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getting ready for v 1_2_2

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This commit is contained in:
Mark Borgerding 2005-05-09 01:43:49 +00:00
parent 4722ccb12b
commit ba105600b4
3 changed files with 50 additions and 14 deletions
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9
CHANGELOG
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@ -1,9 +1,10 @@
1.2.2 (May 6, 2005) The Matthew release
Replaced fixed point division with multiply&shift. Thanks to Jean-Marc Valin for the prodding.
Added C_FIXDIV calls to real fft routines to prevent possible overflow when using fixed point.
Credit to Robert Oschler of robodance for pointing me towards the bug.
Replaced fixed point division with multiply&shift. Thanks to Jean-Marc Valin for
discussions regarding. Considerable speedup.
Corrected overflow protection in real fft routines when using fixed point.
Finder's Credit goes to Robert Oschler of robodance for pointing me at the bug.
This also led to the CHECK_OVERFLOW_OP macro.
1.2.1 (April 4, 2004)
compiles cleanly with just about every -W warning flag under the sun

41
_kiss_fft_guts.h
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@ -43,6 +43,13 @@ struct kiss_fft_state{
* */
#ifdef FIXED_POINT
#if defined(CHECK_OVERFLOW)
# define CHECK_OVERFLOW_OP(a,op,b) \
if ( (long)(a) op (long)(b) > 32767 || (long)(a) op (long)(b) < -32768 ) { \
fprintf(stderr,"WARNING:overflow @ " __FILE__ "(%d): (%d " #op" %d) = %ld\n",__LINE__,(a),(b),(long)(a) op (long)(b) ); }
#endif
# define smul(a,b) ( (long)(a)*(b) )
# define sround( x ) (short)( ( (x) + (1<<14) ) >>15 )
@ -53,7 +60,7 @@ struct kiss_fft_state{
(m).i = sround( smul((a).r,(b).i) + smul((a).i,(b).r) ); }while(0)
# define DIVSCALAR(x,k) \
(x) = sround( smul( x, 32768/k ) )
(x) = sround( smul( x, 32767/k ) )
# define C_FIXDIV(c,div) \
do { DIVSCALAR( (c).r , div); \
@ -75,14 +82,38 @@ struct kiss_fft_state{
(c).i *= (s); }while(0)
#endif
#ifndef CHECK_OVERFLOW_OP
# define CHECK_OVERFLOW_OP(a,op,b) /* noop */
#endif
#define C_ADD( res, a,b)\
do { (res).r=(a).r+(b).r; (res).i=(a).i+(b).i; }while(0)
do { \
CHECK_OVERFLOW_OP((a).r,+,(b).r)\
CHECK_OVERFLOW_OP((a).i,+,(b).i)\
(res).r=(a).r+(b).r; (res).i=(a).i+(b).i; \
}while(0)
#define C_SUB( res, a,b)\
do { (res).r=(a).r-(b).r; (res).i=(a).i-(b).i; }while(0)
do { \
CHECK_OVERFLOW_OP((a).r,-,(b).r)\
CHECK_OVERFLOW_OP((a).i,-,(b).i)\
(res).r=(a).r-(b).r; (res).i=(a).i-(b).i; \
}while(0)
#define C_ADDTO( res , a)\
do { (res).r += (a).r; (res).i += (a).i; }while(0)
do { \
CHECK_OVERFLOW_OP((res).r,+,(a).r)\
CHECK_OVERFLOW_OP((res).i,+,(a).i)\
(res).r += (a).r; (res).i += (a).i;\
}while(0)
#define C_SUBFROM( res , a)\
do { (res).r -= (a).r; (res).i -= (a).i; }while(0)
do {\
CHECK_OVERFLOW_OP((res).r,-,(a).r)\
CHECK_OVERFLOW_OP((res).i,-,(a).i)\
(res).r -= (a).r; (res).i -= (a).i; \
}while(0)
static
void kf_cexp(kiss_fft_cpx * x,double phase) /* returns e ** (j*phase) */

14
tools/kiss_fftr.c
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@ -65,6 +65,7 @@ void kiss_fftr(kiss_fftr_cfg st,const kiss_fft_scalar *timedata,kiss_fft_cpx *fr
{
/* input buffer timedata is stored row-wise */
int k,N;
kiss_fft_cpx fpnk,fpk,f1k,f2k,tw,tdc;
if ( st->substate->inverse) {
fprintf(stderr,"kiss fft usage error: improper alloc\n");
@ -76,12 +77,15 @@ void kiss_fftr(kiss_fftr_cfg st,const kiss_fft_scalar *timedata,kiss_fft_cpx *fr
/*perform the parallel fft of two real signals packed in real,imag*/
kiss_fft( st->substate , (const kiss_fft_cpx*)timedata, st->tmpbuf );
freqdata[0].r = st->tmpbuf[0].r + st->tmpbuf[0].i;
tdc.r = st->tmpbuf[0].r;
tdc.i = st->tmpbuf[0].i;
C_FIXDIV(tdc,2);
CHECK_OVERFLOW_OP(tdc.r ,+, tdc.i);
freqdata[0].r = tdc.r + tdc.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;
fpk = st->tmpbuf[k];
fpnk.r = st->tmpbuf[N-k].r;
@ -100,9 +104,9 @@ void kiss_fftr(kiss_fftr_cfg st,const kiss_fft_scalar *timedata,kiss_fft_cpx *fr
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;
CHECK_OVERFLOW_OP(tdc.r ,-, tdc.i);
freqdata[N].r = tdc.r - tdc.i;
freqdata[N].i = 0;
C_FIXDIV(freqdata[N],2);
}
void kiss_fftri(kiss_fftr_cfg st,const kiss_fft_cpx *freqdata,kiss_fft_scalar *timedata)