|  | /* | 
|  | *  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 <algorithm> | 
|  |  | 
|  | #include "absl/memory/memory.h" | 
|  | #include "api/array_view.h" | 
|  | #include "modules/audio_processing/agc2/agc2_testing_common.h" | 
|  | #include "modules/audio_processing/audio_buffer.h" | 
|  | #include "modules/audio_processing/gain_controller2.h" | 
|  | #include "modules/audio_processing/test/audio_buffer_tools.h" | 
|  | #include "modules/audio_processing/test/bitexactness_tools.h" | 
|  | #include "rtc_base/checks.h" | 
|  | #include "test/gtest.h" | 
|  |  | 
|  | namespace webrtc { | 
|  | namespace test { | 
|  | namespace { | 
|  |  | 
|  | void SetAudioBufferSamples(float value, AudioBuffer* ab) { | 
|  | // Sets all the samples in |ab| to |value|. | 
|  | for (size_t k = 0; k < ab->num_channels(); ++k) { | 
|  | std::fill(ab->channels_f()[k], ab->channels_f()[k] + ab->num_frames(), | 
|  | value); | 
|  | } | 
|  | } | 
|  |  | 
|  | float RunAgc2WithConstantInput(GainController2* agc2, | 
|  | float input_level, | 
|  | size_t num_frames, | 
|  | int sample_rate) { | 
|  | const int num_samples = rtc::CheckedDivExact(sample_rate, 100); | 
|  | AudioBuffer ab(num_samples, 1, num_samples, 1, num_samples); | 
|  |  | 
|  | // Give time to the level estimator to converge. | 
|  | for (size_t i = 0; i < num_frames + 1; ++i) { | 
|  | SetAudioBufferSamples(input_level, &ab); | 
|  | agc2->Process(&ab); | 
|  | } | 
|  |  | 
|  | // Return the last sample from the last processed frame. | 
|  | return ab.channels_f()[0][num_samples - 1]; | 
|  | } | 
|  |  | 
|  | AudioProcessing::Config::GainController2 CreateAgc2FixedDigitalModeConfig( | 
|  | float fixed_gain_db) { | 
|  | AudioProcessing::Config::GainController2 config; | 
|  | config.adaptive_digital.enabled = false; | 
|  | config.fixed_digital.gain_db = fixed_gain_db; | 
|  | // TODO(alessiob): Check why ASSERT_TRUE() below does not compile. | 
|  | EXPECT_TRUE(GainController2::Validate(config)); | 
|  | return config; | 
|  | } | 
|  |  | 
|  | std::unique_ptr<GainController2> CreateAgc2FixedDigitalMode( | 
|  | float fixed_gain_db, | 
|  | size_t sample_rate_hz) { | 
|  | auto agc2 = absl::make_unique<GainController2>(); | 
|  | agc2->ApplyConfig(CreateAgc2FixedDigitalModeConfig(fixed_gain_db)); | 
|  | agc2->Initialize(sample_rate_hz); | 
|  | return agc2; | 
|  | } | 
|  |  | 
|  | float GainAfterProcessingFile(GainController2* gain_controller) { | 
|  | // Set up an AudioBuffer to be filled from the speech file. | 
|  | constexpr size_t kStereo = 2u; | 
|  | const StreamConfig capture_config(AudioProcessing::kSampleRate48kHz, kStereo, | 
|  | false); | 
|  | AudioBuffer ab(capture_config.num_frames(), capture_config.num_channels(), | 
|  | capture_config.num_frames(), capture_config.num_channels(), | 
|  | capture_config.num_frames()); | 
|  | test::InputAudioFile capture_file( | 
|  | test::GetApmCaptureTestVectorFileName(AudioProcessing::kSampleRate48kHz)); | 
|  | std::vector<float> capture_input(capture_config.num_frames() * | 
|  | capture_config.num_channels()); | 
|  |  | 
|  | // The file should contain at least this many frames. Every iteration, we put | 
|  | // a frame through the gain controller. | 
|  | const int kNumFramesToProcess = 100; | 
|  | for (int frame_no = 0; frame_no < kNumFramesToProcess; ++frame_no) { | 
|  | ReadFloatSamplesFromStereoFile(capture_config.num_frames(), | 
|  | capture_config.num_channels(), &capture_file, | 
|  | capture_input); | 
|  |  | 
|  | test::CopyVectorToAudioBuffer(capture_config, capture_input, &ab); | 
|  | gain_controller->Process(&ab); | 
|  | } | 
|  |  | 
|  | // Send in a last frame with values constant 1 (It's low enough to detect high | 
|  | // gain, and for ease of computation). The applied gain is the result. | 
