From d58f6b51493c7931cbc02feb3ffeb0eca6ea3a4e Mon Sep 17 00:00:00 2001 From: Willem Jan Palenstijn Date: Thu, 5 Jul 2018 16:13:37 +0200 Subject: Refactor a few filter-related functions out of cuda code --- astra_vc14.vcxproj | 3 +- astra_vc14.vcxproj.filters | 9 +- build/linux/Makefile.in | 1 + build/msvc/gen.py | 3 +- cuda/2d/fbp.cu | 2 +- cuda/2d/fft.cu | 383 +--------------- cuda/3d/fdk.cu | 2 +- .../astra/CudaFilteredBackProjectionAlgorithm.h | 3 +- include/astra/Filters.h | 71 +++ include/astra/cuda/2d/astra.h | 1 - include/astra/cuda/2d/fbp.h | 2 +- include/astra/cuda/2d/fbp_filters.h | 61 --- include/astra/cuda/2d/fft.h | 8 +- src/CudaFilteredBackProjectionAlgorithm.cpp | 118 +---- src/Filters.cpp | 484 +++++++++++++++++++++ 15 files changed, 582 insertions(+), 569 deletions(-) create mode 100644 include/astra/Filters.h delete mode 100644 include/astra/cuda/2d/fbp_filters.h create mode 100644 src/Filters.cpp diff --git a/astra_vc14.vcxproj b/astra_vc14.vcxproj index 64c08ee..893305f 100644 --- a/astra_vc14.vcxproj +++ b/astra_vc14.vcxproj @@ -509,6 +509,7 @@ + @@ -596,6 +597,7 @@ + @@ -656,7 +658,6 @@ - diff --git a/astra_vc14.vcxproj.filters b/astra_vc14.vcxproj.filters index 3e9ff9a..fef6a8a 100644 --- a/astra_vc14.vcxproj.filters +++ b/astra_vc14.vcxproj.filters @@ -168,6 +168,9 @@ Global & Other\source + + Global & Other\source + Global & Other\source @@ -434,6 +437,9 @@ Global & Other\headers + + Global & Other\headers + Global & Other\headers @@ -638,9 +644,6 @@ CUDA\cuda headers - - CUDA\cuda headers - CUDA\cuda headers diff --git a/build/linux/Makefile.in b/build/linux/Makefile.in index 1627a2e..0b90bd9 100644 --- a/build/linux/Makefile.in +++ b/build/linux/Makefile.in @@ -142,6 +142,7 @@ BASE_OBJECTS=\ src/FanFlatProjectionGeometry2D.lo \ src/FanFlatVecProjectionGeometry2D.lo \ src/FilteredBackProjectionAlgorithm.lo \ + src/Filters.lo \ src/Float32Data2D.lo \ src/Float32Data3D.lo \ src/Float32Data3DMemory.lo \ diff --git a/build/msvc/gen.py b/build/msvc/gen.py index fcc12d2..47e7440 100644 --- a/build/msvc/gen.py +++ b/build/msvc/gen.py @@ -214,6 +214,7 @@ P_astra["filters"]["Global & Other\\source"] = [ "src\\AstraObjectManager.cpp", "src\\CompositeGeometryManager.cpp", "src\\Config.cpp", +"src\\Filters.cpp", "src\\Fourier.cpp", "src\\Globals.cpp", "src\\Logging.cpp", @@ -292,7 +293,6 @@ P_astra["filters"]["CUDA\\cuda headers"] = [ "include\\astra\\cuda\\2d\\em.h", "include\\astra\\cuda\\2d\\fan_bp.h", "include\\astra\\cuda\\2d\\fan_fp.h", -"include\\astra\\cuda\\2d\\fbp_filters.h", "include\\astra\\cuda\\2d\\fbp.h", "include\\astra\\cuda\\2d\\fft.h", "include\\astra\\cuda\\2d\\par_bp.h", @@ -354,6 +354,7 @@ P_astra["filters"]["Global & Other\\headers"] = [ "include\\astra\\clog.h", "include\\astra\\CompositeGeometryManager.h", "include\\astra\\Config.h", +"include\\astra\\Filters.h", "include\\astra\\Fourier.h", "include\\astra\\Globals.h", "include\\astra\\Logging.h", diff --git a/cuda/2d/fbp.cu b/cuda/2d/fbp.cu index 48fb7dc..7a8d2e9 100644 --- a/cuda/2d/fbp.cu +++ b/cuda/2d/fbp.cu @@ -130,7 +130,7 @@ bool FBP::setFilter(astra::E_FBPFILTER _eFilter, const float * _pfHostFilter /* case astra::FILTER_FLATTOP: case astra::FILTER_PARZEN: { - genFilter(_eFilter, _fD, dims.iProjAngles, pHostFilter, iFFTRealDetCount, iFreqBinCount, _fFilterParameter); + genCuFFTFilter(_eFilter, _fD, dims.iProjAngles, pHostFilter, iFFTRealDetCount, iFreqBinCount, _fFilterParameter); uploadComplexArrayToDevice(dims.iProjAngles, iFreqBinCount, pHostFilter, (cufftComplex*)D_filter); break; diff --git a/cuda/2d/fft.cu b/cuda/2d/fft.cu index bd8cab5..4454746 100644 --- a/cuda/2d/fft.cu +++ b/cuda/2d/fft.cu @@ -300,387 +300,13 @@ void genIdenFilter(int _iProjectionCount, cufftComplex * _pFilter, } } -void genFilter(E_FBPFILTER _eFilter, float _fD, int _iProjectionCount, +void genCuFFTFilter(E_FBPFILTER _eFilter, float _fD, int _iProjectionCount, cufftComplex * _pFilter, int _iFFTRealDetectorCount, int _iFFTFourierDetectorCount, float _fParameter /* = -1.0f */) { - float * pfFilt = new float[_iFFTFourierDetectorCount]; - float * pfW = new float[_iFFTFourierDetectorCount]; - - // We cache one Fourier transform for repeated FBP's of the same size - static float *pfData = 0; - static int iFilterCacheSize = 0; - - if (!pfData || iFilterCacheSize != _iFFTRealDetectorCount) { - // Compute filter in spatial domain - - delete[] pfData; - pfData = new float[2*_iFFTRealDetectorCount]; - int *ip = new int[int(2+sqrt(_iFFTRealDetectorCount)+1)]; - ip[0] = 0; - float32 *w = new float32[_iFFTRealDetectorCount/2]; - - for (int i = 0; i < _iFFTRealDetectorCount; ++i) { - pfData[2*i+1] = 0.0f; - - if (i & 1) { - int j = i; - if (2*j > _iFFTRealDetectorCount) - j = _iFFTRealDetectorCount - j; - float f = M_PI * j; - pfData[2*i] = -1 / (f*f); - } else { - pfData[2*i] = 0.0f; - } - } - - pfData[0] = 0.25f; - - cdft(2*_iFFTRealDetectorCount, -1, pfData, ip, w); - delete[] ip; - delete[] w; - - iFilterCacheSize = _iFFTRealDetectorCount; - } - - for(int iDetectorIndex = 0; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) - { - float fRelIndex = (float)iDetectorIndex / (float)_iFFTRealDetectorCount; - - pfFilt[iDetectorIndex] = 2.0f * pfData[2*iDetectorIndex]; - pfW[iDetectorIndex] = M_PI * 2.0f * fRelIndex; - } - - switch(_eFilter) - { - case FILTER_RAMLAK: - { - // do nothing - break; - } - case FILTER_SHEPPLOGAN: - { - // filt(2:end) = filt(2:end) .* (sin(w(2:end)/(2*d))./(w(2:end)/(2*d))) - for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) - { - pfFilt[iDetectorIndex] = pfFilt[iDetectorIndex] * (sinf(pfW[iDetectorIndex] / 2.0f / _fD) / (pfW[iDetectorIndex] / 2.0f / _fD)); - } - break; - } - case FILTER_COSINE: - { - // filt(2:end) = filt(2:end) .* cos(w(2:end)/(2*d)) - for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) - { - pfFilt[iDetectorIndex] = pfFilt[iDetectorIndex] * cosf(pfW[iDetectorIndex] / 2.0f / _fD); - } - break; - } - case FILTER_HAMMING: - { - // filt(2:end) = filt(2:end) .