AEC3: Using a more conservative frequency response representation of …

…the tails. (cherry picked from commit 5eb5bb5) Bug: chromium:1249867 Change-Id: Ic469f6226fe079c306cec6f941eeb70d6d9094f3 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/231682 Commit-Queue: Jesus de Vicente Pena <devicentepena@webrtc.org> Reviewed-by: Per Åhgren <peah@webrtc.org> Cr-Original-Commit-Position: refs/heads/main@{#34966} Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/232322 Cr-Commit-Position: refs/branch-heads/4638@{#1} Cr-Branched-From: fb50179-refs/heads/main@{#34960}
webrtc-sdk · Sep 17, 2021 · 494c787 · 494c787
1 parent fb50179
commit 494c787
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Showing 6 changed files with 30 additions and 4 deletions.
diff --git a/api/audio/echo_canceller3_config.h b/api/audio/echo_canceller3_config.h
@@ -112,6 +112,7 @@ struct RTC_EXPORT EchoCanceller3Config {
     bool echo_can_saturate = true;
     bool bounded_erl = false;
     bool erle_onset_compensation_in_dominant_nearend = false;
+    bool use_conservative_tail_frequency_response = false;
   } ep_strength;
 
   struct EchoAudibility {

diff --git a/api/audio/echo_canceller3_config_json.cc b/api/audio/echo_canceller3_config_json.cc
@@ -264,6 +264,8 @@ void Aec3ConfigFromJsonString(absl::string_view json_string,
     ReadParam(section, "bounded_erl", &cfg.ep_strength.bounded_erl);
     ReadParam(section, "erle_onset_compensation_in_dominant_nearend",
               &cfg.ep_strength.erle_onset_compensation_in_dominant_nearend);
+    ReadParam(section, "use_conservative_tail_frequency_response",
+              &cfg.ep_strength.use_conservative_tail_frequency_response);
   }
 
   if (rtc::GetValueFromJsonObject(aec3_root, "echo_audibility", &section)) {
@@ -568,6 +570,10 @@ std::string Aec3ConfigToJsonString(const EchoCanceller3Config& config) {
       << (config.ep_strength.bounded_erl ? "true" : "false") << ",";
   ost << "\"erle_onset_compensation_in_dominant_nearend\": "
       << (config.ep_strength.erle_onset_compensation_in_dominant_nearend
+              ? "true"
+              : "false") << ",";
+  ost << "\"use_conservative_tail_frequency_response\": "
+      << (config.ep_strength.use_conservative_tail_frequency_response
               ? "true"
               : "false");
   ost << "},";

diff --git a/modules/audio_processing/aec3/echo_canceller3.cc b/modules/audio_processing/aec3/echo_canceller3.cc
@@ -286,6 +286,10 @@ EchoCanceller3Config AdjustConfig(const EchoCanceller3Config& config) {
         static_cast<float>(nearend_reverb_nearend_len.Get());
   }
 
+  if (field_trial::IsEnabled("WebRTC-Aec3ConservativeTailFreqResponse")) {
+    adjusted_cfg.ep_strength.use_conservative_tail_frequency_response = true;
+  }
+
   if (field_trial::IsEnabled("WebRTC-Aec3ShortHeadroomKillSwitch")) {
     // Two blocks headroom.
     adjusted_cfg.delay.delay_headroom_samples = kBlockSize * 2;

diff --git a/modules/audio_processing/aec3/reverb_frequency_response.cc b/modules/audio_processing/aec3/reverb_frequency_response.cc
@@ -49,9 +49,13 @@ float AverageDecayWithinFilter(
 
 }  // namespace
 
-ReverbFrequencyResponse::ReverbFrequencyResponse() {
-  tail_response_.fill(0.f);
+ReverbFrequencyResponse::ReverbFrequencyResponse(
+    bool use_conservative_tail_frequency_response)
+    : use_conservative_tail_frequency_response_(
+          use_conservative_tail_frequency_response) {
+  tail_response_.fill(0.0f);
 }
+
 ReverbFrequencyResponse::~ReverbFrequencyResponse() = default;
 
 void ReverbFrequencyResponse::Update(
@@ -88,6 +92,12 @@ void ReverbFrequencyResponse::Update(
     tail_response_[k] = freq_resp_direct_path[k] * average_decay_;
   }
 
+  if (use_conservative_tail_frequency_response_) {
+    for (size_t k = 0; k < kFftLengthBy2Plus1; ++k) {
+      tail_response_[k] = std::max(freq_resp_tail[k], tail_response_[k]);
+    }
+  }
+
   for (size_t k = 1; k < kFftLengthBy2; ++k) {
     const float avg_neighbour =
         0.5f * (tail_response_[k - 1] + tail_response_[k + 1]);

diff --git a/modules/audio_processing/aec3/reverb_frequency_response.h b/modules/audio_processing/aec3/reverb_frequency_response.h
@@ -23,7 +23,8 @@ namespace webrtc {
 // Class for updating the frequency response for the reverb.
 class ReverbFrequencyResponse {
  public:
-  ReverbFrequencyResponse();
+  explicit ReverbFrequencyResponse(
+      bool use_conservative_tail_frequency_response);
   ~ReverbFrequencyResponse();
 
   // Updates the frequency response estimate of the reverb.
@@ -44,6 +45,7 @@ class ReverbFrequencyResponse {
               int filter_delay_blocks,
               float linear_filter_quality);
 
+  const bool use_conservative_tail_frequency_response_;
   float average_decay_ = 0.f;
   std::array<float, kFftLengthBy2Plus1> tail_response_;
 };

diff --git a/modules/audio_processing/aec3/reverb_model_estimator.cc b/modules/audio_processing/aec3/reverb_model_estimator.cc
@@ -15,7 +15,10 @@ namespace webrtc {
 ReverbModelEstimator::ReverbModelEstimator(const EchoCanceller3Config& config,
                                            size_t num_capture_channels)
     : reverb_decay_estimators_(num_capture_channels),
-      reverb_frequency_responses_(num_capture_channels) {
+      reverb_frequency_responses_(
+          num_capture_channels,
+          ReverbFrequencyResponse(
+              config.ep_strength.use_conservative_tail_frequency_response)) {
   for (size_t ch = 0; ch < reverb_decay_estimators_.size(); ++ch) {
     reverb_decay_estimators_[ch] =
         std::make_unique<ReverbDecayEstimator>(config);