ref: 6f50522ff66bbebd9d899f71b6da71288c0a8d0d
dir: /modules/fftwrapper.c/
/* FFTwrapper.c - A wrapper for Fast Fourier Transforms Author: Nasca O. Paul, Tg. Mures, Romania De-classified and ported to C code by Paul Batchelor 2015 License: Public Domain This requires FFTW library (http://www.fftw.org) to compile and run. */ #include <stdlib.h> #include <math.h> #include <string.h> #include "soundpipe.h" #include "kiss_fftr.h" void FFTwrapper_create(FFTwrapper **fw, int fftsize) { FFTwrapper *fwp; *fw = malloc(sizeof(FFTwrapper)); fwp = *fw; fwp->fftsize = fftsize; #ifdef USE_FFTW3 fftw_real *tf1 = malloc(fftsize * sizeof(fftw_real)); fftw_real *tf2 = malloc(fftsize * sizeof(fftw_real)); fwp->tmpfftdata1 = tf1; fwp->tmpfftdata2 = tf2; fwp->planfftw = fftw_plan_r2r_1d(fftsize, fwp->tmpfftdata1, fwp->tmpfftdata1, FFTW_R2HC, FFTW_ESTIMATE); fwp->planfftw_inv = fftw_plan_r2r_1d(fftsize, fwp->tmpfftdata2, fwp->tmpfftdata2, FFTW_HC2R, FFTW_ESTIMATE); #else fwp->fft = kiss_fftr_alloc(fftsize, 0, NULL, NULL); fwp->ifft = kiss_fftr_alloc(fftsize, 1, NULL, NULL); fwp->tmp1 = KISS_FFT_MALLOC(sizeof(kiss_fft_cpx) * fftsize); fwp->tmp2 = KISS_FFT_MALLOC(sizeof(kiss_fft_cpx) * fftsize); memset(fwp->tmp1, 0, sizeof(kiss_fft_cpx) * fftsize); memset(fwp->tmp2, 0, sizeof(kiss_fft_cpx) * fftsize); #endif } void FFTwrapper_destroy(FFTwrapper **fw) { FFTwrapper *fwp = *fw; #ifdef USE_FFTW3 fftw_destroy_plan(fwp->planfftw); fftw_destroy_plan(fwp->planfftw_inv); free(fwp->tmpfftdata1); free(fwp->tmpfftdata2); #else kiss_fftr_free(fwp->fft); kiss_fftr_free(fwp->ifft); KISS_FFT_FREE(fwp->tmp1); KISS_FFT_FREE(fwp->tmp2); #endif free(*fw); } /* do the Fast Fourier Transform */ void smps2freqs(FFTwrapper *ft, SPFLOAT *smps, FFTFREQS *freqs) { int i; #ifdef USE_FFTW3 for (i = 0; i < ft->fftsize; i++) ft->tmpfftdata1[i]=smps[i]; fftw_execute(ft->planfftw); for (i = 0; i < ft->fftsize/2; i++) { freqs.c[i] = ft->tmpfftdata1[i]; if (i != 0) freqs.s[i] = ft->tmpfftdata1[ft->fftsize-i]; } ft->tmpfftdata2[ft->fftsize/2] = 0.0; #else kiss_fftr(ft->fft, smps, ft->tmp1); for (i = 0; i < ft->fftsize/2; i++) { freqs->c[i] = ft->tmp1[i].r; freqs->s[i] = ft->tmp1[i].i; } #endif } /* * do the Inverse Fast Fourier Transform */ void freqs2smps(FFTwrapper *ft, FFTFREQS *freqs, SPFLOAT *smps) { int i; #ifdef USE_FFTW3 ft->tmpfftdata2[ft->fftsize/2]=0.0; for (i=0; i<ft->fftsize/2 ;i++) { ft->tmpfftdata2[i]=freqs.c[i]; if (i != 0) ft->tmpfftdata2[ft->fftsize-i]=freqs.s[i]; } fftw_execute(ft->planfftw_inv); for (i = 0; i < ft->fftsize; i++) smps[i]=ft->tmpfftdata2[i]; #else for (i = 0; i < ft->fftsize / 2; i++) { ft->tmp2[i].r = freqs->c[i]; ft->tmp2[i].i = freqs->s[i]; } kiss_fftri(ft->ifft, ft->tmp2, smps); #endif } void newFFTFREQS(FFTFREQS *f,int size) { int i; SPFLOAT *c = malloc(size * sizeof(SPFLOAT)); SPFLOAT *s = malloc(size * sizeof(SPFLOAT)); f->c = c; f->s = s; for (i = 0; i<size ;i++) { f->c[i]=0.0; f->s[i]=0.0; }; } void deleteFFTFREQS(FFTFREQS *f) { free(f->c); free(f->s); f->c= f->s = NULL; }