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@ -3,69 +3,207 @@ |
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#include <Arduino.h> |
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#include <Audio.h> |
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#define EQ_LOWPASS 0 |
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#define EQ_HIGHPASS 1 |
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#define EQ_BANDPASS 2 |
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#define EQ_NOTCH 3 |
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#define EQ_PEAK 4 |
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#define EQ_LOWSHELF 5 |
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#define EQ_HIGHSHELF 6 |
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#define GRAPHIC_EQ_TYPE_0 EQ_HIGHPASS |
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#define GRAPHIC_EQ_CENTER_FRQ_0 115.0 |
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#define GRAPHIC_EQ_Q_0 2.0 |
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#define GRAPHIC_EQ_TYPE_1 EQ_BANDPASS |
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#define GRAPHIC_EQ_CENTER_FRQ_1 330.0 |
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#define GRAPHIC_EQ_Q_1 2.0 |
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#define GRAPHIC_EQ_TYPE_2 EQ_BANDPASS |
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#define GRAPHIC_EQ_CENTER_FRQ_2 990.0 |
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#define GRAPHIC_EQ_Q_2 2.0 |
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#define GRAPHIC_EQ_TYPE_3 EQ_BANDPASS |
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#define GRAPHIC_EQ_CENTER_FRQ_3 2000.0 |
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#define GRAPHIC_EQ_Q_3 2.0 |
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#define GRAPHIC_EQ_TYPE_4 EQ_BANDPASS |
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#define GRAPHIC_EQ_CENTER_FRQ_4 4000.0 |
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#define GRAPHIC_EQ_Q_4 2.0 |
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#define GRAPHIC_EQ_TYPE_5 EQ_BANDPASS |
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#define GRAPHIC_EQ_CENTER_FRQ_5 9900.0 |
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#define GRAPHIC_EQ_Q_5 2.0 |
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#define GRAPHIC_EQ_TYPE_6 EQ_LOWPASS |
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#define GRAPHIC_EQ_CENTER_FRQ_6 11000.0 |
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#define GRAPHIC_EQ_Q_6 2.0 |
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extern AudioControlSGTL5000 sgtl5000_1; |
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typedef struct biquad_coefficients_s { |
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float32_t a0; |
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float32_t a1; |
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float32_t a2; |
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float32_t b1; |
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float32_t b2; |
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} biquad_coefficients_t; |
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typedef struct biquad_params_s { |
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uint8_t filter_type; |
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float32_t Fc; |
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float32_t Q; |
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} biquad_params_t; |
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enum { |
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bq_type_lowpass = 0, |
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bq_type_highpass, |
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bq_type_bandpass, |
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bq_type_notch, |
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bq_type_peak, |
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bq_type_lowshelf, |
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bq_type_highshelf |
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class BiquadCoef |
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{ |
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public: |
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BiquadCoef(uint8_t num_bands); |
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~BiquadCoef(); |
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void set_eq_type(uint8_t band, uint8_t ft); |
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void set_eq_Fc(uint8_t band, float32_t frq); |
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void set_eq_Q(uint8_t band, float32_t q); |
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void set_gain(uint8_t band, float32_t gain); |
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void get_coef(uint8_t band, int* c); |
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private: |
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void calcBiquadCoefficients(uint8_t band); |
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uint8_t num_bands; |
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uint8_t *filter_type; |
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float32_t *Fc; |
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float32_t *Q; |
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float32_t *peakGainDB; |
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float32_t *a0; |
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float32_t *a1; |
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float32_t *a2; |
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float32_t *b1; |
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float32_t *b2; |
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}; |
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#define NUM_GRAPHIC_EQ_BANDS 7 |
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BiquadCoef::BiquadCoef(uint8_t num_bands) |
