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diff --git a/src/3rdparty/resonance-audio/resonance_audio/ambisonics/ambisonic_binaural_decoder.h b/src/3rdparty/resonance-audio/resonance_audio/ambisonics/ambisonic_binaural_decoder.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_AMBISONICS_AMBISONIC_BINAURAL_DECODER_H_
+#define RESONANCE_AUDIO_AMBISONICS_AMBISONIC_BINAURAL_DECODER_H_
+
+#include <vector>
+
+#include "base/audio_buffer.h"
+#include "dsp/fft_manager.h"
+#include "dsp/partitioned_fft_filter.h"
+
+namespace vraudio {
+
+// Decodes an Ambisonic sound field, of an arbitrary order, to binaural stereo,
+// by performing convolution in the spherical harmonics domain. The order (hence
+// the number of channels) of the input must match the order (hence the number
+// of channels) of the spherical harmonic-encoded Head Related Impulse Responses
+// (HRIRs). Assumes that HRIRs are symmetric with respect to the sagittal plane.
+class AmbisonicBinauralDecoder {
+ public:
+  // Constructs an |AmbisonicBinauralDecoder| from an |AudioBuffer| containing
+  // spherical harmonic representation of HRIRs. The order of spherical
+  // harmonic-encoded HRIRs (hence the number of channels) must match the order
+  // of the Ambisonic sound field input.
+  //
+  // @param sh_hrirs |AudioBuffer| containing time-domain spherical harmonic
+  //   encoded symmetric HRIRs.
+  // @param frames_per_buffer Number of frames in each input/output buffer.
+  // @param fft_manager Pointer to a manager to perform FFT transformations.
+  AmbisonicBinauralDecoder(const AudioBuffer& sh_hrirs,
+                           size_t frames_per_buffer, FftManager* fft_manager);
+
+  // Processes an Ambisonic sound field input and outputs a binaurally decoded
+  // stereo buffer.
+  //
+  // @param input Input buffer to be processed.
+  // @param output Pointer to a stereo output buffer.
+  void Process(const AudioBuffer& input, AudioBuffer* output);
+
+ private:
+  // Manager for all FFT related functionality (not owned).
+  FftManager* const fft_manager_;
+
+  // Spherical Harmonic HRIR filter kernels.
+  std::vector<std::unique_ptr<PartitionedFftFilter>> sh_hrir_filters_;
+
+  // Frequency domain representation of the input signal.
+  PartitionedFftFilter::FreqDomainBuffer freq_input_;
+
+  // Temporary audio buffer to store the convolution output for asymmetric or
+  // symmetric spherical harmonic HRIR.
+  AudioBuffer filtered_input_;
+};
+
+}  // namespace vraudio
+
+#endif  // RESONANCE_AUDIO_AMBISONICS_AMBISONIC_BINAURAL_DECODER_H_