1 files changed, 171 insertions, 0 deletions
diff --git a/third_party/libwebrtc/modules/audio_processing/aec3/render_signal_analyzer_unittest.cc b/third_party/libwebrtc/modules/audio_processing/aec3/render_signal_analyzer_unittest.cc
new file mode 100644
index 0000000000..16f6280cb6
--- /dev/null
+++ b/third_party/libwebrtc/modules/audio_processing/aec3/render_signal_analyzer_unittest.cc
@@ -0,0 +1,171 @@
+/*
+ *  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 "modules/audio_processing/aec3/render_signal_analyzer.h"
+
+#include <math.h>
+
+#include <array>
+#include <cmath>
+#include <vector>
+
+#include "api/array_view.h"
+#include "modules/audio_processing/aec3/aec3_common.h"
+#include "modules/audio_processing/aec3/aec3_fft.h"
+#include "modules/audio_processing/aec3/fft_data.h"
+#include "modules/audio_processing/aec3/render_delay_buffer.h"
+#include "modules/audio_processing/test/echo_canceller_test_tools.h"
+#include "rtc_base/random.h"
+#include "rtc_base/strings/string_builder.h"
+#include "test/gtest.h"
+
+namespace webrtc {
+namespace {
+
+constexpr float kPi = 3.141592f;
+
+void ProduceSinusoidInNoise(int sample_rate_hz,
+                            size_t sinusoid_channel,
+                            float sinusoidal_frequency_hz,
+                            Random* random_generator,
+                            size_t* sample_counter,
+                            Block* x) {
+  // Fill x with low-amplitude noise.
+  for (int band = 0; band < x->NumBands(); ++band) {
+    for (int channel = 0; channel < x->NumChannels(); ++channel) {
+      RandomizeSampleVector(random_generator, x->View(band, channel),
+                            /*amplitude=*/500.f);
+    }
+  }
+  // Produce a sinusoid of the specified frequency in the specified channel.
+  for (size_t k = *sample_counter, j = 0; k < (*sample_counter + kBlockSize);
+       ++k, ++j) {
+    x->View(/*band=*/0, sinusoid_channel)[j] +=
+        32000.f *
+        std::sin(2.f * kPi * sinusoidal_frequency_hz * k / sample_rate_hz);
+  }
+  *sample_counter = *sample_counter + kBlockSize;
+}
+
+void RunNarrowBandDetectionTest(size_t num_channels) {
+  RenderSignalAnalyzer analyzer(EchoCanceller3Config{});
+  Random random_generator(42U);
+  constexpr int kSampleRateHz = 48000;
+  constexpr size_t kNumBands = NumBandsForRate(kSampleRateHz);
+  Block x(kNumBands, num_channels);
+  std::array<float, kBlockSize> x_old;
+  Aec3Fft fft;
+  EchoCanceller3Config config;
+  std::unique_ptr<RenderDelayBuffer> render_delay_buffer(
+      RenderDelayBuffer::Create(config, kSampleRateHz, num_channels));
+
+  std::array<float, kFftLengthBy2Plus1> mask;
+  x_old.fill(0.f);
+  constexpr int kSinusFrequencyBin = 32;
+
+  auto generate_sinusoid_test = [&](bool known_delay) {
+    size_t sample_counter = 0;
+    for (size_t k = 0; k < 100; ++k) {
+      ProduceSinusoidInNoise(16000, num_channels - 1,
+                             16000 / 2 * kSinusFrequencyBin / kFftLengthBy2,
+                             &random_generator, &sample_counter, &x);
+
+      render_delay_buffer->Insert(x);
+      if (k == 0) {
+        render_delay_buffer->Reset();
+      }
+      render_delay_buffer->PrepareCaptureProcessing();
+
+      analyzer.Update(*render_delay_buffer->GetRenderBuffer(),
+                      known_delay ? absl::optional<size_t>(0) : absl::nullopt);
+    }
+  };
+
+  generate_sinusoid_test(true);
+  mask.fill(1.f);
+  analyzer.MaskRegionsAroundNarrowBands(&mask);
+  for (int k = 0; k < static_cast<int>(mask.size()); ++k) {
+    EXPECT_EQ(abs(k - kSinusFrequencyBin) <= 2 ? 0.f : 1.f, mask[k]);
+  }
+  EXPECT_TRUE(analyzer.PoorSignalExcitation());
+  EXPECT_TRUE(static_cast<bool>(analyzer.NarrowPeakBand()));
+  EXPECT_EQ(*analyzer.NarrowPeakBand(), 32);
+
+  // Verify that no bands are detected as narrow when the delay is unknown.
