57 lines
1.1 KiB
C
57 lines
1.1 KiB
C
#include "math.h"
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#ifdef __SSE2__
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#include <xmmintrin.h>
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#endif
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static void
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disable_denormals();
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#define LIMIT(v,l,u) ((v)<(l)?(l):((v)>(u)?(u):(v)))
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#define DB2LIN(x) ((x) > -90 ? pow(10, (x) * 0.05) : 0)
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/* frequency to rads/sec (angular frequency) */
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#define ANGULAR(fc, fs) (2 * M_PI / (fs) * (fc))
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#define ANGULAR_LIM(fc, fs) (2 * M_PI / (fs) * LIMIT((fc), 1, (fs)/2))
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typedef struct {
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double a1, a2, b0, b1, b2, x1, x2, y1, y2;
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} biquad;
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typedef struct {
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double b0, b1, b2, a0, a1, a2;
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} biquad_interim;
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static float
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whitenoise();
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static void
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biquad_init(biquad *bq);
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typedef enum {
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FILT_PEAKING,
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FILT_LOWSHELF,
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FILT_HIGHSHELF,
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FILT_LOWPASS,
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FILT_HIGHPASS,
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FILT_ALLPASS,
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FILT_BANDPASS,
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FILT_BANDPASS_2,
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FILT_NOTCH,
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FILT_GAIN
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} filter_t;
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static biquad
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biquad_gen(filter_t type, double fc, double gain, double bw, double fs);
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/* s-plane to z-plane */
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static biquad_interim
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design(double cw, double sw,
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double num0, double num1, double num2,
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double den0, double den1, double den2);
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static double
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biquad_run(biquad *bq, double x);
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#include "util_def.h"
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