Implementing auto pausing of video streams.

webrtc/call/bitrate_allocator_unittest.cc

 /*
  *  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 <algorithm>
 #include <memory>
 #include <vector>
 
 #include "testing/gtest/include/gtest/gtest.h"
 #include "webrtc/call/bitrate_allocator.h"
 #include "webrtc/modules/bitrate_controller/include/bitrate_controller.h"
 
 namespace webrtc {
 
 class TestBitrateObserver : public BitrateAllocatorObserver {
  public:
   TestBitrateObserver()
-      : last_bitrate_(0), last_fraction_loss_(0), last_rtt_(0) {}
+      : last_bitrate_bps_(0), last_fraction_loss_(0), last_rtt_ms_(0) {}
 
-  virtual void OnBitrateUpdated(uint32_t bitrate,
-                                uint8_t fraction_loss,
-                                int64_t rtt) {
-    last_bitrate_ = bitrate;
+  void OnBitrateUpdated(uint32_t bitrate_bps,
+                        uint8_t fraction_loss,
+                        int64_t rtt) override {
+    last_bitrate_bps_ = bitrate_bps;
     last_fraction_loss_ = fraction_loss;
-    last_rtt_ = rtt;
+    last_rtt_ms_ = rtt;
   }
-  uint32_t last_bitrate_;
+  uint32_t last_bitrate_bps_;
   uint8_t last_fraction_loss_;
-  int64_t last_rtt_;
+  int64_t last_rtt_ms_;
 };
 
 class BitrateAllocatorTest : public ::testing::Test {
  protected:
   BitrateAllocatorTest() : allocator_(new BitrateAllocator()) {
     allocator_->OnNetworkChanged(300000u, 0, 0);
   }
   ~BitrateAllocatorTest() {}
 
   std::unique_ptr<BitrateAllocator> allocator_;
 };
 
 TEST_F(BitrateAllocatorTest, UpdatingBitrateObserver) {
   TestBitrateObserver bitrate_observer;
   int start_bitrate =
       allocator_->AddObserver(&bitrate_observer, 100000, 1500000, true);
   EXPECT_EQ(300000, start_bitrate);
   allocator_->OnNetworkChanged(200000, 0, 0);
-  EXPECT_EQ(200000u, bitrate_observer.last_bitrate_);
+  EXPECT_EQ(200000u, bitrate_observer.last_bitrate_bps_);
 
   // TODO(pbos): Expect capping to 1.5M instead of 3M when not boosting the max
   // bitrate for FEC/retransmissions (see todo in BitrateAllocator).
   allocator_->OnNetworkChanged(4000000, 0, 0);
-  EXPECT_EQ(3000000u, bitrate_observer.last_bitrate_);
+  EXPECT_EQ(3000000u, bitrate_observer.last_bitrate_bps_);
   start_bitrate =
       allocator_->AddObserver(&bitrate_observer, 100000, 4000000, true);
   EXPECT_EQ(4000000, start_bitrate);
 
   start_bitrate =
       allocator_->AddObserver(&bitrate_observer, 100000, 1500000, true);
   EXPECT_EQ(3000000, start_bitrate);
-  EXPECT_EQ(3000000u, bitrate_observer.last_bitrate_);
+  EXPECT_EQ(3000000u, bitrate_observer.last_bitrate_bps_);
   allocator_->OnNetworkChanged(1500000, 0, 0);
-  EXPECT_EQ(1500000u, bitrate_observer.last_bitrate_);
+  EXPECT_EQ(1500000u, bitrate_observer.last_bitrate_bps_);
 }
 
 TEST_F(BitrateAllocatorTest, TwoBitrateObserversOneRtcpObserver) {
   TestBitrateObserver bitrate_observer_1;
   TestBitrateObserver bitrate_observer_2;
   int start_bitrate =
       allocator_->AddObserver(&bitrate_observer_1, 100000, 300000, true);
   EXPECT_EQ(300000, start_bitrate);
   start_bitrate =
       allocator_->AddObserver(&bitrate_observer_2, 200000, 300000, true);
   EXPECT_EQ(200000, start_bitrate);
 
   // Test too low start bitrate, hence lower than sum of min. Min bitrates will
   // be allocated to all observers.
   allocator_->OnNetworkChanged(200000, 0, 50);
-  EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_);
+  EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_bps_);
   EXPECT_EQ(0, bitrate_observer_1.last_fraction_loss_);
-  EXPECT_EQ(50, bitrate_observer_1.last_rtt_);
-  EXPECT_EQ(200000u, bitrate_observer_2.last_bitrate_);
+  EXPECT_EQ(50, bitrate_observer_1.last_rtt_ms_);
+  EXPECT_EQ(200000u, bitrate_observer_2.last_bitrate_bps_);
   EXPECT_EQ(0, bitrate_observer_2.last_fraction_loss_);
-  EXPECT_EQ(50, bitrate_observer_2.last_rtt_);
+  EXPECT_EQ(50, bitrate_observer_2.last_rtt_ms_);
 