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{ |
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num_bands = constrain(num_bands, 1, 7); |
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sgtl5000_1.eqFilterCount(num_bands); |
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filter_type = new uint8_t[num_bands]; |
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Fc = new float32_t[num_bands]; |
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Q = new float32_t[num_bands]; |
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peakGainDB = new float32_t[num_bands]; |
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a0 = new float32_t[num_bands]; |
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a1 = new float32_t[num_bands]; |
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a2 = new float32_t[num_bands]; |
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b1 = new float32_t[num_bands]; |
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b2 = new float32_t[num_bands]; |
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biquad_coefficients_t biquad_coefficients[NUM_GRAPHIC_EQ_BANDS]; |
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biquad_params_t biquad_params[NUM_GRAPHIC_EQ_BANDS]; |
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set_eq_type(0, GRAPHIC_EQ_TYPE_0); |
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set_eq_Fc(0, GRAPHIC_EQ_CENTER_FRQ_0); |
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set_eq_Q(0, GRAPHIC_EQ_Q_0); |
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set_gain(0, 0.0); |
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void set_sgtl5000_7band_eq(uint8_t band, uint8_t filter_type, float32_t Fc, float32_t Q); |
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void set_sgtl5000_7band_eq_gain(uint8_t band, float32_t peakGainDB); |
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void setup_sgtl5000_graphic_7band_eq(void); |
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void calcBiquadCoefficients(biquad_coefficients_t* biquad_coefficients, uint8_t filter_type, float32_t Fc, float32_t Q, float32_t peakGain); |
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if (num_bands > 1) |
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{ |
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set_eq_type(1, GRAPHIC_EQ_TYPE_1); |
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set_eq_Fc(1, GRAPHIC_EQ_CENTER_FRQ_1); |
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set_eq_Q(1, GRAPHIC_EQ_Q_1); |
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set_gain(1, 0.0); |
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} |
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void set_sgtl5000_7band_eq(uint8_t band, uint8_t filter_type, float32_t Fc, float32_t Q) |
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if (num_bands > 2) |
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{ |
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set_eq_type(2, GRAPHIC_EQ_TYPE_2); |
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set_eq_Fc(2, GRAPHIC_EQ_CENTER_FRQ_2); |
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set_eq_Q(2, GRAPHIC_EQ_Q_2); |
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set_gain(2, 0.0); |
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} |
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if (num_bands > 3) |
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{ |
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set_eq_type(3, GRAPHIC_EQ_TYPE_3); |
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set_eq_Fc(3, GRAPHIC_EQ_CENTER_FRQ_3); |
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set_eq_Q(3, GRAPHIC_EQ_Q_3); |
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set_gain(3, 0.0); |
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} |
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if (num_bands > 4) |
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{ |
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set_eq_type(4, GRAPHIC_EQ_TYPE_4); |
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set_eq_Fc(4, GRAPHIC_EQ_CENTER_FRQ_4); |
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set_eq_Q(4, GRAPHIC_EQ_Q_4); |
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set_gain(4, 0.0); |
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} |
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if (num_bands > 5) |
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{ |
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set_eq_type(5, GRAPHIC_EQ_TYPE_5); |
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set_eq_Fc(5, GRAPHIC_EQ_CENTER_FRQ_5); |
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set_eq_Q(5, GRAPHIC_EQ_Q_5); |
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set_gain(5, 0.0); |
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} |
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if (num_bands > 6) |
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{ |
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set_eq_type(6, GRAPHIC_EQ_TYPE_6); |
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set_eq_Fc(6, GRAPHIC_EQ_CENTER_FRQ_6); |
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set_eq_Q(6, GRAPHIC_EQ_Q_6); |
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set_gain(6, 0.0); |
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} |
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for (uint8_t i = 0; i < num_bands; i++) |
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{ |
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int tmp[num_bands]; |
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calcBiquadCoefficients(i); |
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get_coef(i, tmp); |
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sgtl5000_1.eqFilter(i, tmp); |
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} |
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} |
