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libdspl-2.0/dspl/src/convolution/conv_fft.c

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New project structure for filter design algorithms Changes to be committed: deleted: dspl/src/conv.c new file: dspl/src/convolution.c new file: dspl/src/convolution/conv.c new file: dspl/src/convolution/conv_cmplx.c new file: dspl/src/convolution/conv_fft.c new file: dspl/src/convolution/conv_fft_cmplx.c new file: dspl/src/convolution/filter_iir.c deleted: dspl/src/ellipj.c deleted: dspl/src/filter_an.c deleted: dspl/src/filter_ap.c new file: dspl/src/filter_design.c new file: dspl/src/filter_design/bilinear.c new file: dspl/src/filter_design/butter_ap.c new file: dspl/src/filter_design/butter_ap_zp.c new file: dspl/src/filter_design/cheby1_ap.c new file: dspl/src/filter_design/cheby1_ap_zp.c new file: dspl/src/filter_design/cheby2_ap.c new file: dspl/src/filter_design/cheby2_ap_wp1.c new file: dspl/src/filter_design/cheby2_ap_zp.c new file: dspl/src/filter_design/ellip_ap.c new file: dspl/src/filter_design/ellip_ap_zp.c new file: dspl/src/filter_design/filter_freq_resp.c new file: dspl/src/filter_design/filter_ws1.c new file: dspl/src/filter_design/filter_zp2ab.c renamed: dspl/src/filter_fir.c -> dspl/src/filter_design/fir_linphase.c new file: dspl/src/filter_design/fir_linphase_lpf.c new file: dspl/src/filter_design/freqs.c new file: dspl/src/filter_design/freqs2time.c new file: dspl/src/filter_design/freqs_cmplx.c new file: dspl/src/filter_design/freqz.c new file: dspl/src/filter_design/group_delay.c renamed: dspl/src/filter_iir.c -> dspl/src/filter_design/iir.c new file: dspl/src/filter_design/iir_ap.c new file: dspl/src/filter_design/low2bp.c new file: dspl/src/filter_design/low2bs.c new file: dspl/src/filter_design/low2high.c new file: dspl/src/filter_design/low2low.c new file: dspl/src/filter_design/phase_delay.c new file: dspl/src/filter_design/ratcompos.c deleted: dspl/src/filter_ft.c new file: dspl/src/math_ellipj.c new file: dspl/src/math_ellipj/ellip_acd.c new file: dspl/src/math_ellipj/ellip_acd_cmplx.c new file: dspl/src/math_ellipj/ellip_asn.c new file: dspl/src/math_ellipj/ellip_asn_cmplx.c new file: dspl/src/math_ellipj/ellip_cd.c new file: dspl/src/math_ellipj/ellip_cd_cmplx.c new file: dspl/src/math_ellipj/ellip_landen.c new file: dspl/src/math_ellipj/ellip_modulareq.c new file: dspl/src/math_ellipj/ellip_rat.c new file: dspl/src/math_ellipj/ellip_sn.c new file: dspl/src/math_ellipj/ellip_sn_cmplx.c new file: dspl/src/types.c renamed: dspl/src/complex.c -> dspl/src/types/cmplx2re.c new file: dspl/src/types/re2cmplx.c new file: dspl/src/unwrap.c
2021-12-29 13:31:00 +00:00
/*
* Copyright (c) 2015-2020 Sergey Bakhurin
* Digital Signal Processing Library [http://dsplib.org]
*
* This file is part of DSPL.
*
* is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* DSPL is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Foobar. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "dspl.h"
#ifdef DOXYGEN_ENGLISH
/*! ****************************************************************************
\ingroup FILTER_CONV_GROUP
\fn int conv_fft(double* a, int na, double* b, int nb,
fft_t* pfft, int nfft, double* c)
\brief Real vectors fast linear convolution by using fast Fourier
transform algorithms
Function convolves two real vectors \f$ c = a * b\f$ length `na` and `nb`
in the frequency domain by using FFT algorithms. This approach provide
high-performance convolution which increases with `na` and `nb` increasing.
The output convolution is a vector `c` with length equal to `na + nb - 1`.
\param[in] a
Pointer to the first vector `a`. \n
Vector size is `[na x 1]`. \n \n
\param[in] na
Size of the first vector `a`. \n \n
\param[in] b
Pointer to the second vector `b`. \n
Vector size is `[nb x 1]`. \n \n
\param[in] nb
Size of the second vector `b`. \n \n
\param[in] pfft
Pointer to the structure `fft_t`. \n
Function changes `fft_t` structure fields so `fft_t` must
be clear before program returns. \n \n
\param[in] nfft
FFT size. \n
This parameter set which FFT size will be used
for overlapped frequency domain convolution. \n
FFT size must be more of minimal `na` and `nb` value.
