text: /*
   *  Copyright (c) 2011 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.
   */
  
  #ifndef WEBRTC_VOICE_ENGINE_LEVEL_INDICATOR_H
  #define WEBRTC_VOICE_ENGINE_LEVEL_INDICATOR_H
  
  #include "webrtc/base/criticalsection.h"
  #include "webrtc/typedefs.h"
  
  namespace webrtc {
  
  class AudioFrame;
  namespace voe {
  
  class AudioLevel
  {
  public:
      AudioLevel();
      virtual ~AudioLevel();
  
      // Called on "API thread(s)" from APIs like VoEBase::CreateChannel(),
      // VoEBase::StopSend(), VoEVolumeControl::GetSpeechOutputLevel().
      int8_t Level() const;
      int16_t LevelFullRange() const;
      void Clear();
  
      // Called on a native capture audio thread (platform dependent) from the
      // AudioTransport::RecordedDataIsAvailable() callback.
      // In Chrome, this method is called on the AudioInputDevice thread.
      void ComputeLevel(const AudioFrame& audioFrame);
  
  private:
      enum { kUpdateFrequency = 10};
  
      rtc::CriticalSection _critSect;
  
      int16_t _absMax;
      int16_t _count;
      int8_t _currentLevel;
      int16_t _currentLevelFullRange;
  };
  
  }  // namespace voe
  
  }  // namespace webrtc
  
  #endif // WEBRTC_VOICE_ENGINE_LEVEL_INDICATOR_H
  