Upgrade AudioRendererAlgorithm to use WSOLA,

media/filters/audio_renderer_algorithm_unittest.cc

Index: media/filters/audio_renderer_algorithm_unittest.cc
diff --git a/media/filters/audio_renderer_algorithm_unittest.cc b/media/filters/audio_renderer_algorithm_unittest.cc
index d5119c00c2b116022f095c868bd059b7f5d67a5b..5cd3eeb01ec7e56efb6f127954e259312dbb05f3 100644
--- a/media/filters/audio_renderer_algorithm_unittest.cc
+++ b/media/filters/audio_renderer_algorithm_unittest.cc
@@ -12,19 +12,49 @@
 
 #include "base/bind.h"
 #include "base/callback.h"
+#include "base/memory/scoped_ptr.h"
 #include "media/base/audio_buffer.h"
 #include "media/base/audio_bus.h"
 #include "media/base/buffers.h"
 #include "media/base/channel_layout.h"
 #include "media/base/test_helpers.h"
 #include "media/filters/audio_renderer_algorithm.h"
+#include "media/filters/audio_renderer_algorithm_util.h"
 #include "testing/gtest/include/gtest/gtest.h"
-
 namespace media {
 
 static const int kFrameSize = 250;
 static const int kSamplesPerSecond = 3000;
 static const SampleFormat kSampleFormat = kSampleFormatS16;
+static const int kOutputDurationInSec = 10;
+
+static void FillWithSquarePuleTrain(

[ajm, 2013/07/23 18:03:28]

Pule -> Pulse

[turaj, 2013/07/29 22:09:57]

Done.

+    int pulse_width, int offset, int channel, AudioBus* audio_bus) {
+  float* ch = audio_bus->channel(channel);
+
+  // Fill backward from |offset| - 1 toward zero, starting with -1, alternating
+  // between -1 and 1 every |pulse_width| samples.
+  int pulse = -1;
+  for (int n = offset - 1, k = 0; n >= 0; --n, ++k) {
+    if (k >= pulse_width) {
+      pulse = -pulse;
+      k = 0;
+    }
+    ch[n] = pulse;
+  }
+
+  // Fill forward from |offset| towards the end, starting with 1, alternating
+  // between 1 and -1 every |pulse_width| samples.
+  pulse = 1;
+  for (int n = offset, k = 0; n < audio_bus->frames(); ++n, ++k) {
+    if (k >= pulse_width) {
+      pulse = -pulse;
+      k = 0;
+    }
+    ch[n] = pulse;
+  }
+}
+
 
 class AudioRendererAlgorithmTest : public testing::Test {
  public:
@@ -118,7 +148,8 @@ class AudioRendererAlgorithmTest : public testing::Test {
 
   void TestPlaybackRate(double playback_rate) {
     const int kDefaultBufferSize = algorithm_.samples_per_second() / 100;
-    const int kDefaultFramesRequested = 2 * algorithm_.samples_per_second();
+    const int kDefaultFramesRequested = kOutputDurationInSec *
+        algorithm_.samples_per_second();
 
     TestPlaybackRate(
         playback_rate, kDefaultBufferSize, kDefaultFramesRequested);
@@ -270,7 +301,7 @@ TEST_F(AudioRendererAlgorithmTest, FillBuffer_JumpAroundSpeeds) {
 TEST_F(AudioRendererAlgorithmTest, FillBuffer_SmallBufferSize) {
   Initialize();
   static const int kBufferSizeInFrames = 1;
-  static const int kFramesRequested = 2 * kSamplesPerSecond;
+  static const int kFramesRequested = kOutputDurationInSec * kSamplesPerSecond;
   TestPlaybackRate(1.0, kBufferSizeInFrames, kFramesRequested);
   TestPlaybackRate(0.5, kBufferSizeInFrames, kFramesRequested);
   TestPlaybackRate(1.5, kBufferSizeInFrames, kFramesRequested);
@@ -297,4 +328,174 @@ TEST_F(AudioRendererAlgorithmTest, FillBuffer_HigherQualityAudio) {
   TestPlaybackRate(1.5);
 }
 