For example if `na = 10`, `nb = 4` then `nfft` parameter must
be more than 4. \n
\param[out] c
Pointer to the convolution output vector \f$ c = a * b\f$. \n
Vector size is `[na + nb - 1 x 1]`. \n
Memory must be allocated. \n \n
\return `RES_OK` if convolution is calculated successfully. \n
Else \ref ERROR_CODE_GROUP "code error". \n \n
Example:
\include conv_fft_test.c
Program output:
\verbatim
conv_fft error: 0x00000000
conv error: 0x00000000
c[ 0] = -0.00 d[ 0] = 0.00
c[ 1] = -0.00 d[ 1] = 0.00
c[ 2] = 1.00 d[ 2] = 1.00
c[ 3] = 4.00 d[ 3] = 4.00
c[ 4] = 10.00 d[ 4] = 10.00
c[ 5] = 20.00 d[ 5] = 20.00
c[ 6] = 35.00 d[ 6] = 35.00
c[ 7] = 56.00 d[ 7] = 56.00
c[ 8] = 77.00 d[ 8] = 77.00
c[ 9] = 98.00 d[ 9] = 98.00
c[ 10] = 119.00 d[ 10] = 119.00
c[ 11] = 140.00 d[ 11] = 140.00
c[ 12] = 161.00 d[ 12] = 161.00
c[ 13] = 182.00 d[ 13] = 182.00
c[ 14] = 190.00 d[ 14] = 190.00
c[ 15] = 184.00 d[ 15] = 184.00
c[ 16] = 163.00 d[ 16] = 163.00
c[ 17] = 126.00 d[ 17] = 126.00
c[ 18] = 72.00 d[ 18] = 72.00
\endverbatim
\author Sergey Bakhurin www.dsplib.org
***************************************************************************** */
#endif
#ifdef DOXYGEN_RUSSIAN
/*! ****************************************************************************
\ingroup FILTER_CONV_GROUP
\fn int conv_fft(double* a, int na, double* b, int nb,
fft_t* pfft, double* c)
\brief Линейная свертка двух вещественных векторов с использованием алгоритмов
быстрого преобразования Фурье
Функция рассчитывает линейную свертку двух векторов \f$ c = a * b\f$ используя
секционную обработку с перекрытием в частотной области. Это позволяет сократить
вычислительные операции при расчете длинных сверток.
\param[in] a
Указатель на первый вектор \f$a\f$. \n
Размер вектора `[na x 1]`. \n \n
\param[in] na
Размер первого вектора. \n \n
\param[in] b
Указатель на второй вектор \f$b\f$. \n
Размер вектора `[nb x 1]`. \n \n
\param[in] nb
Размер второго вектора. \n \n
\param[in] pfft
Указатель на структуру `fft_t` алгоритма
быстрого преобразования Фурье. \n
Функция изменит состояние полей структуры `fft_t`,
поэтому структура должна быть очищена перед выходом из
программы для исключения утечек памяти. \n
\param[in] nfft
Размер алгоритма БПФ который будет использован для расчета
секционной свертки с перекрытием. \n
Данный параметр должен быть больше чем минимальное значение
размеров сворачиваемых векторов. \n
Например если `na=10`, а `nb=4`, то параметр `nfft` должен быть больше 4. \n
Библиотека поддерживает алгоритмы БПФ составной длины
\f$n = n_0 \times n_1 \times n_2 \times \ldots \times n_p \times m\f$,
где \f$n_i = 2,3,5,7\f$, а \f$m \f$ --- произвольный простой множитель
не превосходящий 46340 (см. описание функции \ref fft_create).
Однако, максимальное быстродействие достигается при использовании длин равных
степени двойки.
\param[out] c
Указатель на вектор свертки \f$ c = a * b\f$. \n
Размер вектора `[na + nb - 1 x 1]`. \n
Память должна быть выделена. \n \n
\return
`RES_OK` если свертка рассчитана успешно. \n
В противном случае \ref ERROR_CODE_GROUP "код ошибки".
\note
Данная функция наиболее эффективна при вычислении длинных сверток.
Пример использования функции:
\include conv_fft_test.c
Результат работы:
\verbatim
conv_fft error: 0x00000000
conv error: 0x00000000
c[ 0] = -0.00 d[ 0] = 0.00
c[ 1] = -0.00 d[ 1] = 0.00
c[ 2] = 1.00 d[ 2] = 1.00
c[ 3] = 4.00 d[ 3] = 4.00
c[ 4] = 10.00 d[ 4] = 10.00
c[ 5] = 20.00 d[ 5] = 20.00
c[ 6] = 35.00 d[ 6] = 35.00
c[ 7] = 56.00 d[ 7] = 56.00
c[ 8] = 77.00 d[ 8] = 77.00
c[ 9] = 98.00 d[ 9] = 98.00
c[ 10] = 119.00 d[ 10] = 119.00
c[ 11] = 140.00 d[ 11] = 140.00
c[ 12] = 161.00 d[ 12] = 161.00
c[ 13] = 182.00 d[ 13] = 182.00
c[ 14] = 190.00 d[ 14] = 190.00
c[ 15] = 184.00 d[ 15] = 184.00
c[ 16] = 163.00 d[ 16] = 163.00
c[ 17] = 126.00 d[ 17] = 126.00
c[ 18] = 72.00 d[ 18] = 72.00
\endverbatim
\author Бахурин Сергей. www.dsplib.org
***************************************************************************** */
#endif
int DSPL_API conv_fft(double* a, int na, double* b, int nb,
fft_t* pfft, int nfft, double* c)
{
complex_t *pa = NULL, *pb = NULL, *pc = NULL;
int err;
if(!a || !b || !c || !pfft)
return ERROR_PTR;
if(na<1 || nb < 1)
return ERROR_SIZE;
if(nfft<2)
return ERROR_FFT_SIZE;
pa = (complex_t*) malloc(na*sizeof(complex_t));
pb = (complex_t*) malloc(nb*sizeof(complex_t));
pc = (complex_t*) malloc((na+nb-1)*sizeof(complex_t));
re2cmplx(a, na, pa);
re2cmplx(b, nb, pb);
err = conv_fft_cmplx(pa, na, pb, nb, pfft, nfft, pc);
if(err != RES_OK)
goto exit_label;
err = cmplx2re(pc, na+nb-1, c, NULL);
exit_label:
if(pa) free(pa);
if(pb) free(pb);
if(pc) free(pc);
return err;
}