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diff --git a/src/3rdparty/resonance-audio/resonance_audio/dsp/reverb_onset_compensator.h b/src/3rdparty/resonance-audio/resonance_audio/dsp/reverb_onset_compensator.h
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+/*
+Copyright 2018 Google Inc. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS-IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+#ifndef RESONANCE_AUDIO_DSP_REVERB_ONSET_COMPENSATOR_H_
+#define RESONANCE_AUDIO_DSP_REVERB_ONSET_COMPENSATOR_H_
+
+#include <list>
+#include <vector>
+
+#include "base/audio_buffer.h"
+#include "dsp/delay_filter.h"
+#include "dsp/fft_manager.h"
+#include "dsp/partitioned_fft_filter.h"
+#include "dsp/reverb_onset_update_processor.h"
+
+namespace vraudio {
+
+// Implements a convolutional compensator for the spectral reverb onset curve.
+class ReverbOnsetCompensator {
+ public:
+  // Constructs a |ReverbOnsetCompensator|.
+  //
+  // @param sampling_rate The sampling rate in Hz.
+  // @param frames_per_buffer The number of frames per buffer in the system.
+  // @param fft_manager Pointer to a FftManager to perform FFT transformations.
+  ReverbOnsetCompensator(int sampling_rate, size_t frames_per_buffer,
+                         FftManager* fft_manager);
+
+  // Resets the reverb with a new set of reverberation times. The new tail is
+  // generated by replacing the current tail buffer by buffer.
+  //
+  // @param rt60_values |kNumReverbOctaveBands| values denoting the
+  //     reverberation decay time to -60dB in octave bands starting at
+  //     |kLowestOctaveBand|.
+  // @param gain Gain to be applied across all frequencies.
+  void Update(const float* rt60_values, float gain);
+
+  // Processes a mono |AudioBuffer| with a reverberant tail.
+  //
+  // @param input A mono |AudioBuffer| of input data.
+  // @param output Pointer to stereo output buffer.
+  void Process(const AudioBuffer& input, AudioBuffer* output);
+
+ private:
+  // Generates the constituent curves which are combined to make up the
+  // correction curve envelopes. These envelopes ensure the initial part of the
+  // specral reverb's impulse response, which exhibits 'growing' behaviour,
+  // follows the desired exponential decay.
+  void GenerateCorrectionCurves();
+
+  // Generates a pair of |kNumOctaveBands| band, octave filtered, noise buffers.
+  void GenerateNoiseVectors();
+
+  // Manager for all FFT related functionality (not owned).
+  FftManager* const fft_manager_;
+
+  // The system sampling rate.
+  const int sampling_rate_;
+
+  // The system number of frames per buffer.
+  const size_t frames_per_buffer_;
+
+  // Pre-generated band-passed noise to be used as a base for the reverb tail.
+  std::vector<AudioBuffer> bandpassed_noise_left_;
+  std::vector<AudioBuffer> bandpassed_noise_right_;
+
+  // The constituent curves used to generate the onset compensation envelopes.
+  AudioBuffer base_curves_;
+  AudioBuffer adder_curves_;
+
+  // Filter for processing the left reverberant channel.
+  PartitionedFftFilter left_filter_;
+
+  // Filter for processing the right reverberant channel.
+  PartitionedFftFilter right_filter_;
+
+  // Delay filter used to ensure the compensation curve starts at the same point
+  // as the spectral reverb.
+  DelayFilter delay_filter_;
+
+  // Number of active update processors.
+  size_t num_active_processors_;
+
+  // Active reverb update processors to replace the corresponding filter
+  // partitions of the reverb tail within each process call.
+  std::list<std::unique_ptr<ReverbOnsetUpdateProcessor>> update_processors_;
+
+  // Temporary buffer used to process filter kernel partitions.
+  AudioBuffer temp_kernel_buffer_;
+
+  // Temporary buffer to hold FFT frequency domain output.
+  PartitionedFftFilter::FreqDomainBuffer temp_freq_buffer_;
+};
+
+}  // namespace vraudio
+
+#endif  // RESONANCE_AUDIO_DSP_REVERB_ONSET_COMPENSATOR_H_