sdrangel/libfreedv/codec2_fft.h

109 lines
2.8 KiB
C++

/*
* codec2_fft.h
*
* Created on: 17.09.2016
* Author: danilo
*/
#ifndef DRIVERS_FREEDV_CODEC2_FFT_H_
#define DRIVERS_FREEDV_CODEC2_FFT_H_
#include <assert.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <math.h>
#include <cstddef>
#include "codec2/comp.h"
#include "defines.h"
#include "kiss_fftr.h"
#ifdef FDV_ARM_MATH
#include "fdv_arm_math.h"
#else
#define USE_KISS_FFT
#endif
#ifdef USE_KISS_FFT
#include "kiss_fft.h"
#endif
namespace FreeDV
{
typedef COMP codec2_fft_cpx;
#ifdef USE_KISS_FFT
typedef kiss_fftr_cfg codec2_fftr_cfg;
typedef kiss_fft_cfg codec2_fft_cfg;
typedef kiss_fft_scalar codec2_fft_scalar;
#else
typedef float32_t codec2_fft_scalar;
typedef struct {
arm_rfft_fast_instance_f32* instance;
int inverse;
} codec2_fftr_struct;
typedef codec2_fftr_struct* codec2_fftr_cfg;
typedef struct {
const arm_cfft_instance_f32* instance;
int inverse;
} codec2_fft_struct;
typedef codec2_fft_struct* codec2_fft_cfg;
#endif
static inline void codec2_fftr(codec2_fftr_cfg cfg, codec2_fft_scalar* in, codec2_fft_cpx* out)
{
#ifdef USE_KISS_FFT
kiss_fftr(cfg, in, (kiss_fft_cpx*)out);
#else
arm_rfft_fast_f32(cfg->instance,in,(float*)out,cfg->inverse);
out->imag = 0; // remove out[FFT_ENC/2]->real stored in out[0].imag
#endif
}
static inline void codec2_fftri(codec2_fftr_cfg cfg, codec2_fft_cpx* in, codec2_fft_scalar* out)
{
#ifdef USE_KISS_FFT
kiss_fftri(cfg, (kiss_fft_cpx*)in, out);
#else
arm_rfft_fast_f32(cfg->instance,(float*)in,out,cfg->inverse);
// arm_scale_f32(out,cfg->instance->fftLenRFFT,out,cfg->instance->fftLenRFFT);
#endif
}
codec2_fft_cfg codec2_fft_alloc(int nfft, int inverse_fft, void* mem, std::size_t* lenmem);
codec2_fftr_cfg codec2_fftr_alloc(int nfft, int inverse_fft, void* mem, std::size_t* lenmem);
void codec2_fft_free(codec2_fft_cfg cfg);
void codec2_fftr_free(codec2_fftr_cfg cfg);
static inline void codec2_fft(codec2_fft_cfg cfg, codec2_fft_cpx* in, codec2_fft_cpx* out)
{
#ifdef USE_KISS_FFT
kiss_fft(cfg, (kiss_fft_cpx*)in, (kiss_fft_cpx*)out);
#else
memcpy(out,in,cfg->instance->fftLen*2*sizeof(float));
arm_cfft_f32(cfg->instance,(float*)out,cfg->inverse,0);
// TODO: this is not nice, but for now required to keep changes minimal
// however, since main goal is to reduce the memory usage
// we should convert to an in place interface
// on PC like platforms the overhead of using the "inplace" kiss_fft calls
// is neglectable compared to the gain in memory usage on STM32 platforms
if (cfg->inverse)
{
arm_scale_f32((float*)out,cfg->instance->fftLen,(float*)out,cfg->instance->fftLen*2);
}
#endif
}
void codec2_fft_inplace(codec2_fft_cfg cfg, codec2_fft_cpx* inout);
} // FreeDV
#endif