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took utility/test code out of main source file and moved down to sample_code

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Mark Borgerding
2003-08-10 15:39:15 +00:00
parent b95e3ea18a
commit a962dc2681
7 changed files with 313 additions and 81 deletions
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91
kiss_fft.c
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@ -168,96 +168,37 @@ void fft_work(int N,kiss_fft_cpx *f,const kiss_fft_cpx * twid,int twid_step)
}
/*
* void * kiss_fft_alloc(int nfft,int inverse_fft)
*
* User-callable function to allocate all necessary scratch space for the fft.
*
* The return value is a contiguous block of memory, allocated with malloc. As such,
* It can be freed with free(), rather than a kiss_fft-specific function.
* */
void * kiss_fft_alloc(int nfft,int inverse_fft)
{
kiss_fft_state * st=NULL;
// allocate one large buffer to hold the state and the buffers for twiddles and bit-rev indices
int size = sizeof(kiss_fft_state) + (nfft>>1)*sizeof(kiss_fft_cpx) + nfft*sizeof(int);
// allocate one large buffer to hold the state, twiddle buffers, and bit-rev indices
int size = sizeof(kiss_fft_state) + (nfft>>1)*sizeof(kiss_fft_cpx) + (nfft>>1)*sizeof(int);
st = ( kiss_fft_state *)malloc(size);
if (st) {
st->twiddle = (kiss_fft_cpx*)(st+1);
st->swap_indices = (int*)( st->twiddle + (nfft>>1) );
if (st) {
st->twiddle = (kiss_fft_cpx*)(st+1); // pointer just beyond the kiss_fft_state struct
st->swap_indices = (int*)( st->twiddle + (nfft>>1) );// pointer just beyond the twiddle buffer
st->nfft = nfft;
// initialize the twiddle factors
make_twiddles(st->twiddle,nfft,inverse_fft);
// create list of index-swaps
st->nswap = make_bit_reverse_indices(st->swap_indices,nfft);
}
return st;
}
void kiss_fft(const void * cfg,kiss_fft_cpx *f)
{
const kiss_fft_state * st = cfg;
fft_work(st->nfft, f, st->twiddle , 1 );
undo_bit_rev(f,st->swap_indices,st->nswap);
}
#ifdef FFT_UTIL
#include <stdio.h>
#include <string.h>
int main(int argc,char ** argv)
{
kiss_fft_cpx * buf=NULL;
void *st;
int nfft=1024;
int inverse_fft=0;
int scale=0;
kiss_fft_cpx scaling;
fprintf(stderr,"sizeof(kiss_fft_cpx) == %d\n",sizeof(kiss_fft_cpx) );
// parse args
while (argc>1 && argv[1][0]=='-'){
if (0==strcmp("-i",argv[1])) {
inverse_fft = 1;
}else if(0==strcmp("-s",argv[1])) {
scale = 1;
}
--argc;++argv;
}
if (argc>1) {
nfft = atoi(argv[1]);
}
// do we need to scale?
if (scale) {
#ifdef FIXED_POINT
if ( ! inverse_fft ) {
scaling.r = nfft;
scaling.i = nfft;
fprintf(stderr,"scaling by %d\n",scaling.r);
}
#else
if (inverse_fft ){
scaling.r = 1.0/nfft;
scaling.i = 1.0/nfft;
fprintf(stderr,"scaling by %e\n",scaling.r);
}
#endif
else
scale = 0; // no need
}
buf=(kiss_fft_cpx*)malloc( sizeof(kiss_fft_cpx) * nfft );
st = kiss_fft_alloc( nfft ,inverse_fft );
while ( fread( buf , sizeof(kiss_fft_cpx) , nfft , stdin ) > 0 ) {
kiss_fft( st , buf );
if (scale) {
int k;
for (k=0;k<nfft;++k) {
buf[k].r = buf[k].r * scaling.r;
buf[k].i = buf[k].i * scaling.i;
}
}
fwrite( buf , sizeof(kiss_fft_cpx) , nfft , stdout );
}
free(st);
free(buf);
return 0;
}
#endif