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move tube oversampling to its own file

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This commit is contained in:
Connor Olding 2014-06-18 04:38:47 -07:00
parent eb2eec3709
commit 46a4d07e58
2 changed files with 38 additions and 31 deletions
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32
crap/tube.h
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@ -3,6 +3,7 @@
#include "util.h"
#include "param.h"
#include "os6iir.h"
#define ID 0x50F7BA11
#define LABEL "crap_tube"
@ -52,37 +53,6 @@ distort(double x)
return (27*x + 9) / (9*x*x + 6*x + 19) - 9/19.;
}
#define BQSHIFT(i) \
h[i*2 + 1] = h[i*2 + 0]; \
h[i*2 + 0] = x;
// b0 and b2 are equivalent and factored out
// b0 and a0 are factored out as overall gain
#define LOWPASS(i, b1, a1, a2) \
y = x + b1*h[i*2 + 0] + h[i*2 + 1] \
- a1*h[i*2 + 2] - a2*h[i*2 + 3]; \
BQSHIFT(i); \
x = y;
static double
oversample(double h[HIST_SIZE_2], double x)
{
/* Fp = 20000.62
os = 6; N = 8*2; Gp = 0.0135; Gs = 120;
*/
double y;
LOWPASS(0,-1.7310964991540,-1.7686201550064,+0.9924894080401);
LOWPASS(1,-1.7228987922703,-1.7591070571963,+0.9756664940293);
LOWPASS(2,-1.7030928294094,-1.7508784553758,+0.9530819894740);
LOWPASS(3,-1.6623628189757,-1.7420481292930,+0.9206849371458);
LOWPASS(4,-1.5767803723821,-1.7314029454409,+0.8755898544307);
LOWPASS(5,-1.3754954625889,-1.7189289035735,+0.8193999703446);
LOWPASS(6,-0.7934216412437,-1.7066722500921,+0.7627918423024);
LOWPASS(7,+1.1176227011686,-1.6987049565355,+0.7256338727337);
BQSHIFT(8);
return y*0.000005162322938;
}
static double
process_one(double x, double drive, double wet)
{

37
include/os6iir.h Normal file
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@ -0,0 +1,37 @@
/* IIR filter
Fp = 20000.62
os = 6; N = 8*2; Gp = 0.0135; Gs = 120;
overall delay: ~5 samples
*/
#define BQSHIFT(i) \
h[i*2 + 1] = h[i*2 + 0]; \
h[i*2 + 0] = x;
// b0 and b2 are equivalent and factored out
// b0 and a0 are factored out as overall gain
#define LOWPASS(i, b1, a1, a2) \
y = x + b1*h[i*2 + 0] + h[i*2 + 1] \
- a1*h[i*2 + 2] - a2*h[i*2 + 3]; \
BQSHIFT(i); \
x = y;
static double
oversample(double *h, double x)
{
// h[] should be at least 18 doubles long
double y;
LOWPASS(0,-1.7310964991540,-1.7686201550064,+0.9924894080401);
LOWPASS(1,-1.7228987922703,-1.7591070571963,+0.9756664940293);
LOWPASS(2,-1.7030928294094,-1.7508784553758,+0.9530819894740);
LOWPASS(3,-1.6623628189757,-1.7420481292930,+0.9206849371458);
LOWPASS(4,-1.5767803723821,-1.7314029454409,+0.8755898544307);
LOWPASS(5,-1.3754954625889,-1.7189289035735,+0.8193999703446);
LOWPASS(6,-0.7934216412437,-1.7066722500921,+0.7627918423024);
LOWPASS(7,+1.1176227011686,-1.6987049565355,+0.7256338727337);
BQSHIFT(8);
return y*0.000005162322938;
}
#undef BQSHIFT
#undef LOWPASS