|  | constexpr float sample_value = 1.f; | 
|  | SetAudioBufferSamples(sample_value, &ab); | 
|  | gain_controller->Process(&ab); | 
|  | return ab.channels_f()[0][0]; | 
|  | } | 
|  |  | 
|  | }  // namespace | 
|  |  | 
|  | TEST(GainController2, CreateApplyConfig) { | 
|  | // Instances GainController2 and applies different configurations. | 
|  | std::unique_ptr<GainController2> gain_controller2(new GainController2()); | 
|  |  | 
|  | // Check that the default config is valid. | 
|  | AudioProcessing::Config::GainController2 config; | 
|  | EXPECT_TRUE(GainController2::Validate(config)); | 
|  | gain_controller2->ApplyConfig(config); | 
|  |  | 
|  | // Check that attenuation is not allowed. | 
|  | config.fixed_digital.gain_db = -5.f; | 
|  | EXPECT_FALSE(GainController2::Validate(config)); | 
|  |  | 
|  | // Check that valid configurations are applied. | 
|  | for (const float& fixed_gain_db : {0.f, 5.f, 10.f, 40.f}) { | 
|  | config.fixed_digital.gain_db = fixed_gain_db; | 
|  | EXPECT_TRUE(GainController2::Validate(config)); | 
|  | gain_controller2->ApplyConfig(config); | 
|  | } | 
|  | } | 
|  |  | 
|  | TEST(GainController2, ToString) { | 
|  | // Tests GainController2::ToString(). Only test the enabled property. | 
|  | AudioProcessing::Config::GainController2 config; | 
|  |  | 
|  | config.enabled = false; | 
|  | EXPECT_EQ("{enabled: false", GainController2::ToString(config).substr(0, 15)); | 
|  |  | 
|  | config.enabled = true; | 
|  | EXPECT_EQ("{enabled: true", GainController2::ToString(config).substr(0, 14)); | 
|  | } | 
|  |  | 
|  | TEST(GainController2FixedDigital, GainShouldChangeOnSetGain) { | 
|  | constexpr float kInputLevel = 1000.f; | 
|  | constexpr size_t kNumFrames = 5; | 
|  | constexpr size_t kSampleRateHz = 8000; | 
|  | constexpr float kGain0Db = 0.f; | 
|  | constexpr float kGain20Db = 20.f; | 
|  |  | 
|  | auto agc2_fixed = CreateAgc2FixedDigitalMode(kGain0Db, kSampleRateHz); | 
|  |  | 
|  | // Signal level is unchanged with 0 db gain. | 
|  | EXPECT_FLOAT_EQ(RunAgc2WithConstantInput(agc2_fixed.get(), kInputLevel, | 
|  | kNumFrames, kSampleRateHz), | 
|  | kInputLevel); | 
|  |  | 
|  | // +20 db should increase signal by a factor of 10. | 
|  | agc2_fixed->ApplyConfig(CreateAgc2FixedDigitalModeConfig(kGain20Db)); | 
|  | EXPECT_FLOAT_EQ(RunAgc2WithConstantInput(agc2_fixed.get(), kInputLevel, | 
|  | kNumFrames, kSampleRateHz), | 
|  | kInputLevel * 10); | 
|  | } | 
|  |  | 
|  | TEST(GainController2FixedDigital, ChangeFixedGainShouldBeFastAndTimeInvariant) { | 
|  | // Number of frames required for the fixed gain controller to adapt on the | 
|  | // input signal when the gain changes. | 
|  | constexpr size_t kNumFrames = 5; | 
|  |  | 
|  | constexpr float kInputLevel = 1000.f; | 
|  | constexpr size_t kSampleRateHz = 8000; | 
|  | constexpr float kGainDbLow = 0.f; | 
|  | constexpr float kGainDbHigh = 25.f; | 
|  | static_assert(kGainDbLow < kGainDbHigh, ""); | 
|  |  | 
|  | auto agc2_fixed = CreateAgc2FixedDigitalMode(kGainDbLow, kSampleRateHz); | 
|  |  | 
|  | // Start with a lower gain. | 
|  | const float output_level_pre = RunAgc2WithConstantInput( | 
|  | agc2_fixed.get(), kInputLevel, kNumFrames, kSampleRateHz); | 
|  |  | 
|  | // Increase gain. | 
|  | agc2_fixed->ApplyConfig(CreateAgc2FixedDigitalModeConfig(kGainDbHigh)); | 
|  | static_cast<void>(RunAgc2WithConstantInput(agc2_fixed.get(), kInputLevel, | 
|  | kNumFrames, kSampleRateHz)); | 
|  |  | 
|  | // Back to the lower gain. | 
|  | agc2_fixed->ApplyConfig(CreateAgc2FixedDigitalModeConfig(kGainDbLow)); | 
|  | const float output_level_post = RunAgc2WithConstantInput( | 
|  | agc2_fixed.get(), kInputLevel, kNumFrames, kSampleRateHz); | 
|  |  | 
|  | EXPECT_EQ(output_level_pre, output_level_post); | 
