** This is part of the CTSim program
** Copyright (C) 1983-2000 Kevin Rosenberg
**
-** $Id: filter.cpp,v 1.15 2000/07/07 15:30:59 kevin Exp $
+** $Id: filter.cpp,v 1.17 2000/07/13 07:03:21 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
#include "ct.h"
+int SignalFilter::N_INTEGRAL=500; //static member
+
/* NAME
* SignalFilter::SignalFilter Construct a signal
*
* int nSignalPoints Number of points in signal
* double param General input parameter to filters
* int domain FREQUENCY or SPATIAL domain wanted
- * int numint Number if intervals for calculating discrete inverse fourier xform
- * for spatial domain filters. For ANALYTIC solutions, use numint = 0
*/
-SignalFilter::SignalFilter (const char* filterName, const char* filterMethodName, double bw, double signalIncrement, int nSignalPoints, double param, const char* domainName, int zeropad = 0, int numIntegral = 0)
+SignalFilter::SignalFilter (const char* filterName, const char* filterMethodName, double bw, double signalIncrement, int nSignalPoints, double param, const char* domainName, int zeropad = 0, int preinterpolationFactor = 1)
{
m_vecFilter = NULL;
m_vecFourierCosTable = NULL;
m_failMessage += domainName;
return;
}
- init (m_idFilter, m_idFilterMethod, bw, signalIncrement, nSignalPoints, param, m_idDomain, zeropad, numIntegral);
+ init (m_idFilter, m_idFilterMethod, bw, signalIncrement, nSignalPoints, param, m_idDomain, zeropad, preinterpolationFactor);
}
-SignalFilter::SignalFilter (const FilterID filterID, const FilterMethodID filterMethodID, double bw, double signalIncrement, int nSignalPoints, double param, const DomainID domainID, int zeropad = 0, int numIntegral = 0)
+SignalFilter::SignalFilter (const FilterID filterID, const FilterMethodID filterMethodID, double bw, double signalIncrement, int nSignalPoints, double param, const DomainID domainID, int zeropad = 0, int preinterpolationFactor = 1)
{
- init (filterID, filterMethodID, bw, signalIncrement, nSignalPoints, param, domainID, zeropad, numIntegral);
+ init (filterID, filterMethodID, bw, signalIncrement, nSignalPoints, param, domainID, zeropad, preinterpolationFactor);
}
-SignalFilter::SignalFilter (const char* filterName, const char* domainName, double bw, double param, int numIntegral = 0)
+SignalFilter::SignalFilter (const char* filterName, const char* domainName, double bw, double param)
{
m_bw = bw;
m_nSignalPoints = 0;
m_vecFourierCosTable = NULL;
m_vecFourierSinTable = NULL;
m_filterParam = param;
- m_numIntegral = numIntegral;
m_idFilter = convertFilterNameToID (filterName);
if (m_idFilter == FILTER_INVALID) {
m_fail = true;
}
void
-SignalFilter::init (const FilterID filterID, const FilterMethodID filterMethodID, double bw, double signalIncrement, int nSignalPoints, double param, const DomainID domainID, int zeropad, int numint)
+SignalFilter::init (const FilterID filterID, const FilterMethodID filterMethodID, double bw, double signalIncrement, int nSignalPoints, double filterParam, const DomainID domainID, int zeropad, int preinterpolationFactor)
{
m_bw = bw;
m_idFilter = filterID;
m_fail = false;
m_nSignalPoints = nSignalPoints;
m_signalInc = signalIncrement;
- m_filterParam = param;
+ m_filterParam = filterParam;
m_zeropad = zeropad;
+ m_preinterpolationFactor = preinterpolationFactor;
m_vecFourierCosTable = NULL;
m_vecFourierSinTable = NULL;
m_nFilterPoints = 1 << nextPowerOf2;
cout << "nFilterPoints = " << m_nFilterPoints << endl;
}
+ m_nOutputPoints = m_nFilterPoints * m_preinterpolationFactor;
m_filterMin = -1. / (2 * m_signalInc);
m_filterMax = 1. / (2 * m_signalInc);
m_filterInc = (m_filterMax - m_filterMin) / m_nFilterPoints;
// precalculate sin and cosine tables for fourier transform