   // Test a bitrate which should be distributed equally.
   allocator_->OnNetworkChanged(500000, 0, 50);
   const uint32_t kBitrateToShare = 500000 - 200000 - 100000;
-  EXPECT_EQ(100000u + kBitrateToShare / 2, bitrate_observer_1.last_bitrate_);
-  EXPECT_EQ(200000u + kBitrateToShare / 2, bitrate_observer_2.last_bitrate_);
+  EXPECT_EQ(100000u + kBitrateToShare / 2,
+            bitrate_observer_1.last_bitrate_bps_);
+  EXPECT_EQ(200000u + kBitrateToShare / 2,
+            bitrate_observer_2.last_bitrate_bps_);
 
   // Limited by 2x max bitrates since we leave room for FEC and retransmissions.
   allocator_->OnNetworkChanged(1500000, 0, 50);
-  EXPECT_EQ(600000u, bitrate_observer_1.last_bitrate_);
-  EXPECT_EQ(600000u, bitrate_observer_2.last_bitrate_);
+  EXPECT_EQ(600000u, bitrate_observer_1.last_bitrate_bps_);
+  EXPECT_EQ(600000u, bitrate_observer_2.last_bitrate_bps_);
 
   // Verify that if the bandwidth estimate is set to zero, the allocated rate is
   // zero.
   allocator_->OnNetworkChanged(0, 0, 50);
-  EXPECT_EQ(0u, bitrate_observer_1.last_bitrate_);
-  EXPECT_EQ(0u, bitrate_observer_2.last_bitrate_);
+  EXPECT_EQ(0u, bitrate_observer_1.last_bitrate_bps_);
+  EXPECT_EQ(0u, bitrate_observer_2.last_bitrate_bps_);
 }
 
 class BitrateAllocatorTestNoEnforceMin : public ::testing::Test {
  protected:
   BitrateAllocatorTestNoEnforceMin() : allocator_(new BitrateAllocator()) {
     allocator_->OnNetworkChanged(300000u, 0, 0);
   }
   ~BitrateAllocatorTestNoEnforceMin() {}
 
   std::unique_ptr<BitrateAllocator> allocator_;
 };
 
-// The following three tests verify that the EnforceMinBitrate() method works
-// as intended.
+// The following three tests verify enforcing a minimum bitrate works as
+// intended.
 TEST_F(BitrateAllocatorTestNoEnforceMin, OneBitrateObserver) {
   TestBitrateObserver bitrate_observer_1;
   int start_bitrate =
       allocator_->AddObserver(&bitrate_observer_1, 100000, 400000, false);
   EXPECT_EQ(300000, start_bitrate);
 
-  // High REMB.
+  // High BWE.
   allocator_->OnNetworkChanged(150000, 0, 0);
-  EXPECT_EQ(150000u, bitrate_observer_1.last_bitrate_);
+  EXPECT_EQ(150000u, bitrate_observer_1.last_bitrate_bps_);
 
-  // Low REMB.
+  // Low BWE.
   allocator_->OnNetworkChanged(10000, 0, 0);
-  EXPECT_EQ(10000u, bitrate_observer_1.last_bitrate_);
+  EXPECT_EQ(0u, bitrate_observer_1.last_bitrate_bps_);
 
   allocator_->RemoveObserver(&bitrate_observer_1);
 }
 
 TEST_F(BitrateAllocatorTestNoEnforceMin, ThreeBitrateObservers) {
   TestBitrateObserver bitrate_observer_1;
   TestBitrateObserver bitrate_observer_2;
   TestBitrateObserver bitrate_observer_3;
   // Set up the observers with min bitrates at 100000, 200000, and 300000.
   int start_bitrate =
       allocator_->AddObserver(&bitrate_observer_1, 100000, 400000, false);
   EXPECT_EQ(300000, start_bitrate);
 
   start_bitrate =
       allocator_->AddObserver(&bitrate_observer_2, 200000, 400000, false);
   EXPECT_EQ(200000, start_bitrate);
-  EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_);
+  EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_bps_);
 
   start_bitrate =
       allocator_->AddObserver(&bitrate_observer_3, 300000, 400000, false);
   EXPECT_EQ(0, start_bitrate);
-  EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_);
-  EXPECT_EQ(200000u, bitrate_observer_2.last_bitrate_);
+  EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_bps_);
+  EXPECT_EQ(200000u, bitrate_observer_2.last_bitrate_bps_);
 
