不韋 呂 / Mbed 2 deprecated F746_RealtimeSpectrumAnalyzer_MEMS_Mic

Version using MEMS microphone and CODEC for the program "F746_RealtimeSpectrumAnalyzer". "F746_RealtimeSpectrumAnalyzer" の入力を MEMS のマイクと CODEC に変更．このプログラムは Tomona Nanase さんが作成し DISCO-F746NG_Oscilloscope の名前で登録しているプログラムで， CODEC を使って入力する部分を参考にして作成．このプログラムの説明は，CQ出版社のインターフェース誌，2016年4月号に掲載．

Dependencies:   BSP_DISCO_F746NG BUTTON_GROUP LCD_DISCO_F746NG TS_DISCO_F746NG UIT_FFT_Real mbed

MyClasses_Functions/LPC_Analysis.cpp@8:e7dc8658c5cd, 2016-04-19 (annotated)

Committer:
MikamiUitOpen
Date:
Tue Apr 19 09:35:24 2016 +0000
Revision:
8:e7dc8658c5cd
Parent:
0:0e5131366580 
9

Who changed what in which revision?

UserRevisionLine numberNew contents of line
MikamiUitOpen 0:0e5131366580 1 //-------------------------------------------------------
MikamiUitOpen 0:0e5131366580 2 // Class for spectrum analysis using linear prediction
MikamiUitOpen 0:0e5131366580 3 //
MikamiUitOpen 0:0e5131366580 4 // 2015/12/15, Copyright (c) 2015 MIKAMI, Naoki
MikamiUitOpen 0:0e5131366580 5 //-------------------------------------------------------
MikamiUitOpen 0:0e5131366580 6
MikamiUitOpen 0:0e5131366580 7 #include "LPC_Analysis.hpp"
MikamiUitOpen 0:0e5131366580 8
MikamiUitOpen 0:0e5131366580 9 namespace Mikami
MikamiUitOpen 0:0e5131366580 10 {
MikamiUitOpen 0:0e5131366580 11 LpcAnalyzer::LpcAnalyzer(int nData, int nFft, int order)
MikamiUitOpen 0:0e5131366580 12 : AnalyzerBase(nData, nFft, nData-1), ORDER_(order),
MikamiUitOpen 0:0e5131366580 13 lp_(nData-1, order), an_(new float[order]),
MikamiUitOpen 0:0e5131366580 14 xFft_(new float[nFft]), yFft_(new Complex[nFft/2+1]) {}
MikamiUitOpen 0:0e5131366580 15
MikamiUitOpen 0:0e5131366580 16 LpcAnalyzer::~LpcAnalyzer()
MikamiUitOpen 0:0e5131366580 17 {
MikamiUitOpen 0:0e5131366580 18 delete[] an_;
MikamiUitOpen 0:0e5131366580 19 delete[] xFft_;
MikamiUitOpen 0:0e5131366580 20 delete[] yFft_;
MikamiUitOpen 0:0e5131366580 21 }
MikamiUitOpen 0:0e5131366580 22
MikamiUitOpen 0:0e5131366580 23 void LpcAnalyzer::Analyze(const float xn[], float yn[])
MikamiUitOpen 0:0e5131366580 24 {
MikamiUitOpen 0:0e5131366580 25 float em;
MikamiUitOpen 0:0e5131366580 26 lp_.Execute(xn, an_, em);
MikamiUitOpen 0:0e5131366580 27
MikamiUitOpen 0:0e5131366580 28 // To spectrum
MikamiUitOpen 0:0e5131366580 29 xFft_[0] = 1.0f;
MikamiUitOpen 0:0e5131366580 30 for (int n=0; n<ORDER_; n++) xFft_[n+1] = -an_[n];
MikamiUitOpen 0:0e5131366580 31 for (int n=ORDER_+1; n<N_FFT_; n++) xFft_[n] = 0.0f;
MikamiUitOpen 0:0e5131366580 32 fft_.Execute(xFft_, yFft_); // execute FFT
MikamiUitOpen 0:0e5131366580 33
MikamiUitOpen 0:0e5131366580 34 // Translate to dB
MikamiUitOpen 0:0e5131366580 35 for (int n=0; n<=N_FFT_/2; n++)
MikamiUitOpen 0:0e5131366580 36 yn[n] = 10.0f*log10f(em/Norm(yFft_[n]));
MikamiUitOpen 0:0e5131366580 37 }
MikamiUitOpen 0:0e5131366580 38 }