不韋 呂 / Mbed 2 deprecated F746_RealtimeSpectrumAnalyzer

Dependencies:   BSP_DISCO_F746NG BUTTON_GROUP LCD_DISCO_F746NG TS_DISCO_F746NG UIT_FFT_Real mbed

MyClasses/FFT_Analysis.cpp

Committer:
MikamiUitOpen
Date:
2015-12-14
Revision:
3:7c26b701f363
Parent:
2:095b360e0f54
Child:
4:99d4d5ea06a2

File content as of revision 3:7c26b701f363:

//-------------------------------------------------------
//  Class for spectrum analysis using FFT
//
//  2015/12/14, Copyright (c) 2015 MIKAMI, Naoki
//-------------------------------------------------------

#include "FFT_Analysis.hpp"

namespace Mikami
{
    FftAnalyzer::FftAnalyzer(int nData, int nFft)
        : AnalyzerBase(nData, nFft, nFft),
          xFft_(new float[nFft]),
          yFft_(new Complex[nFft/2+1]) {}

    FftAnalyzer::~FftAnalyzer()
    {
        delete[] xFft_;
        delete[] yFft_;
    }

    void FftAnalyzer::Analyze(const float xn[], float yn[])
    {
        wHm_.Execute(xn, xFft_);    // Windowing and zero-padding
        fft_.Execute(xFft_, yFft_); // Execute FFT
        
        // Translate to dB
        for (int n=0; n<=N_FFT_/2; n++)
            yn[n] = 10.0f*log10f(Norm(yFft_[n]));
    }
}