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getting ready for next release

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This commit is contained in:
Mark Borgerding
2003-10-26 04:07:32 +00:00
parent 52b4b9ab5c
commit 1db3d91ee5
9 changed files with 68 additions and 314 deletions
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88
kiss_fft.c
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@ -23,13 +23,6 @@ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
typedef struct { kiss_fft_scalar r; kiss_fft_scalar i; }kiss_fft_cpx; */
#include "kiss_fft.h"
/* Try static inline. Who knows? You might get a speed improvement. I didn't. YMMV */
#if 0
# define FUNCDECL static inline
#else
# define FUNCDECL
#endif
typedef struct {
int nfft;
int inverse;
@ -47,25 +40,15 @@ typedef struct {
}while(0)
# define C_FIXDIV(c,div) \
do{ (c).r /= div; (c).i /=div; }while(0)
#define C_MUL_SCALAR(m,s) \
do{ (m).r = ( (m).r * (s) + (1<<14) ) >> 15;\
(m).i = ( (m).i * (s) + (1<<14) ) >> 15;\
}while(0)
#else /* not FIXED_POINT*/
#define C_MUL_SCALAR(m,s) \
do{ (m).r *= (s);\
(m).i *= (s);\
}while(0)
# define C_FIXDIV(c,div) /* NOOP */
#define C_MUL(m,a,b) \
do{ (m).r = (a).r*(b).r - (a).i*(b).i;\
(m).i = (a).r*(b).i + (a).i*(b).r; }while(0)
#endif
#define C_ADD( res, a,b)\
do { (res).r=(a).r+(b).r; (res).i=(a).i+(b).i; }while(0)
#define C_SUB( res, a,b)\
do { (res).r=(a).r-(b).r; (res).i=(a).i-(b).i; }while(0)
#define C_ADDTO( res , a)\
@ -93,7 +76,6 @@ kiss_fft_cpx cexp(double phase)
return x;
}
FUNCDECL
void bfly2(
kiss_fft_cpx * Fout,
int fstride,
@ -116,52 +98,6 @@ void bfly2(
}while (--m);
}
FUNCDECL
void bfly3(
kiss_fft_cpx * Fout,
int fstride,
const kiss_fft_state * st,
int m
)
{
kiss_fft_cpx *Fout0,*Fout1,*Fout2;
int u;
kiss_fft_cpx * scratch = st->scratch;
kiss_fft_cpx *tw1,*tw2;
tw2 = tw1 = st->twiddles;
Fout0=Fout;
Fout1=Fout0+m;
Fout2=Fout0+2*m;
scratch[3] = st->twiddles[ fstride*m ];
for ( u=0; u<m; ++u ) {
C_FIXDIV(*Fout0,3);
C_FIXDIV(*Fout1,3);
C_FIXDIV(*Fout2,3);
scratch[0] = *Fout0;
C_MUL(scratch[1],*Fout1 , *tw1 );
tw1 += fstride;
C_MUL(scratch[2],*Fout2 , *tw2 );
tw2 += 2*fstride;
C_ADD(scratch[5],scratch[1],scratch[2]);
C_SUB(scratch[6],scratch[1],scratch[2]);
C_ADDTO(*Fout0,scratch[5]);
C_MUL_SCALAR(scratch[5], scratch[3].r );
C_MUL_SCALAR(scratch[6], scratch[3].i );
scratch[4].r = scratch[5].r - scratch[6].i;
scratch[4].i = scratch[5].i + scratch[6].r;
C_ADD( *Fout1, scratch[0] , scratch[4] );
*Fout2 = *Fout1;
Fout2->r += 2*scratch[6].i;
Fout2->i -= 2*scratch[6].r;
++Fout0;++Fout1;++Fout2;
}
}
FUNCDECL
void bfly4(
kiss_fft_cpx * Fout,
int fstride,
@ -214,8 +150,7 @@ void bfly4(
}while(--m);
}
FUNCDECL
void bflyp(
void bfly_generic(
kiss_fft_cpx * Fout,
int fstride,
const kiss_fft_state * st,
@ -227,6 +162,7 @@ void bflyp(
kiss_fft_cpx * scratch = st->scratch;
kiss_fft_cpx * twiddles = st->twiddles;
kiss_fft_cpx t;
int Norig = st->nfft;
for ( u=0; u<m; ++u ) {
k=u;
@ -241,7 +177,6 @@ void bflyp(
int twidx=0;
Fout[ k ] = scratch[0];
for (q=1;q<p;++q ) {
int Norig = st->nfft;
twidx += fstride * k;
if (twidx>=Norig) twidx-=Norig;
C_MUL(t,scratch[q] , twiddles[twidx] );
@ -252,7 +187,6 @@ void bflyp(
}
}
FUNCDECL
void fft_work(
kiss_fft_cpx * Fout,
const kiss_fft_cpx * f,
@ -274,10 +208,9 @@ void fft_work(
}
switch (p) {
case 2: bfly2(Fout,fstride,st,m); break;
case 3: bfly3(Fout,fstride,st,m); break;
case 4: bfly4(Fout,fstride,st,m); break;
default: bflyp(Fout,fstride,st,m,p); break;
case 2: bfly2(Fout,fstride,st,m); break;
default: bfly_generic(Fout,fstride,st,m,p); break;
}
}
@ -324,7 +257,7 @@ void * kiss_fft_alloc(int nfft,int inverse_fft)
while (nfft>1) {
/* If you add a new radix, don't forget to put it here */
const int primes[] = {4,2,3,-1};
const int primes[] = {4,2,-1};
int p=nfft;
i=0;
while ( primes[i] != -1 ) {
@ -345,10 +278,13 @@ void * kiss_fft_alloc(int nfft,int inverse_fft)
void kiss_fft(const void * cfg,kiss_fft_cpx *f)
{
int n;
const kiss_fft_state * st = cfg;
n = st->nfft;
memcpy(st->tmpbuf,f,sizeof(kiss_fft_cpx)*n);
memcpy(st->tmpbuf,f,sizeof(kiss_fft_cpx)*st->nfft);
fft_work( f, st->tmpbuf, 1, st->factors,st );
}
void kiss_fft_io(const void * cfg,const kiss_fft_cpx *fin,kiss_fft_cpx *fout)
{
const kiss_fft_state * st = cfg;
fft_work( fout, fin, 1, st->factors,st );
}