winamp/Src/Winamp/eq10dsp.cpp

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2024-09-24 12:54:57 +00:00
/*****************************************
EQ10 library version 1.0
Copyright (C)2002 4Front Technologies
Written by George Yohng
http://www.opensound.com
Proprietary software.
*****************************************/
#include "main.h"
#include "eq10dsp.h"
//#include <stdio.h>
//#include <string.h>
#include <math.h>
#include "WinampAttributes.h"
#define DENORMAL_FIX // comment this for no denormal fixes
char _eq10_copyright[]=
"EQ10 Library version 1.0\n"
"Copyright (C)2002 4Front Technologies http://www.opensound.com\n"
"Copyright (C)2001-2002 by George Yohng http://www.yohng.com\n\0"
"EQ10 ENGINE";
static double eq10_freq[EQ10_NOFBANDS]={ 70, 180, 320, 600, 1000, 3000, 6000, 12000, 14000, 16000 }; // winamp style frequency table;
static double eq10_freq_iso[EQ10_NOFBANDS]={31,62,125,250,500,1000,2000,4000,8000,16000}; // ISO frequency table
#ifdef EQ10_DQ
static double eq10_q[EQ10_NOFBANDS]=EQ10_DQ;
#endif
static void eq10_bsetup2(int u,double rate,eq10band_t *band,double freq,double Q)
{
double angle;
double a0,/*a1,a2,*/b0,b1,b2,alpha;
if (rate<4000.0) rate=4000.0;
if (rate>384000.0) rate=384000.0;
if (freq<20.0) freq=20.0;
if (freq>=(rate*0.499)) {band->ua0=band->da0=0;return;}
angle = 2.0*3.1415926535897932384626433832795*freq/rate;
alpha = sin(angle)/(2.0*Q);
b0 = 1.0/(1.0+alpha);
a0 = b0*alpha;
b1 = b0*2*cos(angle);
b2 = b0*(alpha-1);
if (u>0)
{
band->ua0=a0;
band->ub1=b1;
band->ub2=b2;
}
else
{
band->da0=a0;
band->db1=b1;
band->db2=b2;
}
}
static void eq10_bsetup(double rate,eq10band_t *band,double freq,double Q)
{
memset(band,0,sizeof(*band));
eq10_bsetup2(-1,rate,band,freq,Q*0.5);
eq10_bsetup2(1,rate,band,freq,Q*2.0);
#ifdef EQ10_DETECTOR_CODE
/* release of detector */
band->detectdecay=pow(0.001,1.0/(rate*EQ10_DETECTOR_RELEASE));
#endif
}
void eq10_setup(eq10_t *eq, int eqs, double rate)
{
int t,k;
for(k=0;k<eqs;k++,eq++)
{
for(t=0;t<EQ10_NOFBANDS;t++)
#ifndef EQ10_DQ
eq10_bsetup(rate,&eq->band[t],(config_eq_frequencies==EQ_FREQUENCIES_WINAMP)?eq10_freq[t]:eq10_freq_iso[t],EQ10_Q);
#else
eq10_bsetup(rate,&eq->band[t],(config_eq_frequencies==EQ_FREQUENCIES_WINAMP)?eq10_freq[t]:eq10_freq_iso[t],eq10_q[t]);
#endif
eq->detect=0;
/* release of trimmer */
eq->detectdecay=pow(0.001,1.0/(rate*EQ10_TRIM_RELEASE));
}
}
void eq10_processf(eq10_t *eq,float *buf,float *outbuf,int sz,int idx,int step)
{
int t,k;
float *in,*out;
if (!eq) return;
buf+=idx;
outbuf+=idx;
in=buf;
for(k=0;k<EQ10_NOFBANDS;k++)
{
double a0,b1,b2;
double x1 = eq->band[k].x1;
double x2 = eq->band[k].x2;
double y1 = eq->band[k].y1;
double y2 = eq->band[k].y2;
double gain = eq->band[k].gain;
#ifdef EQ10_DETECTOR_CODE
double detect = eq->band[k].detect;
double detectdecay = eq->band[k].detectdecay;
#endif
out = outbuf;
if (gain>0.0)
{
a0 = eq->band[k].ua0*gain;
b1 = eq->band[k].ub1;
b2 = eq->band[k].ub2;
}
else
{
a0 = eq->band[k].da0*gain;
b1 = eq->band[k].db1;
b2 = eq->band[k].db2;
}
if (a0==0.0) continue;
for(t=0;t<sz;t++,in+=step,out+=step)
{
double y0 = (in[0]-x2)*a0 + y1*b1 + y2*b2
#ifdef DENORMAL_FIX
+ 1e-30;
#else
;
#endif
#ifdef EQ10_DETECTOR_CODE
if (fabs(y0)>detect) detect=fabs(y0);
detect*=detectdecay;
#ifdef DENORMAL_FIX
detect+=1e-30;
#endif
#endif
x2=x1; x1=in[0]; y2=y1; y1=y0;
out[0] = (float)(y0 + in[0]);
}
in=outbuf;
eq->band[k].x1=x1;
eq->band[k].x2=x2;
eq->band[k].y1=y1;
eq->band[k].y2=y2;
#ifdef EQ10_DETECTOR_CODE
eq->band[k].detect=detect;
#endif
}
if (config_eq_limiter)
{
double detect=eq->detect;
double detectdecay=eq->detectdecay;
out=outbuf;
for(t=0;t<sz;t++,in+=step,out+=step)
{
/* *0.99 - reserve */
if (fabs(in[0])>detect) detect=fabs(in[0]);
if (detect>EQ10_TRIM_CODE)
out[0]=in[0]*(float)(EQ10_TRIM_CODE/detect);
else
out[0]=in[0];
detect*=detectdecay;
#ifdef DENORMAL_FIX
detect+=1e-30;
#endif
}
eq->detect=detect;
}
else if ((in==buf)&&(buf!=outbuf))
{
out=outbuf;
for(t=0;t<sz;t++,in+=step,out+=step) out[0]=in[0];
}
}
double eq10_db2gain(double gain_dB)
{
return pow(10.0,gain_dB/20.0)-1.0;
}
double eq10_gain2db(double gain)
{
return 20.0*log10(gain+1.0);
}
void eq10_setgain(eq10_t *eq,int eqs,int bandnr,double gain_dB)
{
double realgain;
int k;
if (!eq)
return;
realgain=eq10_db2gain(gain_dB);
for(k=0;k<eqs;k++,eq++)
eq->band[bandnr].gain=realgain;
}
double eq10_getgain(eq10_t *eq,int bandnr)
{
return eq10_gain2db(eq->band[bandnr].gain);
}
double eq10_detect(eq10_t *eq,int bandnr)
{
#ifdef EQ10_DETECTOR_CODE
return eq10_gain2db(eq->band[bandnr].detect);
#else
return 0;
#endif
}
#ifdef TESTCASE
eq10_t eq;
float buf1[4096] = {0};
float buf[4096] = {0};
int main()
{
int t,k;
eq10_setup(&eq,1,44100);
for(t=0;t<4096;t++)
{
buf1[t]=warand()*(1.0/16384);
}
for(t=0;t<EQ10_NOFBANDS;t++) eq.band[t].gain=-0.874107;
for(t=0;t<10000;t++)
{
eq10_processf(&eq,buf1,buf,4096,0,1);
}
return 0;
}
#endif