Improved tuning of the adaptive level controller.

webrtc/modules/audio_processing/level_controller/gain_applier.h

 /*
  *  Copyright (c) 2016 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 12 matching lines @@
   explicit GainApplier(ApmDataDumper* data_dumper);
   void Initialize(int sample_rate_hz);
 
   // Applies the specified gain to the audio frame and returns the resulting
   // number of saturated sample values.
   int Process(float new_gain, AudioBuffer* audio);
 
  private:
   ApmDataDumper* const data_dumper_;
   float old_gain_ = 1.f;
-  float gain_change_step_size_ = 0.f;
-
+  float gain_increase_step_size_ = 0.f;
+  float gain_normal_decrease_step_size_ = 0.f;
+  float gain_saturated_decrease_step_size_ = 0.f;
+  bool last_frame_was_saturated_;
   RTC_DISALLOW_IMPLICIT_CONSTRUCTORS(GainApplier);
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_AUDIO_PROCESSING_LEVEL_CONTROLLER_GAIN_APPLIER_H_