不韋 呂 / Mbed 2 deprecated F446_Spectrogram

Realtime sound spectrogram using FFT or linear prediction. Spectrogram is displayed on the display of PC. リアルタイム･スペクトログラム．解析の手法：FFT，線形予測法．スペクトログラムは PC のディスプレー装置に表示される．PC 側のプログラム：F446_Spectrogram.

Dependencies:   Array_Matrix mbed SerialTxRxIntr F446_AD_DA UIT_FFT_Real

MySpectrogram/FFT_Analyzer.cpp@7:5ba884060d3b, 2019-11-24 (annotated)

Committer:
MikamiUitOpen
Date:
Sun Nov 24 11:14:01 2019 +0000
Revision:
7:5ba884060d3b
Parent:
6:c38ec7939609 
8

Who changed what in which revision?

UserRevisionLine numberNew contents of line
MikamiUitOpen 0:a539141b9dec 1 //-------------------------------------------------------
MikamiUitOpen 0:a539141b9dec 2 // Class for spectrum analysis using FFT
MikamiUitOpen 0:a539141b9dec 3 //
MikamiUitOpen 7:5ba884060d3b 4 // 2018/11/24, Copyright (c) 2018 MIKAMI, Naoki
MikamiUitOpen 0:a539141b9dec 5 //-------------------------------------------------------
MikamiUitOpen 0:a539141b9dec 6
MikamiUitOpen 0:a539141b9dec 7 #include "FFT_Analyzer.hpp"
MikamiUitOpen 0:a539141b9dec 8
MikamiUitOpen 0:a539141b9dec 9 namespace Mikami
MikamiUitOpen 0:a539141b9dec 10 {
MikamiUitOpen 0:a539141b9dec 11 FftAnalyzer::FftAnalyzer(int nData, int nFft)
MikamiUitOpen 0:a539141b9dec 12 : AnalyzerBase(nData, nFft, nFft),
MikamiUitOpen 0:a539141b9dec 13 yFft_(nFft/2+1) {}
MikamiUitOpen 0:a539141b9dec 14
MikamiUitOpen 0:a539141b9dec 15 void FftAnalyzer::Analyze(const float xn[], float yn[])
MikamiUitOpen 0:a539141b9dec 16 {
MikamiUitOpen 0:a539141b9dec 17 fft_.Execute(xn, yFft_); // Execute FFT
MikamiUitOpen 0:a539141b9dec 18
MikamiUitOpen 0:a539141b9dec 19 // Translate to dB
MikamiUitOpen 7:5ba884060d3b 20 for (int n=0; n<=N_FFT_/2; n++)
MikamiUitOpen 0:a539141b9dec 21 yn[n] = 10.0f*log10f(Norm(yFft_[n]));
MikamiUitOpen 0:a539141b9dec 22 }
MikamiUitOpen 0:a539141b9dec 23 }