Remove unused code in APM

- The injection of the AGC2 level estimator into `AgcManagerDirect`
  is not used anymore
- `ExperimentalAgc::enabled_agc2_level_estimator` can also be removed
- 3 ctors of `ExperimentalAgc` are unused
- `AgcManagerDirectStandaloneTest::AgcMinMicLevelExperiment` can be
  split into separate unit tests (better code clarity)

Bug: webrtc:7494
Change-Id: I5843147c38cf7cb5ee484b0a72fe13dcf363efaf
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/202025
Commit-Queue: Alessio Bazzica <[email protected]>
Reviewed-by: Per Åhgren <[email protected]>
Cr-Commit-Position: refs/heads/master@{#33027}

modules/audio_processing/agc/BUILD.gn

@@ -33,7 +33,6 @@ rtc_library("agc") {
     "../../../rtc_base:safe_minmax",
     "../../../system_wrappers:field_trial",
     "../../../system_wrappers:metrics",
-    "../agc2:level_estimation_agc",
     "../vad",
   ]
   absl_deps = [ "//third_party/abseil-cpp/absl/types:optional" ]

modules/audio_processing/agc/agc_manager_direct.cc

@@ -16,7 +16,6 @@
 #include "common_audio/include/audio_util.h"
 #include "modules/audio_processing/agc/gain_control.h"
 #include "modules/audio_processing/agc/gain_map_internal.h"
-#include "modules/audio_processing/agc2/adaptive_mode_level_estimator_agc.h"
 #include "rtc_base/atomic_ops.h"
 #include "rtc_base/checks.h"
 #include "rtc_base/logging.h"
@@ -138,24 +137,18 @@ float ComputeClippedRatio(const float* const* audio,
 MonoAgc::MonoAgc(ApmDataDumper* data_dumper,
                  int startup_min_level,
                  int clipped_level_min,
-                 bool use_agc2_level_estimation,
                  bool disable_digital_adaptive,
                  int min_mic_level)
     : min_mic_level_(min_mic_level),
       disable_digital_adaptive_(disable_digital_adaptive),
+      agc_(std::make_unique<Agc>()),
       max_level_(kMaxMicLevel),
       max_compression_gain_(kMaxCompressionGain),
       target_compression_(kDefaultCompressionGain),
       compression_(target_compression_),
       compression_accumulator_(compression_),
       startup_min_level_(ClampLevel(startup_min_level, min_mic_level_)),
-      clipped_level_min_(clipped_level_min) {
-  if (use_agc2_level_estimation) {
-    agc_ = std::make_unique<AdaptiveModeLevelEstimatorAgc>(data_dumper);
-  } else {
-    agc_ = std::make_unique<Agc>();
-  }
-}
+      clipped_level_min_(clipped_level_min) {}
 
 MonoAgc::~MonoAgc() = default;
 
@@ -415,7 +408,6 @@ AgcManagerDirect::AgcManagerDirect(Agc* agc,
     : AgcManagerDirect(/*num_capture_channels*/ 1,
                        startup_min_level,
                        clipped_level_min,
-                       /*use_agc2_level_estimation*/ false,
                        /*disable_digital_adaptive*/ false,
                        sample_rate_hz) {
   RTC_DCHECK(channel_agcs_[0]);
@@ -426,7 +418,6 @@ AgcManagerDirect::AgcManagerDirect(Agc* agc,
 AgcManagerDirect::AgcManagerDirect(int num_capture_channels,
                                    int startup_min_level,
                                    int clipped_level_min,
-                                   bool use_agc2_level_estimation,
                                    bool disable_digital_adaptive,
                                    int sample_rate_hz)
     : data_dumper_(
@@ -445,7 +436,7 @@ AgcManagerDirect::AgcManagerDirect(int num_capture_channels,
 
     channel_agcs_[ch] = std::make_unique<MonoAgc>(
         data_dumper_ch, startup_min_level, clipped_level_min,
-        use_agc2_level_estimation, disable_digital_adaptive_, min_mic_level);
+        disable_digital_adaptive_, min_mic_level);
   }
   RTC_DCHECK_LT(0, channel_agcs_.size());
   channel_agcs_[0]->ActivateLogging();

modules/audio_processing/agc/agc_manager_direct.h

@@ -38,7 +38,6 @@ class AgcManagerDirect final {
   AgcManagerDirect(int num_capture_channels,
                    int startup_min_level,
                    int clipped_level_min,
-                   bool use_agc2_level_estimation,
                    bool disable_digital_adaptive,
                    int sample_rate_hz);
 
