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fft0.c
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fft0.c
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// Copyright (c) <2012> <Leif Asbrink>
//
// Permission is hereby granted, free of charge, to any person
// obtaining a copy of this software and associated documentation
// files (the "Software"), to deal in the Software without restriction,
// including without limitation the rights to use, copy, modify,
// merge, publish, distribute, sublicense, and/or sell copies of
// the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
// WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
// OR OTHER DEALINGS IN THE SOFTWARE.
#include "globdef.h"
#include "uidef.h"
#include "fft1def.h"
#include "fft2def.h"
#define SQRTHALF 0.707106781186547524400844362104F
void fft_real_to_hermitian(float *z, int size, int n, COSIN_TABLE *tab)
{
// decimation-in-time, split-radix
int i, j;
int i1, i2, i3, i4, itab, itab3, inc, inc3;
float cc1, ss1, cc3, ss3;
register float t1, t2;
float t3, t4, t5, t6;
int mask, is, id,ik;
int n2, n4, n8, n5, n6;
int iz;
mask = size-1;
is = 0;
id = 4;
ik=8;
do
{
for (i=is; i<size; i+=ik)
{
t1 = z[i];
z[i ] += z[i+1];
z[i+1] = t1 - z[i+1];
t1 = z[i+id];
z[i+id ] += z[i+id+1];
z[i+id+1] = t1 - z[i+id+1];
}
is = (id<<1)-2;
id <<= 2;
ik<<=2;
} while (is<size/2);
t1=z[is];
z[is ]+=z[is+1];
z[is+1]=t1-z[is+1];
is=0;
id=8;
do
{
for (i=is; i<size; i+=id)
{
t1=z[i+3]+z[i+2];
z[i+3]-=z[i+2];
z[i+2]=z[i]-t1;
z[i]+=t1;
}
is=(id<<1)-4;
id<<=2;
} while (is<size);
n2=4;
for(iz=1; iz<n; iz++)
{
n5=n2;
n4=n2>>1;
n8=n2>>2;
n2<<=1;
n6=n4+n5;
is=0;
id=n2<<1;
do
{
for (i=is; i<size; i+=id)
{
i2=i+n4;
i3=i2+n4;
i4=i3+n4;
i1=i+n8;
t1=z[i4]+z[i3];
z[i4]-=z[i3];
z[i3]=z[i]-t1;
z[i]+=t1;
i3+=n8;
i4+=n8;
i2+=n8;
t1=(z[i3]+z[i4])*SQRTHALF;
t2=(z[i3]-z[i4])*SQRTHALF;
z[i4]=z[i2]-t1;
z[i3]=-z[i2]-t1;
z[i2]=z[i1]-t2;
z[i1]+=t2;
}
is=(id<<1)-n2;
id<<=2;
} while(is<size);
inc = size/n2;
itab = inc;
inc3=inc+(inc<<1);
itab3=inc3;
for (j=1; j<n8; j++)
{
cc1=tab[itab].cos;
ss1=tab[itab].sin;
cc3=tab[itab3].cos;
ss3=tab[itab3].sin;
is = 0;
id = n2<<1;
itab = (itab+inc)&(mask);
itab3 = (itab3+inc3)&(mask);
do
{
for (i=is; i<size; i+=id)
{
t1=z[i+j+n5]*cc1+z[i-j+n6]*ss1;
t3=z[i+j+n6]*cc3+z[i-j+n2]*ss3;
t2=z[i-j+n6]*cc1-z[i+j+n5]*ss1;
t4=z[i-j+n2]*cc3-z[i+j+n6]*ss3;
t5=t1+t3;
t3=t1-t3;
t6=t2+t4;