+TEST_F(AudioRendererAlgorithmTest, DotProduct) {
+  const int kChannels = 3;
+  const int kFrames = 20;
+  const int kPulseWidth = 2;
+
+  scoped_ptr<AudioBus> a = AudioBus::Create(kChannels, kFrames);
+  scoped_ptr<AudioBus> b = AudioBus::Create(kChannels, kFrames);
+
+  scoped_ptr<float[]> dot_prod(new float[kChannels]);
+
+  FillWithSquarePuleTrain(kPulseWidth, 0, 0, a.get());
+  FillWithSquarePuleTrain(kPulseWidth, 1, 1, a.get());
+  FillWithSquarePuleTrain(kPulseWidth, 2, 2, a.get());
+
+  FillWithSquarePuleTrain(kPulseWidth, 0, 0, b.get());
+  FillWithSquarePuleTrain(kPulseWidth, 0, 1, b.get());
+  FillWithSquarePuleTrain(kPulseWidth, 0, 2, b.get());
+
+  MultiChannelDotProduct(a.get(), 0, b.get(), 0, kFrames, dot_prod.get());
+
+  EXPECT_FLOAT_EQ(kFrames, dot_prod[0]);
+  EXPECT_FLOAT_EQ(0, dot_prod[1]);
+  EXPECT_FLOAT_EQ(-kFrames, dot_prod[2]);
+
+  MultiChannelDotProduct(a.get(), 4, b.get(), 8, kFrames / 2, dot_prod.get());
+
+  EXPECT_FLOAT_EQ(kFrames / 2, dot_prod[0]);
+  EXPECT_FLOAT_EQ(0, dot_prod[1]);
+  EXPECT_FLOAT_EQ(-kFrames / 2, dot_prod[2]);
+}
+
+TEST_F(AudioRendererAlgorithmTest, MovingWindowEnergy) {
+  const int kChannels = 2;
+  const int kFrames = 20;
+  const int kFramesPerBlock = 3;
+  const int kNumBlocks = kFrames - (kFramesPerBlock - 1);
+  scoped_ptr<AudioBus> a = AudioBus::Create(kChannels, kFrames);
+  scoped_ptr<float[]> energies(new float[kChannels * kNumBlocks]);
+  float* ch_left = a->channel(0);
+  float* ch_right = a->channel(1);
+
+  // Fill up both channels.
+  for (int n = 0; n < kFrames; ++n) {
+    ch_left[n] = n;
+    ch_right[n] = kFrames - 1 - n;
+  }
+
+  MultiChannelMovingWindowEnergies(a.get(), kFramesPerBlock, energies.get());
+
+  for (int n = 0; n < kNumBlocks; ++n) {
+    float expected_energy = 0;
+    for (int k = 0; k < kFramesPerBlock; ++k)
+      expected_energy += ch_left[n + k] * ch_left[n + k];
+    EXPECT_FLOAT_EQ(expected_energy, energies[2 * n]);
+
+    expected_energy = 0;
+    for (int k = 0; k < kFramesPerBlock; ++k)
+      expected_energy += ch_right[n + k] * ch_right[n + k];
+    EXPECT_FLOAT_EQ(expected_energy, energies[2 * n + 1]);
+  }
+}
+
+TEST_F(AudioRendererAlgorithmTest, PartialAndDecimatedSearch) {
+  const int kFramesInSearchRegion = 12;
+  const int kChannels = 2;
+  float ch_0[] = {0.0, 0.0, 0.0, 0.0, 0.0, 1.0, 1.0, 1.0, 0.0, 0.0, 0.0, 0.0};
+  float ch_1[] = {0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.1, 1.0, 0.1, 0.0, 0.0};
+  ASSERT_EQ(sizeof(ch_0), sizeof(ch_1));
+  ASSERT_EQ(static_cast<size_t>(kFramesInSearchRegion),
+            sizeof(ch_0) / sizeof(*ch_0));
+  scoped_ptr<AudioBus> search_region = AudioBus::CreateWrapper(kChannels);
+
+  search_region->SetChannelData(0, ch_0);
+  search_region->SetChannelData(1, ch_1);
+  search_region->set_frames(kFramesInSearchRegion);
+  ASSERT_EQ(kFramesInSearchRegion, search_region->frames());
+
+  const int kFramePerBlock = 4;
+  float target_0[] = {1.0, 1.0, 1.0, 0.0};
+  float target_1[] = {0.0, 1.0, 0.1, 1.0};
+  ASSERT_EQ(sizeof(target_0), sizeof(target_1));
+  ASSERT_EQ(static_cast<size_t>(kFramePerBlock),
+            sizeof(target_0) / sizeof(*target_0));
+
+  scoped_ptr<AudioBus> target = AudioBus::CreateWrapper(2);
+  target->SetChannelData(0, target_0);
