Finalization of the first version of EchoCanceller 3

webrtc/modules/audio_processing/aec3/comfort_noise_generator_unittest.cc

+/*
+ *  Copyright (c) 2017 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/audio_processing/aec3/comfort_noise_generator.h"
+
+#include <algorithm>
+#include <numeric>
+
+#include "webrtc/test/gtest.h"
+
+namespace webrtc {
+namespace {
+
+float Power(const FftData& N) {
+  std::array<float, kFftLengthBy2Plus1> N2;
+  N.Spectrum(&N2);
+  return std::accumulate(N2.begin(), N2.end(), 0.f) / N2.size();
+}
+
+}  // namespace
+
+#if RTC_DCHECK_IS_ON && GTEST_HAS_DEATH_TEST && !defined(WEBRTC_ANDROID)
+
+TEST(ComfortNoiseGenerator, NullLowerBandNoise) {
+  std::array<float, kFftLengthBy2Plus1> N2;
+  FftData noise;
+  EXPECT_DEATH(ComfortNoiseGenerator().Compute(N2, nullptr, &noise), "");
+}
+
+TEST(ComfortNoiseGenerator, NullUpperBandNoise) {
+  std::array<float, kFftLengthBy2Plus1> N2;
+  FftData noise;
+  EXPECT_DEATH(ComfortNoiseGenerator().Compute(N2, &noise, nullptr), "");
+}
+
+#endif
+
+TEST(ComfortNoiseGenerator, CorrectLevel) {
+  ComfortNoiseGenerator cng;
+
+  std::array<float, kFftLengthBy2Plus1> N2;
+  N2.fill(1000.f * 1000.f);
+
+  FftData n_lower;
+  FftData n_upper;
+  n_lower.re.fill(0.f);
+  n_lower.im.fill(0.f);
+  n_upper.re.fill(0.f);
+  n_upper.im.fill(0.f);
+
+  // Ensure instantaneous updata to nonzero noise.
+  cng.Compute(N2, &n_lower, &n_upper);
+  EXPECT_LT(0.f, Power(n_lower));
+  EXPECT_LT(0.f, Power(n_upper));
+
+  for (int k = 0; k < 10000; ++k) {
+    cng.Compute(N2, &n_lower, &n_upper);
+  }
+  EXPECT_NEAR(N2[0], Power(n_lower), N2[0] / 10.f);
+  EXPECT_NEAR(N2[0], Power(n_upper), N2[0] / 10.f);
+}
+
+}  // namespace webrtc