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

webrtc/modules/audio_processing/level_controller/level_controller.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.
+ */
+
+#ifndef WEBRTC_MODULES_AUDIO_PROCESSING_LEVEL_CONTROLLER_LEVEL_CONTROLLER_H_
+#define WEBRTC_MODULES_AUDIO_PROCESSING_LEVEL_CONTROLLER_LEVEL_CONTROLLER_H_
+
+#include <memory>
+#include <vector>
+
+// TODO(peah): Try to remove.
+#include "webrtc/base/constructormagic.h"
+
+namespace webrtc {
+
+class ApmDataDumper;
+class AudioBuffer;
+class GainApplier;
+class GainSelector;
+class NoiseLevelEstimator;
+class PeakLevelEstimator;
+class SaturatingGainEstimator;
+class SignalClassifier;
+
+class LevelController {
+ public:
+  LevelController();
+  ~LevelController();
+
+  void Initialize(int sample_rate_hz, size_t num_channels_);

[hlundin-webrtc, 2016/06/27 11:21:15]

No trailing underscore on parameter names.

[peah-webrtc, 2016/06/27 22:51:48]

Done.

+  void Process(AudioBuffer* audio);
+
+ private:
+  std::unique_ptr<ApmDataDumper> data_dumper_;

[hlundin-webrtc, 2016/06/27 11:21:15]

Are you using unique_ptrs just to be able to forward declare rather than
#include? I don't think that counts as fair use... :)

[peah-webrtc, 2016/06/27 22:51:48]

Good point! That I definitely do. I'll change that.

+  std::unique_ptr<GainSelector> gain_selector_;
+  std::unique_ptr<GainApplier> gain_applier_;
+  std::unique_ptr<SignalClassifier> signal_classifier_;
+  std::unique_ptr<NoiseLevelEstimator> noise_level_estimator_;
+  std::unique_ptr<PeakLevelEstimator> peak_level_estimator_;
+  std::unique_ptr<SaturatingGainEstimator> saturating_gain_estimator_;
+  int sample_rate_hz_ = 8000;
+  static int instance_count_;
+  float dc_level_[2];
+
+  RTC_DISALLOW_COPY_AND_ASSIGN(LevelController);
+};
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_MODULES_AUDIO_PROCESSING_LEVEL_CONTROLLER_LEVEL_CONTROLLER_H_