+  generate_sinusoid_test(false);
+  mask.fill(1.f);
+  analyzer.MaskRegionsAroundNarrowBands(&mask);
+  std::for_each(mask.begin(), mask.end(), [](float a) { EXPECT_EQ(1.f, a); });
+  EXPECT_FALSE(analyzer.PoorSignalExcitation());
+}
+
+std::string ProduceDebugText(size_t num_channels) {
+  rtc::StringBuilder ss;
+  ss << "number of channels: " << num_channels;
+  return ss.Release();
+}
+}  // namespace
+
+#if RTC_DCHECK_IS_ON && GTEST_HAS_DEATH_TEST && !defined(WEBRTC_ANDROID)
+// Verifies that the check for non-null output parameter works.
+TEST(RenderSignalAnalyzerDeathTest, NullMaskOutput) {
+  RenderSignalAnalyzer analyzer(EchoCanceller3Config{});
+  EXPECT_DEATH(analyzer.MaskRegionsAroundNarrowBands(nullptr), "");
+}
+
+#endif
+
+// Verify that no narrow bands are detected in a Gaussian noise signal.
+TEST(RenderSignalAnalyzer, NoFalseDetectionOfNarrowBands) {
+  for (auto num_channels : {1, 2, 8}) {
+    SCOPED_TRACE(ProduceDebugText(num_channels));
+    RenderSignalAnalyzer analyzer(EchoCanceller3Config{});
+    Random random_generator(42U);
+    Block x(3, num_channels);
+    std::array<float, kBlockSize> x_old;
+    std::unique_ptr<RenderDelayBuffer> render_delay_buffer(
+        RenderDelayBuffer::Create(EchoCanceller3Config(), 48000, num_channels));
+    std::array<float, kFftLengthBy2Plus1> mask;
+    x_old.fill(0.f);
+
+    for (int k = 0; k < 100; ++k) {
+      for (int band = 0; band < x.NumBands(); ++band) {
+        for (int channel = 0; channel < x.NumChannels(); ++channel) {
+          RandomizeSampleVector(&random_generator, x.View(band, channel));
+        }
+      }
+
+      render_delay_buffer->Insert(x);
+      if (k == 0) {
+        render_delay_buffer->Reset();
+      }
+      render_delay_buffer->PrepareCaptureProcessing();
+
+      analyzer.Update(*render_delay_buffer->GetRenderBuffer(),
+                      absl::optional<size_t>(0));
+    }
+
+    mask.fill(1.f);
+    analyzer.MaskRegionsAroundNarrowBands(&mask);
+    EXPECT_TRUE(std::all_of(mask.begin(), mask.end(),
+                            [](float a) { return a == 1.f; }));
+    EXPECT_FALSE(analyzer.PoorSignalExcitation());
+    EXPECT_FALSE(static_cast<bool>(analyzer.NarrowPeakBand()));
+  }
+}
+
+// Verify that a sinusoid signal is detected as narrow bands.
+TEST(RenderSignalAnalyzer, NarrowBandDetection) {
+  for (auto num_channels : {1, 2, 8}) {
+    SCOPED_TRACE(ProduceDebugText(num_channels));
+    RunNarrowBandDetectionTest(num_channels);
+  }
+}
+}  // namespace webrtc