digital audio mod11 / Mbed 2 deprecated fftimplement

oldexamplecode

Dependencies:   mbed

DFT.h@0:6863633bf8a4, 2017-03-24 (annotated)

Committer:
rik
Date:
Fri Mar 24 11:22:30 2017 +0000
Revision:
0:6863633bf8a4
oldexamplecode;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
rik 0:6863633bf8a4 1
rik 0:6863633bf8a4 2 // This file first preprocesses a 1024 long data array by:
rik 0:6863633bf8a4 3 // - Calculating and substracting the mean
rik 0:6863633bf8a4 4 // - Applying a hanning window
rik 0:6863633bf8a4 5 // - Re-indexing the array
rik 0:6863633bf8a4 6 // It then applies a radix-2 Cooley Tukey FFT to create a DFT of the original signal
rik 0:6863633bf8a4 7
rik 0:6863633bf8a4 8 #pragma once
rik 0:6863633bf8a4 9 #ifndef _DFT_H_
rik 0:6863633bf8a4 10 #define _DFT_H_
rik 0:6863633bf8a4 11
rik 0:6863633bf8a4 12 #include <string.h> // Only for memcpy
rik 0:6863633bf8a4 13 #include "LookupTables.h"
rik 0:6863633bf8a4 14 #include "complexmath.h"
rik 0:6863633bf8a4 15
rik 0:6863633bf8a4 16 // Preprocesses the data array and performs a dft on it, ARRAY MUST BE 1024 LONG
rik 0:6863633bf8a4 17 void performFFT(float* datam, int datalength);
rik 0:6863633bf8a4 18
rik 0:6863633bf8a4 19 // Performs a radix-2 cooley tukey FFT on the data array
rik 0:6863633bf8a4 20 void cooleyTukeyRadix2(float* data, int datalength);
rik 0:6863633bf8a4 21
rik 0:6863633bf8a4 22 // Calculates and subtracts the signal mean
rik 0:6863633bf8a4 23 void subMean(float* data, int datalength);
rik 0:6863633bf8a4 24
rik 0:6863633bf8a4 25 // Reindexes the array in preperation of the FFT
rik 0:6863633bf8a4 26 void reindexData(float* data, int datalength);
rik 0:6863633bf8a4 27
rik 0:6863633bf8a4 28 // Removes the DC component and null everything above the nyquist frequency
rik 0:6863633bf8a4 29 void afterProcessing(float* data, int datalength);
rik 0:6863633bf8a4 30
rik 0:6863633bf8a4 31 // Filter a frequency and its multiples
rik 0:6863633bf8a4 32 void filterfreq(int frequency, float* data, int datalength);
rik 0:6863633bf8a4 33
rik 0:6863633bf8a4 34 // Calculate total magnitude, frequency magnitude component integrating module (FMCIM)
rik 0:6863633bf8a4 35 int calcPSD(float* data, int datalength);
rik 0:6863633bf8a4 36
rik 0:6863633bf8a4 37 #endif