不韋 呂 / F746_Spectrogram

Realtime spectrogram for DISCO-F746NG. On-board MEMS microphone is used for input sound signal. リアルタイムスペクトログラム．入力：MEMSマイク

Dependencies:   F746_GUI F746_SAI_IO UIT_FFT_Real

MyClasses_Functions/FFT_Analysis.cpp@0:9470a174c910, 2016-05-22 (annotated)

Committer:
MikamiUitOpen
Date:
Sun May 22 06:28:40 2016 +0000
Revision:
0:9470a174c910
Child:
2:1f092ac020e1
1

Who changed what in which revision?

UserRevisionLine numberNew contents of line
MikamiUitOpen 0:9470a174c910 1 //-------------------------------------------------------
MikamiUitOpen 0:9470a174c910 2 // Class for spectrum analysis using FFT
MikamiUitOpen 0:9470a174c910 3 //
MikamiUitOpen 0:9470a174c910 4 // 2015/12/15, Copyright (c) 2015 MIKAMI, Naoki
MikamiUitOpen 0:9470a174c910 5 //-------------------------------------------------------
MikamiUitOpen 0:9470a174c910 6
MikamiUitOpen 0:9470a174c910 7 #include "FFT_Analysis.hpp"
MikamiUitOpen 0:9470a174c910 8
MikamiUitOpen 0:9470a174c910 9 namespace Mikami
MikamiUitOpen 0:9470a174c910 10 {
MikamiUitOpen 0:9470a174c910 11 FftAnalyzer::FftAnalyzer(int nData, int nFft)
MikamiUitOpen 0:9470a174c910 12 : AnalyzerBase(nData, nFft, nFft),
MikamiUitOpen 0:9470a174c910 13 yFft_(new Complex[nFft/2+1]) {}
MikamiUitOpen 0:9470a174c910 14
MikamiUitOpen 0:9470a174c910 15 FftAnalyzer::~FftAnalyzer()
MikamiUitOpen 0:9470a174c910 16 {
MikamiUitOpen 0:9470a174c910 17 delete[] yFft_;
MikamiUitOpen 0:9470a174c910 18 }
MikamiUitOpen 0:9470a174c910 19
MikamiUitOpen 0:9470a174c910 20 void FftAnalyzer::Analyze(const float xn[], float yn[])
MikamiUitOpen 0:9470a174c910 21 {
MikamiUitOpen 0:9470a174c910 22 fft_.Execute(xn, yFft_); // Execute FFT
MikamiUitOpen 0:9470a174c910 23
MikamiUitOpen 0:9470a174c910 24 // Translate to dB
MikamiUitOpen 0:9470a174c910 25 for (int n=0; n<=N_FFT_/2; n++)
MikamiUitOpen 0:9470a174c910 26 yn[n] = 10.0f*log10f(Norm(yFft_[n]));
MikamiUitOpen 0:9470a174c910 27 }
MikamiUitOpen 0:9470a174c910 28 }