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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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15
kiss_fftr.c
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@ -80,6 +80,7 @@ void kiss_fftr(const void * cfg,const kiss_fft_scalar *timedata,kiss_fft_cpx *fr
freqdata[0].r = st->tmpbuf[0].r + st->tmpbuf[0].i;
freqdata[0].i = 0;
C_FIXDIV(freqdata[0],2);
for (k=1;k <= N/2 ; ++k ) {
kiss_fft_cpx fpnk,fpk,f1k,f2k,tw;
@ -87,22 +88,23 @@ void kiss_fftr(const void * cfg,const kiss_fft_scalar *timedata,kiss_fft_cpx *fr
fpk = st->tmpbuf[k];
fpnk.r = st->tmpbuf[N-k].r;
fpnk.i = -st->tmpbuf[N-k].i;
C_FIXDIV(fpk,2);
C_FIXDIV(fpnk,2);
C_ADD( f1k, fpk , fpnk );
C_SUB( f2k, fpk , fpnk );
C_MUL( tw , f2k , st->super_twiddles[k]);
C_ADD( freqdata[k] , f1k ,tw);
freqdata[k].r /= 2;
freqdata[k].i /= 2;
freqdata[k].r = (f1k.r + tw.r) / 2;
freqdata[k].i = (f1k.i + tw.i) / 2;
freqdata[N-k].r = f1k.r - tw.r;
freqdata[N-k].i = - (f1k.i - tw.i);
freqdata[N-k].r /= 2;
freqdata[N-k].i /= 2;
freqdata[N-k].r = (f1k.r - tw.r)/2;
freqdata[N-k].i = - (f1k.i - tw.i)/2;
}
freqdata[N].r = st->tmpbuf[0].r - st->tmpbuf[0].i;
freqdata[N].i = 0;
C_FIXDIV(freqdata[N],2);
}
void kiss_fftri(const void * cfg,const kiss_fft_cpx *freqdata,kiss_fft_scalar *timedata)
@ -120,6 +122,7 @@ void kiss_fftri(const void * cfg,const kiss_fft_cpx *freqdata,kiss_fft_scalar *t
st->tmpbuf[0].r = freqdata[0].r + freqdata[N].r;
st->tmpbuf[0].i = freqdata[0].r - freqdata[N].r;
for (k = 1; k <= N / 2; ++k) {
kiss_fft_cpx fk, fnkc, fek, fok, tmpbuf;
fk = freqdata[k];