More Simulation Framework features

webrtc/modules/remote_bitrate_estimator/test/bwe_unittest.cc

+/*
+ *  Copyright (c) 2015 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 "webrtc/modules/remote_bitrate_estimator/test/bwe.h"
+
+#include <vector>
+
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace webrtc {
+namespace testing {
+namespace bwe {
+
+const int kSetCapacity = 1000;
+
+class LinkedSetTest : public ::testing::Test {
+ public:
+  LinkedSetTest() : linked_set_(kSetCapacity) {}
+
+  ~LinkedSetTest() {}
+
+ protected:
+  LinkedSet linked_set_;
+};
+
+TEST_F(LinkedSetTest, EmptySet) {
+  EXPECT_EQ(linked_set_.OldestSeqNumber(), 0);
+  EXPECT_EQ(linked_set_.NewestSeqNumber(), 0);
+}
+
+TEST_F(LinkedSetTest, SinglePacket) {
+  const uint16_t kSeqNumber = 1;  // Arbitrary.
+  // Other parameters don't matter here.
+  linked_set_.Insert(kSeqNumber, 0, 0, 0);
+
+  EXPECT_EQ(linked_set_.OldestSeqNumber(), kSeqNumber);
+  EXPECT_EQ(linked_set_.NewestSeqNumber(), kSeqNumber);
+}
+
+TEST_F(LinkedSetTest, MultiplePackets) {
+  const uint16_t kNumberPackets = 100;
+
+  std::vector<uint16_t> sequence_numbers;
+  for (size_t i = 0; i < kNumberPackets; ++i) {
+    sequence_numbers.push_back(static_cast<uint16_t>(i + 1));
+  }
+  random_shuffle(sequence_numbers.begin(), sequence_numbers.end());
+
+  for (size_t i = 0; i < kNumberPackets; ++i) {
+    // Other parameters don't matter here.
+    linked_set_.Insert(static_cast<uint16_t>(i), 0, 0, 0);
+  }
+
+  // Packets arriving out of order should not affect the following values:
+  EXPECT_EQ(linked_set_.OldestSeqNumber(), 0);
+  EXPECT_EQ(linked_set_.NewestSeqNumber(), kNumberPackets - 1);
+}
+
+TEST_F(LinkedSetTest, Overflow) {
+  const int kFirstSeqNumber = -100;
+  const int kLastSeqNumber = 100;
+
+  for (int i = kFirstSeqNumber; i <= kLastSeqNumber; ++i) {
+    // Other parameters don't matter here.
+    linked_set_.Insert(static_cast<uint16_t>(i), 0, 0, 0);
+  }
+
+  // Packets arriving out of order should not affect the following values:
+  EXPECT_EQ(linked_set_.OldestSeqNumber(),
+            static_cast<uint16_t>(kFirstSeqNumber));
+  EXPECT_EQ(linked_set_.NewestSeqNumber(),
+            static_cast<uint16_t>(kLastSeqNumber));
+}
+
+class SequenceNumberOlderThanTest : public ::testing::Test {
+ public:
+  SequenceNumberOlderThanTest() {}
+  ~SequenceNumberOlderThanTest() {}
+
+ protected:
+  SequenceNumberOlderThan comparator_;
+};
+
+TEST_F(SequenceNumberOlderThanTest, Operator) {
+  // Operator()(x, y) returns true <==> y is newer than x.
+  EXPECT_TRUE(comparator_.operator()(0x0000, 0x0001));
+  EXPECT_TRUE(comparator_.operator()(0x0001, 0x1000));
+  EXPECT_FALSE(comparator_.operator()(0x0001, 0x0000));
+  EXPECT_FALSE(comparator_.operator()(0x0002, 0x0002));
+  EXPECT_TRUE(comparator_.operator()(0xFFF6, 0x000A));
+  EXPECT_FALSE(comparator_.operator()(0x000A, 0xFFF6));
+  EXPECT_TRUE(comparator_.operator()(0x0000, 0x8000));
+  EXPECT_FALSE(comparator_.operator()(0x8000, 0x0000));
+}
+
+class LossAccountTest : public ::testing::Test {
+ public:
+  LossAccountTest() {}
+  ~LossAccountTest() {}
+
+ protected:
+  LossAccount loss_account_;
+};
+
+TEST_F(LossAccountTest, Operations) {
+  const size_t kTotal = 100;  // Arbitrary values.
