diff options
| -rw-r--r-- | libcelt/Makefile.am | 6 | ||||
| -rw-r--r-- | libcelt/_kiss_fft_guts.h | 2 | ||||
| -rw-r--r-- | libcelt/kiss_fft.c | 90 | ||||
| -rw-r--r-- | libcelt/kiss_fftr.c | 173 | ||||
| -rw-r--r-- | libcelt/kiss_fftr.h | 48 | ||||
| -rw-r--r-- | tests/Makefile.am | 15 | ||||
| -rw-r--r-- | tests/dft-test.c | 79 | ||||
| -rw-r--r-- | tests/real-fft-test.c | 176 |
8 files changed, 509 insertions, 80 deletions
diff --git a/libcelt/Makefile.am b/libcelt/Makefile.am index 5e0b20d..ec2e4d2 100644 --- a/libcelt/Makefile.am +++ b/libcelt/Makefile.am @@ -16,8 +16,8 @@ lib_LTLIBRARIES = libcelt.la # Sources for compilation in the library libcelt_la_SOURCES = bands.c bitrdec.c bitree.c bitrenc.c celt.c cwrs.c \ ecintrin.h entcode.c entdec.c entenc.c fftwrap.c header.c kiss_fft.c \ - laplace.c mdct.c modes.c pitch.c psy.c quant_bands.c quant_pitch.c \ - rangedec.c rangeenc.c rate.c smallft.c vq.c + kiss_fftr.c laplace.c mdct.c modes.c pitch.c psy.c quant_bands.c \ + quant_pitch.c rangedec.c rangeenc.c rate.c smallft.c vq.c #noinst_HEADERS = @@ -25,7 +25,7 @@ libcelt_la_LDFLAGS = -version-info @CELT_LT_CURRENT@:@CELT_LT_REVISION@:@CELT_LT noinst_HEADERS = arch.h bands.h bitrdec.h bitree.h bitrenc.h cwrs.h \ ecintrin.h entcode.h entdec.h entenc.h fftwrap.h kiss_fft.h \ - _kiss_fft_guts.h laplace.h mdct.h \ + kiss_fftr.h _kiss_fft_guts.h laplace.h mdct.h \ mfrngcod.h modes.h os_support.h pgain_table.h pitch.h psy.h \ quant_bands.h quant_pitch.h rate.h smallft.h vq.h diff --git a/libcelt/_kiss_fft_guts.h b/libcelt/_kiss_fft_guts.h index 449194b..07403e4 100644 --- a/libcelt/_kiss_fft_guts.h +++ b/libcelt/_kiss_fft_guts.h @@ -20,7 +20,6 @@ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND and defines typedef struct { kiss_fft_scalar r; kiss_fft_scalar i; }kiss_fft_cpx; */ #include "kiss_fft.h" -//#include "math_approx.h" #define MAXFACTORS 32 /* e.g. an fft of length 128 has 4 factors @@ -32,6 +31,7 @@ struct kiss_fft_state{ int nfft; int inverse; int factors[2*MAXFACTORS]; + int *bitrev; kiss_fft_cpx twiddles[1]; }; diff --git a/libcelt/kiss_fft.c b/libcelt/kiss_fft.c index e254f27..b79c9bd 100644 --- a/libcelt/kiss_fft.c +++ b/libcelt/kiss_fft.c @@ -317,11 +317,11 @@ static void kf_bfly_generic( } } } - + static -void kf_shuffle( - kiss_fft_cpx * Fout, - const kiss_fft_cpx * f, +void compute_bitrev_table( + int * Fout, + int f, const size_t fstride, int in_stride, int * factors, @@ -337,14 +337,14 @@ void kf_shuffle( int j; for (j=0;j<p;j++) { - Fout[j] = *f; + Fout[j] = f; f += fstride*in_stride; } } else { int j; for (j=0;j<p;j++) { - kf_shuffle( Fout , f, fstride*p, in_stride, factors,st); + compute_bitrev_table( Fout , f, fstride*p, in_stride, factors,st); f += fstride*in_stride; Fout += m; } @@ -364,69 +364,21 @@ void kf_work( int m2 ) { - int i; + int i; kiss_fft_cpx * Fout_beg=Fout; const int p=*factors++; /* the radix */ const int m=*factors++; /* stage's fft length/p */ -#if 0 - /*printf ("fft %d %d %d %d %d %d\n", p*m, m, p, s2, fstride*in_stride, N);*/ - if (m==1) - { - /* int j; - for (j=0;j<p;j++) - { - Fout[j] = *f; - f += fstride*in_stride; - }*/ - } else { - int j; - for (j=0;j<p;j++) - { - kf_work( Fout , f, fstride*p, in_stride, factors,st, N*p, fstride*in_stride, m); - f += fstride*in_stride; - Fout += m; - } - } - - Fout=Fout_beg; - - switch (p) { - case 2: kf_bfly2(Fout,fstride,st,m); break; - case 3: kf_bfly3(Fout,fstride,st,m); break; - case 4: kf_bfly4(Fout,fstride,st,m); break; - case 5: kf_bfly5(Fout,fstride,st,m); break; - default: kf_bfly_generic(Fout,fstride,st,m,p); break; - } -#else /*printf ("fft %d %d %d %d %d %d %d\n", p*m, m, p, s2, fstride*in_stride, N, m2);*/ - if (m==1) - { - /*for (i=0;i<N;i++) - { - int j; - Fout = Fout_beg+i*m2; - const kiss_fft_cpx * f2 = f+i*s2; - for (j=0;j<p;j++) - { - *Fout++ = *f2; - f2 += fstride*in_stride; - } - }*/ - }else{ - kf_work( Fout , f, fstride*p, in_stride, factors,st, N*p, fstride*in_stride, m); - } + if (m!=1) + kf_work( Fout , f, fstride*p, in_stride, factors,st, N*p, fstride*in_stride, m); - - - - switch (p) { - case 2: kf_bfly2(Fout,fstride,st,m, N, m2); break; - case 3: for (i=0;i<N;i++){Fout=Fout_beg+i*m2; kf_bfly3(Fout,fstride,st,m);} break; - case 4: kf_bfly4(Fout,fstride,st,m, N, m2); break; - case 5: for (i=0;i<N;i++){Fout=Fout_beg+i*m2; kf_bfly5(Fout,fstride,st,m);} break; - default: for (i=0;i<N;i++){Fout=Fout_beg+i*m2; kf_bfly_generic(Fout,fstride,st,m,p);} break; + switch (p) { + case 2: kf_bfly2(Fout,fstride,st,m, N, m2); break; + case 3: for (i=0;i<N;i++){Fout=Fout_beg+i*m2; kf_bfly3(Fout,fstride,st,m);} break; + case 4: kf_bfly4(Fout,fstride,st,m, N, m2); break; + case 5: for (i=0;i<N;i++){Fout=Fout_beg+i*m2; kf_bfly5(Fout,fstride,st,m);} break; + default: for (i=0;i<N;i++){Fout=Fout_beg+i*m2; kf_bfly_generic(Fout,fstride,st,m,p);} break; } -#endif } /* facbuf is populated by p1,m1,p2,m2, ... @@ -495,6 +447,10 @@ kiss_fft_cfg kiss_fft_alloc(int nfft,int inverse_fft,void * mem,size_t * lenmem } #endif kf_factor(nfft,st->factors); + + /* bitrev */ + st->bitrev = celt_alloc(sizeof(int)*(nfft)); + compute_bitrev_table(st->bitrev, 0, 1,1, st->factors,st); } return st; } @@ -507,11 +463,11 @@ void kiss_fft_stride(kiss_fft_cfg st,const kiss_fft_cpx *fin,kiss_fft_cpx *fout, if (fin == fout) { celt_fatal("In-place FFT not supported"); - /*CHECKBUF(tmpbuf,ntmpbuf,st->nfft); - kf_work(tmpbuf,fin,1,in_stride, st->factors,st); - SPEEX_MOVE(fout,tmpbuf,st->nfft);*/ } else { - kf_shuffle( fout, fin, 1,in_stride, st->factors,st); + /* Bit-reverse the input */ + int i; + for (i=0;i<st->nfft;i++) + fout[i] = fin[st->bitrev[i]]; kf_work( fout, fin, 1,in_stride, st->factors,st, 1, in_stride, 1); } } diff --git a/libcelt/kiss_fftr.c b/libcelt/kiss_fftr.c new file mode 100644 index 0000000..613a262 --- /dev/null +++ b/libcelt/kiss_fftr.c @@ -0,0 +1,173 @@ +/* +Original version: +Copyright (c) 2003-2004, Mark Borgerding +Followed by heavy modifications: +Copyright (c) 2007-2008, Jean-Marc Valin + + +All rights reserved. + +Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: + + * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. + * Neither the author nor the names of any contributors may be used to endorse or promote products derived from this software