t4=t2-t4;
t2=z[i-j+n5]+t6;
z[i+j+n5]=t6-z[i-j+n5];
z[i-j+n2]=t2;
t2=z[i+j+n4]-t3;
z[i-j+n6]=-z[i+j+n4]-t3;
z[i+j+n6]=t2;
t1=z[i+j]+t5;
z[i-j+n5]=z[i+j]-t5;
z[i+j]=t1;
t1=z[i-j+n4]+t4;
z[i-j+n4]-=t4;
z[i+j+n4]=t1;
}
is = (id<<1) - n2;
id <<= 2;
} while (is<size);
}
}
}
void bulk_of_dif(int size, int n, float *x, COSIN_TABLE *sincos, int yieldflag)
{
int inc, j2, m2, m1, ja;
int ia, ib,it;
float x1,x2,t1,t2,t3,t4;
inc=2;
j2=size/2;
m2=size;
for(m1=1; m1<n-1; m1++)
{
if(yieldflag)lir_sched_yield();
for(ja=0; ja<=2*size-m2; ja+=m2)
{
it=0;
for(ia=ja; ia<j2+ja; ia+=2)
{
ib=ia+j2;
t1=x[ia];
t2=x[ib];
x[ia ]=t1+t2;
t3=x[ia+1];
t4=x[ib+1];
x1=t1-t2;
x[ia+1]=t3+t4;
x2=t3-t4;
x[ib ]=sincos[it].cos*x1-sincos[it].sin*x2;
x[ib+1]=sincos[it].sin*x1+sincos[it].cos*x2;
it+=inc;
}
}
inc*=2;
m2=m2/2;
j2=j2/2;
}
}
void bulk_of_dual_dif(int size, int n, float *x, COSIN_TABLE *sincos, int yieldflag)
{
int inc, j2, m2, m1, ja;
int ia, ib,it;
float x1,x2,t1,t2,t3,t4;
inc=2;
j2=size/2;
m2=size;
for(m1=1; m1<n-1; m1++)
{
if(yieldflag)lir_sched_yield();
for(ja=0; ja<=2*size-m2; ja+=m2)
{
it=0;
for(ia=ja; ia<j2+ja; ia+=2)
{
ib=ia+j2;
t1=x[2*ia];
t2=x[2*ib];
x[2*ia ]=t1+t2;
t3=x[2*ia+1];
t4=x[2*ib+1];
x1=t1-t2;
x[2*ia+1]=t3+t4;
x2=t3-t4;
x[2*ib ]=sincos[it].cos*x1-sincos[it].sin*x2;
x[2*ib+1]=sincos[it].sin*x1+sincos[it].cos*x2;
t1=x[2*ia+2];
t2=x[2*ib+2];
x[2*ia+2]=t1+t2;
t3=x[2*ia+3];
t4=x[2*ib+3];
x1=t1-t2;
x[2*ia+3]=t3+t4;
x2=t3-t4;
x[2*ib+2]=sincos[it].cos*x1-sincos[it].sin*x2;
x[2*ib+3]=sincos[it].sin*x1+sincos[it].cos*x2;
it+=inc;
}
}
inc*=2;
m2=m2/2;
j2=j2/2;
}
}
void fft_iqshift(int size, float *x)
{
int i,k;
float t1;
for(i=0; i<size/2; i++)
{
k=i+size/2;
t1=x[2*i];
x[2*i]=x[2*k];
x[2*k]=t1;
t1=x[2*i+1];
x[2*i+1]=x[2*k+1];
x[2*k+1]=t1;
}
}
void dual_fftback(int size,
int n, float *x,
COSIN_TABLE *sincos,
unsigned short int *permute,
int yieldflag)
{
int inc, j2, m2, m1, ja;
int ia, ib,it;
float x1,x2,t1,t2,t3,t4;
inc=1;
j2=size;
m2=2*size;
for(m1=0; m1<n; m1++)
{
if(yieldflag)lir_sched_yield();
for(ja=0; ja<=2*size-m2; ja+=m2)
{
it=0;
for(ia=ja; ia<j2+ja; ia+=2)
{
ib=ia+j2;
t1=x[2*ia];
t2=x[2*ib];
x[2*ia ]=t1+t2;
t3=x[2*ia+1];
t4=x[2*ib+1];
x1=t1-t2;
x[2*ia+1]=t3+t4;
x2=t3-t4;
x[2*ib ]= sincos[it].cos*x1+sincos[it].sin*x2;
x[2*ib+1]=-sincos[it].sin*x1+sincos[it].cos*x2;
t1=x[2*ia+2];
t2=x[2*ib+2];
x[2*ia+2]=t1+t2;
t3=x[2*ia+3];
t4=x[2*ib+3];
x1=t1-t2;
x[2*ia+3]=t3+t4;