+  const size_t kLost = 10;
+
+  LossAccount rhs(kTotal, kLost);
+
+  loss_account_.Add(rhs);
+  EXPECT_EQ(loss_account_.num_total, kTotal);
+  EXPECT_EQ(loss_account_.num_lost, kLost);
+  EXPECT_NEAR(loss_account_.LossRatio(), static_cast<float>(kLost) / kTotal,
+              0.001f);
+
+  loss_account_.Subtract(rhs);
+  EXPECT_EQ(loss_account_.num_total, 0UL);
+  EXPECT_EQ(loss_account_.num_lost, 0UL);
+  EXPECT_NEAR(loss_account_.LossRatio(), 0.0f, 0.001f);
+}
+
+class BweReceiverTest : public ::testing::Test {
+ public:
+  BweReceiverTest() : bwe_receiver_(kFlowId) {}
+  ~BweReceiverTest() {}
+
+ protected:
+  const int kFlowId = 1;  // Arbitrary.
+  BweReceiver bwe_receiver_;
+};
+
+TEST_F(BweReceiverTest, ReceivingRateNoPackets) {
+  EXPECT_EQ(bwe_receiver_.RecentKbps(), static_cast<size_t>(0));
+}
+
+TEST_F(BweReceiverTest, ReceivingRateSinglePacket) {
+  const size_t kPayloadSizeBytes = 500 * 1000;
+  const int64_t kSendTimeUs = 300 * 1000;
+  const int64_t kArrivalTimeMs = kSendTimeUs / 1000 + 100;
+  const uint16_t kSequenceNumber = 1;
+  const int64_t kTimeWindowMs = BweReceiver::kReceivingRateTimeWindowMs;
+
+  const MediaPacket media_packet(kFlowId, kSendTimeUs, kPayloadSizeBytes,
+                                 kSequenceNumber);
+  bwe_receiver_.ReceivePacket(kArrivalTimeMs, media_packet);
+
+  const size_t kReceivingRateKbps = 8 * kPayloadSizeBytes / kTimeWindowMs;
+
+  EXPECT_NEAR(bwe_receiver_.RecentKbps(), kReceivingRateKbps,
+              static_cast<float>(kReceivingRateKbps) / 100.0f);
+}
+
+TEST_F(BweReceiverTest, ReceivingRateSmallPackets) {
+  const size_t kPayloadSizeBytes = 100 * 1000;
+  const int64_t kTimeGapMs = 50;  // Between each packet.
+  const int64_t kOneWayDelayMs = 50;
+
+  for (int i = 1; i < 50; ++i) {
+    int64_t send_time_us = i * kTimeGapMs * 1000;
+    int64_t arrival_time_ms = send_time_us / 1000 + kOneWayDelayMs;
+    uint16_t sequence_number = i;
+    const MediaPacket media_packet(kFlowId, send_time_us, kPayloadSizeBytes,
+                                   sequence_number);
+    bwe_receiver_.ReceivePacket(arrival_time_ms, media_packet);
+  }
+
+  const size_t kReceivingRateKbps = 8 * kPayloadSizeBytes / kTimeGapMs;
+  EXPECT_NEAR(bwe_receiver_.RecentKbps(), kReceivingRateKbps,
+              static_cast<float>(kReceivingRateKbps) / 100.0f);
+}
+
+TEST_F(BweReceiverTest, PacketLossNoPackets) {
+  EXPECT_EQ(bwe_receiver_.RecentPacketLossRatio(), 0.0f);
+}
+
+TEST_F(BweReceiverTest, PacketLossSinglePacket) {
+  const MediaPacket media_packet(kFlowId, 0, 0, 0);
+  bwe_receiver_.ReceivePacket(0, media_packet);
+  EXPECT_EQ(bwe_receiver_.RecentPacketLossRatio(), 0.0f);
+}
+
+TEST_F(BweReceiverTest, PacketLossContiguousPackets) {
+  const int64_t kTimeWindowMs = BweReceiver::kPacketLossTimeWindowMs;
+  size_t set_capacity = bwe_receiver_.GetSetCapacity();
+
+  for (int i = 0; i < 10; ++i) {
+    uint16_t sequence_number = static_cast<uint16_t>(i);
+    // Sequence_number and flow_id are the only members that matter here.
+    const MediaPacket media_packet(kFlowId, 0, 0, sequence_number);
+    // Arrival time = 0, all packets will be considered.
+    bwe_receiver_.ReceivePacket(0, media_packet);
+  }
+  EXPECT_EQ(bwe_receiver_.RecentPacketLossRatio(), 0.0f);
+
+  for (int i = 30; i > 20; i--) {
+    uint16_t sequence_number = static_cast<uint16_t>(i);
+    // Sequence_number and flow_id are the only members that matter here.
+    const MediaPacket media_packet(kFlowId, 0, 0, sequence_number);
+    // Only the packets sent in this for loop will be considered.
+    bwe_receiver_.ReceivePacket(2 * kTimeWindowMs, media_packet);
+  }
+  EXPECT_EQ(bwe_receiver_.RecentPacketLossRatio(), 0.0f);
+
+  // Should handle uint16_t overflow.
