AudioEspressifFFT.h

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#pragma once
 
#include "AudioFFT.h"
#include "esp_dsp.h"
 
namespace audio_tools {
 
class FFTDriverEspressifFFT : public FFTDriver {
    public:
        bool begin(int len) override {
            this->len = len;
            int alloc_size = len * 2;
            fft_data.resize(alloc_size);
            table_buffer.resize(CONFIG_DSP_MAX_FFT_SIZE);
            assert(table_buffer.data() != nullptr);
            assert(fft_data.data() != nullptr);
            ret = dsps_fft2r_init_fc32(table_buffer.data(), CONFIG_DSP_MAX_FFT_SIZE);
            if (ret  != ESP_OK){
                LOGE("dsps_fft2r_init_fc32 %d", ret);
            }
            return fft_data.data()!=nullptr && ret == ESP_OK;
        }
 
        void end() override {
            dsps_fft2r_deinit_fc32();
            fft_data.resize(0);
            table_buffer.resize(0);
        }
 
        void setValue(int idx, float value) override {
            if (idx<len){
                fft_data[idx*2] = value;
                fft_data[idx*2 + 1] = 0.0f;
            }
        }
 
        float getValue(int idx) override { return fft_data[idx * 2]; }
 
        void fft() override {
            ret = dsps_fft2r_fc32(fft_data.data(), len);
            if (ret  != ESP_OK){
                LOGE("dsps_fft2r_fc32 %d", ret);
            }
            // Bit reverse 
            ret = dsps_bit_rev_fc32(fft_data.data(), len);
            if (ret  != ESP_OK){
                LOGE("dsps_bit_rev_fc32 %d", ret);
            }
            // Convert one complex vector to two complex vectors
            ret = dsps_cplx2reC_fc32(fft_data.data(), len);
            if (ret  != ESP_OK){
                LOGE("dsps_cplx2reC_fc32 %d", ret);
            }
        };
 
        void rfft() override {
            conjugate();
            ret = dsps_fft2r_fc32(fft_data.data(), len);
            if (ret  != ESP_OK){
                LOGE("dsps_fft2r_fc32 %d", ret);
            }
            conjugate();
            // Bit reverse 
            ret = dsps_bit_rev_fc32(fft_data.data(), len);
            if (ret  != ESP_OK){
                LOGE("dsps_bit_rev_fc32 %d", ret);
            }
            // Convert one complex vector to two complex vectors
            ret = dsps_cplx2reC_fc32(fft_data.data(), len);
            if (ret  != ESP_OK){
                LOGE("dsps_cplx2reC_fc32 %d", ret);
            }
        }
 
        void conjugate(){
            FFTBin bin;
            for (int j=0;j<len;j++){
                getBin(j, bin);
                bin.conjugate();
                setBin(j, bin);
            }
        }
 
        float magnitude(int idx) override { 
            return sqrt(magnitudeFast(idx));
        }
 
        float magnitudeFast(int idx) override { 
            return (fft_data[idx*2] * fft_data[idx*2] + fft_data[idx*2+1] * fft_data[idx*2+1]);
        }
        bool setBin(int pos, float real, float img) override {
            if (pos>=len) return false;
            fft_data[pos*2] = real;
            fft_data[pos*2+1] = img;
            return true;
        }
        
        bool setBin(int pos, FFTBin &bin)  { return FFTDriver::setBin(pos, bin);}
 
        bool getBin(int pos, FFTBin &bin) override { 
            if (pos>=len) return false;
            bin.real = fft_data[pos*2];
            bin.img = fft_data[pos*2+1];
            return true;
        }
 
        bool isReverseFFT() override {return true;}
 
        bool isValid() override{ return fft_data.data()!=nullptr && ret==ESP_OK; }
 
        esp_err_t ret;
        Vector<float> fft_data{0};
        Vector<float> table_buffer{0};
        int len=0;
 
};
class AudioEspressifFFT : public AudioFFTBase {
    public:
        AudioEspressifFFT():AudioFFTBase(new FFTDriverEspressifFFT()) {}
 
        float *dataArray() {
            return driverEx()->fft_data.data();
        }
 
        FFTDriverEspressifFFT* driverEx() {
            return (FFTDriverEspressifFFT*)driver();
        }
};
 
 
}