New module for the adaptive level controlling functionality in the audio processing module

webrtc/modules/audio_processing/include/audio_processing.h

 /*
  *  Copyright (c) 2012 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.
  */
 
@@ skipping 74 matching lines @@
 // EchoControlMobile. It can be set in the constructor
 // or using AudioProcessing::SetExtraOptions().
 struct RefinedAdaptiveFilter {
   RefinedAdaptiveFilter() : enabled(false) {}
   explicit RefinedAdaptiveFilter(bool enabled) : enabled(enabled) {}
   static const ConfigOptionID identifier =
       ConfigOptionID::kAecRefinedAdaptiveFilter;
   bool enabled;
 };
 
+// Enables the adaptive level controller.
+struct LevelControl {
+  LevelControl() : enabled(false) {}
+  explicit LevelControl(bool enabled) : enabled(enabled) {}
+  static const ConfigOptionID identifier = ConfigOptionID::kLevelControl;
+  bool enabled;
+};
+
 // Enables delay-agnostic echo cancellation. This feature relies on internally
 // estimated delays between the process and reverse streams, thus not relying
 // on reported system delays. This configuration only applies to
 // EchoCancellation and not EchoControlMobile. It can be set in the constructor
 // or using AudioProcessing::SetExtraOptions().
 struct DelayAgnostic {
   DelayAgnostic() : enabled(false) {}
   explicit DelayAgnostic(bool enabled) : enabled(enabled) {}
   static const ConfigOptionID identifier = ConfigOptionID::kDelayAgnostic;
   bool enabled;
@@ skipping 873 matching lines @@
   // This does not impact the size of frames passed to |ProcessStream()|.
   virtual int set_frame_size_ms(int size) = 0;
   virtual int frame_size_ms() const = 0;
 
  protected:
   virtual ~VoiceDetection() {}
 };
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_AUDIO_PROCESSING_INCLUDE_AUDIO_PROCESSING_H_