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BiquadCoef::~BiquadCoef() |
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{ |
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; |
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} |
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void BiquadCoef::set_eq_type(uint8_t band, uint8_t ft) |
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{ |
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biquad_params[band].filter_type = filter_type; |
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biquad_params[band].Fc = Fc; |
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biquad_params[band].Q = Q; |
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int tmp[num_bands]; |
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filter_type[band] = ft; |
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calcBiquadCoefficients(band); |
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get_coef(band, tmp); |
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sgtl5000_1.eqFilter(band, tmp); |
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} |
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calcBiquadCoefficients(&biquad_coefficients[band], filter_type, Fc, Q, 0.0); |
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void BiquadCoef::set_eq_Fc(uint8_t band, float32_t frq) |
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{ |
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int tmp[num_bands]; |
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//sgtl5000_1.eqFilter(band, biquad_coefficients);
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Fc[band] = frq; |
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calcBiquadCoefficients(band); |
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get_coef(band, tmp); |
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sgtl5000_1.eqFilter(band, tmp); |
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} |
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void set_sgtl5000_7band_eq_gain(uint8_t band, float32_t peakGainDB) |
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void BiquadCoef::set_eq_Q(uint8_t band, float32_t q) |
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{ |
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calcBiquadCoefficients(&biquad_coefficients[band], biquad_params[band].filter_type, biquad_params[band].Fc, biquad_params[band].Q, peakGainDB); |
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//sgtl5000_1.eqFilter(band, biquad_coefficients);
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int tmp[num_bands]; |
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Q[band] = q; |
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calcBiquadCoefficients(band); |
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get_coef(band, tmp); |
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sgtl5000_1.eqFilter(band, tmp); |
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} |
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void setup_sgtl5000_graphic_7band_eq(void) |
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void BiquadCoef::set_gain(uint8_t band, float32_t gain) |
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{ |
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//sgtl5000_1.eqFilterCount(7); // enable 7 bands
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set_sgtl5000_7band_eq(0, GRAPHIC_EQ_TYPE_0, GRAPHIC_EQ_CENTER_FRQ_0, GRAPHIC_EQ_Q_0); |
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set_sgtl5000_7band_eq(1, GRAPHIC_EQ_TYPE_1, GRAPHIC_EQ_CENTER_FRQ_1, GRAPHIC_EQ_Q_1); |
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set_sgtl5000_7band_eq(2, GRAPHIC_EQ_TYPE_2, GRAPHIC_EQ_CENTER_FRQ_2, GRAPHIC_EQ_Q_2); |
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set_sgtl5000_7band_eq(3, GRAPHIC_EQ_TYPE_3, GRAPHIC_EQ_CENTER_FRQ_3, GRAPHIC_EQ_Q_3); |
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set_sgtl5000_7band_eq(4, GRAPHIC_EQ_TYPE_4, GRAPHIC_EQ_CENTER_FRQ_4, GRAPHIC_EQ_Q_4); |
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set_sgtl5000_7band_eq(5, GRAPHIC_EQ_TYPE_5, GRAPHIC_EQ_CENTER_FRQ_5, GRAPHIC_EQ_Q_5); |
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set_sgtl5000_7band_eq(6, GRAPHIC_EQ_TYPE_6, GRAPHIC_EQ_CENTER_FRQ_6, GRAPHIC_EQ_Q_6); |
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int tmp[num_bands]; |
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peakGainDB[band] = gain; |
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calcBiquadCoefficients(band); |
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get_coef(band, tmp); |
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sgtl5000_1.eqFilter(band, tmp); |
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} |
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void BiquadCoef::get_coef(uint8_t band, int* c) |
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{ |
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if (c != NULL) |
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{ |
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c[0] = a0[band] * 0x8000; |
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c[1] = a1[band] * 0x8000; |
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c[2] = a2[band] * 0x8000; |
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c[3] = b1[band] * 0x8000; |
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c[4] = b2[band] * 0x8000; |
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} |
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} |
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// Taken from https://www.earlevel.com/main/2012/11/26/biquad-c-source-code/
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@ -86,100 +224,103 @@ void setup_sgtl5000_graphic_7band_eq(void) |
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// You may modify and use this source code to create binary code
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// for your own purposes, free or commercial.