@@ -73,6 +72,16 @@ class AgcManagerDirect final {
                            DisableDigitalDisablesDigital);
   FRIEND_TEST_ALL_PREFIXES(AgcManagerDirectStandaloneTest,
                            AgcMinMicLevelExperiment);
+  FRIEND_TEST_ALL_PREFIXES(AgcManagerDirectStandaloneTest,
+                           AgcMinMicLevelExperimentDisabled);
+  FRIEND_TEST_ALL_PREFIXES(AgcManagerDirectStandaloneTest,
+                           AgcMinMicLevelExperimentOutOfRangeAbove);
+  FRIEND_TEST_ALL_PREFIXES(AgcManagerDirectStandaloneTest,
+                           AgcMinMicLevelExperimentOutOfRangeBelow);
+  FRIEND_TEST_ALL_PREFIXES(AgcManagerDirectStandaloneTest,
+                           AgcMinMicLevelExperimentEnabled50);
+  FRIEND_TEST_ALL_PREFIXES(AgcManagerDirectStandaloneTest,
+                           AgcMinMicLevelExperimentEnabledAboveStartupLevel);
 
   // Dependency injection for testing. Don't delete |agc| as the memory is owned
   // by the manager.
@@ -106,7 +115,6 @@ class MonoAgc {
   MonoAgc(ApmDataDumper* data_dumper,
           int startup_min_level,
           int clipped_level_min,
-          bool use_agc2_level_estimation,
           bool disable_digital_adaptive,
           int min_mic_level);
   ~MonoAgc();

modules/audio_processing/agc/agc_manager_direct_unittest.cc

@@ -56,6 +56,13 @@ class MockGainControl : public GainControl {
   MOCK_METHOD(bool, stream_is_saturated, (), (const, override));
 };
 
+std::unique_ptr<AgcManagerDirect> CreateAgcManagerDirect(
+    int startup_min_level) {
+  return std::make_unique<AgcManagerDirect>(
+      /*num_capture_channels=*/1, startup_min_level, kClippedMin,
+      /*disable_digital_adaptive=*/true, kSampleRateHz);
+}
+
 }  // namespace
 
 class AgcManagerDirectTest : public ::testing::Test {
@@ -692,77 +699,78 @@ TEST_F(AgcManagerDirectTest, TakesNoActionOnZeroMicVolume) {
 TEST(AgcManagerDirectStandaloneTest, DisableDigitalDisablesDigital) {
   auto agc = std::unique_ptr<Agc>(new ::testing::NiceMock<MockAgc>());
   MockGainControl gctrl;
-  AgcManagerDirect manager(/* num_capture_channels */ 1, kInitialVolume,
-                           kClippedMin,
-                           /* use agc2 level estimation */ false,
-                           /* disable digital adaptive */ true, kSampleRateHz);
-
   EXPECT_CALL(gctrl, set_mode(GainControl::kFixedDigital));
   EXPECT_CALL(gctrl, set_target_level_dbfs(0));
   EXPECT_CALL(gctrl, set_compression_gain_db(0));
   EXPECT_CALL(gctrl, enable_limiter(false));
 
-  manager.Initialize();
-  manager.SetupDigitalGainControl(&gctrl);
+  std::unique_ptr<AgcManagerDirect> manager =
+      CreateAgcManagerDirect(kInitialVolume);
+  manager->Initialize();
+  manager->SetupDigitalGainControl(&gctrl);
 }
 