+  for (int i = 0xFFFF - 10; i < 0xFFFF + 10; ++i) {
+    uint16_t sequence_number = static_cast<uint16_t>(i);
+    const MediaPacket media_packet(kFlowId, 0, 0, sequence_number);
+    // Only the packets sent in this for loop will be considered.
+    bwe_receiver_.ReceivePacket(4 * kTimeWindowMs, media_packet);
+  }
+  EXPECT_EQ(bwe_receiver_.RecentPacketLossRatio(), 0.0f);
+
+  // Should handle set overflow.
+  for (int i = 0; i < set_capacity * 1.5; ++i) {
+    uint16_t sequence_number = static_cast<uint16_t>(i);
+    const MediaPacket media_packet(kFlowId, 0, 0, sequence_number);
+    // Only the packets sent in this for loop will be considered.
+    bwe_receiver_.ReceivePacket(6 * kTimeWindowMs, media_packet);
+  }
+  EXPECT_EQ(bwe_receiver_.RecentPacketLossRatio(), 0.0f);
+}
+
+// Should handle duplicates.
+TEST_F(BweReceiverTest, PacketLossDuplicatedPackets) {
+  const int64_t kTimeWindowMs = BweReceiver::kPacketLossTimeWindowMs;
+
+  for (int i = 0; i < 10; ++i) {
+    const MediaPacket media_packet(kFlowId, 0, 0, 0);
+    // Arrival time = 0, all packets will be considered.
+    bwe_receiver_.ReceivePacket(0, media_packet);
+  }
+  EXPECT_EQ(bwe_receiver_.RecentPacketLossRatio(), 0.0f);
+
+  // Missing the element 5.
+  const uint16_t kSequenceNumbers[] = {1, 2, 3, 4, 6, 7, 8};
+  const int kNumPackets = ARRAY_SIZE(kSequenceNumbers);
+
+  // Insert each sequence number twice.
+  for (int i = 0; i < 2; ++i) {
+    for (int j = 0; j < kNumPackets; j++) {
+      const MediaPacket media_packet(kFlowId, 0, 0, kSequenceNumbers[j]);
+      // Only the packets sent in this for loop will be considered.
+      bwe_receiver_.ReceivePacket(2 * kTimeWindowMs, media_packet);
+    }
+  }
+
+  EXPECT_NEAR(bwe_receiver_.RecentPacketLossRatio(), 1.0f / (kNumPackets + 1),
+              0.1f / (kNumPackets + 1));
+}
+
+TEST_F(BweReceiverTest, PacketLossLakingPackets) {
+  size_t set_capacity = bwe_receiver_.GetSetCapacity();
+  EXPECT_LT(set_capacity, static_cast<size_t>(0xFFFF));
+
+  // Missing every other packet.
+  for (size_t i = 0; i < set_capacity; ++i) {
+    if ((i & 1) == 0) {  // Only even sequence numbers.
+      uint16_t sequence_number = static_cast<uint16_t>(i);
+      const MediaPacket media_packet(kFlowId, 0, 0, sequence_number);
+      // Arrival time = 0, all packets will be considered.
+      bwe_receiver_.ReceivePacket(0, media_packet);
+    }
+  }
+  EXPECT_NEAR(bwe_receiver_.RecentPacketLossRatio(), 0.5f, 0.01f);
+}
+
+TEST_F(BweReceiverTest, PacketLossLakingFewPackets) {
+  size_t set_capacity = bwe_receiver_.GetSetCapacity();
+  EXPECT_LT(set_capacity, static_cast<size_t>(0xFFFF));
+
+  const int kPeriod = 100;
+  // Missing one for each kPeriod packets.
+  for (size_t i = 0; i < set_capacity; ++i) {
+    if ((i % kPeriod) != 0) {
+      uint16_t sequence_number = static_cast<uint16_t>(i);
+      const MediaPacket media_packet(kFlowId, 0, 0, sequence_number);
+      // Arrival time = 0, all packets will be considered.
+      bwe_receiver_.ReceivePacket(0, media_packet);
+    }
+  }
+  EXPECT_NEAR(bwe_receiver_.RecentPacketLossRatio(), 1.0f / kPeriod,
+              0.1f / kPeriod);
+}
+
+// Packet's sequence numbers greatly apart, expect high loss.
+TEST_F(BweReceiverTest, PacketLossWideGap) {
+  const int64_t kTimeWindowMs = BweReceiver::kPacketLossTimeWindowMs;
+
+  const MediaPacket media_packet1(0, 0, 0, 1);
+  const MediaPacket media_packet2(0, 0, 0, 1000);
+  // Only these two packets will be considered.
