text: /*
   *  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.
   */
  
  #include "webrtc/modules/audio_processing/level_estimator_impl.h"
  
  #include "webrtc/modules/audio_processing/audio_buffer.h"
  #include "webrtc/modules/audio_processing/include/audio_processing.h"
  #include "webrtc/system_wrappers/interface/critical_section_wrapper.h"
  
  namespace webrtc {
  
  LevelEstimatorImpl::LevelEstimatorImpl(const AudioProcessing* apm,
                                         CriticalSectionWrapper* crit)
      : ProcessingComponent(),
        crit_(crit) {}
  
  LevelEstimatorImpl::~LevelEstimatorImpl() {}
  
  int LevelEstimatorImpl::ProcessStream(AudioBuffer* audio) {
    if (!is_component_enabled()) {
      return AudioProcessing::kNoError;
    }
  
    RMSLevel* rms_level = static_cast<RMSLevel*>(handle(0));
    if (audio->is_muted()) {
      rms_level->ProcessMuted(audio->samples_per_channel() *
                              audio->num_channels());
    } else {
      for (int i = 0; i < audio->num_channels(); ++i) {
        rms_level->Process(audio->data(i), audio->samples_per_channel());
      }
    }
  
    return AudioProcessing::kNoError;
  }
  
  int LevelEstimatorImpl::Enable(bool enable) {
    CriticalSectionScoped crit_scoped(crit_);
    return EnableComponent(enable);
  }
  
  bool LevelEstimatorImpl::is_enabled() const {
    return is_component_enabled();
  }
  
  int LevelEstimatorImpl::RMS() {
    if (!is_component_enabled()) {
      return AudioProcessing::kNotEnabledError;
    }
  
    RMSLevel* rms_level = static_cast<RMSLevel*>(handle(0));
    return rms_level->RMS();
  }
  
  // The ProcessingComponent implementation is pretty weird in this class since
  // we have only a single instance of the trivial underlying component.
  void* LevelEstimatorImpl::CreateHandle() const {
    return new RMSLevel;
  }
  
  void LevelEstimatorImpl::DestroyHandle(void* handle) const {
    delete static_cast<RMSLevel*>(handle);
  }
  
  int LevelEstimatorImpl::InitializeHandle(void* handle) const {
    static_cast<RMSLevel*>(handle)->Reset();
    return AudioProcessing::kNoError;
  }
  
  int LevelEstimatorImpl::ConfigureHandle(void* /*handle*/) const {
    return AudioProcessing::kNoError;
  }
  
  int LevelEstimatorImpl::num_handles_required() const {
    return 1;
  }
  
  int LevelEstimatorImpl::GetHandleError(void* /*handle*/) const {
    return AudioProcessing::kUnspecifiedError;
  }
  
  }  // namespace webrtc
  