/*  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;}