x2=t3-t4;
x[2*ib+2]= sincos[it].cos*x1+sincos[it].sin*x2;
x[2*ib+3]=-sincos[it].sin*x1+sincos[it].cos*x2;
it+=inc;
}
}
inc*=2;
m2=m2/2;
j2=j2/2;
}
if(yieldflag)lir_sched_yield();
for(ia=0; ia < size; ia++)
{
ib=permute[ia ];
if(ib<ia)
{
t1=x[4*ia];
x[4*ia]=x[4*ib];
x[4*ib]=t1;
t1=x[4*ia+1];
x[4*ia+1]=x[4*ib+1];
x[4*ib+1]=t1;
t1=x[4*ia+2];
x[4*ia+2]=x[4*ib+2];
x[4*ib+2]=t1;
t1=x[4*ia+3];
x[4*ia+3]=x[4*ib+3];
x[4*ib+3]=t1;
}
}
}
void fftback(int size,
int n, float *x,
COSIN_TABLE *sincos,
unsigned short int *permute,
int yieldflag)
{
int inc, j2, m2, m1, ja;
int ia, ib,it;
float x1,x2,t1,t2,t3,t4;
inc=1;
j2=size;
m2=2*size;
for(m1=0; m1<n; m1++)
{
if(yieldflag)lir_sched_yield();
for(ja=0; ja<=2*size-m2; ja+=m2)
{
it=0;
for(ia=ja; ia<j2+ja; ia+=2)
{
ib=ia+j2;
t1=x[ia];
t2=x[ib];
x[ia ]=t1+t2;
t3=x[ia+1];
t4=x[ib+1];
x1=t1-t2;
x[ia+1]=t3+t4;
x2=t3-t4;
x[ib ]= sincos[it].cos*x1+sincos[it].sin*x2;
x[ib+1]=-sincos[it].sin*x1+sincos[it].cos*x2;
it+=inc;
}
}
inc*=2;
m2=m2/2;
j2=j2/2;
}
if(yieldflag)lir_sched_yield();
for(ia=0; ia < size; ia++)
{
ib=permute[ia ];
if(ib<ia)
{
t1=x[2*ia];
x[2*ia]=x[2*ib];
x[2*ib]=t1;
t1=x[2*ia+1];
x[2*ia+1]=x[2*ib+1];
x[2*ib+1]=t1;
}
}
}
void d_fftback(int size,
int n, double *x,
D_COSIN_TABLE *sincos,
unsigned short int *permute)
{
int inc, j2, m2, m1, ja;
int ia, ib,it;
double x1,x2,t1,t2,t3,t4;
inc=1;
j2=size;
m2=2*size;
for(m1=0; m1<n; m1++)
{
for(ja=0; ja<=2*size-m2; ja+=m2)
{
it=0;
for(ia=ja; ia<j2+ja; ia+=2)
{
ib=ia+j2;
t1=x[ia];
t2=x[ib];
x[ia ]=t1+t2;
t3=x[ia+1];
t4=x[ib+1];
x1=t1-t2;
x[ia+1]=t3+t4;
x2=t3-t4;
x[ib ]= sincos[it].cos*x1+sincos[it].sin*x2;
x[ib+1]=-sincos[it].sin*x1+sincos[it].cos*x2;
it+=inc;
}
}
inc*=2;
m2=m2/2;
j2=j2/2;
}
for(ia=0; ia < size; ia++)
{
ib=permute[ia ];
if(ib<ia)
{
t1=x[2*ia];
x[2*ia]=x[2*ib];
x[2*ib]=t1;
t1=x[2*ia+1];
x[2*ia+1]=x[2*ib+1];
x[2*ib+1]=t1;
}
}
}
void fftforward(int size,
int n, float *x,
COSIN_TABLE *sincos,
unsigned short int *permute,
int yieldflag)
{
int inc, j2, m2, m1, ja;
int ia, ib,it;
float x1,x2,t1,t2,t3,t4;
inc=1;
j2=size;
m2=2*size;
for(m1=0; m1<n; m1++)
{
if(yieldflag)lir_sched_yield();
for(ja=0; ja<=2*size-m2; ja+=m2)
{
it=0;
for(ia=ja; ia<j2+ja; ia+=2)
{
ib=ia+j2;
t1=x[ia];
t2=x[ib];
x[ia ]=t1+t2;
t3=x[ia+1];
t4=x[ib+1];
x1=t1-t2;
x[ia+1]=t3+t4;
x2=t3-t4;
x[ib ]= sincos[it].cos*x1-sincos[it].sin*x2;
x[ib+1]= sincos[it].sin*x1+sincos[it].cos*x2;
it+=inc;
