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changed alloc functions to allow for initialization of user-supplied buffer

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This commit is contained in:
Mark Borgerding
2003-12-14 03:02:30 +00:00
parent ab32979a47
commit 559c14b49b
11 changed files with 135 additions and 112 deletions
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40
kiss_fftr.c
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@ -21,45 +21,47 @@ typedef struct {
kiss_fft_cpx * super_twiddles;
}kiss_fftr_state;
void * kiss_fftr_alloc(int nfft,int inverse_fft)
void * kiss_fftr_alloc(int nfft,int inverse_fft,void * mem,size_t * lenmem)
{
int i;
kiss_fftr_state *st = NULL;
int subsize;
if (nfft&1) {
size_t subsize, memneeded;
if (nfft & 1) {
/*fprintf(stderr,"Real FFT optimization must be even.\n"); */
return NULL;
}
nfft >>= 1;
subsize = kf_allocsize(nfft);
kiss_fft_alloc (nfft, inverse_fft, NULL, &subsize);
memneeded = sizeof(kiss_fftr_state) + subsize + sizeof(kiss_fft_cpx) * ( nfft * 2);
st = (kiss_fftr_state *) malloc ( sizeof(kiss_fftr_state)
+ subsize + sizeof(kiss_fft_cpx) * ( nfft * 2) );
if (lenmem == NULL) {
st = (kiss_fftr_state *) malloc (memneeded);
} else {
if (*lenmem >= memneeded)
st = (kiss_fftr_state *) mem;
*lenmem = memneeded;
}
if (!st)
return NULL;
st->minus3 = -3;
st->substate = (kiss_fft_state *)(st+1); /*just beyond kiss_fftr_state struct */
st->tmpbuf = (kiss_fft_cpx*)(((char*)st->substate) + subsize);
st->super_twiddles = st->tmpbuf + nfft;
kf_init_state (st->substate, nfft, inverse_fft);
st->substate = (kiss_fft_state *) (st + 1); /*just beyond kiss_fftr_state struct */
st->tmpbuf = (kiss_fft_cpx *) (((char *) st->substate) + subsize);
st->super_twiddles = st->tmpbuf + nfft;
kiss_fft_alloc(nfft, inverse_fft, st->substate, &subsize);
for (i=0;i<nfft;++i) {
double phase = -3.14159265358979323846264338327 * ( (double)i / nfft + .5);
for (i = 0; i < nfft; ++i) {
double phase =
-3.14159265358979323846264338327 * ((double) i / nfft + .5);
if (inverse_fft)
phase *= -1;
st->super_twiddles[i] = kf_cexp( phase );
st->super_twiddles[i] = kf_cexp (phase);
}
return st;
}
static void pcpx( kiss_fft_cpx * c)
{
printf("%g + %gi\n",c->r,c->i);
}
void kiss_fftr(const void * cfg,const kiss_fft_scalar *timedata,kiss_fft_cpx *freqdata)
{
/* input buffer timedata is stored row-wise */