-  // High REMB. Make sure the controllers get a fair share of the surplus
-  // (i.e., what is left after each controller gets its min rate).
+  // High BWE. Make sure the controllers get a fair share of the surplus (i.e.,
+  // what is left after each controller gets its min rate).
   allocator_->OnNetworkChanged(690000, 0, 0);
   // Verify that each observer gets its min rate (sum of min rates is 600000),
   // and that the remaining 90000 is divided equally among the three.
   uint32_t bitrate_to_share = 690000u - 100000u - 200000u - 300000u;
-  EXPECT_EQ(100000u + bitrate_to_share / 3, bitrate_observer_1.last_bitrate_);
-  EXPECT_EQ(200000u + bitrate_to_share / 3, bitrate_observer_2.last_bitrate_);
-  EXPECT_EQ(300000u + bitrate_to_share / 3, bitrate_observer_3.last_bitrate_);
+  EXPECT_EQ(100000u + bitrate_to_share / 3,
+            bitrate_observer_1.last_bitrate_bps_);
+  EXPECT_EQ(200000u + bitrate_to_share / 3,
+            bitrate_observer_2.last_bitrate_bps_);
+  EXPECT_EQ(300000u + bitrate_to_share / 3,
+            bitrate_observer_3.last_bitrate_bps_);
 
-  // High REMB, but below the sum of min bitrates.
+  // BWE below the sum of observer's min bitrate.
+  allocator_->OnNetworkChanged(300000, 0, 0);
+  EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_bps_);  // Min bitrate.
+  EXPECT_EQ(200000u, bitrate_observer_2.last_bitrate_bps_);  // Min bitrate.
+  EXPECT_EQ(0u, bitrate_observer_3.last_bitrate_bps_);  // Nothing.
+
+  // Increased BWE, but still below the sum of configured min bitrates for all
+  // observers and too little for observer 3. 1 and 2 will share the rest.
   allocator_->OnNetworkChanged(500000, 0, 0);
-  // Verify that the first and second observers get their min bitrates, and the
-  // third gets the remainder.
-  EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_);  // Min bitrate.
-  EXPECT_EQ(200000u, bitrate_observer_2.last_bitrate_);  // Min bitrate.
-  EXPECT_EQ(200000u, bitrate_observer_3.last_bitrate_);  // Remainder.
+  EXPECT_EQ(200000u, bitrate_observer_1.last_bitrate_bps_);  // Min + split.
+  EXPECT_EQ(300000u, bitrate_observer_2.last_bitrate_bps_);  // Min + split.
+  EXPECT_EQ(0u, bitrate_observer_3.last_bitrate_bps_);  // Nothing.
 
-  // Low REMB.
+  // Below min for all.
   allocator_->OnNetworkChanged(10000, 0, 0);
-  // Verify that the first observer gets all the rate, and the rest get zero.
-  EXPECT_EQ(10000u, bitrate_observer_1.last_bitrate_);
-  EXPECT_EQ(0u, bitrate_observer_2.last_bitrate_);
-  EXPECT_EQ(0u, bitrate_observer_3.last_bitrate_);
+  EXPECT_EQ(0u, bitrate_observer_1.last_bitrate_bps_);
+  EXPECT_EQ(0u, bitrate_observer_2.last_bitrate_bps_);
+  EXPECT_EQ(0u, bitrate_observer_3.last_bitrate_bps_);
 
-  allocator_->OnNetworkChanged(0, 0, 0);
   // Verify that zero estimated bandwidth, means that that all gets zero,
   // regardless of set min bitrate.
-  EXPECT_EQ(0u, bitrate_observer_1.last_bitrate_);
-  EXPECT_EQ(0u, bitrate_observer_2.last_bitrate_);
-  EXPECT_EQ(0u, bitrate_observer_3.last_bitrate_);
+  allocator_->OnNetworkChanged(0, 0, 0);
+  EXPECT_EQ(0u, bitrate_observer_1.last_bitrate_bps_);
+  EXPECT_EQ(0u, bitrate_observer_2.last_bitrate_bps_);
+  EXPECT_EQ(0u, bitrate_observer_3.last_bitrate_bps_);
 
   allocator_->RemoveObserver(&bitrate_observer_1);
   allocator_->RemoveObserver(&bitrate_observer_2);
   allocator_->RemoveObserver(&bitrate_observer_3);
 }
 