}
}
inc*=2;
m2=m2/2;
j2=j2/2;
}
if(yieldflag)lir_sched_yield();
for(ia=0; ia < size; ia++)
{
ib=permute[ia ];
if(ib<ia)
{
t1=x[2*ia];
x[2*ia]=x[2*ib];
x[2*ib]=t1;
t1=x[2*ia+1];
x[2*ia+1]=x[2*ib+1];
x[2*ib+1]=t1;
}
}
}
void d_fftforward(int size,
int n, double *x,
D_COSIN_TABLE *sincos,
unsigned short int *permute)
{
int inc, j2, m2, m1, ja;
int ia, ib,it;
double x1,x2,t1,t2,t3,t4;
inc=1;
j2=size;
m2=2*size;
for(m1=0; m1<n; m1++)
{
for(ja=0; ja<=2*size-m2; ja+=m2)
{
it=0;
for(ia=ja; ia<j2+ja; ia+=2)
{
ib=ia+j2;
t1=x[ia];
t2=x[ib];
x[ia ]=t1+t2;
t3=x[ia+1];
t4=x[ib+1];
x1=t1-t2;
x[ia+1]=t3+t4;
x2=t3-t4;
x[ib ]= sincos[it].cos*x1-sincos[it].sin*x2;
x[ib+1]= sincos[it].sin*x1+sincos[it].cos*x2;
it+=inc;
}
}
inc*=2;
m2=m2/2;
j2=j2/2;
}
for(ia=0; ia < size; ia++)
{
ib=permute[ia ];
if(ib<ia)
{
t1=x[2*ia];
x[2*ia]=x[2*ib];
x[2*ib]=t1;
t1=x[2*ia+1];
x[2*ia+1]=x[2*ib+1];
x[2*ib+1]=t1;
}
}
for(ia=0; ia < 2*size; ia++)
{
x[ia]/=size;
}
}
void big_fftforward(int size,
int n, float *x,
COSIN_TABLE *sincos,
unsigned int *permute,
int yieldflag)
{
// This routine is only called from THREAD_FFT2 and that is the thread
// that we should give priority in a dual core machine.
// Allow it to run 100 % of the time if there is more than one CPU.
int inc, j2, m2, m1, ja;
int ia, ib,it;
float x1,x2,t1,t2,t3,t4;
inc=1;
j2=size;
m2=2*size;
for(m1=0; m1<n; m1++)
{
if(yieldflag)lir_sched_yield();
for(ja=0; ja<=2*size-m2; ja+=m2)
{
it=0;
for(ia=ja; ia<j2+ja; ia+=2)
{
ib=ia+j2;
t1=x[ia];
t2=x[ib];
x[ia ]=t1+t2;
t3=x[ia+1];
t4=x[ib+1];
x1=t1-t2;
x[ia+1]=t3+t4;
x2=t3-t4;
x[ib ]= sincos[it].cos*x1-sincos[it].sin*x2;
x[ib+1]= sincos[it].sin*x1+sincos[it].cos*x2;
it+=inc;
}
}
inc*=2;
m2=m2/2;
j2=j2/2;
}
if(yieldflag)lir_sched_yield();
for(ia=0; ia < size; ia++)
{
ib=(int)permute[ia ];
if(ib<ia)
{
t1=x[2*ia];
x[2*ia]=x[2*ib];
x[2*ib]=t1;
t1=x[2*ia+1];
x[2*ia+1]=x[2*ib+1];
x[2*ib+1]=t1;
}
}
}
extern int *baseband_handle;
void make_window(int mo, int sz, int n, float *win)
{
double x,z,sumsq;
double e1, e2;
float t1;
int i, size;
if(mo == 5 || mo == 6)
{
e1=3.2;
e2=13.0/sz;
for (i=0; i <= sz/2; i++)
{
win[i]=0.5F*(float)erfc(e1);
e1-=e2;
}
if(mo == 5)return;
for (i=0; i < sz/2; i++)
{
win[i]=(float)pow(win[i]+.0005,-2.0);
win[sz-i-1]=win[i];
}
return;
}
if(n == 0)return;
size=sz;
z=n;
if(mo == 2)size=2*sz;
sumsq=0;
// Produce a sin power n function over size/2 points for n=1 to 7.