+  target->SetChannelData(1, target_1);
+  target->set_frames(kFramePerBlock);
+  ASSERT_EQ(kFramePerBlock, target->frames());
+
+  scoped_ptr<float[]> energy_target(new float[kChannels]);
+
+  MultiChannelDotProduct(target.get(), 0, target.get(), 0, kFramePerBlock,
+                         energy_target.get());
+
+  ASSERT_EQ(3.f, energy_target[0]);
+  ASSERT_EQ(2.01f, energy_target[1]);
+
+  const int kNumCandidBlocks = kFramesInSearchRegion - (kFramePerBlock - 1);
+  scoped_ptr<float[]> energy_candid_blocks(new float[kNumCandidBlocks *
+                                                     kChannels]);
+
+  MultiChannelMovingWindowEnergies(search_region.get(), kFramePerBlock,
+                                   energy_candid_blocks.get());
+
+  ASSERT_FLOAT_EQ(0, energy_candid_blocks[0]);
+  ASSERT_FLOAT_EQ(0, energy_candid_blocks[2]);
+  ASSERT_FLOAT_EQ(1, energy_candid_blocks[4]);
+  ASSERT_FLOAT_EQ(2, energy_candid_blocks[6]);
+  ASSERT_FLOAT_EQ(3, energy_candid_blocks[8]);
+  ASSERT_FLOAT_EQ(3, energy_candid_blocks[10]);
+  ASSERT_FLOAT_EQ(2, energy_candid_blocks[12]);
+  ASSERT_FLOAT_EQ(1, energy_candid_blocks[14]);
+  ASSERT_FLOAT_EQ(0, energy_candid_blocks[16]);
+
+  ASSERT_FLOAT_EQ(0, energy_candid_blocks[1]);
+  ASSERT_FLOAT_EQ(0, energy_candid_blocks[3]);
+  ASSERT_FLOAT_EQ(0, energy_candid_blocks[5]);
+  ASSERT_FLOAT_EQ(0, energy_candid_blocks[7]);
+  ASSERT_FLOAT_EQ(0.01, energy_candid_blocks[9]);
+  ASSERT_FLOAT_EQ(1.01, energy_candid_blocks[11]);
+  ASSERT_FLOAT_EQ(1.02, energy_candid_blocks[13]);
+  ASSERT_FLOAT_EQ(1.02, energy_candid_blocks[15]);
+  ASSERT_FLOAT_EQ(1.01, energy_candid_blocks[17]);
+
+  // An interval which is of no effect.
+  interval exclude_interval = std::make_pair(-100, -10);
+  EXPECT_EQ(5, PartialSearch(0, kNumCandidBlocks - 1, exclude_interval,
+                             target.get(), search_region.get(),
+                             energy_target.get(), energy_candid_blocks.get()));
+
+  // Exclude the the best match.
+  exclude_interval = std::make_pair(2, 5);
+  EXPECT_EQ(7, PartialSearch(0, kNumCandidBlocks - 1, exclude_interval,
+                             target.get(), search_region.get(),
+                             energy_target.get(), energy_candid_blocks.get()));
+
+  // An interval which is of no effect.
+  exclude_interval = std::make_pair(-100, -10);
+  EXPECT_EQ(4, DecimatedSearch(4, exclude_interval, target.get(),
+                               search_region.get(), energy_target.get(),
+                               energy_candid_blocks.get()));
+
+  EXPECT_EQ(5, OptimalIndex(search_region.get(), target.get(),
+                            exclude_interval));
+}
+
+TEST_F(AudioRendererAlgorithmTest, CubicInterpolation) {
+  // Arbitrary coefficients.
+  const float kA = 0.7;
+  const float kB = 1.2;
+  const float kC = 0.8;
+
+  float y_values[3];
+  y_values[0] = kA - kB + kC;
+  y_values[1] = kC;
+  y_values[2] = kA + kB + kC;
+
+  float extremum;
+  float extremum_value;
+
+  CubicInterpol(y_values, &extremum, &extremum_value);
+
+  float x_star = -kB / (2.f * kA);
+  float y_star = kA * x_star * x_star + kB * x_star + kC;
+
+  EXPECT_FLOAT_EQ(x_star, extremum);
+  EXPECT_FLOAT_EQ(y_star, extremum_value);
+}
+
 }  // namespace media