-TEST_F(BitrateAllocatorTest, ThreeBitrateObserversLowRembEnforceMin) {
+TEST_F(BitrateAllocatorTest, ThreeBitrateObserversLowBweEnforceMin) {
   TestBitrateObserver bitrate_observer_1;
   TestBitrateObserver bitrate_observer_2;
   TestBitrateObserver bitrate_observer_3;
   int start_bitrate =
       allocator_->AddObserver(&bitrate_observer_1, 100000, 400000, true);
   EXPECT_EQ(300000, start_bitrate);
 
   start_bitrate =
       allocator_->AddObserver(&bitrate_observer_2, 200000, 400000, true);
   EXPECT_EQ(200000, start_bitrate);
-  EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_);
+  EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_bps_);
 
   start_bitrate =
       allocator_->AddObserver(&bitrate_observer_3, 300000, 400000, true);
   EXPECT_EQ(300000, start_bitrate);
-  EXPECT_EQ(100000, static_cast<int>(bitrate_observer_1.last_bitrate_));
-  EXPECT_EQ(200000, static_cast<int>(bitrate_observer_2.last_bitrate_));
+  EXPECT_EQ(100000, static_cast<int>(bitrate_observer_1.last_bitrate_bps_));
+  EXPECT_EQ(200000, static_cast<int>(bitrate_observer_2.last_bitrate_bps_));
 
-  // Low REMB. Verify that all observers still get their respective min bitrate.
+  // Low BWE. Verify that all observers still get their respective min bitrate.
   allocator_->OnNetworkChanged(1000, 0, 0);
-  EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_);  // Min cap.
-  EXPECT_EQ(200000u, bitrate_observer_2.last_bitrate_);  // Min cap.
-  EXPECT_EQ(300000u, bitrate_observer_3.last_bitrate_);  // Min cap.
+  EXPECT_EQ(100000u, bitrate_observer_1.last_bitrate_bps_);  // Min cap.
+  EXPECT_EQ(200000u, bitrate_observer_2.last_bitrate_bps_);  // Min cap.
+  EXPECT_EQ(300000u, bitrate_observer_3.last_bitrate_bps_);  // Min cap.
 
   allocator_->RemoveObserver(&bitrate_observer_1);
   allocator_->RemoveObserver(&bitrate_observer_2);
   allocator_->RemoveObserver(&bitrate_observer_3);
 }
 
 TEST_F(BitrateAllocatorTest, AddObserverWhileNetworkDown) {
   TestBitrateObserver bitrate_observer_1;
   int start_bitrate =
       allocator_->AddObserver(&bitrate_observer_1, 50000, 400000, true);
   EXPECT_EQ(300000, start_bitrate);
 
   // Set network down, ie, no available bitrate.
   allocator_->OnNetworkChanged(0, 0, 0);
 
-  EXPECT_EQ(0u, bitrate_observer_1.last_bitrate_);
+  EXPECT_EQ(0u, bitrate_observer_1.last_bitrate_bps_);
 
   TestBitrateObserver bitrate_observer_2;
   start_bitrate =
       allocator_->AddObserver(&bitrate_observer_2, 50000, 400000, true);
 
   // Expect the start_bitrate to be set as if the network was still up but that
   // the new observer have been notified that the network is down.
   EXPECT_EQ(300000 / 2, start_bitrate);
-  EXPECT_EQ(0u, bitrate_observer_1.last_bitrate_);
-  EXPECT_EQ(0u, bitrate_observer_2.last_bitrate_);
+  EXPECT_EQ(0u, bitrate_observer_1.last_bitrate_bps_);
+  EXPECT_EQ(0u, bitrate_observer_2.last_bitrate_bps_);
 
