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70 lines
1.4 KiB
70 lines
1.4 KiB
15 years ago
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/*
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a FFT class
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Copyright (C) 1998 Martin Vogt;Philip VanBaren
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation.
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For more information look at the file COPYRIGHT in this package
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*/
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#ifndef __REALFFT_H
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#define __REALFFT_H
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#include <math.h>
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#include <stdlib.h>
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#include <stdio.h>
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/**
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<pre>
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* Program: REALFFTF.C
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* Author: Philip VanBaren
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* Date: 2 September 1993
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*
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* Description: These routines perform an FFT on real data.
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* On a 486/33 compiled using Borland C++ 3.1 with full
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* speed optimization and a small memory model, a 1024 point
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* FFT takes about 16ms.
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* This code is for floating point data.
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*
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* Note: Output is BIT-REVERSED! so you must use the BitReversed to
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* get legible output, (i.e. Real_i = buffer[ BitReversed[i] ]
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* Imag_i = buffer[ BitReversed[i]+1 ] )
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* Input is in normal order.
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</pre>
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*/
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class RealFFT {
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int* BitReversed;
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short* SinTable;
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int Points;
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public:
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RealFFT(int fftlen);
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~RealFFT();
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void fft(short* buffer);
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int* getBitReversed();
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private:
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short *A,*B;
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short *sptr;
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short *endptr1,*endptr2;
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int *br1,*br2;
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long HRplus,HRminus,HIplus,HIminus;
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};
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#endif
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