X-Git-Url: http://git.kpe.io/?a=blobdiff_plain;f=libctsim%2Ffilter.cpp;h=0a24996805bba3a24f48bdb83c1bd1900c9b5e04;hb=a2a9671aff06827cec6d6b80234b90128d337e40;hp=640bfb2d6b84783904d5e42034052ee4cabc7845;hpb=b847a34057751df3a3f4e2bf795227a13ef4788c;p=ctsim.git diff --git a/libctsim/filter.cpp b/libctsim/filter.cpp index 640bfb2..0a24996 100644 --- a/libctsim/filter.cpp +++ b/libctsim/filter.cpp @@ -9,7 +9,7 @@ ** This is part of the CTSim program ** Copyright (C) 1983-2000 Kevin Rosenberg ** -** $Id: filter.cpp,v 1.10 2000/07/05 01:34:46 kevin Exp $ +** $Id: filter.cpp,v 1.13 2000/07/06 08:30:30 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 @@ -44,11 +44,12 @@ * 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 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 numIntegral = 0) { m_vecFilter = NULL; m_vecFourierCosTable = NULL; m_vecFourierSinTable = NULL; + m_vecFftInput = NULL; m_idFilter = convertFilterNameToID (filterName); if (m_idFilter == FILTER_INVALID) { m_fail = true; @@ -70,12 +71,12 @@ SignalFilter::SignalFilter (const char* filterName, const char* filterMethodName m_failMessage += domainName; return; } - init (m_idFilter, m_idFilterMethod, bw, signalIncrement, nSignalPoints, param, m_idDomain, numIntegral); + init (m_idFilter, m_idFilterMethod, bw, signalIncrement, nSignalPoints, param, m_idDomain, zeropad, numIntegral); } -SignalFilter::SignalFilter (const FilterID filterID, const FilterMethodID filterMethodID, double bw, double signalIncrement, int nSignalPoints, double param, const DomainID domainID, 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 numIntegral = 0) { - init (filterID, filterMethodID, bw, signalIncrement, nSignalPoints, param, domainID, numIntegral); + init (filterID, filterMethodID, bw, signalIncrement, nSignalPoints, param, domainID, zeropad, numIntegral); } SignalFilter::SignalFilter (const char* filterName, const char* domainName, double bw, double param, int numIntegral = 0) @@ -86,6 +87,7 @@ SignalFilter::SignalFilter (const char* filterName, const char* domainName, doub m_vecFilter = NULL; m_vecFourierCosTable = NULL; m_vecFourierSinTable = NULL; + m_vecFftInput = NULL; m_filterParam = param; m_numIntegral = numIntegral; m_idFilter = convertFilterNameToID (filterName); @@ -105,7 +107,7 @@ SignalFilter::SignalFilter (const char* filterName, const char* domainName, doub } void -SignalFilter::init (const FilterID filterID, const FilterMethodID filterMethodID, double bw, double signalIncrement, int nSignalPoints, double param, const DomainID domainID, int numint) +SignalFilter::init (const FilterID filterID, const FilterMethodID filterMethodID, double bw, double signalIncrement, int nSignalPoints, double param, const DomainID domainID, int zeropad, int numint) { m_bw = bw; m_idFilter = filterID; @@ -123,37 +125,24 @@ SignalFilter::init (const FilterID filterID, const FilterMethodID filterMethodID m_nSignalPoints = nSignalPoints; m_signalInc = signalIncrement; m_filterParam = param; - - if (m_idFilterMethod == FILTER_METHOD_FOURIER) { - int nFourier = m_nSignalPoints * m_nSignalPoints + 1; - double angleIncrement = (2. * PI) / m_nSignalPoints; - m_vecFourierCosTable = new double[ nFourier ]; - m_vecFourierSinTable = new double[ nFourier ]; - for (int i = 0; i < nFourier; i++) { - m_vecFourierCosTable[i] = cos (angleIncrement * i); - m_vecFourierSinTable[i] = sin (angleIncrement * i); - } - m_nFilterPoints = m_nSignalPoints; - 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(i) / (halfFilter - 1) / (2 * m_signalInc); - for (int i = 0; i < halfFilter; i++) - m_vecFilter[m_nFilterPoints - i - 1] = static_cast(i) / (halfFilter - 1) / (2 * m_signalInc); - if (halfFilter % 2) // odd - 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_zeropad = zeropad; + + m_vecFourierCosTable = NULL; + m_vecFourierSinTable = NULL; + m_vecFilter = NULL; + m_vecFftInput = NULL; + + if (m_idFilterMethod == FILTER_METHOD_FFT) + m_idFilterMethod = FILTER_METHOD_FFTW; + + if (m_idFilterMethod == FILTER_METHOD_FOURIER || m_idFilterMethod == FILTER_METHOD_FFT || m_idFilterMethod == FILTER_METHOD_FFTW) { m_nFilterPoints = m_nSignalPoints; - if (m_idFilterMethod == FILTER_METHOD_FFT_ZEROPAD_2 || m_idFilterMethod == FILTER_METHOD_FFT_ZEROPAD_4) { + if (m_zeropad > 0) { double logBase2 = log(m_nSignalPoints) / log(2); - int nextPowerOf2 = static_cast(floor(logBase2)) + 1; - if (m_idFilterMethod == FILTER_METHOD_FFT_ZEROPAD_4) - nextPowerOf2++; + int nextPowerOf2 = static_cast(floor(logBase2)); if (logBase2 != floor(logBase2)) nextPowerOf2++; + nextPowerOf2 += m_zeropad; m_nFilterPoints = 1 << nextPowerOf2; cout << "nFilterPoints = " << m_nFilterPoints << endl; } @@ -162,18 +151,38 @@ SignalFilter::init (const FilterID filterID, const FilterMethodID filterMethodID 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(i) / (halfFilter - 1) / (2 * m_signalInc); - for (int i = 0; i < halfFilter; i++) - m_vecFilter[m_nFilterPoints - i - 1] = static_cast(i) / (halfFilter - 1) / (2 * m_signalInc); - if (halfFilter % 2) // odd - m_vecFilter[halfFilter] = 1 / (2 * m_signalInc); + for (int i = 0; i <= halfFilter; i++) + m_vecFilter[i] = static_cast(i) / halfFilter/ (2. * m_signalInc); + for (int i = 1; i <= halfFilter; i++) + m_vecFilter[m_nFilterPoints - i] = static_cast(i) / halfFilter / (2. * m_signalInc); + } + + // precalculate sin and cosine tables for fourier transform + if (m_idFilterMethod == FILTER_METHOD_FOURIER) { + 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; + } + } #if HAVE_FFTW + if (m_idFilterMethod == FILTER_METHOD_FFTW) { + for (int i = 0; i < m_nFilterPoints; i++) //fftw uses unnormalized fft + m_vecFilter[i] /= m_nFilterPoints; + m_planForward = fftw_create_plan (m_nFilterPoints, FFTW_FORWARD, FFTW_ESTIMATE); m_planBackward = fftw_create_plan (m_nFilterPoints, FFTW_BACKWARD, FFTW_ESTIMATE); -#endif + m_vecFftInput = new fftw_complex [ m_nFilterPoints ]; + for (int i = 0; i < m_nFilterPoints; i++) + m_vecFftInput[i].re = m_vecFftInput[i].im = 0; } +#endif if (m_idFilterMethod == FILTER_METHOD_CONVOLUTION) { m_nFilterPoints = 2 * m_nSignalPoints - 1; @@ -215,11 +224,12 @@ SignalFilter::init (const FilterID filterID, const FilterMethodID filterMethodID SignalFilter::~SignalFilter (void) { - delete m_vecFilter; - delete m_vecFourierSinTable; - delete m_vecFourierCosTable; + delete [] m_vecFilter; + delete [] m_vecFourierSinTable; + delete [] m_vecFourierCosTable; + delete [] m_vecFftInput; #if HAVE_FFTW - if (m_idFilterMethod == FILTER_METHOD_FFT) { + if (m_idFilterMethod == FILTER_METHOD_FFTW) { fftw_destroy_plan(m_planForward); fftw_destroy_plan(m_planBackward); } @@ -296,12 +306,8 @@ SignalFilter::convertFilterMethodNameToID (const char* const filterMethodName) fmID = FILTER_METHOD_FOURIER; else if (strcasecmp (filterMethodName, FILTER_METHOD_FFT_STR) == 0) fmID = FILTER_METHOD_FFT; - else if (strcasecmp (filterMethodName, FILTER_METHOD_FFT_ZEROPAD_2_STR) == 0) - fmID = FILTER_METHOD_FFT_ZEROPAD_2; - else if (strcasecmp (filterMethodName, FILTER_METHOD_FFT_ZEROPAD_4_STR) == 0) - fmID = FILTER_METHOD_FFT_ZEROPAD_4; - else if (strcasecmp (filterMethodName, FILTER_METHOD_FFT_ZEROPAD_6_STR) == 0) - fmID = FILTER_METHOD_FFT_ZEROPAD_6; + else if (strcasecmp (filterMethodName, FILTER_METHOD_FFTW_STR) == 0) + fmID = FILTER_METHOD_FFTW; return (fmID); } @@ -317,12 +323,8 @@ SignalFilter::convertFilterMethodIDToName (const FilterMethodID fmID) return (FILTER_METHOD_FOURIER_STR); else if (fmID == FILTER_METHOD_FFT) return (FILTER_METHOD_FFT_STR); - else if (fmID == FILTER_METHOD_FFT_ZEROPAD_2) - return (FILTER_METHOD_FFT_ZEROPAD_2_STR); - else if (fmID == FILTER_METHOD_FFT_ZEROPAD_4) - return (FILTER_METHOD_FFT_ZEROPAD_4_STR); - else if (fmID == FILTER_METHOD_FFT_ZEROPAD_6) - return (FILTER_METHOD_FFT_ZEROPAD_6_STR); + else if (fmID == FILTER_METHOD_FFTW) + return (FILTER_METHOD_FFTW_STR); return (name); } @@ -361,67 +363,37 @@ SignalFilter::filterSignal (const float input[], double output[]) const for (int i = 0; i < m_nSignalPoints; i++) output[i] = convolve (input, m_signalInc, i, m_nSignalPoints); } else if (m_idFilterMethod == FILTER_METHOD_FOURIER) { - complex fftSignal[m_nSignalPoints]; - complex complexOutput[m_nSignalPoints]; - complex filteredSignal[m_nSignalPoints]; - finiteFourierTransform (input, fftSignal, m_nSignalPoints, -1); - if (m_traceLevel >= TRACE_PLOT) { - double test[m_nSignalPoints]; - for (int i = 0; i < m_nSignalPoints; i++) - test[i] = abs(fftSignal[i]); - ezplot_1d(test, m_nSignalPoints); - cio_kb_getc(); - } - dotProduct (m_vecFilter, fftSignal, filteredSignal, m_nSignalPoints); - if (m_traceLevel >= TRACE_PLOT) { - double test[m_nSignalPoints]; - for (int i = 0; i < m_nSignalPoints; i++) - test[i] = abs(filteredSignal[i]); - ezplot_1d(test, m_nSignalPoints); - cio_kb_getc(); - } - finiteFourierTransform (filteredSignal, complexOutput, m_nSignalPoints, 1); - for (int i = 0; i < m_nSignalPoints; i++) - output[i] = abs( complexOutput[i] ); - } 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++) { - in[i].re = input[i]; - in[i].im = 0; - } - for (int i = m_nSignalPoints; i < m_nFilterPoints; i++) { - in[i].re = in[i].im = 0; // ZeroPad - } - fftw_one(m_planForward, in, out); - if (m_traceLevel >= TRACE_PLOT) { - double test[m_nFilterPoints]; - for (int i = 0; i < m_nFilterPoints; i++) - test[i] = sqrt(out[i].re * out[i].re + out[i].im * out[i].im); - ezplot_1d(test, m_nFilterPoints); - cio_kb_getc(); - } - 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; - } - if (m_traceLevel >= TRACE_PLOT) { - double