if (m_idFilterMethod == FILTER_METHOD_FOURIER_TABLE) {
- int nFourier = m_nFilterPoints * m_nFilterPoints + 1;
- double angleIncrement = (2. * PI) / m_nFilterPoints;
- m_vecFourierCosTable = new double[ nFourier ];
- m_vecFourierSinTable = new double[ nFourier ];
- double angle = 0;
- for (int i = 0; i < nFourier; i++) {
- m_vecFourierCosTable[i] = cos (angle);
- m_vecFourierSinTable[i] = sin (angle);
- angle += angleIncrement;
- }
+ int nFourier = max(m_nFilterPoints,m_nOutputPoints) * max(m_nFilterPoints, m_nOutputPoints) + 1;
+ double angleIncrement = (2. * PI) / m_nFilterPoints;
+ m_vecFourierCosTable = new double[ nFourier ];
+ m_vecFourierSinTable = new double[ nFourier ];
+ double angle = 0;
+ for (int i = 0; i < nFourier; i++) {
+ m_vecFourierCosTable[i] = cos (angle);
+ m_vecFourierSinTable[i] = sin (angle);
+ angle += angleIncrement;
+ }
}
#if HAVE_FFTW
}
if (m_idFilterMethod == FILTER_METHOD_RFFTW) {
- m_complexPlanForward = m_complexPlanBackward = NULL;
m_realPlanForward = rfftw_create_plan (m_nFilterPoints, FFTW_REAL_TO_COMPLEX, FFTW_ESTIMATE);
- m_realPlanBackward = rfftw_create_plan (m_nFilterPoints, FFTW_COMPLEX_TO_REAL, FFTW_ESTIMATE);
+ m_realPlanBackward = rfftw_create_plan (m_nOutputPoints, FFTW_COMPLEX_TO_REAL, FFTW_ESTIMATE);
m_vecRealFftInput = new fftw_real [ m_nFilterPoints ];
+ m_vecRealFftSignal = new fftw_real [ m_nOutputPoints ];
for (int i = 0; i < m_nFilterPoints; i++)
m_vecRealFftInput[i] = 0;
} else if (m_idFilterMethod == FILTER_METHOD_FFTW) {
- m_realPlanForward = m_realPlanBackward = NULL;
- m_complexPlanForward = fftw_create_plan (m_nFilterPoints, FFTW_FORWARD, FFTW_ESTIMATE);
- m_complexPlanBackward = fftw_create_plan (m_nFilterPoints, FFTW_BACKWARD, FFTW_ESTIMATE);
+ m_complexPlanForward = fftw_create_plan (m_nFilterPoints, FFTW_FORWARD, FFTW_ESTIMATE);
+ m_complexPlanBackward = fftw_create_plan (m_nOutputPoints, FFTW_BACKWARD, FFTW_ESTIMATE);
m_vecComplexFftInput = new fftw_complex [ m_nFilterPoints ];
+ m_vecComplexFftSignal = new fftw_complex [ m_nOutputPoints ];
for (int i = 0; i < m_nFilterPoints; i++)
m_vecComplexFftInput[i].re = m_vecComplexFftInput[i].im = 0;
+ for (int i = 0; i < m_nOutputPoints; i++)
+ m_vecComplexFftSignal[i].re = m_vecComplexFftSignal[i].im = 0;
}
#endif
m_filterMin = -m_signalInc * (m_nSignalPoints - 1);
m_filterMax = m_signalInc * (m_nSignalPoints - 1);
m_filterInc = (m_filterMax - m_filterMin) / (m_nFilterPoints - 1);
- m_numIntegral = numint;
m_vecFilter = new double[ m_nFilterPoints ];
if (m_idFilter == FILTER_SHEPP) {
double x;
int i;
for (x = m_filterMin, i = 0; i < m_nFilterPoints; x += m_filterInc, i++)
- m_vecFilter[i] = frequencyResponse (x, param);
+ m_vecFilter[i] = frequencyResponse (x, m_filterParam);
} else if (m_idDomain == DOMAIN_SPATIAL) {
double x;
int i;
for (x = m_filterMin, i = 0; i < m_nFilterPoints; x += m_filterInc, i++)
- if (numint == 0)
- m_vecFilter[i] = spatialResponseAnalytic (x, param);
+ if (haveAnalyticSpatial(m_idFilter))
+ m_vecFilter[i] = spatialResponseAnalytic (x, m_filterParam);
else
- m_vecFilter[i] = spatialResponseCalc (x, param, numint);
+ m_vecFilter[i] = spatialResponseCalc (x, m_filterParam);
} else {
m_failMessage = "Illegal domain name ";
m_failMessage += m_idDomain;
fftw_destroy_plan(m_complexPlanForward);
fftw_destroy_plan(m_complexPlanBackward);
delete [] m_vecComplexFftInput;
+ delete [] m_vecComplexFftSignal;
}
if (m_idFilterMethod == FILTER_METHOD_RFFTW) {
rfftw_destroy_plan(m_realPlanForward);
rfftw_destroy_plan(m_realPlanBackward);
delete [] m_vecRealFftInput;
+ delete [] m_vecRealFftSignal;
}
#endif
}
return (name);
}
-
void
