InsertVp8(seq_num + 3, false, true , true, false, pid + 3, 0  , 4);
+  InsertVp8(seq_num + 2, false, true , true, false, pid + 2, 0  , 3);
+  InsertVp8(seq_num + 5, false, true , true, false, pid + 5, 0  , 6);
+  InsertVp8(seq_num + 6, false, true , true, false, pid + 6, 0  , 7);
+  InsertVp8(seq_num + 4, false, true , true, false, pid + 4, 0  , 5);
+
+  ASSERT_EQ(7UL, frames_from_callback_.size());
+  pid = pid % PacketBuffer::kPicIdLength;
+  CheckReferences(pid);
+  CheckReferences(pid + 1, pid);
+  CheckReferences(pid + 2, pid + 1);
+  CheckReferences(pid + 3, pid + 2);
+  CheckReferences(pid + 4, pid + 3);
+  CheckReferences(pid + 5, pid + 4);
+  CheckReferences(pid + 6, pid + 5);
+}
+
+TEST_F(TestPacketBuffer, Vp8TemporalLayers_01) {
+  uint16_t pid = Rand();
+  uint16_t seq_num = Rand();
+
+  //        seq_num    , keyf , first, last, sync , pid    , tid, tl0
+  InsertVp8(seq_num    , true , true , true, false, pid    , 0, 255);
+  InsertVp8(seq_num + 1, false, true , true, true , pid + 1, 1, 255);
+  InsertVp8(seq_num + 2, false, true , true, false, pid + 2, 0, 0);
+  InsertVp8(seq_num + 3, false, true , true, false, pid + 3, 1, 0);
+
+  ASSERT_EQ(4UL, frames_from_callback_.size());
+  pid = pid % PacketBuffer::kPicIdLength;
+  CheckReferences(pid);
+  CheckReferences(pid + 1, pid);
+  CheckReferences(pid + 2, pid);
+  CheckReferences(pid + 3, pid + 1, pid + 2);
+}
+
+TEST_F(TestPacketBuffer, Vp8TemporalLayersReordering_01) {
+  uint16_t pid = Rand();
+  uint16_t seq_num = Rand();
+
+  //        seq_num    , keyf , first, last, sync , pid    , tid, tl0
+  InsertVp8(seq_num + 1, false, true , true, true , pid + 1, 1  , 255);
+  InsertVp8(seq_num    , true , true , true, false, pid    , 0  , 255);
+  InsertVp8(seq_num + 3, false, true , true, false, pid + 3, 1  , 0);
+  InsertVp8(seq_num + 5, false, true , true, false, pid + 5, 1  , 1);
+  InsertVp8(seq_num + 2, false, true , true, false, pid + 2, 0  , 0);
+  InsertVp8(seq_num + 4, false, true , true, false, pid + 4, 0  , 1);
+  InsertVp8(seq_num + 6, false, true , true, false, pid + 6, 0  , 2);
+  InsertVp8(seq_num + 7, false, true , true, false, pid + 7, 1  , 2);
+
+  ASSERT_EQ(8UL, frames_from_callback_.size());
+  pid = pid % PacketBuffer::kPicIdLength;
+  CheckReferences(pid);
+  CheckReferences(pid + 1, pid);
+  CheckReferences(pid + 2, pid);
+  CheckReferences(pid + 3, pid + 1, pid + 2);
+  CheckReferences(pid + 4, pid + 2);
+  CheckReferences(pid + 5, pid + 3, pid + 4);
+  CheckReferences(pid + 6, pid + 4);
+  CheckReferences(pid + 7, pid + 5, pid + 6);
+}
+
+TEST_F(TestPacketBuffer, Vp8TemporalLayers_0212) {

[pbos-webrtc, 2016/04/01 14:24:45]

Can you put some comments on what these are doing specifically? I find _0212
hard to read since I'm less familiar with this part.

[philipel, 2016/04/05 12:40:50]

Done.