test[m_nFilterPoints]; - for (int i = 0; i < m_nFilterPoints; i++) - test[i] = sqrt(out[i].re * out[i].re + out[i].im * out[i].im); - ezplot_1d(test, m_nFilterPoints); - cio_kb_getc(); - } - fftw_one(m_planBackward, out, in); - if (m_traceLevel >= TRACE_PLOT) { - double test[m_nFilterPoints]; - for (int i = 0; i < m_nFilterPoints; i++) - test[i] = sqrt(in[i].re * in[i].re + in[i].im * in[i].im); - ezplot_1d(test, m_nFilterPoints); - cio_kb_getc(); - } + complex fftSignal[m_nFilterPoints]; + complex complexOutput[m_nFilterPoints]; + complex filteredSignal[m_nFilterPoints]; + double inputSignal[m_nFilterPoints]; + for (int i = 0; i < m_nSignalPoints; i++) + inputSignal[i] = input[i]; + for (int i = m_nSignalPoints; i < m_nFilterPoints; i++) + inputSignal[i] = 0; // zeropad + finiteFourierTransform (inputSignal, fftSignal, m_nFilterPoints, -1); + dotProduct (m_vecFilter, fftSignal, filteredSignal, m_nFilterPoints); + finiteFourierTransform (filteredSignal, complexOutput, m_nFilterPoints, 1); 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] = complexOutput[i].real(); + } +#if HAVE_FFTW + else if (m_idFilterMethod == FILTER_METHOD_FFTW) { + for (int i = 0; i < m_nSignalPoints; i++) + m_vecFftInput[i].re = input[i]; + + fftw_complex out[m_nFilterPoints]; + fftw_one(m_planForward, m_vecFftInput, out); + for (int i = 0; i < m_nFilterPoints; i++) { + out[i].re = m_vecFilter[i] * out[i].re; + out[i].im = m_vecFilter[i] * out[i].im; + } + fftw_complex outFiltered[m_nFilterPoints]; + fftw_one(m_planBackward, out, outFiltered); + for (int i = 0; i < m_nSignalPoints; i++) + output[i] = outFiltered[i].re; } +#endif } double @@ -751,19 +723,19 @@ for (int i = 0; i < np; i++) void -SignalFilter::finiteFourierTransform (const float input[], complex output[], const int n, int direction) +SignalFilter::finiteFourierTransform (const double input[], complex output[], const int n, int direction) { if (direction < 0) direction = -1; else direction = 1; - double angleIncrement = 2 * PI / n; + double angleIncrement = direction * 2 * PI / n; for (int i = 0; i < n; i++) { double sumReal = 0; double sumImag = 0; for (int j = 0; j < n; j++) { - double angle = i * j * angleIncrement * direction; + double angle = i * j * angleIncrement; sumReal += input[j] * cos(angle); sumImag += input[j] * sin(angle); } @@ -800,16 +772,16 @@ SignalFilter::finiteFourierTransform (const complex input[], complex output[], int direction) const +SignalFilter::finiteFourierTransform (const double input[], complex output[], int direction) const { if (direction < 0) direction = -1; else direction = 1; - for (int i = 0; i < m_nSignalPoints; i++) { + for (int i = 0; i < m_nFilterPoints; i++) { double sumReal = 0, sumImag = 0; - for (int j = 0; j < m_nSignalPoints; j++) { + for (int j = 0; j < m_nFilterPoints; j++) { int tableIndex = i * j; if (direction > 0) { sumReal += input[i] * m_vecFourierCosTable[tableIndex]; @@ -820,8 +792,8 @@ SignalFilter::finiteFourierTransform (const float input[], complex outpu } } if (direction < 0) { - sumReal /= m_nSignalPoints; - sumImag /= m_nSignalPoints; + sumReal /= m_nFilterPoints; + sumImag /= m_nFilterPoints; } output[i] = complex (sumReal, sumImag); }