+  bwe_receiver_.ReceivePacket(0, media_packet1);
+  bwe_receiver_.ReceivePacket(0, media_packet2);
+  EXPECT_NEAR(bwe_receiver_.RecentPacketLossRatio(), 0.998f, 0.0001f);
+
+  const MediaPacket media_packet3(0, 0, 0, 0);
+  const MediaPacket media_packet4(0, 0, 0, 0x8000);
+  // Only these two packets will be considered.
+  bwe_receiver_.ReceivePacket(2 * kTimeWindowMs, media_packet3);
+  bwe_receiver_.ReceivePacket(2 * kTimeWindowMs, media_packet4);
+  EXPECT_NEAR(bwe_receiver_.RecentPacketLossRatio(), 0.99994f, 0.00001f);
+}
+
+// Packets arriving unordered should not be counted as losted.
+TEST_F(BweReceiverTest, PacketLossUnorderedPackets) {
+  size_t num_packets = bwe_receiver_.GetSetCapacity() / 2;
+  std::vector<uint16_t> sequence_numbers;
+
+  for (size_t i = 0; i < num_packets; ++i) {
+    sequence_numbers.push_back(static_cast<uint16_t>(i + 1));
+  }
+
+  random_shuffle(sequence_numbers.begin(), sequence_numbers.end());
+
+  for (size_t i = 0; i < num_packets; ++i) {
+    const MediaPacket media_packet(kFlowId, 0, 0, sequence_numbers[i]);
+    // Arrival time = 0, all packets will be considered.
+    bwe_receiver_.ReceivePacket(0, media_packet);
+  }
+
+  EXPECT_EQ(bwe_receiver_.RecentPacketLossRatio(), 0.0f);
+}
+
+TEST_F(BweReceiverTest, RecentKbps) {
+  EXPECT_EQ(bwe_receiver_.RecentKbps(), 0U);
+
+  const size_t kPacketSizeBytes = 1200;
+  const int kNumPackets = 100;
+
+  double window_size_s = bwe_receiver_.BitrateWindowS();
+
+  // Receive packets at the same time.
+  for (int i = 0; i < kNumPackets; ++i) {
+    MediaPacket packet(kFlowId, 0L, kPacketSizeBytes, static_cast<uint16_t>(i));
+    bwe_receiver_.ReceivePacket(0, packet);
+  }
+
+  EXPECT_NEAR(bwe_receiver_.RecentKbps(),
+              (8 * kNumPackets * kPacketSizeBytes) / (1000 * window_size_s),
+              10);
+
+  int64_t time_gap_ms =
+      2 * 1000 * window_size_s;  // Larger than rate_counter time window.
+
+  MediaPacket packet(kFlowId, time_gap_ms * 1000, kPacketSizeBytes,
+                     static_cast<uint16_t>(kNumPackets));
+  bwe_receiver_.ReceivePacket(time_gap_ms, packet);
+
+  EXPECT_NEAR(bwe_receiver_.RecentKbps(),
+              (8 * kPacketSizeBytes) / (1000 * window_size_s), 10);
+}
+
+TEST_F(BweReceiverTest, Loss) {
+  EXPECT_NEAR(bwe_receiver_.GlobalReceiverPacketLossRatio(), 0.0f, 0.001f);
+
+  LossAccount loss_account = bwe_receiver_.LinkedSetPacketLossRatio();
+  EXPECT_NEAR(loss_account.LossRatio(), 0.0f, 0.001f);
+
+  // Insert packets 1-50 and 151-200;
+  for (int i = 1; i <= 200; ++i) {
+    // Packet size and timestamp do not matter here.
+    MediaPacket packet(kFlowId, 0L, 0UL, static_cast<uint16_t>(i));
+    bwe_receiver_.ReceivePacket(0, packet);
+    if (i == 50) {
+      i += 100;
+    }
+  }
+
+  loss_account = bwe_receiver_.LinkedSetPacketLossRatio();
+  EXPECT_NEAR(loss_account.LossRatio(), 0.5f, 0.001f);
+
+  bwe_receiver_.RelieveSetAndUpdateLoss();
+  EXPECT_EQ(bwe_receiver_.received_packets_.size(), 100U / 10);
+
+  // No packet loss within the preserved packets.
+  loss_account = bwe_receiver_.LinkedSetPacketLossRatio();
+  EXPECT_NEAR(loss_account.LossRatio(), 0.0f, 0.001f);
+
+  // RelieveSetAndUpdateLoss automatically updates loss account.
+  EXPECT_NEAR(bwe_receiver_.GlobalReceiverPacketLossRatio(), 0.5f, 0.001f);
+}
+
+}  // namespace bwe
+}  // namespace testing
+}  // namespace webrtc