filterbank.h

// Copyright (C) 2025 Alexandre St-Onge
// SPDX-License-Identifier: MIT
#pragma once
 
#include "audio_processor.h"
#include "filter.h"
 
#include <cstddef>
#include <cstdint>
#include <memory>
#include <vector>
 
namespace sfFDN
{
class FilterBank : public AudioProcessor
{
  public:
    FilterBank();
 
    void Clear() override;
 
    void AddFilter(std::unique_ptr<AudioProcessor> filter);
 
    void Process(const AudioBuffer& input, AudioBuffer& output) noexcept SFFDN_NONBLOCKING override;
 
    uint32_t InputChannelCount() const noexcept SFFDN_NONBLOCKING override;
 
    uint32_t OutputChannelCount() const noexcept SFFDN_NONBLOCKING override;
 
    std::unique_ptr<AudioProcessor> Clone() const override;
 
  private:
    std::vector<std::unique_ptr<AudioProcessor>> filters_;
};
 
class IIRFilterBank : public AudioProcessor
{
  public:
    IIRFilterBank();
 
    IIRFilterBank(const IIRFilterBank&) = delete;
    IIRFilterBank& operator=(const IIRFilterBank&) = delete;
 
    IIRFilterBank(IIRFilterBank&& other) noexcept;
    IIRFilterBank& operator=(IIRFilterBank&& other) noexcept;
 
    ~IIRFilterBank() override;
 
    void Clear() override;
 
    void SetFilter(std::span<const FilterCoefficients> coeffs, uint32_t channel_count);
 
    void Process(const AudioBuffer& input, AudioBuffer& output) noexcept SFFDN_NONBLOCKING override;
 
    uint32_t InputChannelCount() const noexcept SFFDN_NONBLOCKING override;
 
    uint32_t OutputChannelCount() const noexcept SFFDN_NONBLOCKING override;
 
    std::unique_ptr<AudioProcessor> Clone() const override;
 
  private:
    class IIRFilterBankImpl;
    std::unique_ptr<IIRFilterBankImpl> impl_;
 
    std::vector<FilterCoefficients> coeffs_;
};
 
} // namespace sfFDN