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//
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void calcBiquadCoefficients(biquad_coefficients_t* biquad_coefficients, uint8_t filter_type, float32_t Fc, float32_t Q, float32_t peakGain) |
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void BiquadCoef::calcBiquadCoefficients(uint8_t band) |
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{ |
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if (band > num_bands) |
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band = num_bands; |
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float32_t norm; |
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float32_t V = pow(10, fabs(peakGain) / 20.0); |
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float32_t K = tan(M_PI * Fc); |
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switch (filter_type) { |
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case bq_type_lowpass: |
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norm = 1 / (1 + K / Q + K * K); |
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biquad_coefficients->a0 = K * K * norm; |
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biquad_coefficients->a1 = 2 * biquad_coefficients->a0; |
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biquad_coefficients->a2 = biquad_coefficients->a0; |
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biquad_coefficients->b1 = 2 * (K * K - 1) * norm; |
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biquad_coefficients->b2 = (1 - K / Q + K * K) * norm; |
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float32_t V = pow(10, fabs(peakGainDB[band]) / 20.0); |
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float32_t K = tan(M_PI * Fc[band]); |
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switch (filter_type[band]) { |
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case EQ_LOWPASS: |
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norm = 1 / (1 + K / Q[band] + K * K); |
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a0[band] = K * K * norm; |
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a1[band] = 2 * a0[band]; |
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a2[band] = a0[band]; |
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b1[band] = 2 * (K * K - 1) * norm; |
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b2[band] = (1 - K / Q[band] + K * K) * norm; |
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break; |
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case bq_type_highpass: |
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norm = 1 / (1 + K / Q + K * K); |
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biquad_coefficients->a0 = 1 * norm; |
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biquad_coefficients->a1 = -2 * biquad_coefficients->a0; |
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biquad_coefficients->a2 = biquad_coefficients->a0; |
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biquad_coefficients->b1 = 2 * (K * K - 1) * norm; |
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biquad_coefficients->b2 = (1 - K / Q + K * K) * norm; |
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case EQ_HIGHPASS: |
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norm = 1 / (1 + K / Q[band] + K * K); |