* (.54 + .46 * cos(w(2:end)/d)) - for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) - { - pfFilt[iDetectorIndex] = pfFilt[iDetectorIndex] * ( 0.54f + 0.46f * cosf(pfW[iDetectorIndex] / _fD)); - } - break; - } - case FILTER_HANN: - { - // filt(2:end) = filt(2:end) .*(1+cos(w(2:end)./d)) / 2 - for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) - { - pfFilt[iDetectorIndex] = pfFilt[iDetectorIndex] * (1.0f + cosf(pfW[iDetectorIndex] / _fD)) / 2.0f; - } - break; - } - case FILTER_TUKEY: - { - float fAlpha = _fParameter; - if(_fParameter < 0.0f) fAlpha = 0.5f; - float fN = (float)_iFFTFourierDetectorCount; - float fHalfN = fN / 2.0f; - float fEnumTerm = fAlpha * fHalfN; - float fDenom = (1.0f - fAlpha) * fHalfN; - float fBlockStart = fHalfN - fEnumTerm; - float fBlockEnd = fHalfN + fEnumTerm; - - for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) - { - float fAbsSmallN = fabs((float)iDetectorIndex); - float fStoredValue = 0.0f; - - if((fBlockStart <= fAbsSmallN) && (fAbsSmallN <= fBlockEnd)) - { - fStoredValue = 1.0f; - } - else - { - float fEnum = fAbsSmallN - fEnumTerm; - float fCosInput = M_PI * fEnum / fDenom; - fStoredValue = 0.5f * (1.0f + cosf(fCosInput)); - } - - pfFilt[iDetectorIndex] *= fStoredValue; - } - - break; - } - case FILTER_LANCZOS: - { - float fDenum = (float)(_iFFTFourierDetectorCount - 1); - - for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) - { - float fSmallN = (float)iDetectorIndex; - float fX = 2.0f * fSmallN / fDenum - 1.0f; - float fSinInput = M_PI * fX; - float fStoredValue = 0.0f; - - if(fabsf(fSinInput) > 0.001f) - { - fStoredValue = sin(fSinInput)/fSinInput; - } - else - { - fStoredValue = 1.0f; - } - - pfFilt[iDetectorIndex] *= fStoredValue; - } - - break; - } - case FILTER_TRIANGULAR: - { - float fNMinusOne = (float)(_iFFTFourierDetectorCount - 1); - - for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) - { - float fSmallN = (float)iDetectorIndex; - float fAbsInput = fSmallN - fNMinusOne / 2.0f; - float fParenInput = fNMinusOne / 2.0f - fabsf(fAbsInput); - float fStoredValue = 2.0f / fNMinusOne * fParenInput; - - pfFilt[iDetectorIndex] *= fStoredValue; - } - - break; - } - case FILTER_GAUSSIAN: - { - float fSigma = _fParameter; - if(_fParameter < 0.0f) fSigma = 0.4f; - float fN = (float)_iFFTFourierDetectorCount; - float fQuotient = (fN - 1.0f) / 2.0f; - - for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) - { - float fSmallN = (float)iDetectorIndex; - float fEnum = fSmallN - fQuotient; - float fDenom = fSigma * fQuotient; - float fPower = -0.5f * (fEnum / fDenom) * (fEnum / fDenom); - float fStoredValue = expf(fPower); - - pfFilt[iDetectorIndex] *= fStoredValue; - } - - break; - } - case FILTER_BARTLETTHANN: - { - const float fA0 = 0.62f; - const float fA1 = 0.48f; - const float fA2 = 0.38f; - float fNMinusOne = (float)(_iFFTFourierDetectorCount) - 1.0f; - - for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) - { - float fSmallN = (float)iDetectorIndex; - float fAbsInput = fSmallN / fNMinusOne - 0.5f; - float fFirstTerm = fA1 * fabsf(fAbsInput); - float fCosInput = 2.0f * M_PI * fSmallN / fNMinusOne; - float