SignalFilter::filterSignal (const float input[], double output[]) const
{
for (int i = 0; i < m_nSignalPoints; i++)
m_vecRealFftInput[i] = input[i];
- fftw_real out[m_nFilterPoints];
- rfftw_one (m_realPlanForward, m_vecRealFftInput, out);
- for (int i = 0; i < m_nFilterPoints; i++) {
- out[i] *= m_vecFilter[i];
- }
- fftw_real outFiltered[m_nFilterPoints];
- rfftw_one(m_realPlanBackward, out, outFiltered);
- for (int i = 0; i < m_nSignalPoints; i++)
- output[i] = outFiltered[i];
+ fftw_real fftOutput [ m_nFilterPoints ];
+ rfftw_one (m_realPlanForward, m_vecRealFftInput, fftOutput);
+ for (int i = 0; i < m_nFilterPoints; i++)
+ m_vecRealFftSignal[i] = m_vecFilter[i] * fftOutput[i];
+ for (int i = m_nFilterPoints; i < m_nOutputPoints; i++)
+ m_vecRealFftSignal[i] = 0;
+
+ fftw_real ifftOutput [ m_nOutputPoints ];
+ rfftw_one(m_realPlanBackward, m_vecRealFftSignal, ifftOutput);
+ for (int i = 0; i < m_nSignalPoints * m_preinterpolationFactor; i++)
+ output[i] = ifftOutput[i];
} else if (m_idFilterMethod == FILTER_METHOD_FFTW) {
for (int i = 0; i < m_nSignalPoints; i++)
m_vecComplexFftInput[i].re = input[i];
- fftw_complex out[m_nFilterPoints];
- fftw_one(m_complexPlanForward, m_vecComplexFftInput, out);
+ fftw_complex fftOutput [ m_nFilterPoints ];
+ fftw_one(m_complexPlanForward, m_vecComplexFftInput, fftOutput);
for (int i = 0; i < m_nFilterPoints; i++) {
- out[i].re *= m_vecFilter[i];
- out[i].im *= m_vecFilter[i];
+ m_vecComplexFftSignal[i].re = m_vecFilter[i] * fftOutput[i].re;
+ m_vecComplexFftSignal[i].im = m_vecFilter[i] * fftOutput[i].im;
}
- fftw_complex outFiltered[m_nFilterPoints];
- fftw_one(m_complexPlanBackward, out, outFiltered);
- for (int i = 0; i < m_nSignalPoints; i++)
- output[i] = outFiltered[i].re;
+ fftw_complex ifftOutput [ m_nOutputPoints ];
+ fftw_one(m_complexPlanBackward, m_vecComplexFftSignal, ifftOutput);
+ for (int i = 0; i < m_nSignalPoints * m_preinterpolationFactor; i++)
+ output[i] = ifftOutput[i].re;
}
#endif
}
double response = 0;
if (m_idDomain == DOMAIN_SPATIAL)
- response = spatialResponse (m_idFilter, m_bw, x, m_filterParam, m_numIntegral);
+ response = spatialResponse (m_idFilter, m_bw, x, m_filterParam);
else if (m_idDomain == DOMAIN_FREQUENCY)
response = frequencyResponse (m_idFilter, m_bw, x, m_filterParam);
double
-SignalFilter::spatialResponse (FilterID filterID, double bw, double x, double param, int nIntegral = 0)
+SignalFilter::spatialResponse (FilterID filterID, double bw, double x, double param)
{
- if (nIntegral == 0)
+ if (haveAnalyticSpatial(filterID))
return spatialResponseAnalytic (filterID, bw, x, param);
else
- return spatialResponseCalc (filterID, bw, x, param, nIntegral);
+ return spatialResponseCalc (filterID, bw, x, param, N_INTEGRAL);
}
/* NAME
*/
double
-SignalFilter::spatialResponseCalc (double x, double param, int nIntegral) const
+SignalFilter::spatialResponseCalc (double x, double param) const
{
- return (spatialResponseCalc (m_idFilter, m_bw, x, param, nIntegral));
+ return (spatialResponseCalc (m_idFilter, m_bw, x, param, N_INTEGRAL));
}
double
return spatialResponseAnalytic (m_idFilter, m_bw, x, param);
}
+const bool
+SignalFilter::haveAnalyticSpatial (FilterID filterID)
+{
+ bool haveAnalytic = false;
+
+ switch (filterID) {
+ case FILTER_BANDLIMIT:
+ case FILTER_TRIANGLE:
+ case FILTER_COSINE:
+ case FILTER_G_HAMMING:
+ case FILTER_ABS_BANDLIMIT:
+ case FILTER_ABS_COSINE:
+ case FILTER_ABS_G_HAMMING:
+ case FILTER_SHEPP:
+ case FILTER_SINC:
+ haveAnalytic = true;
+ break;
+ default:
+ break;
+ }
+
+ return (haveAnalytic);
+}
+
double
SignalFilter::spatialResponseAnalytic (FilterID filterID, double bw, double x, double param)
{
projects / ctsim.git / blobdiff