without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +*/ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include "os_support.h" +#include "kiss_fftr.h" +#include "_kiss_fft_guts.h" + +struct kiss_fftr_state{ + kiss_fft_cfg substate; + kiss_fft_cpx * tmpbuf; + kiss_fft_cpx * super_twiddles; +#ifdef USE_SIMD + long pad; +#endif +}; + +kiss_fftr_cfg kiss_fftr_alloc(int nfft,int inverse_fft,void * mem,size_t * lenmem) +{ + int i; + kiss_fftr_cfg st = NULL; + size_t subsize, memneeded; + + if (nfft & 1) { + celt_warning("Real FFT optimization must be even.\n"); + return NULL; + } + nfft >>= 1; + + kiss_fft_alloc (nfft, inverse_fft, NULL, &subsize); + memneeded = sizeof(struct kiss_fftr_state) + subsize + sizeof(kiss_fft_cpx) * ( nfft * 2); + + if (lenmem == NULL) { + st = (kiss_fftr_cfg) KISS_FFT_MALLOC (memneeded); + } else { + if (*lenmem >= memneeded) + st = (kiss_fftr_cfg) mem; + *lenmem = memneeded; + } + if (!st) + return NULL; + + st->substate = (kiss_fft_cfg) (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); + +#ifdef FIXED_POINT + for (i=0;i<nfft;++i) { + celt_word32_t phase = i+(nfft>>1); + kf_cexp2(st->super_twiddles+i, DIV32(SHL32(phase,16),nfft)); + } +#else + for (i=0;i<nfft;++i) { + const double pi=3.14159265358979323846264338327; + double phase = pi*(((double)i) /nfft + .5); + kf_cexp(st->super_twiddles+i, phase ); + } +#endif + return st; +} + +void kiss_fftr(kiss_fftr_cfg st,const kiss_fft_scalar *timedata,kiss_fft_scalar *freqdata) +{ + /* input buffer timedata is stored row-wise */ + int k,ncfft; + kiss_fft_cpx f2k,tdc; + celt_word32_t f1kr, f1ki, twr, twi; + + if ( st->substate->inverse) { + celt_fatal("kiss fft usage error: improper alloc\n"); + } + + ncfft = st->substate->nfft; + + /*perform the parallel fft of two real signals packed in real,imag*/ + kiss_fft( st->substate , (const kiss_fft_cpx*)timedata, st->tmpbuf ); + /* The real part of the DC element of the frequency spectrum in st->tmpbuf + * contains the sum of the even-numbered elements of the input time sequence + * The imag part is the sum of the odd-numbered elements + * + * The sum of tdc.r and tdc.i is the sum of the input time sequence. + * yielding DC of input time sequence + * The difference of tdc.r - tdc.i is the sum of the input (dot product) [1,-1,1,-1... + * yielding Nyquist bin of input time sequence + */ + + tdc.r = st->tmpbuf[0].r; + tdc.i = st->tmpbuf[0].i; + C_FIXDIV(tdc,2); + CHECK_OVERFLOW_OP(tdc.r ,+, tdc.i); + CHECK_OVERFLOW_OP(tdc.r ,-, tdc.i); + freqdata[0] = tdc.r + tdc.i; + freqdata[2*ncfft-1] = tdc.r - tdc.i; + + for ( k=1;k <= ncfft/2 ; ++k ) + { + f2k.r = SHR32(SUB32(EXTEND32(st->tmpbuf[k].r), EXTEND32(st->tmpbuf[ncfft-k].r)),1); + f2k.i = PSHR32(ADD32(EXTEND32(st->tmpbuf[k].i), EXTEND32(st->tmpbuf[ncfft-k].i)),1); + + f1kr = SHL32(ADD32(EXTEND32(st->tmpbuf[k].r), EXTEND32(st->tmpbuf[ncfft-k].r)),13); + f1ki = SHL32(SUB32(EXTEND32(st->tmpbuf[k].i), EXTEND32(st->tmpbuf[ncfft-k].i)),13); + + twr = SHR32(ADD32(MULT16_16(f2k.r,st->super_twiddles[k].r),MULT16_16(f2k.i,st->super_twiddles[k].i)), 1); + twi = SHR32(SUB32(MULT16_16(f2k.i,st->super_twiddles[k].r),MULT16_16(f2k.r,st->super_twiddles[k].i)), 