1 /*****************************************************************************
5 ** Purpose: Signal filter header file
6 ** Programmer: Kevin Rosenberg
7 ** Date Started: June 2000
9 ** This is part of the CTSim program
10 ** Copyright (C) 1983-2000 Kevin Rosenberg
12 ** $Id: filter.h,v 1.14 2000/07/19 04:33:27 kevin Exp $
14 ** This program is free software; you can redistribute it and/or modify
15 ** it under the terms of the GNU General Public License (version 2) as
16 ** published by the Free Software Foundation.
18 ** This program is distributed in the hope that it will be useful,
19 ** but WITHOUT ANY WARRANTY; without even the implied warranty of
20 ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 ** GNU General Public License for more details.
23 ** You should have received a copy of the GNU General Public License
24 ** along with this program; if not, write to the Free Software
25 ** Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
26 ******************************************************************************/
53 FILTER_ABS_BANDLIMIT, // filter times |x|
61 FILTER_METHOD_INVALID,
62 FILTER_METHOD_CONVOLUTION,
63 FILTER_METHOD_FOURIER,
64 FILTER_METHOD_FOURIER_TABLE,
78 static const char FILTER_ABS_BANDLIMIT_STR[]= "abs_bandlimit";
79 static const char FILTER_ABS_SINC_STR[]= "abs_sinc";
80 static const char FILTER_ABS_COS_STR[]= "abs_cos";
81 static const char FILTER_ABS_HAMMING_STR[]= "abs_hamming";
82 static const char FILTER_SHEPP_STR[]= "shepp";
83 static const char FILTER_BANDLIMIT_STR[]= "bandlimit";
84 static const char FILTER_SINC_STR[]= "sinc";
85 static const char FILTER_COS_STR[]= "cos";
86 static const char FILTER_HAMMING_STR[]= "hamming";
87 static const char FILTER_TRIANGLE_STR[]= "triangle";
89 static const char FILTER_METHOD_CONVOLUTION_STR[]= "convolution";
90 static const char FILTER_METHOD_FOURIER_STR[]= "fourier";
91 static const char FILTER_METHOD_FOURIER_TABLE_STR[]="fourier_table";
92 static const char FILTER_METHOD_FFT_STR[]= "fft";
94 static const char FILTER_METHOD_FFTW_STR[]= "fftw";
95 static const char FILTER_METHOD_RFFTW_STR[]= "rfftw";
98 static const char DOMAIN_FREQUENCY_STR[]="frequency";
99 static const char DOMAIN_SPATIAL_STR[]="spatial";
102 SignalFilter (const char* filterName, const char* filterMethodName,double bw, double signalIncrement, int n, double param, const char* domainName, const int zeropad = 0, const int preinterpolationFactor = 1);
104 SignalFilter (const FilterID filt_type, FilterMethodID filterMethodID, double bw, double signalIncrement, int n, double param, const DomainID domain, const int zeropad = 0, const int preinterpolationFactor = 1);
106 SignalFilter (const char* filterName, const char* domainName, double bw, double param);
108 ~SignalFilter (void);
110 double* getFilter (void) const
111 { return m_vecFilter; }
113 int getNFilterPoints (void) const
114 { return m_nFilterPoints; }
116 double convolve (const double f[], const double dx, const int n, const int np) const;
118 double convolve (const float f[], const double dx, const int n, const int np) const;
120 void filterSignal (const double input[], double output[]) const;
121 void filterSignal (const float input[], double output[]) const;
123 static void finiteFourierTransform (const double input[], complex<double> output[], const int n, const int direction);
124 static void finiteFourierTransform (const complex<double> input[], complex<double> output[], const int n, const int direction);
125 static void finiteFourierTransform (const complex<double> input[], double output[], const int n, const int direction);
127 void finiteFourierTransform (const double input[], complex<double> output[], const int direction) const;
128 void finiteFourierTransform (const complex<double> input[], complex<double> output[], const int direction) const;
129 void finiteFourierTransform (const complex<double> input[], double output[], const int direction) const;
131 void setTraceLevel (int traceLevel) {m_traceLevel = traceLevel; }
133 bool fail(void) const {return m_fail;}
134 const string& failMessage(void) const {return m_failMessage;}
136 const string& nameFilter(void) const { return m_nameFilter;}
137 const string& nameDomain(void) const { return m_nameDomain;}
138 const FilterID idFilter(void) const { return m_idFilter;}
139 const DomainID idDomain(void) const { return m_idDomain;}
140 const double getFilterMin(void) const {return m_filterMin;}
141 const double getFilterMax(void) const {return m_filterMax;}
142 const double getFilterIncrement(void) const {return m_filterInc;}
144 double response (double x);
146 static double spatialResponse (FilterID fType, double bw, double x, double param);
148 static double frequencyResponse (FilterID fType, double bw, double u, double param);
150 static double spatialResponseAnalytic (FilterID fType, double bw, double x, double param);
152 static double spatialResponseCalc (FilterID fType, double bw, double x, double param, int nIntegral);
154 static void setNumIntegral(int nIntegral) {N_INTEGRAL = nIntegral;}
165 double* m_vecFourierCosTable;
166 double* m_vecFourierSinTable;
167 complex<double>* m_complexVecFilter;
169 fftw_real* m_vecRealFftInput, *m_vecRealFftSignal;
170 rfftw_plan m_realPlanForward, m_realPlanBackward;
171 fftw_complex* m_vecComplexFftInput, *m_vecComplexFftSignal;
172 fftw_plan m_complexPlanForward, m_complexPlanBackward;
176 string m_failMessage;
178 string m_nameFilterMethod;
181 FilterMethodID m_idFilterMethod;
183 double m_filterParam;
187 int m_preinterpolationFactor;
189 static int N_INTEGRAL;
191 static const bool haveAnalyticSpatial (const FilterID filterID);
192 static const FilterID convertFilterNameToID (const char* filterName);
193 static const char* convertFilterIDToName (const FilterID filterID);
194 static const FilterMethodID convertFilterMethodNameToID (const char* filterMethodName);
195 static const char* convertFilterMethodIDToName (const FilterMethodID filterMethodID);
196 static const DomainID convertDomainNameToID (const char* domainName);
197 static const char* convertDomainIDToName (const DomainID domainID);
199 void init (const FilterID filt_type, const FilterMethodID filterMethod, double bw, double signalIncrement, int n, double param, const DomainID domain, const int zeropad, const int preInterpScale);
201 double spatialResponseCalc (double x, double param) const;
203 double spatialResponseAnalytic (double x, double param) const;
205 double frequencyResponse (double u, double param) const;
207 static double sinc (double x, double mult)
208 { return (fabs(x) > F_EPSILON ? (sin (x * mult) / x) : 1.0); }
210 static double integral_abscos (double u, double w);