   // Set network back up.
   allocator_->OnNetworkChanged(1500000, 0, 50);
-  EXPECT_EQ(750000u, bitrate_observer_1.last_bitrate_);
-  EXPECT_EQ(750000u, bitrate_observer_2.last_bitrate_);
+  EXPECT_EQ(750000u, bitrate_observer_1.last_bitrate_bps_);
+  EXPECT_EQ(750000u, bitrate_observer_2.last_bitrate_bps_);
+}
+
+TEST_F(BitrateAllocatorTest, MixedEnforecedConfigs) {
+  TestBitrateObserver enforced_observer;
+  int start_bitrate =
+      allocator_->AddObserver(&enforced_observer, 6000, 30000, true);
+  EXPECT_EQ(60000, start_bitrate);
+
+  TestBitrateObserver not_enforced_observer;
+  start_bitrate =
+      allocator_->AddObserver(&not_enforced_observer, 30000, 2500000, false);
+  EXPECT_EQ(270000, start_bitrate);
+  EXPECT_EQ(30000u, enforced_observer.last_bitrate_bps_);
+
+  allocator_->OnNetworkChanged(36000, 0, 50);
+  EXPECT_EQ(6000u, enforced_observer.last_bitrate_bps_);
+  EXPECT_EQ(30000u, not_enforced_observer.last_bitrate_bps_);
+
+  allocator_->OnNetworkChanged(35000, 0, 50);
+  EXPECT_EQ(30000u, enforced_observer.last_bitrate_bps_);
+  EXPECT_EQ(0u, not_enforced_observer.last_bitrate_bps_);
+
+  allocator_->OnNetworkChanged(5000, 0, 50);
+  EXPECT_EQ(6000u, enforced_observer.last_bitrate_bps_);
+  EXPECT_EQ(0u, not_enforced_observer.last_bitrate_bps_);
+
+  allocator_->OnNetworkChanged(36000, 0, 50);
+  EXPECT_EQ(30000u, enforced_observer.last_bitrate_bps_);
+  EXPECT_EQ(0u, not_enforced_observer.last_bitrate_bps_);
+
+  allocator_->OnNetworkChanged(55000, 0, 50);
+  EXPECT_EQ(30000u, enforced_observer.last_bitrate_bps_);
+  EXPECT_EQ(0u, not_enforced_observer.last_bitrate_bps_);
+
+  allocator_->OnNetworkChanged(56000, 0, 50);
+  EXPECT_EQ(6000u, enforced_observer.last_bitrate_bps_);
+  EXPECT_EQ(50000u, not_enforced_observer.last_bitrate_bps_);
+
+  allocator_->OnNetworkChanged(56000, 0, 50);
+  EXPECT_EQ(16000u, enforced_observer.last_bitrate_bps_);
+  EXPECT_EQ(40000u, not_enforced_observer.last_bitrate_bps_);
+
+  allocator_->RemoveObserver(&enforced_observer);
+  allocator_->RemoveObserver(&not_enforced_observer);
+}
+
+TEST_F(BitrateAllocatorTest, AvoidToggleAbsolute) {
+  TestBitrateObserver observer;
+  int start_bitrate =
+      allocator_->AddObserver(&observer, 30000, 300000, false);
+  EXPECT_EQ(300000, start_bitrate);
+
+  allocator_->OnNetworkChanged(30000, 0, 50);
+  EXPECT_EQ(30000u, observer.last_bitrate_bps_);
+
+  allocator_->OnNetworkChanged(20000, 0, 50);
+  EXPECT_EQ(0u, observer.last_bitrate_bps_);
+
+  allocator_->OnNetworkChanged(30000, 0, 50);
+  EXPECT_EQ(0u, observer.last_bitrate_bps_);
+
+  allocator_->OnNetworkChanged(49000, 0, 50);
+  EXPECT_EQ(0u, observer.last_bitrate_bps_);
+
+  allocator_->OnNetworkChanged(50000, 0, 50);
+  EXPECT_EQ(50000u, observer.last_bitrate_bps_);
+
+  allocator_->OnNetworkChanged(30000, 0, 50);
+  EXPECT_EQ(30000u, observer.last_bitrate_bps_);
+
+  allocator_->RemoveObserver(&observer);
+}
+
+TEST_F(BitrateAllocatorTest, AvoidTogglePercent) {
+  TestBitrateObserver observer;
+  int start_bitrate =
+      allocator_->AddObserver(&observer, 300000, 600000, false);
+  EXPECT_EQ(300000, start_bitrate);
+
+  allocator_->OnNetworkChanged(300000, 0, 50);
+  EXPECT_EQ(300000u, observer.last_bitrate_bps_);
+
+  allocator_->OnNetworkChanged(200000, 0, 50);
+  EXPECT_EQ(0u, observer.last_bitrate_bps_);
+
+  allocator_->OnNetworkChanged(300000, 0, 50);
+  EXPECT_EQ(0u, observer.last_bitrate_bps_);
+
+  allocator_->OnNetworkChanged(329000, 0, 50);
+  EXPECT_EQ(0u, observer.last_bitrate_bps_);
+
+  allocator_->OnNetworkChanged(330000, 0, 50);
+  EXPECT_EQ(330000u, observer.last_bitrate_bps_);
+
+  allocator_->OnNetworkChanged(300000, 0, 50);
+  EXPECT_EQ(300000u, observer.last_bitrate_bps_);
+
+  allocator_->RemoveObserver(&observer);
 }
 
 }  // namespace webrtc