/*****************************************************************************
-** FILE IDENTIFICATION
+** File IDENTIFICATION
**
** Name: filter.cpp
** Purpose: Routines for signal-procesing filters
** This is part of the CTSim program
** Copyright (C) 1983-2000 Kevin Rosenberg
**
-** $Id: filter.cpp,v 1.8 2000/07/04 18:33:35 kevin Exp $
+** $Id: filter.cpp,v 1.11 2000/07/05 17:24:33 kevin Exp $
**
** This program is free software; you can redistribute it and/or modify
** it under the terms of the GNU General Public License (version 2) as
m_fail = true;
return;
}
+ m_traceLevel = TRACE_NONE;
m_nameFilter = convertFilterIDToName (m_idFilter);
m_nameDomain = convertDomainIDToName (m_idDomain);
m_nameFilterMethod = convertFilterMethodIDToName (m_idFilterMethod);
m_vecFourierSinTable[i] = sin (angleIncrement * i);
}
m_nFilterPoints = m_nSignalPoints;
- m_filterMin = 0;
- m_filterMax = m_nSignalPoints * m_signalInc;
- m_filterInc = (m_filterMax - m_filterMin) / (m_nFilterPoints - 1);
+ m_filterMin = -1. / (2 * m_signalInc);
+ m_filterMax = 1. / (2 * m_signalInc);
+ m_filterInc = (m_filterMax - m_filterMin) / m_nFilterPoints;
m_vecFilter = new double [m_nFilterPoints];
int halfFilter = m_nFilterPoints / 2;
for (int i = 0; i < halfFilter; i++)
m_vecFilter[i] = static_cast<double>(i) / (halfFilter - 1) / (2 * m_signalInc);
for (int i = 0; i < halfFilter; i++)
- m_vecFilter[m_nFilterPoints - i - 1] = static_cast<double>(i) / (halfFilter - 1) / (2 * m_signalInc);
+ m_vecFilter[m_nFilterPoints - i - 1] = static_cast<double>(i+1) / (halfFilter - 1) / (2 * m_signalInc);
if (halfFilter % 2) // odd
- m_vecFilter[halfFilter] = 1;
+ m_vecFilter[halfFilter] = 1 / (2 * m_signalInc);
} else if (m_idFilterMethod == FILTER_METHOD_FFT || m_idFilterMethod == FILTER_METHOD_FFT_ZEROPAD_2 || m_idFilterMethod == FILTER_METHOD_FFT_ZEROPAD_4) {
m_nFilterPoints = m_nSignalPoints;
if (m_idFilterMethod == FILTER_METHOD_FFT_ZEROPAD_2 || m_idFilterMethod == FILTER_METHOD_FFT_ZEROPAD_4) {
m_nFilterPoints = 1 << nextPowerOf2;
cout << "nFilterPoints = " << m_nFilterPoints << endl;
}
- m_filterMin = 0;
- m_filterMax = m_nSignalPoints * m_signalInc;
- m_filterInc = (m_filterMax - m_filterMin) / (m_nFilterPoints - 1);
+ m_filterMin = -1. / (2 * m_signalInc);
+ m_filterMax = 1. / (2 * m_signalInc);
+ m_filterInc = (m_filterMax - m_filterMin) / m_nFilterPoints;
m_vecFilter = new double [m_nFilterPoints];
int halfFilter = m_nFilterPoints / 2;
for (int i = 0; i < halfFilter; i++)
- m_vecFilter[i] = static_cast<double>(i) / (halfFilter - 1) / (2 * m_signalInc);
+ m_vecFilter[i] = static_cast<double>(i) / (halfFilter - 1) / (2 * m_signalInc) / m_nSignalPoints;
for (int i = 0; i < halfFilter; i++)
- m_vecFilter[m_nFilterPoints - i - 1] = static_cast<double>(i) / (halfFilter - 1) / (2 * m_signalInc);
+ m_vecFilter[m_nFilterPoints - i - 1] = static_cast<double>(i+1) / (halfFilter - 1) / (2 * m_signalInc) / m_nSignalPoints;
if (halfFilter % 2) // odd
- m_vecFilter[halfFilter] = 1;
+ m_vecFilter[halfFilter] = 1 / (2 * m_signalInc) / m_nSignalPoints;
#if HAVE_FFTW
m_planForward = fftw_create_plan (m_nFilterPoints, FFTW_FORWARD, FFTW_ESTIMATE);
finiteFourierTransform (input, fftSignal, m_nSignalPoints, -1);
dotProduct (m_vecFilter, fftSignal, filteredSignal, m_nSignalPoints);
finiteFourierTransform (filteredSignal, complexOutput, m_nSignalPoints, 1);
- for (int i = 0; i < m_nSignalPoints; i++) {
- output[i] = abs( complexOutput[i] );
- }
+ for (int i = 0; i < m_nSignalPoints; i++)
+ output[i] = complexOutput[i].real();
} else if (m_idFilterMethod == FILTER_METHOD_FFT || FILTER_METHOD_FFT_ZEROPAD_2 || FILTER_METHOD_FFT_ZEROPAD_4) {
fftw_complex in[m_nFilterPoints], out[m_nFilterPoints];
for (int i = 0; i < m_nSignalPoints; i++) {
}
fftw_one(m_planForward, in, out);
for (int i = 0; i < m_nFilterPoints; i++) {
- out[i].re = m_vecFilter[i] * out[i].re / m_nSignalPoints;
- out[i].im = m_vecFilter[i] * out[i].im / m_nSignalPoints;
+ out[i].re = m_vecFilter[i] * out[i].re;
+ out[i].im = m_vecFilter[i] * out[i].im;
}
fftw_one(m_planBackward, out, in);
for (int i = 0; i < m_nSignalPoints; i++)
- output[i] = sqrt (in[i].re * in[i].re + in[i].im * in[i].im);
+ output[i] = in[i].re;
}
}