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a0[band] = 1 * norm; |
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a1[band] = -2 * a0[band]; |
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a2[band] = a0[band]; |
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b1[band] = 2 * (K * K - 1) * norm; |
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b2[band] = (1 - K / Q[band] + K * K) * norm; |
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break; |
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case bq_type_bandpass: |
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norm = 1 / (1 + K / Q + K * K); |
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biquad_coefficients->a0 = K / Q * norm; |
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biquad_coefficients->a1 = 0; |
|
|
|
|
biquad_coefficients->a2 = -biquad_coefficients->a0; |
|
|
|
|
biquad_coefficients->b1 = 2 * (K * K - 1) * norm; |
|
|
|
|
biquad_coefficients->b2 = (1 - K / Q + K * K) * norm; |
|
|
|
|
case EQ_BANDPASS: |
|
|
|
|
norm = 1 / (1 + K / Q[band] + K * K); |
|
|
|
|
a0[band] = K / Q[band] * norm; |
|
|
|
|
a1[band] = 0; |
|
|
|
|
a2[band] = -a0[band]; |
|
|
|
|
b1[band] = 2 * (K * K - 1) * norm; |
|
|
|
|
b2[band] = (1 - K / Q[band] + K * K) * norm; |
|
|
|
|
break; |
|
|
|
|
|
|
|
|
|
case bq_type_notch: |
|
|
|
|
norm = 1 / (1 + K / Q + K * K); |
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|
|
|
biquad_coefficients->a0 = (1 + K * K) * norm; |
|
|
|
|
biquad_coefficients->a1 = 2 * (K * K - 1) * norm; |
|
|
|
|
biquad_coefficients->a2 = biquad_coefficients->a0; |
|
|
|
|
biquad_coefficients->b1 = biquad_coefficients->a1; |
|
|
|
|
biquad_coefficients->b2 = (1 - K / Q + K * K) * norm; |
|
|
|
|
case EQ_NOTCH: |
|
|
|
|
norm = 1 / (1 + K / Q[band] + K * K); |
|
|
|
|
a0[band] = (1 + K * K) * norm; |
|
|
|
|
a1[band] = 2 * (K * K - 1) * norm; |
|
|
|
|
a2[band] = a0[band]; |
|
|
|
|
b1[band] = a1[band]; |
|
|
|
|
b2[band] = (1 - K / Q[band] + K * K) * norm; |
|
|
|
|
break; |
|
|
|
|
|
|
|
|
|
case bq_type_peak: |
|
|
|
|
if (peakGain >= 0) { // boost
|
|
|
|
|
norm = 1 / (1 + 1 / Q * K + K * K); |
|
|
|
|
biquad_coefficients->a0 = (1 + V / Q * K + K * K) * norm; |
|
|
|
|
biquad_coefficients->a1 = 2 * (K * K - 1) * norm; |
|
|
|
|
biquad_coefficients->a2 = (1 - V / Q * K + K * K) * norm; |
|
|
|
|
biquad_coefficients->b1 = biquad_coefficients->a1; |
|
|
|
|
biquad_coefficients->b2 = (1 - 1 / Q * K + K * K) * norm; |
|
|
|
|
case EQ_PEAK: |
|
|
|
|
if (peakGainDB[band] >= 0) { // boost
|
|
|
|
|
norm = 1 / (1 + 1 / Q[band] * K + K * K); |
|
|
|
|
a0[band] = (1 + V / Q[band] * K + K * K) * norm; |
|
|
|
|
a1[band] = 2 * (K * K - 1) * norm; |
|
|
|
|
a2[band] = (1 - V / Q[band] * K + K * K) * norm; |
|
|
|
|
b1[band] = a1[band]; |
|
|
|
|
b2[band] = (1 - 1 / Q[band] * K + K * K) * norm; |
|
|
|
|
} |
|
|
|
|
else { // cut
|
|
|
|
|
norm = 1 / (1 + V / Q * K + K * K); |
|
|
|
|
biquad_coefficients->a0 = (1 + 1 / Q * K + K * K) * norm; |
|
|
|
|
biquad_coefficients->a1 = 2 * (K * K - 1) * norm; |
|
|
|
|
biquad_coefficients->a2 = (1 - 1 / Q * K + K * K) * norm; |
|
|
|
|
biquad_coefficients->b1 = biquad_coefficients->a1; |
|
|
|
|
biquad_coefficients->b2 = (1 - V / Q * K + K * K) * norm; |
|
|
|
|
norm = 1 / (1 + V / Q[band] * K + K * K); |
|
|
|
|
