// Copyright 2013 The Chromium Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #include #include "media/base/audio_bus.h" #include "media/base/audio_hash.h" #include "media/base/fake_audio_render_callback.h" #include "testing/gtest/include/gtest/gtest.h" namespace media { static const int kChannelCount = 2; static const int kFrameCount = 1024; static const int kSampleRate = 48000; class AudioHashTest : public testing::Test { public: AudioHashTest() : bus_one_(AudioBus::Create(kChannelCount, kFrameCount)), bus_two_(AudioBus::Create(kChannelCount, kFrameCount)), fake_callback_(0.01, kSampleRate) { // Fill each channel in each bus with unique data. GenerateUniqueChannels(bus_one_.get()); GenerateUniqueChannels(bus_two_.get()); } void GenerateUniqueChannels(AudioBus* audio_bus) { // Use an AudioBus wrapper to avoid an extra memcpy when filling channels. std::unique_ptr wrapped_bus = AudioBus::CreateWrapper(1); wrapped_bus->set_frames(audio_bus->frames()); // Since FakeAudioRenderCallback generates only a single channel of unique // audio data, we need to fill each channel manually. for (int ch = 0; ch < audio_bus->channels(); ++ch) { wrapped_bus->SetChannelData(0, audio_bus->channel(ch)); fake_callback_.Render(base::TimeDelta(), base::TimeTicks::Now(), 0, wrapped_bus.get()); } } AudioHashTest(const AudioHashTest&) = delete; AudioHashTest& operator=(const AudioHashTest&) = delete; ~AudioHashTest() override = default; protected: std::unique_ptr bus_one_; std::unique_ptr bus_two_; FakeAudioRenderCallback fake_callback_; }; // Ensure the same data hashes the same. TEST_F(AudioHashTest, Equivalence) { AudioHash hash_one; hash_one.Update(bus_one_.get(), bus_one_->frames()); AudioHash hash_two; hash_two.Update(bus_one_.get(), bus_one_->frames()); EXPECT_EQ(hash_one.ToString(), hash_two.ToString()); } // Ensure sample order matters to the hash. TEST_F(AudioHashTest, SampleOrder) { AudioHash original_hash; original_hash.Update(bus_one_.get(), bus_one_->frames()); // Swap a sample in the bus. std::swap(bus_one_->channel(0)[0], bus_one_->channel(0)[1]); AudioHash swapped_hash; swapped_hash.Update(bus_one_.get(), bus_one_->frames()); EXPECT_NE(original_hash.ToString(), swapped_hash.ToString()); } // Ensure channel order matters to the hash. TEST_F(AudioHashTest, ChannelOrder) { AudioHash original_hash; original_hash.Update(bus_one_.get(), bus_one_->frames()); // Reverse channel order for the same sample data. const int channels = bus_one_->channels(); std::unique_ptr swapped_ch_bus = AudioBus::CreateWrapper(channels); swapped_ch_bus->set_frames(bus_one_->frames()); for (int i = channels - 1; i >= 0; --i) swapped_ch_bus->SetChannelData(channels - (i + 1), bus_one_->channel(i)); AudioHash swapped_hash; swapped_hash.Update(swapped_ch_bus.get(), swapped_ch_bus->frames()); EXPECT_NE(original_hash.ToString(), swapped_hash.ToString()); } // Ensure bus order matters to the hash. TEST_F(AudioHashTest, BusOrder) { AudioHash original_hash; original_hash.Update(bus_one_.get(), bus_one_->frames()); original_hash.Update(bus_two_.get(), bus_two_->frames()); AudioHash reordered_hash; reordered_hash.Update(bus_two_.get(), bus_two_->frames()); reordered_hash.Update(bus_one_.get(), bus_one_->frames()); EXPECT_NE(original_hash.ToString(), reordered_hash.ToString()); } // Ensure bus order matters to the hash even with empty buses. TEST_F(AudioHashTest, EmptyBusOrder) { bus_one_->Zero(); bus_two_->Zero(); AudioHash one_bus_hash; one_bus_hash.Update(bus_one_.get(), bus_one_->frames()); AudioHash two_bus_hash; two_bus_hash.Update(bus_one_.get(), bus_one_->frames()); two_bus_hash.Update(bus_two_.get(), bus_two_->frames()); EXPECT_NE(one_bus_hash.ToString(), two_bus_hash.ToString()); } // Where A = [0, n], ensure hash(A[0:n/2]), hash(A[n/2:n]) and hash(A) result // in the same value. TEST_F(AudioHashTest, HashIgnoresUpdateOrder) { AudioHash full_hash; full_hash.Update(bus_one_.get(), bus_one_->frames()); AudioHash half_hash; half_hash.Update(bus_one_.get(), bus_one_->frames() / 2); // Create a new bus representing the second half of |bus_one_|. const int half_frames = bus_one_->frames() / 2; const int channels = bus_one_->channels(); std::unique_ptr half_bus = AudioBus::CreateWrapper(channels); half_bus->set_frames(half_frames); for (int i = 0; i < channels; ++i) half_bus->SetChannelData(i, bus_one_->channel(i) + half_frames); half_hash.Update(half_bus.get(), half_bus->frames()); EXPECT_EQ(full_hash.ToString(), half_hash.ToString()); } // Ensure approximate hashes pass verification. TEST_F(AudioHashTest, VerifySimilarHash) { AudioHash hash_one; hash_one.Update(bus_one_.get(), bus_one_->frames()); // Twiddle the values inside the first bus. float* channel = bus_one_->channel(0); for (int i = 0; i < bus_one_->frames(); i += bus_one_->frames() / 64) channel[i] += 0.0001f; AudioHash hash_two; hash_two.Update(bus_one_.get(), bus_one_->frames()); EXPECT_EQ(hash_one.ToString(), hash_two.ToString()); // Twiddle the values too much... for (int i = 0; i < bus_one_->frames(); ++i) channel[i] += 0.0001f; AudioHash hash_three; hash_three.Update(bus_one_.get(), bus_one_->frames()); EXPECT_NE(hash_one.ToString(), hash_three.ToString()); } } // namespace media