|  | } | 
|  |  | 
|  | struct FixedDigitalTestParams { | 
|  | FixedDigitalTestParams(float gain_db_min, | 
|  | float gain_db_max, | 
|  | size_t sample_rate, | 
|  | bool saturation_expected) | 
|  | : gain_db_min(gain_db_min), | 
|  | gain_db_max(gain_db_max), | 
|  | sample_rate(sample_rate), | 
|  | saturation_expected(saturation_expected) {} | 
|  | float gain_db_min; | 
|  | float gain_db_max; | 
|  | size_t sample_rate; | 
|  | bool saturation_expected; | 
|  | }; | 
|  |  | 
|  | class FixedDigitalTest | 
|  | : public testing::Test, | 
|  | public testing::WithParamInterface<FixedDigitalTestParams> {}; | 
|  |  | 
|  | TEST_P(FixedDigitalTest, CheckSaturationBehaviorWithLimiter) { | 
|  | const float kInputLevel = 32767.f; | 
|  | const size_t kNumFrames = 5; | 
|  |  | 
|  | const auto params = GetParam(); | 
|  |  | 
|  | const auto gains_db = | 
|  | test::LinSpace(params.gain_db_min, params.gain_db_max, 10); | 
|  | for (const auto gain_db : gains_db) { | 
|  | SCOPED_TRACE(std::to_string(gain_db)); | 
|  | auto agc2_fixed = CreateAgc2FixedDigitalMode(gain_db, params.sample_rate); | 
|  | const float processed_sample = RunAgc2WithConstantInput( | 
|  | agc2_fixed.get(), kInputLevel, kNumFrames, params.sample_rate); | 
|  | if (params.saturation_expected) { | 
|  | EXPECT_FLOAT_EQ(processed_sample, 32767.f); | 
|  | } else { | 
|  | EXPECT_LT(processed_sample, 32767.f); | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | static_assert(test::kLimiterMaxInputLevelDbFs < 10, ""); | 
|  | INSTANTIATE_TEST_CASE_P( | 
|  | GainController2, | 
|  | FixedDigitalTest, | 
|  | ::testing::Values( | 
|  | // When gain < |test::kLimiterMaxInputLevelDbFs|, the limiter will not | 
|  | // saturate the signal (at any sample rate). | 
|  | FixedDigitalTestParams(0.1f, | 
|  | test::kLimiterMaxInputLevelDbFs - 0.01f, | 
|  | 8000, | 
|  | false), | 
|  | FixedDigitalTestParams(0.1, | 
|  | test::kLimiterMaxInputLevelDbFs - 0.01f, | 
|  | 48000, | 
|  | false), | 
|  | // When gain > |test::kLimiterMaxInputLevelDbFs|, the limiter will | 
|  | // saturate the signal (at any sample rate). | 
|  | FixedDigitalTestParams(test::kLimiterMaxInputLevelDbFs + 0.01f, | 
|  | 10.f, | 
|  | 8000, | 
|  | true), | 
|  | FixedDigitalTestParams(test::kLimiterMaxInputLevelDbFs + 0.01f, | 
|  | 10.f, | 
|  | 48000, | 
|  | true))); | 
|  |  | 
|  | TEST(GainController2, UsageSaturationMargin) { | 
|  | GainController2 gain_controller2; | 
|  | gain_controller2.Initialize(AudioProcessing::kSampleRate48kHz); | 
|  |  | 
|  | AudioProcessing::Config::GainController2 config; | 
|  | // Check that samples are not amplified as much when extra margin is | 
|  | // high. They should not be amplified at all, but only after convergence. GC2 | 
|  | // starts with a gain, and it takes time until it's down to 0 dB. | 
|  | config.fixed_digital.gain_db = 0.f; | 
|  | config.adaptive_digital.enabled = true; | 
|  | config.adaptive_digital.extra_saturation_margin_db = 50.f; | 
|  | gain_controller2.ApplyConfig(config); | 
|  |  | 
|  | EXPECT_LT(GainAfterProcessingFile(&gain_controller2), 2.f); | 
|  | } | 
|  |  | 
|  | TEST(GainController2, UsageNoSaturationMargin) { | 
|  | GainController2 gain_controller2; | 
|  | gain_controller2.Initialize(AudioProcessing::kSampleRate48kHz); | 
|  |  | 
|  | AudioProcessing::Config::GainController2 config; | 
|  | // Check that some gain is applied if there is no margin. | 
|  | config.fixed_digital.gain_db = 0.f; | 
|  | config.adaptive_digital.enabled = true; | 
|  | config.adaptive_digital.extra_saturation_margin_db = 0.f; | 
|  | gain_controller2.ApplyConfig(config); | 
|  |  | 
|  | EXPECT_GT(GainAfterProcessingFile(&gain_controller2), 2.f); | 
|  | } | 
|  |  | 
|  | }  // namespace test | 
|  | }  // namespace webrtc |