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diff --git a/src/3rdparty/resonance-audio/resonance_audio/dsp/partitioned_fft_filter.h b/src/3rdparty/resonance-audio/resonance_audio/dsp/partitioned_fft_filter.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_PARTITIONED_FFT_FILTER_H_
+#define RESONANCE_AUDIO_DSP_PARTITIONED_FFT_FILTER_H_
+
+#include <vector>
+
+#include "base/audio_buffer.h"
+#include "base/misc_math.h"
+#include "dsp/fft_manager.h"
+
+struct PFFFT_Setup;
+
+namespace vraudio {
+
+// Class performing a FFT-based overlap and add FIR convolution.
+// Given an FFT size N and a filter size M > N/2; the filter is broken in to
+// floor(M/(N/2)) partitions in the time domain. This results in a set of
+// frequency domain "filters" of length (N/2)+1.
+class PartitionedFftFilter {
+ public:
+  // Typedef declares the data type for storing frequency domain buffers. Each
+  // channel stores the kernel for a partition.
+  typedef AudioBuffer FreqDomainBuffer;
+
+  // Constructor preallocates memory based on the |filter_size|. This can be
+  // used for simplicity if the filter size will be constant after creation.
+  //
+  // @param filter_size Length of the time domain filter in samples. This will
+  //     be increased such that it becomes a multiple of |chunk_size_|.
+  // @param frames_per_buffer Number of points in each time domain input buffer.
+  // @param fft_manager Pointer to a manager to perform FFT transformations.
+  PartitionedFftFilter(size_t filter_size, size_t frames_per_buffer,
+                       FftManager* fft_manager);
+
+  // Constructor preallocates memory based on the |max_filter_size|. The
+  // |fft_size_| will be twice |frames_per_buffer| if this is a power of two and
+  // twice the next larger power of two if it is not.
+  //
+  // @param filter_size Length of the time domain filter in samples. This will
+  //     be increased such that it becomes a multiple of |chunk_size_|.
+  // @param frames_per_buffer Number of points in each time domain input buffer.
+  // @param max_filter_size Maximum length that |filter_size| can get.
+  // @param fft_manager Pointer to a manager for all fft related functionality.
+  PartitionedFftFilter(size_t filter_size, size_t frames_per_buffer,
+                       size_t max_filter_size, FftManager* fft_manager);
+
+  // Initializes the FIR filter from a time domain kernel.
+  //
+  // @parem kernel Time domain filter to be used for processing.
+  void SetTimeDomainKernel(const AudioBuffer::Channel& kernel);
+
+  // Initializes the FIR filter from a precomputed frequency domain kernel.
+  //
+  // @param kernel Frequency domain filter to be used for processing.
+  void SetFreqDomainKernel(const FreqDomainBuffer& kernel);
+
+  // Replaces a partition indicated by the |partition_index| with
+  // |kernel_chunk|'s frequency domain equivalent.
+  //
+  // @param partition_index Location (partition) of the time domain filter we
+  //     wish to replace.
+  // @param kernel_chunk |fft_size_|/2 length chunk of a filter used to
+  //     replace the |partition_index|th partition.
+  void ReplacePartition(size_t partition_index,
+                        const AudioBuffer::Channel& kernel_chunk);
+
+  // Alters the filter length by adding or removing partitions in the frequency
+  // domain. If |new_filter_size| is not a multiple of |chunk_size_| (i.e.
+  // frames per buffer), then the time domain filter kernel will be zeropadded
+  // to a multiple of |chunk_size_|.
+  //
+  // @param new_filter_size New length of the time domain filter kernel.
+  void SetFilterLength(size_t new_filter_size);
+
+  // Processes a block of frequency domain samples. The size of the input
+  // block must be |fft_size_|.
+  //
+  // @param Frequency domain input buffer.
+  void Filter(const FreqDomainBuffer::Channel& input);
+
+  // Returns block of filtered signal output of size |fft_size_|/2.
+  //
+  // @param output Time domain block filtered with the given kernel.
+  void GetFilteredSignal(AudioBuffer::Channel* output);
+
+  // Resets the filter state.
+  void Clear();
+
+ private:
+  friend class PartitionedFftFilterFrequencyBufferTest;
+
+  // Adjusts the |num_partitions_| and the size of |freq_domain_buffers_| for
+  // use with a new time domain filter kernel greater in length than the
+  // previous kernel.
+  //
+  // @param new_kernel_size Length of the time domain filter kernel.
+  void ResetFreqDomainBuffers(size_t new_kernel_size);
+
+  // Manager for all FFT related functionality (not owned).
+  FftManager* const fft_manager_;
+
+  // Number of points in the |fft_manager_|s FFT.
+  const size_t fft_size_;
+
+  // Size of each partition of the filter in time domain.
+  const size_t chunk_size_;
+
+  // Number of frames in each buffer of input data.
+  const size_t frames_per_buffer_;
+
+  // Maximum filter size in samples.
+  const size_t max_filter_size_;
+
+  // Maximum partition count.
+  const size_t max_num_partitions_;
+
+  // Filter size in samples.
+  size_t filter_size_;
+
+  // Partition Count.
+  size_t num_partitions_;
+
+  // Kernel buffer in frequency domain.
+  FreqDomainBuffer kernel_freq_domain_buffer_;
+
+  // Buffer selector to switch between two filtered signal buffers.
+  size_t buffer_selector_;
+
+  // The freq_domain_buffer we will write new incoming audio into.
+  size_t curr_front_buffer_;
+
+  // Frequency domain buffer used to perform filtering.
+  FreqDomainBuffer freq_domain_buffer_;
+
+  // Two buffers that are consecutively filled with filtered signal output.
+  AudioBuffer filtered_time_domain_buffers_;
+
+  // Accumulator for the outputs from each convolution partition
+  FreqDomainBuffer freq_domain_accumulator_;
+
+  // Temporary time domain buffer to store output when zero padding has been
+  // applied due to non power of two input buffer lengths.
+  AudioBuffer temp_zeropad_buffer_;
+
+  // Temporary time domain buffer to hold time domain kernel chunks during
+  // conversion of a kernel from time to frequency domain.
+  AudioBuffer temp_kernel_chunk_buffer_;
+};
+
+}  // namespace vraudio
+
+#endif  // RESONANCE_AUDIO_DSP_PARTITIONED_FFT_FILTER_H_