fSecondTerm = fA2 * cosf(fCosInput); - float fStoredValue = fA0 - fFirstTerm - fSecondTerm; - - pfFilt[iDetectorIndex] *= fStoredValue; - } - - break; - } - case FILTER_BLACKMAN: - { - float fAlpha = _fParameter; - if(_fParameter < 0.0f) fAlpha = 0.16f; - float fA0 = (1.0f - fAlpha) / 2.0f; - float fA1 = 0.5f; - float fA2 = fAlpha / 2.0f; - float fNMinusOne = (float)(_iFFTFourierDetectorCount - 1); - - for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) - { - float fSmallN = (float)iDetectorIndex; - float fCosInput1 = 2.0f * M_PI * 0.5f * fSmallN / fNMinusOne; - float fCosInput2 = 4.0f * M_PI * 0.5f * fSmallN / fNMinusOne; - float fStoredValue = fA0 - fA1 * cosf(fCosInput1) + fA2 * cosf(fCosInput2); - - pfFilt[iDetectorIndex] *= fStoredValue; - } - - break; - } - case FILTER_NUTTALL: - { - const float fA0 = 0.355768f; - const float fA1 = 0.487396f; - const float fA2 = 0.144232f; - const float fA3 = 0.012604f; - float fNMinusOne = (float)(_iFFTFourierDetectorCount) - 1.0f; - - for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) - { - float fSmallN = (float)iDetectorIndex; - float fBaseCosInput = M_PI * fSmallN / fNMinusOne; - float fFirstTerm = fA1 * cosf(2.0f * fBaseCosInput); - float fSecondTerm = fA2 * cosf(4.0f * fBaseCosInput); - float fThirdTerm = fA3 * cosf(6.0f * fBaseCosInput); - float fStoredValue = fA0 - fFirstTerm + fSecondTerm - fThirdTerm; - - pfFilt[iDetectorIndex] *= fStoredValue; - } - - break; - } - case FILTER_BLACKMANHARRIS: - { - const float fA0 = 0.35875f; - const float fA1 = 0.48829f; - const float fA2 = 0.14128f; - const float fA3 = 0.01168f; - float fNMinusOne = (float)(_iFFTFourierDetectorCount) - 1.0f; - - for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) - { - float fSmallN = (float)iDetectorIndex; - float fBaseCosInput = M_PI * fSmallN / fNMinusOne; - float fFirstTerm = fA1 * cosf(2.0f * fBaseCosInput); - float fSecondTerm = fA2 * cosf(4.0f * fBaseCosInput); - float fThirdTerm = fA3 * cosf(6.0f * fBaseCosInput); - float fStoredValue = fA0 - fFirstTerm + fSecondTerm - fThirdTerm; - - pfFilt[iDetectorIndex] *= fStoredValue; - } - - break; - } - case FILTER_BLACKMANNUTTALL: - { - const float fA0 = 0.3635819f; - const float fA1 = 0.4891775f; - const float fA2 = 0.1365995f; - const float fA3 = 0.0106411f; - float fNMinusOne = (float)(_iFFTFourierDetectorCount) - 1.0f; - - for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) - { - float fSmallN = (float)iDetectorIndex; - float fBaseCosInput = M_PI * fSmallN / fNMinusOne; - float fFirstTerm = fA1 * cosf(2.0f * fBaseCosInput); - float fSecondTerm = fA2 * cosf(4.0f * fBaseCosInput); - float fThirdTerm = fA3 * cosf(6.0f * fBaseCosInput); - float fStoredValue = fA0 - fFirstTerm + fSecondTerm - fThirdTerm; - - pfFilt[iDetectorIndex] *= fStoredValue; - } - - break; - } - case FILTER_FLATTOP: - { - const float fA0 = 1.0f; - const float fA1 = 1.93f; - const float fA2 = 1.29f; - const float fA3 = 0.388f; - const float fA4 = 0.032f; - float fNMinusOne = (float)(_iFFTFourierDetectorCount) - 