1); + +#ifdef FIXED_POINT + freqdata[2*k-1] = PSHR32(f1kr + twr, 15); + freqdata[2*k] = PSHR32(f1ki + twi, 15); + freqdata[2*(ncfft-k)-1] = PSHR32(f1kr - twr, 15); + freqdata[2*(ncfft-k)] = PSHR32(twi - f1ki, 15); +#else + freqdata[2*k-1] = .5f*(f1kr + twr); + freqdata[2*k] = .5f*(f1ki + twi); + freqdata[2*(ncfft-k)-1] = .5f*(f1kr - twr); + freqdata[2*(ncfft-k)] = .5f*(twi - f1ki); + +#endif + } +} + +void kiss_fftri(kiss_fftr_cfg st,const kiss_fft_scalar *freqdata,kiss_fft_scalar *timedata) +{ + /* input buffer timedata is stored row-wise */ + int k, ncfft; + + if (st->substate->inverse == 0) { + celt_fatal ("kiss fft usage error: improper alloc\n"); + } + + ncfft = st->substate->nfft; + + st->tmpbuf[0].r = freqdata[0] + freqdata[2*ncfft-1]; + st->tmpbuf[0].i = freqdata[0] - freqdata[2*ncfft-1]; + + for (k = 1; k <= ncfft / 2; ++k) { + kiss_fft_cpx fk, fnkc, fek, fok, tmp; + fk.r = freqdata[2*k-1]; + fk.i = freqdata[2*k]; + fnkc.r = freqdata[2*(ncfft - k)-1]; + fnkc.i = -freqdata[2*(ncfft - k)]; + + C_ADD (fek, fk, fnkc); + C_SUB (tmp, fk, fnkc); + C_MUL (fok, tmp, st->super_twiddles[k]); + C_ADD (st->tmpbuf[k], fek, fok); + C_SUB (st->tmpbuf[ncfft - k], fek, fok); +#ifdef USE_SIMD + st->tmpbuf[ncfft - k].i *= _mm_set1_ps(-1.0); +#else + st->tmpbuf[ncfft - k].i *= -1; +#endif + } + kiss_fft (st->substate, st->tmpbuf, (kiss_fft_cpx *) timedata); +} diff --git a/libcelt/kiss_fftr.h b/libcelt/kiss_fftr.h new file mode 100644 index 0000000..fea12bb --- /dev/null +++ b/libcelt/kiss_fftr.h @@ -0,0 +1,48 @@ +#ifndef KISS_FTR_H +#define KISS_FTR_H + +#include "kiss_fft.h" +#ifdef __cplusplus +extern "C" { +#endif + + +/* + + Real optimized version can save about 45% cpu time vs. complex fft of a real seq. + + + + */ + +typedef struct kiss_fftr_state *kiss_fftr_cfg; + + +kiss_fftr_cfg kiss_fftr_alloc(int nfft,int inverse_fft,void * mem, size_t * lenmem); +/* + nfft must be even + + If you don't care to allocate space, use mem = lenmem = NULL +*/ + + +/* + input timedata has nfft scalar points + output freqdata has nfft/2+1 complex points, packed into nfft scalar points +*/ + +void kiss_fftr(kiss_fftr_cfg st,const kiss_fft_scalar *timedata,kiss_fft_scalar *freqdata); + +void kiss_fftri(kiss_fftr_cfg st,const kiss_fft_scalar *freqdata, kiss_fft_scalar *timedata); + +/* + input freqdata has nfft/2+1 complex points, packed into nfft scalar points + output timedata has nfft scalar points +*/ + +#define kiss_fftr_free speex_free + +#ifdef __cplusplus +} +#endif +#endif diff --git a/tests/Makefile.am b/tests/Makefile.am index 03c7ade..741ec77 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -1,18 +1,15 @@ INCLUDES = -I$(top_srcdir)/libcelt METASOURCES = AUTO -TESTS = type-test ectest cwrs32-test cwrs64-test +TESTS = type-test ectest cwrs32-test cwrs64-test real-fft-test dft-test -bin_PROGRAMS = type-test ectest cwrs32-test cwrs64-test +bin_PROGRAMS = type-test ectest cwrs32-test cwrs64-test real-fft-test dft-test type_test_SOURCES = type-test.c -type_test_LDADD = $(top_builddir)/libcelt/libcelt.la - ectest_SOURCES = ectest.c -ectest_LDADD = $(top_builddir)/libcelt/libcelt.la - cwrs32_test_SOURCES = cwrs32-test.c -cwrs32_test_LDADD = $(top_builddir)/libcelt/libcelt.la - cwrs64_test_SOURCES = cwrs64-test.c -cwrs64_test_LDADD = $(top_builddir)/libcelt/libcelt.la +real_fft_test_SOURCES = real-fft-test.c +dft_test_SOURCES = dft-test.c + +LDADD = $(top_builddir)/libcelt/libcelt.la diff --git a/tests/dft-test.c b/tests/dft-test.c new file mode 100644 index 0000000..4e29eb0 --- /dev/null +++ b/tests/dft-test.c @@ -0,0 +1,79 @@ +#include <stdio.h> +#include "kiss_fft.h" + + +void check(kiss_fft_cpx * in,kiss_fft_cpx * out,int nfft,int isinverse) +{ + int bin,k; + double errpow=0,sigpow=0; + + for (bin=0;bin<nfft;++bin) { + double ansr = 0; + double ansi = 0; + double difr; + double difi; + + for (k=0;k<nfft;++k) { + double phase = -2*M_PI*bin*k/nfft; + double re = cos(phase); + double im = sin(phase); + if (isinverse) + im = -im; + +#ifdef FIXED_POINT + re /= nfft; + im /= nfft; +#endif + + ansr += in[k].r * re - in[k].i * im; + ansi += in[k].r * im + in[k].i * re; + } + difr = ansr - out[bin].r; + difi = ansi - out[bin].i; + errpow += difr*difr + difi*difi; + sigpow += ansr*ansr+ansi*ansi; + } + printf("nfft=%d inverse=%d,snr = %f\n",nfft,isinverse,10*log10(sigpow/errpow) ); +} + +void test1d(int nfft,int isinverse) +{ + size_t buflen = sizeof(kiss_fft_cpx)*nfft; + + kiss_fft_cpx * in = (kiss_fft_cpx*)malloc(buflen); + kiss_fft_cpx * out= (kiss_fft_cpx*)malloc(buflen); + kiss_fft_cfg cfg = kiss_fft_alloc(nfft,isinverse,0,0); + int k; + + for (k=0;k<nfft;++k) { + in[k].r = (rand() % 65536) - 32768; + in[k].i = (rand() % 65536) - 32768; + } + + kiss_fft(cfg,in,out); + + check(in,out,nfft,isinverse); + + free(in); + free(out); + free(cfg); +} + +int main(int argc,char ** argv) +{ + if (argc>1) { + int k; + for (k=1;k<argc;++k) { + test1d(atoi(argv[k]),0); + test1d(atoi(argv[k]),1); + } + }else{ + test1d(32,0); + test1d(32,1); + test1d(120,0); + test1d(120,1); + test1d(105,0); + test1d(105,1); + } + return 0; +} diff --git a/tests/real-fft-test.c b/tests/real-fft-test.c new file mode 100644 index 0000000..532ed8d --- /dev/null +++ b/tests/real-fft-test.c @@ -0,0 +1,176 @@ +#include "kiss_fftr.h" +#include "_kiss_fft_guts.h" +#include <sys/times.h> +#include <time.h> +#include <unistd.h> +#include <stdio.h> +#include <string.h> + +static double cputime(void) +{ + struct tms t; + times(&t); + return (double)(t.tms_utime + t.tms_stime)/ sysconf(_SC_CLK_TCK) ; +} + +static +kiss_fft_scalar rand_scalar(void) +{ +#ifdef USE_SIMD + return _mm_set1_ps(rand()-RAND_MAX/2); +#else + kiss_fft_scalar s = (kiss_fft_scalar)(rand() -RAND_MAX/2); + return s/2; +#endif +} + +static +double snr_compare( kiss_fft_cpx * vec1,kiss_fft_scalar * vec2, int n) +{ + int k; + double sigpow=1e-10, noisepow=1e-10, err,snr; + + for (k=1;k<n;++k) { + sigpow += (double)vec1[k].r * (double)vec1[k].r + + (double)vec1[k].i * (double)vec1[k].i; + err = (double)vec1[k].r - (double)vec2[2*k-1]; + noisepow += err * err; + err = (double)vec1[k].i - (double)vec2[2*k]; + noisepow += err * err; + + } + snr = 10*log10( sigpow / noisepow ); + if (snr<10) { + printf( "\npoor snr: %f\n", snr); + exit(1); + } + return