 TEST(AgcManagerDirectStandaloneTest, AgcMinMicLevelExperiment) {
-  auto agc_man = std::unique_ptr<AgcManagerDirect>(new AgcManagerDirect(
-      /* num_capture_channels */ 1, kInitialVolume, kClippedMin, true, true,
-      kSampleRateHz));
-  EXPECT_EQ(agc_man->channel_agcs_[0]->min_mic_level(), kMinMicLevel);
-  EXPECT_EQ(agc_man->channel_agcs_[0]->startup_min_level(), kInitialVolume);
-  {
-    test::ScopedFieldTrials field_trial(
-        "WebRTC-Audio-AgcMinMicLevelExperiment/Disabled/");
-    agc_man.reset(new AgcManagerDirect(
-        /* num_capture_channels */ 1, kInitialVolume, kClippedMin, true, true,
-        kSampleRateHz));
-    EXPECT_EQ(agc_man->channel_agcs_[0]->min_mic_level(), kMinMicLevel);
-    EXPECT_EQ(agc_man->channel_agcs_[0]->startup_min_level(), kInitialVolume);
-  }
-  {
-    // Valid range of field-trial parameter is [0,255].
-    test::ScopedFieldTrials field_trial(
-        "WebRTC-Audio-AgcMinMicLevelExperiment/Enabled-256/");
-    agc_man.reset(new AgcManagerDirect(
-        /* num_capture_channels */ 1, kInitialVolume, kClippedMin, true, true,
-        kSampleRateHz));
-    EXPECT_EQ(agc_man->channel_agcs_[0]->min_mic_level(), kMinMicLevel);
-    EXPECT_EQ(agc_man->channel_agcs_[0]->startup_min_level(), kInitialVolume);
-  }
-  {
-    test::ScopedFieldTrials field_trial(
-        "WebRTC-Audio-AgcMinMicLevelExperiment/Enabled--1/");
-    agc_man.reset(new AgcManagerDirect(
-        /* num_capture_channels */ 1, kInitialVolume, kClippedMin, true, true,
-        kSampleRateHz));
-    EXPECT_EQ(agc_man->channel_agcs_[0]->min_mic_level(), kMinMicLevel);
-    EXPECT_EQ(agc_man->channel_agcs_[0]->startup_min_level(), kInitialVolume);
-  }
-  {
-    // Verify that a valid experiment changes the minimum microphone level.
-    // The start volume is larger than the min level and should therefore not
-    // be changed.
-    test::ScopedFieldTrials field_trial(
-        "WebRTC-Audio-AgcMinMicLevelExperiment/Enabled-50/");
-    agc_man.reset(new AgcManagerDirect(
-        /* num_capture_channels */ 1, kInitialVolume, kClippedMin, true, true,
-        kSampleRateHz));
-    EXPECT_EQ(agc_man->channel_agcs_[0]->min_mic_level(), 50);
-    EXPECT_EQ(agc_man->channel_agcs_[0]->startup_min_level(), kInitialVolume);
-  }
-  {
-    // Use experiment to reduce the default minimum microphone level, start at
-    // a lower level and ensure that the startup level is increased to the min
-    // level set by the experiment.
-    test::ScopedFieldTrials field_trial(
-        "WebRTC-Audio-AgcMinMicLevelExperiment/Enabled-50/");
-    agc_man.reset(new AgcManagerDirect(/* num_capture_channels */ 1, 30,
-                                       kClippedMin, true, true, kSampleRateHz));
-    EXPECT_EQ(agc_man->channel_agcs_[0]->min_mic_level(), 50);
-    EXPECT_EQ(agc_man->channel_agcs_[0]->startup_min_level(), 50);
-  }
+  std::unique_ptr<AgcManagerDirect> manager =
+      CreateAgcManagerDirect(kInitialVolume);
+  EXPECT_EQ(manager->channel_agcs_[0]->min_mic_level(), kMinMicLevel);
+  EXPECT_EQ(manager->channel_agcs_[0]->startup_min_level(), kInitialVolume);
+}
+
+TEST(AgcManagerDirectStandaloneTest, AgcMinMicLevelExperimentDisabled) {
+  test::ScopedFieldTrials field_trial(
+      "WebRTC-Audio-AgcMinMicLevelExperiment/Disabled/");
