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diff --git a/chromium/third_party/webrtc/modules/audio_coding/neteq/background_noise.h b/chromium/third_party/webrtc/modules/audio_coding/neteq/background_noise.h
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+++ b/chromium/third_party/webrtc/modules/audio_coding/neteq/background_noise.h
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+/*
+ *  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.
+ */
+
+#ifndef WEBRTC_MODULES_AUDIO_CODING_NETEQ_BACKGROUND_NOISE_H_
+#define WEBRTC_MODULES_AUDIO_CODING_NETEQ_BACKGROUND_NOISE_H_
+
+#include <string.h>  // size_t
+
+#include "webrtc/base/constructormagic.h"
+#include "webrtc/modules/audio_coding/neteq/audio_multi_vector.h"
+#include "webrtc/modules/audio_coding/neteq/interface/neteq.h"
+#include "webrtc/system_wrappers/interface/scoped_ptr.h"
+#include "webrtc/typedefs.h"
+
+namespace webrtc {
+
+// Forward declarations.
+class PostDecodeVad;
+
+// This class handles estimation of background noise parameters.
+class BackgroundNoise {
+ public:
+  // TODO(hlundin): For 48 kHz support, increase kMaxLpcOrder to 10.
+  // Will work anyway, but probably sound a little worse.
+  static const int kMaxLpcOrder = 8;  // 32000 / 8000 + 4.
+
+  explicit BackgroundNoise(size_t num_channels);
+  virtual ~BackgroundNoise();
+
+  void Reset();
+
+  // Updates the parameter estimates based on the signal currently in the
+  // |sync_buffer|, and on the latest decision in |vad| if it is running.
+  void Update(const AudioMultiVector& sync_buffer,
+              const PostDecodeVad& vad);
+
+  // Returns |energy_| for |channel|.
+  int32_t Energy(size_t channel) const;
+
+  // Sets the value of |mute_factor_| for |channel| to |value|.
+  void SetMuteFactor(size_t channel, int16_t value);
+
+  // Returns |mute_factor_| for |channel|.
+  int16_t MuteFactor(size_t channel) const;
+
+  // Returns a pointer to |filter_| for |channel|.
+  const int16_t* Filter(size_t channel) const;
+
+  // Returns a pointer to |filter_state_| for |channel|.
+  const int16_t* FilterState(size_t channel) const;
+
+  // Copies |length| elements from |input| to the filter state. Will not copy
+  // more than |kMaxLpcOrder| elements.
+  void SetFilterState(size_t channel, const int16_t* input, size_t length);
+
+  // Returns |scale_| for |channel|.
+  int16_t Scale(size_t channel) const;
+
+  // Returns |scale_shift_| for |channel|.
+  int16_t ScaleShift(size_t channel) const;
+
+  // Accessors.
+  bool initialized() const { return initialized_; }
+  NetEqBackgroundNoiseMode mode() const { return mode_; }
+
+  // Sets the mode of the background noise playout for cases when there is long
+  // duration of packet loss.
+  void set_mode(NetEqBackgroundNoiseMode mode) { mode_ = mode; }
+
+ private:
+  static const int kThresholdIncrement = 229;  // 0.0035 in Q16.
+  static const int kVecLen = 256;
+  static const int kLogVecLen = 8;  // log2(kVecLen).
+  static const int kResidualLength = 64;
+  static const int kLogResidualLength = 6;  // log2(kResidualLength)
+
+  struct ChannelParameters {
+    // Constructor.
+    ChannelParameters() {
+      Reset();
+    }
+
+    void Reset() {
+      energy = 2500;
+      max_energy = 0;
+      energy_update_threshold = 500000;
+      low_energy_update_threshold = 0;
+      memset(filter_state, 0, sizeof(filter_state));
+      memset(filter, 0, sizeof(filter));
+      filter[0] = 4096;
+      mute_factor = 0,
+      scale = 20000;
+      scale_shift = 24;
+    }
+
+    int32_t energy;
+    int32_t max_energy;
+    int32_t energy_update_threshold;
+    int32_t low_energy_update_threshold;
+    int16_t filter_state[kMaxLpcOrder];
+    int16_t filter[kMaxLpcOrder + 1];
+    int16_t mute_factor;
+    int16_t scale;
+    int16_t scale_shift;
+  };
+
+  int32_t CalculateAutoCorrelation(const int16_t* signal,
+                                   int length,
+                                   int32_t* auto_correlation) const;
+
+  // Increments the energy threshold by a factor 1 + |kThresholdIncrement|.
+  void IncrementEnergyThreshold(size_t channel, int32_t sample_energy);
+
+  // Updates the filter parameters.
+  void SaveParameters(size_t channel,
+                      const int16_t* lpc_coefficients,
+                      const int16_t* filter_state,
+                      int32_t sample_energy,
+                      int32_t residual_energy);
+
+  size_t num_channels_;
+  scoped_ptr<ChannelParameters[]> channel_parameters_;
+  bool initialized_;
+  NetEqBackgroundNoiseMode mode_;
+
+  DISALLOW_COPY_AND_ASSIGN(BackgroundNoise);
+};
+
+}  // namespace webrtc
+#endif  // WEBRTC_MODULES_AUDIO_CODING_NETEQ_BACKGROUND_NOISE_H_