1.0f; - - for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) - { - float fSmallN = (float)iDetectorIndex; - float fBaseCosInput = M_PI * fSmallN / fNMinusOne; - float fFirstTerm = fA1 * cosf(2.0f * fBaseCosInput); - float fSecondTerm = fA2 * cosf(4.0f * fBaseCosInput); - float fThirdTerm = fA3 * cosf(6.0f * fBaseCosInput); - float fFourthTerm = fA4 * cosf(8.0f * fBaseCosInput); - float fStoredValue = fA0 - fFirstTerm + fSecondTerm - fThirdTerm + fFourthTerm; - - pfFilt[iDetectorIndex] *= fStoredValue; - } - - break; - } - case FILTER_KAISER: - { - float fAlpha = _fParameter; - if(_fParameter < 0.0f) fAlpha = 3.0f; - float fPiTimesAlpha = M_PI * fAlpha; - float fNMinusOne = (float)(_iFFTFourierDetectorCount - 1); - float fDenom = (float)j0((double)fPiTimesAlpha); - - for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) - { - float fSmallN = (float)iDetectorIndex; - float fSquareInput = 2.0f * fSmallN / fNMinusOne - 1; - float fSqrtInput = 1.0f - fSquareInput * fSquareInput; - float fBesselInput = fPiTimesAlpha * sqrt(fSqrtInput); - float fEnum = (float)j0((double)fBesselInput); - float fStoredValue = fEnum / fDenom; - - pfFilt[iDetectorIndex] *= fStoredValue; - } - - break; - } - case FILTER_PARZEN: - { - for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) - { - float fSmallN = (float)iDetectorIndex; - float fQ = fSmallN / (float)(_iFFTFourierDetectorCount - 1); - float fStoredValue = 0.0f; - - if(fQ <= 0.5f) - { - fStoredValue = 1.0f - 6.0f * fQ * fQ * (1.0f - fQ); - } - else - { - float fCubedValue = 1.0f - fQ; - fStoredValue = 2.0f * fCubedValue * fCubedValue * fCubedValue; - } - - pfFilt[iDetectorIndex] *= fStoredValue; - } - - break; - } - default: - { - ASTRA_ERROR("Cannot serve requested filter"); - } - } - - // filt(w>pi*d) = 0; - float fPiTimesD = M_PI * _fD; - for(int iDetectorIndex = 0; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) - { - float fWValue = pfW[iDetectorIndex]; - - if(fWValue > fPiTimesD) - { - pfFilt[iDetectorIndex] = 0.0f; - } - } + float * pfFilt = astra::genFilter(_eFilter, _fD, _iProjectionCount, + _iFFTRealDetectorCount, + _iFFTFourierDetectorCount, _fParameter); for(int iDetectorIndex = 0; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) { @@ -695,7 +321,6 @@ void genFilter(E_FBPFILTER _eFilter, float _fD, int _iProjectionCount, } delete[] pfFilt; - delete[] pfW; } diff --git a/cuda/3d/fdk.cu b/cuda/3d/fdk.cu index 46c07e7..194d2fb 100644 --- a/cuda/3d/fdk.cu +++ b/cuda/3d/fdk.cu @@ -253,7 +253,7 @@ bool FDK_Filter(cudaPitchedPtr D_projData, memset(pHostFilter, 0, sizeof(cufftComplex) * dims.iProjAngles * iHalfFFTSize); if (pfFilter == 0){ - astraCUDA::genFilter(astra::FILTER_RAMLAK, 1.0f, dims.iProjAngles, pHostFilter, iPaddedDetCount, iHalfFFTSize); + astraCUDA::genCuFFTFilter(astra::FILTER_RAMLAK, 1.0f, dims.iProjAngles, pHostFilter, iPaddedDetCount, iHalfFFTSize); } else { for (int i = 0; i < dims.iProjAngles * iHalfFFTSize; i++) { pHostFilter[i].x = pfFilter[i]; diff --git a/include/astra/CudaFilteredBackProjectionAlgorithm.h