reverb_node.h - mozsearch

Enable keyboard shortcuts

/*

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_GRAPH_REVERB_NODE_H_

#define RESONANCE_AUDIO_GRAPH_REVERB_NODE_H_

#include "api/resonance_audio_api.h"

#include "base/audio_buffer.h"

#include "dsp/fft_manager.h"

#include "dsp/reverb_onset_compensator.h"

#include "dsp/spectral_reverb.h"

#include "graph/system_settings.h"

#include "node/processing_node.h"

namespace vraudio {

// Implements a spectral reverb producing a decorrelated stereo output with

// onset compensated by a pair of convolution filters.

class ReverbNode : public ProcessingNode {

 public:

  // Constructs a |ReverbNode|.

//

  // @param system_settings Global system configuration.

  // @param fft_manager Pointer to a manager to perform FFT transformations.

  ReverbNode(const SystemSettings& system_settings, FftManager* fft_manager);

  // Updates the |SpectralReverb| using the current room properties or RT60

  // values depending on the system settings.

  void Update();

  const AudioBuffer *GetOutputBuffer() const;

 protected:

  // Implements ProcessingNode.

  const AudioBuffer* AudioProcess(const NodeInput& input) override;

 private:

  // Global system configuration.

  const SystemSettings& system_settings_;

  // Current reverb properties.

  ReverbProperties reverb_properties_;

  // New reverb properties.

  ReverbProperties new_reverb_properties_;

  // Per band reverb time update step sizes.

  std::vector<float> rt60_band_update_steps_;

  // Update step size for the gain parameter.

  float gain_update_step_;

  // Denotes whether the rt60s are currently being updated.

  bool rt60_updating_;

  // Denotes whether the gain is currently being updated.

  bool gain_updating_;

  // Number of buffers to updae rt60s over.

  float buffers_to_update_;

  // DSP class to perform filtering associated with the reverb.

  SpectralReverb spectral_reverb_;

  // DSP class to perform spectral reverb onset compensation.

  ReverbOnsetCompensator onset_compensator_;

  // Number of frames of zeroed out data to be processed by the node to ensure

  // the entire tail is rendered after input has ceased.

  size_t num_frames_processed_on_empty_input_;

  // Longest current reverb time, across all bands, in frames.

  size_t reverb_length_frames_;

  // Output buffers for mixing spectral reverb and compensator output.

  AudioBuffer output_buffer_;

  AudioBuffer compensator_output_buffer_;

  // Silence mono buffer to render reverb tails during the absence of input

  // buffers.

  AudioBuffer silence_mono_buffer_;

};

}  // namespace vraudio

#endif  // RESONANCE_AUDIO_GRAPH_REVERB_NODE_H_