// In case n equals 9, use the error function erfc instead, start at -150 dB.
if(n==9)
{
e1=3.6;
e2=80.0/size;
if(size < 128)e2/=1.5;
if(size < 64)e2/=1.7;
for (i=0; i <= size/2; i++)
{
win[i]=0.5F*(float)erfc(e1);
sumsq+=win[i]*win[i];
e1-=e2;
}
}
else
{
// In case n equals 8, use a Gaussian.
if(n==8)
{
e1=0;
e2=8.4/size;
for (i=size/2; i > 0; i--)
{
win[i]=(float)pow(2.7,-e1*e1);
sumsq+=win[i]*win[i];
e1+=e2;
}
}
else
{
x=0;
for (i=0; i <= size/2; i++)
{
win[i]=(float)pow(sin(x),z);
sumsq+=win[i]*win[i];
x+=PI_L/size;
}
}
}
if(mo == 5)return;
// Produce an inverted window over size/2 points
if(mo == 3)
{
win[0]=1;
for (i=1; i <= size/2; i++)
{
win[i]=1/win[i];
}
return;
}
z=1/sqrt(2*sumsq/size);
for (i=0; i <= size/2; i++)
{
win[i]*=(float)z;
}
if(mo == 4)
{
for(i=size/2+1; i<size; i++)
{
win[i]=win[size-i];
}
return;
}
// Store the data in the order we want to use it
// This will save time by better cash usage for large transforms.
if(mo == 1)
{
t1=win[1];
win[1]=win[size/2];
for (i=size/2-1; i >1; i--)
{
win[2*i]=win[i];
}
win[2]=t1;
for (i=0; i < size-3; i+=2)
{
win[i+3]=win[size-i-2];
}
}
}
void make_mmxwindow(int mo, int size, int n, short int *win)
{
double x,z,t1;
int i, k, iw;
double *tmpwin;
double e1, e2;
if(n <= 0)return;
// We only use MMX when the second fft is enabled.
tmpwin=(double*)timf2_shi;
// Produce a sin power n function over size points for n=1 to 7.
// In case n equals 9, use the error function erfc instead, start at -150 dB.
if(n==9)
{
e1=3.6;
e2=80.0/size;
if(size < 128)e2/=1.5;
if(size < 64)e2/=1.7;
for (i=0; i <= size/2; i++)
{
tmpwin[i]=0.5*erfc(e1);
e1-=e2;
}
}
else
{
// In case n equals 8, use a Gaussian.
if(n==8)
{
e1=0;
e2=8.4/size;
for (i=size/2; i > 0; i--)
{
tmpwin[i]=pow(2.7,-e1*e1);
e1+=e2;
}
}
else
{
x=0;
z=n;
for (i=0; i <= size/2; i++)
{
tmpwin[i]=pow(sin(x),z);
x+=PI_L/size;
}
}
}
for(i=size-1; i>size/2; i--)
{
tmpwin[i]=tmpwin[size-i];
}
// ************************************************
// mo == 0
// Produce a sin power n function over size points
// Store each value once.
