| /* |
| * Copyright (c) 2016 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/congestion_controller/median_slope_estimator.h" |
| #include "webrtc/rtc_base/random.h" |
| #include "webrtc/test/gtest.h" |
| |
| namespace webrtc { |
| |
| namespace { |
| constexpr size_t kWindowSize = 20; |
| constexpr double kGain = 1; |
| constexpr int64_t kAvgTimeBetweenPackets = 10; |
| constexpr size_t kPacketCount = 2 * kWindowSize + 1; |
| |
| void TestEstimator(double slope, double jitter_stddev, double tolerance) { |
| MedianSlopeEstimator estimator(kWindowSize, kGain); |
| Random random(0x1234567); |
| int64_t send_times[kPacketCount]; |
| int64_t recv_times[kPacketCount]; |
| int64_t send_start_time = random.Rand(1000000); |
| int64_t recv_start_time = random.Rand(1000000); |
| for (size_t i = 0; i < kPacketCount; ++i) { |
| send_times[i] = send_start_time + i * kAvgTimeBetweenPackets; |
| double latency = i * kAvgTimeBetweenPackets / (1 - slope); |
| double jitter = random.Gaussian(0, jitter_stddev); |
| recv_times[i] = recv_start_time + latency + jitter; |
| } |
| for (size_t i = 1; i < kPacketCount; ++i) { |
| double recv_delta = recv_times[i] - recv_times[i - 1]; |
| double send_delta = send_times[i] - send_times[i - 1]; |
| estimator.Update(recv_delta, send_delta, recv_times[i]); |
| if (i < kWindowSize) |
| EXPECT_NEAR(estimator.trendline_slope(), 0, 0.001); |
| else |
| EXPECT_NEAR(estimator.trendline_slope(), slope, tolerance); |
| } |
| } |
| } // namespace |
| |
| TEST(MedianSlopeEstimator, PerfectLineSlopeOneHalf) { |
| TestEstimator(0.5, 0, 0.001); |
| } |
| |
| TEST(MedianSlopeEstimator, PerfectLineSlopeMinusOne) { |
| TestEstimator(-1, 0, 0.001); |
| } |
| |
| TEST(MedianSlopeEstimator, PerfectLineSlopeZero) { |
| TestEstimator(0, 0, 0.001); |
| } |
| |
| TEST(MedianSlopeEstimator, JitteryLineSlopeOneHalf) { |
| TestEstimator(0.5, kAvgTimeBetweenPackets / 3.0, 0.01); |
| } |
| |
| TEST(MedianSlopeEstimator, JitteryLineSlopeMinusOne) { |
| TestEstimator(-1, kAvgTimeBetweenPackets / 3.0, 0.05); |
| } |
| |
| TEST(MedianSlopeEstimator, JitteryLineSlopeZero) { |
| TestEstimator(0, kAvgTimeBetweenPackets / 3.0, 0.02); |
| } |
| |
| } // namespace webrtc |