Line data    Source code

       1              : #pragma once
       2              : 
       3              : // 3-band parametric equalizer for tone correction and pedal-chain shaping.
       4              : // The Equalizer cascades active biquads H(z)=H_lowShelf(z)*H_peakMid(z)*H_highShelf(z),
       5              : // giving independent low-shelf, peaking-mid, and high-shelf gain control.
       6              : 
       7              : #include "audio/effects/effect.h"
       8              : #include "audio/dsp/biquad.h"
       9              : 
      10              : namespace Amplitron {
      11              : 
      12            3 : class Equalizer : public Effect {
      13              : public:
      14              :     Equalizer();
      15              :     void process(float* buffer, int num_samples) override;
      16              :     void set_sample_rate(int sample_rate) override;
      17              :     void reset() override;
      18          125 :     const char* name() const override { return "Equalizer"; }
      19            3 :     const char* type_id() const override { return "Equalizer"; }
      20          170 :     std::vector<EffectParam>& params() override { return params_; }
      21              : 
      22              : private:
      23              :     std::vector<EffectParam> params_;
      24              : 
      25              :     Biquad low_shelf_;
      26              :     Biquad mid_peak_;
      27              :     Biquad high_shelf_;
      28              : 
      29              :     // One-pole smoothing states (avoids zipper noise on UI parameter jumps)
      30              :     float bass_state_ = 0.0f;
      31              :     float mid_state_ = 0.0f;
      32              :     float treble_state_ = 0.0f;
      33              :     float presence_state_ = 0.0f;
      34              : 
      35              :     // Cached parameter values for dirty-check
      36              :     float cached_bass_ = -999.0f;
      37              :     float cached_mid_ = -999.0f;
      38              :     float cached_treble_ = -999.0f;
      39              :     float cached_presence_ = -999.0f;
      40              : 
      41              :     void recompute_coefficients_if_dirty();
      42              : };
      43              : 
      44              : } // namespace Amplitron