snr; +} + +static +double snr_compare_scal( kiss_fft_scalar * vec1,kiss_fft_scalar * vec2, int n) +{ + int k; + double sigpow=1e-10, noisepow=1e-10, err,snr; + + for (k=1;k<n;++k) { + sigpow += (double)vec1[k] * (double)vec1[k]; + err = (double)vec1[k] - (double)vec2[k]; + noisepow += err * err; + } + snr = 10*log10( sigpow / noisepow ); + if (snr<10) { + printf( "\npoor snr: %f\n", snr); + exit(1); + } + return snr; +} +#define NFFT 8*3*5 + +#ifndef NUMFFTS +#define NUMFFTS 10000 +#endif + + +int main(void) +{ + double ts,tfft,trfft; + int i; + kiss_fft_cpx cin[NFFT]; + kiss_fft_cpx cout[NFFT]; + kiss_fft_scalar fin[NFFT]; + kiss_fft_scalar sout[NFFT]; + kiss_fft_cfg kiss_fft_state; + kiss_fftr_cfg kiss_fftr_state; + + kiss_fft_scalar rin[NFFT+2]; + kiss_fft_scalar rout[NFFT+2]; + kiss_fft_scalar zero; + memset(&zero,0,sizeof(zero) ); // ugly way of setting short,int,float,double, or __m128 to zero + + srand(time(0)); + + for (i=0;i<NFFT;++i) { + rin[i] = rand_scalar(); + cin[i].r = rin[i]; + cin[i].i = zero; + } + + kiss_fft_state = kiss_fft_alloc(NFFT,0,0,0); + kiss_fftr_state = kiss_fftr_alloc(NFFT,0,0,0); + kiss_fft(kiss_fft_state,cin,cout); + kiss_fftr(kiss_fftr_state,rin,sout); + + printf( "nfft=%d, inverse=%d, snr=%g\n", + NFFT,0, snr_compare(cout,sout,(NFFT/2)) ); + ts = cputime(); + for (i=0;i<NUMFFTS;++i) { + kiss_fft(kiss_fft_state,cin,cout); + } + tfft = cputime() - ts; + + ts = cputime(); + for (i=0;i<NUMFFTS;++i) { + kiss_fftr( kiss_fftr_state, rin, sout ); + /* kiss_fftri(kiss_fftr_state,cout,rin); */ + } + trfft = cputime() - ts; + + printf("%d complex ffts took %gs, real took %gs\n",NUMFFTS,tfft,trfft); + + free(kiss_fft_state); + free(kiss_fftr_state); + + kiss_fft_state = kiss_fft_alloc(NFFT,1,0,0); + kiss_fftr_state = kiss_fftr_alloc(NFFT,1,0,0); + + memset(cin,0,sizeof(cin)); +#if 1 + cin[0].r = rand_scalar(); + cin[NFFT/2].r = rand_scalar(); + for (i=1;i< NFFT/2;++i) { + //cin[i].r = (kiss_fft_scalar)(rand()-RAND_MAX/2); + cin[i].r = rand_scalar(); + cin[i].i = rand_scalar(); + } +#else + cin[0].r = 12000; + cin[3].r = 12000; + cin[NFFT/2].r = 12000; +#endif + + // conjugate symmetry of real signal + for (i=1;i< NFFT/2;++i) { + cin[NFFT-i].r = cin[i].r; + cin[NFFT-i].i = - cin[i].i; + } + + fin[0] = cin[0].r; + fin[NFFT-1] = cin[NFFT/2].r; + for (i=1;i< NFFT/2;++i) + { + fin[2*i-1] = cin[i].r; + fin[2*i] = cin[i].i; + } + + kiss_fft(kiss_fft_state,cin,cout); + kiss_fftri(kiss_fftr_state,fin,rout); + /* + printf(" results from inverse kiss_fft : (%f,%f), (%f,%f), (%f,%f), (%f,%f), (%f,%f) ...\n " + , (float)cout[0].r , (float)cout[0].i , (float)cout[1].r , (float)cout[1].i , (float)cout[2].r , (float)cout[2].i , (float)cout[3].r , (float)cout[3].i , (float)cout[4].r , (float)cout[4].i + ); + + printf(" results from inverse kiss_fftr: %f,%f,%f,%f,%f ... \n" + ,(float)rout[0] ,(float)rout[1] ,(float)rout[2] ,(float)rout[3] ,(float)rout[4]); +*/ + for (i=0;i<NFFT;++i) { + sout[i] = cout[i].r; + } + + printf( "nfft=%d, inverse=%d, snr=%g\n", + NFFT,1, snr_compare_scal(rout,sout,NFFT) ); + free(kiss_fft_state); + free(kiss_fftr_state); + + return 0; +} |