a0[band] = (1 + 1 / Q[band] * K + K * K) * norm; |
|
|
|
|
a1[band] = 2 * (K * K - 1) * norm; |
|
|
|
|
a2[band] = (1 - 1 / Q[band] * K + K * K) * norm; |
|
|
|
|
b1[band] = a1[band]; |
|
|
|
|
b2[band] = (1 - V / Q[band] * K + K * K) * norm; |
|
|
|
|
} |
|
|
|
|
break; |
|
|
|
|
case bq_type_lowshelf: |
|
|
|
|
if (peakGain >= 0) { // boost
|
|
|
|
|
case EQ_LOWSHELF: |
|
|
|
|
if (peakGainDB[band] >= 0) { // boost
|
|
|
|
|
norm = 1 / (1 + sqrt(2) * K + K * K); |
|
|
|
|
biquad_coefficients->a0 = (1 + sqrt(2 * V) * K + V * K * K) * norm; |
|
|
|
|
biquad_coefficients->a1 = 2 * (V * K * K - 1) * norm; |
|
|
|
|
biquad_coefficients->a2 = (1 - sqrt(2 * V) * K + V * K * K) * norm; |
|
|
|
|
biquad_coefficients->b1 = 2 * (K * K - 1) * norm; |
|
|
|
|
biquad_coefficients->b2 = (1 - sqrt(2) * K + K * K) * norm; |
|
|
|
|
a0[band] = (1 + sqrt(2 * V) * K + V * K * K) * norm; |
|
|
|
|
a1[band] = 2 * (V * K * K - 1) * norm; |
|
|
|
|
a2[band] = (1 - sqrt(2 * V) * K + V * K * K) * norm; |
|
|
|
|
b1[band] = 2 * (K * K - 1) * norm; |
|
|
|
|
b2[band] = (1 - sqrt(2) * K + K * K) * norm; |
|
|
|
|
} |
|
|
|
|
else { // cut
|
|
|
|
|
norm = 1 / (1 + sqrt(2 * V) * K + V * K * K); |
|
|
|
|
biquad_coefficients->a0 = (1 + sqrt(2) * K + K * K) * norm; |
|
|
|
|
biquad_coefficients->a1 = 2 * (K * K - 1) * norm; |
|
|
|
|
biquad_coefficients->a2 = (1 - sqrt(2) * K + K * K) * norm; |
|
|
|
|
biquad_coefficients->b1 = 2 * (V * K * K - 1) * norm; |
|
|
|
|
biquad_coefficients->b2 = (1 - sqrt(2 * V) * K + V * K * K) * norm; |
|
|
|
|
a0[band] = (1 + sqrt(2) * K + K * K) * norm; |
|
|
|
|
a1[band] = 2 * (K * K - 1) * norm; |
|
|
|
|
a2[band] = (1 - sqrt(2) * K + K * K) * norm; |
|
|
|
|
b1[band] = 2 * (V * K * K - 1) * norm; |
|
|
|
|
b2[band] = (1 - sqrt(2 * V) * K + V * K * K) * norm; |
|
|
|
|
} |
|
|
|
|
break; |
|
|
|
|
case bq_type_highshelf: |
|
|
|
|
if (peakGain >= 0) { // boost
|
|
|
|
|
case EQ_HIGHSHELF: |
|
|
|
|
if (peakGainDB[band] >= 0) { // boost
|
|
|
|
|
norm = 1 / (1 + sqrt(2) * K + K * K); |
|
|
|
|
biquad_coefficients->a0 = (V + sqrt(2 * V) * K + K * K) * norm; |
|
|
|
|
biquad_coefficients->a1 = 2 * (K * K - V) * norm; |
|
|
|
|
biquad_coefficients->a2 = (V - sqrt(2 * V) * K + K * K) * norm; |
|
|
|
|
biquad_coefficients->b1 = 2 * (K * K - 1) * norm; |
|
|
|
|
biquad_coefficients->b2 = (1 - sqrt(2) * K + K * K) * norm; |
|
|
|
|
a0[band] = (V + sqrt(2 * V) * K + K * K) * norm; |
|
|
|
|
a1[band] = 2 * (K * K - V) * norm; |
|
|
|
|
a2[band] = (V - sqrt(2 * V) * K + K * K) * norm; |
|
|
|
|
b1[band] = 2 * (K * K - 1) * norm; |
|
|
|
|
b2[band] = (1 - sqrt(2) * K + K * K) * norm; |
|
|
|
|
} |
|
|
|
|
else { // cut
|
|
|
|
|
norm = 1 / (V + sqrt(2 * V) * K + K * K); |
|
|
|
|
biquad_coefficients->a0 = (1 + sqrt(2) * K + K * K) * norm; |
|
|
|
|
biquad_coefficients->a1 = 2 * (K * K - 1) * norm; |
|
|
|
|
biquad_coefficients->a2 = (1 - sqrt(2) * K + K * K) * norm; |
|
|
|
|
biquad_coefficients->b1 = 2 * (K * K - V) * norm; |
|
|
|
|
biquad_coefficients->b2 = (V - sqrt(2 * V) * K + K * K) * norm; |
|
|
|
|
a0[band] = (1 + sqrt(2) * K + K * K) * norm; |
|
|
|
|
a1[band] = 2 * (K * K - 1) * norm; |
|
|
|
|
a2[band] = (1 - sqrt(2) * K + K * K) * norm; |
|
|
|
|
b1[band] = 2 * (K * K - V) * norm; |
|
|
|
|
b2[band] = (V - sqrt(2 * V) * K + K * K) * norm; |
|
|
|
|
} |
|
|
|
|
break; |
|
|
|
|
} |
|
|
|
|