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#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "kiss_fftr.h"
#include "_kiss_fft_guts.h"
#include <stdio.h>
#include <string.h>
#include "../libcelt/kiss_fft.c"
#include "../libcelt/kiss_fftr.c"
int ret=0;
static
kiss_fft_scalar rand_scalar(void)
{
return (rand()%32767)-16384;
}
static
double snr_compare( kiss_fft_cpx * vec1,kiss_fft_scalar * vec2, int n)
{
int k;
double sigpow=1e-10, noisepow=1e-10, err,snr;
vec1[0].i = vec1[n].r;
for (k=0;k<n;++k) {
sigpow += (double)vec1[k].r * (double)vec1[k].r +
(double)vec1[k].i * (double)vec1[k].i;
err = (double)vec1[k].r - (double)vec2[2*k];
/*printf ("%f %f\n", (double)vec1[k].r, (double)vec2[2*k]);*/
noisepow += err * err;
err = (double)vec1[k].i - (double)vec2[2*k+1];
/*printf ("%f %f\n", (double)vec1[k].i, (double)vec2[2*k+1]);*/
noisepow += err * err;
}
snr = 10*log10( sigpow / noisepow );
if (snr<60) {
printf( "** poor snr: %f **\n", snr);
ret = 1;
}
return snr;
}
static
double snr_compare_scal( kiss_fft_scalar * vec1,kiss_fft_scalar * vec2, int n)
{
int k;
double sigpow=1e-10, noisepow=1e-10, err,snr;
for (k=0;k<n;++k) {
sigpow += (double)vec1[k] * (double)vec1[k];
err = (double)vec1[k] - (double)vec2[k];
noisepow += err * err;
}
snr = 10*log10( sigpow / noisepow );
if (snr<60) {
printf( "\npoor snr: %f\n", snr);
ret = 1;
}
return snr;
}
#ifdef RADIX_TWO_ONLY
#define NFFT 1024
#else
#define NFFT 8*3*5
#endif
#ifndef NUMFFTS
#define NUMFFTS 10000
#endif
int main(void)
{
int i;
kiss_fft_cpx cin[NFFT];
kiss_fft_cpx cout[NFFT];
kiss_fft_scalar fin[NFFT];
kiss_fft_scalar sout[NFFT];
kiss_fft_cfg kiss_fft_state;
kiss_fftr_cfg kiss_fftr_state;
kiss_fft_scalar rin[NFFT+2];
kiss_fft_scalar rout[NFFT+2];
kiss_fft_scalar zero;
memset(&zero,0,sizeof(zero) ); // ugly way of setting short,int,float,double, or __m128 to zero
for (i=0;i<NFFT;++i) {
rin[i] = rand_scalar();
#if defined(FIXED_POINT) && defined(DOUBLE_PRECISION)
rin[i] *= 32768;
#endif
cin[i].r = rin[i];
cin[i].i = zero;
}
kiss_fft_state = kiss_fft_alloc(NFFT,0,0);
kiss_fftr_state = kiss_fftr_alloc(NFFT,0,0);
kiss_fft(kiss_fft_state,cin,cout);
kiss_fftr(kiss_fftr_state,rin,sout);
printf( "nfft=%d, inverse=%d, snr=%g\n",
NFFT,0, snr_compare(cout,sout,(NFFT/2)) );
memset(cin,0,sizeof(cin));
cin[0].r = rand_scalar();
cin[NFFT/2].r = rand_scalar();
for (i=1;i< NFFT/2;++i) {
//cin[i].r = (kiss_fft_scalar)(rand()-RAND_MAX/2);
cin[i].r = rand_scalar();
cin[i].i = rand_scalar();
}
// conjugate symmetry of real signal
for (i=1;i< NFFT/2;++i) {
cin[NFFT-i].r = cin[i].r;
cin[NFFT-i].i = - cin[i].i;
}
#ifdef FIXED_POINT
#ifdef DOUBLE_PRECISION
for (i=0;i< NFFT;++i) {
cin[i].r *= 32768;
cin[i].i *= 32768;
}
#endif
for (i=0;i< NFFT;++i) {
cin[i].r /= NFFT;
cin[i].i /= NFFT;
}
#endif
fin[0] = cin[0].r;
fin[1] = cin[NFFT/2].r;
for (i=1;i< NFFT/2;++i)
{
fin[2*i] = cin[i].r;
fin[2*i+1] = cin[i].i;
}
kiss_ifft(kiss_fft_state,cin,cout);
kiss_fftri(kiss_fftr_state,fin,rout);
/*
printf(" results from inverse kiss_fft : (%f,%f), (%f,%f), (%f,%f), (%f,%f), (%f,%f) ...\n "
, (float)cout[0].r , (float)cout[0].i , (float)cout[1].r , (float)cout[1].i , (float)cout[2].r , (float)cout[2].i , (float)cout[3].r , (float)cout[3].i , (float)cout[4].r , (float)cout[4].i
);
printf(" results from inverse kiss_fftr: %f,%f,%f,%f,%f ... \n"
,(float)rout[0] ,(float)rout[1] ,(float)rout[2] ,(float)rout[3] ,(float)rout[4]);
*/
for (i=0;i<NFFT;++i) {
sout[i] = cout[i].r;
}
printf( "nfft=%d, inverse=%d, snr=%g\n",
NFFT,1, snr_compare_scal(rout,sout,NFFT) );
free(kiss_fft_state);
free(kiss_fftr_state);
return ret;
}
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