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fixed scaling for short real

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moved fft.py from ./ to sample_code
This commit is contained in:
Mark Borgerding
2003-12-14 05:13:11 +00:00
parent 559c14b49b
commit 573536f48f
14 changed files with 96 additions and 244 deletions
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30
test/test_real.c
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@ -1,5 +1,6 @@
#include "kiss_fft.h"
#include "_kiss_fft_guts.h"
#include <sys/times.h>
#include <time.h>
#include <unistd.h>
static double cputime()
@ -9,8 +10,6 @@ static double cputime()
return (double)(t.tms_utime + t.tms_stime)/ sysconf(_SC_CLK_TCK) ;
}
double snr_compare( kiss_fft_cpx * vec1,kiss_fft_cpx * vec2, int n)
{
int k;
@ -18,15 +17,19 @@ double snr_compare( kiss_fft_cpx * vec1,kiss_fft_cpx * vec2, int n)
sigpow = noisepow = .00000000000000000001;
for (k=0;k<n;++k) {
sigpow += vec1[k].r * vec1[k].r +
vec1[k].i * vec1[k].i;
err = vec1[k].r - vec2[k].r;
sigpow += (double)vec1[k].r * (double)vec1[k].r +
(double)vec1[k].i * (double)vec1[k].i;
err = (double)vec1[k].r - (double)vec2[k].r;
noisepow += err * err;
err = vec1[k].i - vec2[k].i;
err = (double)vec1[k].i - (double)vec2[k].i;
noisepow += err * err;
if (vec1[k].r)
scale += vec2[k].r / vec1[k].r;
scale +=(double) vec2[k].r / (double)vec1[k].r;
/*
fprintf(stderr,"vec1=");pcpx(vec1+k);
fprintf(stderr,"vec2=");pcpx(vec2+k);
*/
}
snr = 10*log10( sigpow / noisepow );
scale /= n;
@ -38,17 +41,13 @@ double snr_compare( kiss_fft_cpx * vec1,kiss_fft_cpx * vec2, int n)
#ifndef RANDOM
#define NFFT 8
#else
#define NFFT 2*3*5*7*11
#define NFFT 8*3*5
#endif
#ifndef NUMFFTS
#define NUMFFTS 1000
#endif
void pcpx(const char * msg, kiss_fft_cpx * c)
{
printf("%s: %g + %gi\n",msg,c->r,c->i);
}
int main()
{
@ -62,6 +61,7 @@ int main()
void * kiss_fft_state;
void * kiss_fftr_state;
srand(time(0));
for (i=0;i<NFFT;++i) {
#ifdef RANDOM
@ -69,7 +69,6 @@ int main()
#endif
cin[i].r = sin[i];
cin[i].i = 0;
/* printf("in[%d]",i);pcpx("",cin+i); */
}
kiss_fft_state = kiss_fft_alloc(NFFT,0,0,0);
@ -106,9 +105,6 @@ int main()
for (i=0;i<NFFT;++i) {
sout[i].r = sin[i];
sout[i].i = 0;
/* printf("sin[%d] = %f\t",i,sin[i]);
printf("cin[%d]",i);pcpx("",cin+i);
printf("sout[%d]",i);pcpx("",sout+i); */
}
printf( "nfft=%d, inverse=%d, snr=%g\n",