Create a private API for controlling WebRTC's AEC3

content/renderer/media/media_stream_audio_processor.cc

 // 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 "content/renderer/media/media_stream_audio_processor.h"
 
 #include <stddef.h>
 #include <stdint.h>
 #include <utility>
 
@@ skipping 468 matching lines @@
   else
     file.Close();
 }
 
 void MediaStreamAudioProcessor::OnDisableAecDump() {
   DCHECK(main_thread_runner_->BelongsToCurrentThread());
   if (audio_processing_)
     StopEchoCancellationDump(audio_processing_.get());
 }
 
+void MediaStreamAudioProcessor::OnAec3Enable(bool enable) {
+  DCHECK(main_thread_runner_->BelongsToCurrentThread());
+  if (override_aec3_ == base::Optional<bool>(enable))

[Henrik Grunell, 2017/04/10 17:08:40]

Nit: can be written
if (override_aec3_ == enable)

[hlundin-chromium, 2017/04/11 09:19:37]

Done.

+    return;
+
+  override_aec3_ = base::Optional<bool>(enable);

[Henrik Grunell, 2017/04/10 17:08:40]

Nit: override_aec3_ = enable;

[hlundin-chromium, 2017/04/11 09:19:37]

Done.

+  if (!has_echo_cancellation_)
+    return;
+
+  auto apm_config = audio_processing_->GetConfig();
+  if (apm_config.echo_canceller3.enabled == enable)
+    return;
+
+  apm_config.echo_canceller3.enabled = enable;
+  audio_processing_->ApplyConfig(apm_config);
+  DCHECK(echo_information_);
+  echo_information_.reset(new EchoInformation());
+}
+
 void MediaStreamAudioProcessor::OnIpcClosing() {
   DCHECK(main_thread_runner_->BelongsToCurrentThread());
   aec_dump_message_filter_ = NULL;
 }
 
 // static
 bool MediaStreamAudioProcessor::WouldModifyAudio(
     const blink::WebMediaConstraints& constraints,
     int effects_flags) {
   // Note: This method should by kept in-sync with any changes to the logic in
@@ skipping 90 matching lines @@
 
   MediaAudioConstraints audio_constraints(constraints, input_params.effects);
 
   // Note: The audio mirroring constraint (i.e., swap left and right channels)
   // is handled within this MediaStreamAudioProcessor and does not, by itself,
   // require webrtc::AudioProcessing.
   audio_mirroring_ = audio_constraints.GetGoogAudioMirroring();
 
   const bool echo_cancellation =
       audio_constraints.GetEchoCancellationProperty();
+  has_echo_cancellation_ = echo_cancellation;
   const bool goog_agc = audio_constraints.GetGoogAutoGainControl();
 
 #if defined(OS_ANDROID)
   const bool goog_experimental_aec = false;
   const bool goog_typing_detection = false;
 #else
   const bool goog_experimental_aec =
       audio_constraints.GetGoogExperimentalEchoCancellation();
   const bool goog_typing_detection =
       audio_constraints.GetGoogTypingNoiseDetection();
@@ skipping 64 matching lines @@
   }
 
   if (echo_cancellation) {
     EnableEchoCancellation(audio_processing_.get());
 
     // Prepare for logging echo information. If there are data remaining in
     // |echo_information_| we simply discard it.
     echo_information_.reset(new EchoInformation());
 
     apm_config.echo_canceller3.enabled =
-        base::FeatureList::IsEnabled(features::kWebRtcUseEchoCanceller3);
+        override_aec3_
+            ? *override_aec3_
+            : base::FeatureList::IsEnabled(features::kWebRtcUseEchoCanceller3);
   } else {
     apm_config.echo_canceller3.enabled = false;
   }
 
   if (goog_ns) {
     // The beamforming postfilter is effective at suppressing stationary noise,
     // so reduce the single-channel NS aggressiveness when enabled.
     const NoiseSuppression::Level ns_level =
         config.Get<webrtc::Beamforming>().enabled ? NoiseSuppression::kLow
                                                   : NoiseSuppression::kHigh;
@@ skipping 176 matching lines @@
       0 : agc->stream_analog_level();
 }
 
 void MediaStreamAudioProcessor::UpdateAecStats() {
   DCHECK(main_thread_runner_->BelongsToCurrentThread());
   if (echo_information_)
     echo_information_->UpdateAecStats(audio_processing_->echo_cancellation());
 }
 
 }  // namespace content