x=0;
z=n;
if(mo == 0)
{
for (i=0; i < size; i++)
{
t1=tmpwin[i];
iw=(int)((0.5+0x8000)*t1);
if(iw >= 0x8000)iw=0x7fff;
win[i]=(short int)iw;
x+=PI_L/size;
}
return;
}
// Produce a sin power n function over size/2 points
// or the inverted function over size/2+1 points
// Store the result 4 times for dual or quad transforms
k=size/2;
if(mo==3)k++;
for (i=0; i < k; i++)
{
t1=tmpwin[i];
x+=PI_L/size;
if(mo == 3)t1=0.5/t1;
t1=floor(0x7f00*t1);
iw=(int)t1;
if(iw>0x7ffe)iw=0x7ffe;
win[4*i ]=(short int)iw;
win[4*i+1]=(short int)iw;
win[4*i+2]=(short int)iw;
win[4*i+3]=(short int)iw;
}
}
void init_mmxfft( int size, MMX_COSIN_TABLE *tab)
{
double x;
int i,is,ic;
x=0;
for (i=0; i<size/2; i++)
{
is=(int)(32767.5*sin(x));
ic=(int)(32767.5*cos(x));
if(is>0x7fff)is=0x7fff;
if(ic>0x7fff)ic=0x7fff;
if(is<-0x7fff)is=-0x7fff;
if(ic<-0x7fff)ic=-0x7fff;
x+=(double)(PI_L/(size/2));
tab[i].c1p=(short int)ic;
tab[i].s2p=(short int)is;
tab[i].c3p=(short int)-is;
tab[i].s4m=(short int)ic;
}
}
void make_permute(int mo, int nz, int sz, unsigned short int *perm)
{
unsigned int i, i2, j, k, l, m;
unsigned short int *tmp;
unsigned int n, size;
if(mo == 2)
{
n=(unsigned int)(nz+1);
size=(unsigned int)(sz*2);
}
else
{
n=(unsigned int)nz;
size=(unsigned int)sz;
}
if(size > 65536)
{
lirerr(937);
return;
}
for(i=0; i<size; i++)perm[i]=0;
tmp=malloc(size*sizeof(short int));
if(tmp == NULL)
{
lirerr(1032);
return;
}
for(i=0; i<size; i++)tmp[i]=(short unsigned int)i;
for(i=1; i<size; i++)
{
m=i;
j=0;
for(k=0; k<n; k++)
{
j=2*j;
l=m/2;
if(2*l != m)j=j+1;
m=l;
}
if(j > i)
{
i2=tmp[i];
tmp[i]=tmp[j];
tmp[j]=(short unsigned int)i2;
}
}
if(mo == 1)
{
for(i=0; i<size/2; i++)
{
k=tmp[i];
tmp[i]=tmp[i+size/2];
tmp[i+size/2]=(short unsigned int)k;
}
}
for(i=0; i<size; i++)perm[tmp[i]]=(short unsigned int)i;
free(tmp);
}
void make_bigpermute(int mo, int nz, int sz, unsigned int *perm)
{
unsigned int i, i2, j, k, l, m;
unsigned int *tmp;
unsigned int n, size;
if(mo == 2)
{
n=(unsigned int)nz+1;
size=(unsigned int)sz*2;
}
else
{
n=(unsigned int)nz;
size=(unsigned int)sz;
}
for(i=0; i<size; i++)perm[i]=0;
tmp=malloc(size*sizeof(int));
if(tmp == NULL)
{
lirerr(1032);
return;
}
for(i=0; i<size; i++)tmp[i]=i;
for(i=0; i<size; i++)
{
m=i;
j=0;
for(k=0; k<n; k++)
{
j=2*j;
l=m/2;
if(2*l != m)j=j+1;
m=l;
}
if(j > i)
{
i2=tmp[i];
tmp[i]=tmp[j];
tmp[j]=i2;
}
}
if(mo == 1)
{
for(i=0; i<size/2; i++)
{
k=tmp[i];
tmp[i]=tmp[i+size/2];
tmp[i+size/2]=k;
}
}
for(i=0; i<size; i++)perm[tmp[i]]=i;
free(tmp);
}
void make_sincos(int mo, int sz, COSIN_TABLE *tab)
{
int i;
double x,step;
int size;
if(mo == 2)
{
size=sz*2;
}
else
{
size=sz;
}
x=0;
step=(double)(PI_L/(size/2));
for (i=0; i<size/2; i++)
{
tab[i].sin=(float)sin(x);
tab[i].cos=(float)cos(x);
x+=step;
}
}
void make_d_sincos(int mo, int sz, D_COSIN_TABLE *tab)
{
int i;
double x,step;
int size;
if(mo == 2)
{
size=sz*2;
}
else
{
size=sz;
}
x=0;
step=(double)(PI_L/(size/2));
for (i=0; i<size/2; i++)
{
tab[i].sin=sin(x);
tab[i].cos=cos(x);
x+=step;
}
}
void init_fft(int mo, int nz, int sz, COSIN_TABLE *tab,
unsigned short int *perm)
{
make_permute(mo, nz, sz, perm);
make_sincos(mo, sz, tab);
}
void init_d_fft(int mo, int nz, int sz, D_COSIN_TABLE *tab,
unsigned short int *perm)
{
make_permute(mo, nz, sz, perm);
make_d_sincos(mo, sz, tab);
}