+  std::unique_ptr<AgcManagerDirect> manager =
+      CreateAgcManagerDirect(kInitialVolume);
+  EXPECT_EQ(manager->channel_agcs_[0]->min_mic_level(), kMinMicLevel);
+  EXPECT_EQ(manager->channel_agcs_[0]->startup_min_level(), kInitialVolume);
+}
+
+// Checks that a field-trial parameter outside of the valid range [0,255] is
+// ignored.
+TEST(AgcManagerDirectStandaloneTest, AgcMinMicLevelExperimentOutOfRangeAbove) {
+  test::ScopedFieldTrials field_trial(
+      "WebRTC-Audio-AgcMinMicLevelExperiment/Enabled-256/");
+  std::unique_ptr<AgcManagerDirect> manager =
+      CreateAgcManagerDirect(kInitialVolume);
+  EXPECT_EQ(manager->channel_agcs_[0]->min_mic_level(), kMinMicLevel);
+  EXPECT_EQ(manager->channel_agcs_[0]->startup_min_level(), kInitialVolume);
+}
+
+// Checks that a field-trial parameter outside of the valid range [0,255] is
+// ignored.
+TEST(AgcManagerDirectStandaloneTest, AgcMinMicLevelExperimentOutOfRangeBelow) {
+  test::ScopedFieldTrials field_trial(
+      "WebRTC-Audio-AgcMinMicLevelExperiment/Enabled--1/");
+  std::unique_ptr<AgcManagerDirect> manager =
+      CreateAgcManagerDirect(kInitialVolume);
+  EXPECT_EQ(manager->channel_agcs_[0]->min_mic_level(), kMinMicLevel);
+  EXPECT_EQ(manager->channel_agcs_[0]->startup_min_level(), kInitialVolume);
+}
+
+// Verifies that a valid experiment changes the minimum microphone level. The
+// start volume is larger than the min level and should therefore not be
+// changed.
+TEST(AgcManagerDirectStandaloneTest, AgcMinMicLevelExperimentEnabled50) {
+  test::ScopedFieldTrials field_trial(
+      "WebRTC-Audio-AgcMinMicLevelExperiment/Enabled-50/");
+  std::unique_ptr<AgcManagerDirect> manager =
+      CreateAgcManagerDirect(kInitialVolume);
+  EXPECT_EQ(manager->channel_agcs_[0]->min_mic_level(), 50);
+  EXPECT_EQ(manager->channel_agcs_[0]->startup_min_level(), kInitialVolume);
+}
+
+// Uses experiment to reduce the default minimum microphone level, start at a
+// lower level and ensure that the startup level is increased to the min level
+// set by the experiment.
+TEST(AgcManagerDirectStandaloneTest,
+     AgcMinMicLevelExperimentEnabledAboveStartupLevel) {
+  test::ScopedFieldTrials field_trial(
+      "WebRTC-Audio-AgcMinMicLevelExperiment/Enabled-50/");
+  std::unique_ptr<AgcManagerDirect> manager =
+      CreateAgcManagerDirect(/*startup_min_level=*/30);
+  EXPECT_EQ(manager->channel_agcs_[0]->min_mic_level(), 50);
+  EXPECT_EQ(manager->channel_agcs_[0]->startup_min_level(), 50);
 }
 
 }  // namespace webrtc

modules/audio_processing/agc2/BUILD.gn

@@ -15,31 +15,6 @@ group("agc2") {
   ]
 }
 
-rtc_library("level_estimation_agc") {
-  sources = [
-    "adaptive_mode_level_estimator_agc.cc",
-    "adaptive_mode_level_estimator_agc.h",
-  ]
-  configs += [ "..:apm_debug_dump" ]
-  deps = [
-    ":adaptive_digital",
-    ":common",
-    ":gain_applier",
-    ":noise_level_estimator",
-    ":rnn_vad_with_level",
-    "..:api",
-    "..:apm_logging",
-    "..:audio_frame_view",
-    "../../../api:array_view",
-    "../../../common_audio",
-    "../../../rtc_base:checks",
-    "../../../rtc_base:rtc_base_approved",
-    "../../../rtc_base:safe_minmax",
-    "../agc:level_estimation",
-    "../vad",
-  ]
-}
-
 rtc_library("adaptive_digital") {
   sources = [
     "adaptive_agc.cc",