+  uint16_t pid = Rand();
+  uint16_t seq_num = Rand();
+
+  //        seq_num     , keyf , first, last, sync , pid    , tid, tl0
+  InsertVp8(seq_num     , true , true , true , false, pid     , 0  , 55);
+  InsertVp8(seq_num + 1 , false, true , true , true , pid + 1 , 2  , 55);
+  InsertVp8(seq_num + 2 , false, true , true , true , pid + 2 , 1  , 55);
+  InsertVp8(seq_num + 3 , false, true , true , false, pid + 3 , 2  , 55);
+  InsertVp8(seq_num + 4 , false, true , true , false, pid + 4 , 0  , 56);
+  InsertVp8(seq_num + 5 , false, true , true , false, pid + 5 , 2  , 56);
+  InsertVp8(seq_num + 6 , false, true , true , false, pid + 6 , 1  , 56);
+  InsertVp8(seq_num + 7 , false, true , true , false, pid + 7 , 2  , 56);
+  InsertVp8(seq_num + 8 , false, true , true , false, pid + 8 , 0  , 57);
+  InsertVp8(seq_num + 9 , false, true , true , true , pid + 9 , 2  , 57);
+  InsertVp8(seq_num + 10, false, true , true , true , pid + 10, 1  , 57);
+  InsertVp8(seq_num + 11, false, true , true , false, pid + 11, 2  , 57);
+
+  ASSERT_EQ(12UL, frames_from_callback_.size());
+  pid = pid % PacketBuffer::kPicIdLength;
+  CheckReferences(pid);
+  CheckReferences(pid + 1 , pid);
+  CheckReferences(pid + 2 , pid);
+  CheckReferences(pid + 3 , pid, pid + 1, pid + 2);
+  CheckReferences(pid + 4 , pid);
+  CheckReferences(pid + 5 , pid + 2, pid + 3, pid + 4);
+  CheckReferences(pid + 6 , pid + 2, pid + 4);
+  CheckReferences(pid + 7 , pid + 4, pid + 5, pid + 6);
+  CheckReferences(pid + 8 , pid + 4);
+  CheckReferences(pid + 9 , pid + 8);
+  CheckReferences(pid + 10, pid + 8);
+  CheckReferences(pid + 11, pid + 8, pid + 9, pid + 10);
+}
+
+TEST_F(TestPacketBuffer, Vp8TemporalLayersReordering_0212) {
+  uint16_t pid = 126;
+  uint16_t seq_num = Rand();
+
+  //        seq_num     , keyf , first, last, sync , pid     , tid, tl0
+  InsertVp8(seq_num + 1 , false, true , true, true , pid + 1 , 2  , 55);
+  ASSERT_EQ(0UL, frames_from_callback_.size());
+  InsertVp8(seq_num     , true , true , true, false, pid     , 0  , 55);
+  ASSERT_EQ(2UL, frames_from_callback_.size());
+  InsertVp8(seq_num + 2 , false, true , true, true , pid + 2 , 1  , 55);
+  ASSERT_EQ(3UL, frames_from_callback_.size());
+  InsertVp8(seq_num + 4 , false, true , true, false, pid + 4 , 0  , 56);
+  InsertVp8(seq_num + 5 , false, true , true, false, pid + 5 , 2  , 56);
+  ASSERT_EQ(4UL, frames_from_callback_.size());
+  InsertVp8(seq_num + 3 , false, true , true, false, pid + 3 , 2  , 55);
+  ASSERT_EQ(6UL, frames_from_callback_.size());
+  InsertVp8(seq_num + 7 , false, true , true, false, pid + 7 , 2  , 56);
+  InsertVp8(seq_num + 9 , false, true , true, true , pid + 9 , 2  , 57);
+  InsertVp8(seq_num + 6 , false, true , true, false, pid + 6 , 1  , 56);
+  InsertVp8(seq_num + 8 , false, true , true, false, pid + 8 , 0  , 57);
+  InsertVp8(seq_num + 11, false, true , true, false, pid + 11, 2  , 57);
+  InsertVp8(seq_num + 10, false, true , true, true , pid + 10, 1  , 57);
+
+  ASSERT_EQ(12UL, frames_from_callback_.size());
+  pid = pid % PacketBuffer::kPicIdLength;
+  CheckReferences(pid);
+  CheckReferences(pid + 1 , pid);
+  CheckReferences(pid + 2 , pid);
+  CheckReferences(pid + 3 , pid, pid + 1, pid + 2);
+  CheckReferences(pid + 4 , pid);
+  CheckReferences(pid + 5 , pid + 2, pid + 3, pid + 4);
+  CheckReferences(pid + 6 , pid + 2, pid + 4);
+  CheckReferences(pid + 7 , pid + 4, pid + 5, pid + 6);
+  CheckReferences(pid + 8 , pid + 4);
+  CheckReferences(pid + 9 , pid + 8);
+  CheckReferences(pid + 10, pid + 8);
+  CheckReferences(pid + 11, pid + 8, pid + 9, pid + 10);
+}
+
+TEST_F(TestPacketBuffer, Vp8LayerSync) {
+  uint16_t pid = Rand();
+  uint16_t seq_num = Rand();
+
+  //        seq_num     , keyf , first, last, sync , pid     , tid, tl0
+  InsertVp8(seq_num     , true , true , true, false, pid     , 0  , 0);
+  InsertVp8(seq_num + 1 , false, true , true, true , pid + 1 , 1  , 0);
+  InsertVp8(seq_num + 2 , false, true , true, false, pid + 2 , 0  , 1);
+  ASSERT_EQ(3UL, frames_from_callback_.size());
+
+  InsertVp8(seq_num + 4 , false, true , true, false, pid + 4 , 0  , 2);
+  InsertVp8(seq_num + 5 , false, true , true, true , pid + 5 , 1  , 2);
+  InsertVp8(seq_num + 6 , false, true , true, false, pid + 6 , 0  , 3);
+  InsertVp8(seq_num + 7 , false, true , true, false, pid + 7 , 1  , 3);
+
+  ASSERT_EQ(7UL, frames_from_callback_.size());
+  pid = pid % PacketBuffer::kPicIdLength;
+  CheckReferences(pid);
+  CheckReferences(pid + 1, pid);
+  CheckReferences(pid + 2, pid);
+  CheckReferences(pid + 4, pid + 2);
+  CheckReferences(pid + 5, pid + 4);
+  CheckReferences(pid + 6, pid + 4);
+  CheckReferences(pid + 7, pid + 6, pid + 5);
 }
 
 }  // namespace video_coding