b/include/astra/CudaFilteredBackProjectionAlgorithm.h index 1280e9a..974914a 100644 --- a/include/astra/CudaFilteredBackProjectionAlgorithm.h +++ b/include/astra/CudaFilteredBackProjectionAlgorithm.h @@ -33,6 +33,7 @@ along with the ASTRA Toolbox. If not, see . #include "Float32ProjectionData2D.h" #include "Float32VolumeData2D.h" #include "CudaReconstructionAlgorithm2D.h" +#include "Filters.h" #include "cuda/2d/astra.h" @@ -52,8 +53,6 @@ private: float m_fFilterD; // frequency cut-off bool m_bShortScan; // short-scan mode for fan beam - static E_FBPFILTER _convertStringToFilter(const char * _filterType); - public: CCudaFilteredBackProjectionAlgorithm(); virtual ~CCudaFilteredBackProjectionAlgorithm(); diff --git a/include/astra/Filters.h b/include/astra/Filters.h new file mode 100644 index 0000000..ff3f5c8 --- /dev/null +++ b/include/astra/Filters.h @@ -0,0 +1,71 @@ +/* +----------------------------------------------------------------------- +Copyright: 2010-2018, imec Vision Lab, University of Antwerp + 2014-2018, CWI, Amsterdam + +Contact: astra@astra-toolbox.com +Website: http://www.astra-toolbox.com/ + +This file is part of the ASTRA Toolbox. + + +The ASTRA Toolbox is free software: you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation, either version 3 of the License, or +(at your option) any later version. + +The ASTRA Toolbox is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with the ASTRA Toolbox. If not, see . + +----------------------------------------------------------------------- +*/ + +#ifndef _INC_ASTRA_FILTERS_H +#define _INC_ASTRA_FILTERS_H + +namespace astra { + +enum E_FBPFILTER +{ + FILTER_ERROR, //< not a valid filter + FILTER_NONE, //< no filter (regular BP) + FILTER_RAMLAK, //< default FBP filter + FILTER_SHEPPLOGAN, //< Shepp-Logan + FILTER_COSINE, //< Cosine + FILTER_HAMMING, //< Hamming filter + FILTER_HANN, //< Hann filter + FILTER_TUKEY, //< Tukey filter + FILTER_LANCZOS, //< Lanczos filter + FILTER_TRIANGULAR, //< Triangular filter + FILTER_GAUSSIAN, //< Gaussian filter + FILTER_BARTLETTHANN, //< Bartlett-Hann filter + FILTER_BLACKMAN, //< Blackman filter + FILTER_NUTTALL, //< Nuttall filter, continuous first derivative + FILTER_BLACKMANHARRIS, //< Blackman-Harris filter + FILTER_BLACKMANNUTTALL, //< Blackman-Nuttall filter + FILTER_FLATTOP, //< Flat top filter + FILTER_KAISER, //< Kaiser filter + FILTER_PARZEN, //< Parzen filter + FILTER_PROJECTION, //< all projection directions share one filter + FILTER_SINOGRAM, //< every projection direction has its own filter + FILTER_RPROJECTION, //< projection filter in real space (as opposed to fourier space) + FILTER_RSINOGRAM, //< sinogram filter in real space + +}; + +// Generate filter of given size and parameters. Returns newly allocated array. +float *genFilter(E_FBPFILTER _eFilter, float _fD, int _iProjectionCount, + int _iFFTRealDetectorCount, + int _iFFTFourierDetectorCount, float _fParameter = -1.0f); + +// Convert string to filter type. Returns FILTER_ERROR if unrecognized. +E_FBPFILTER convertStringToFilter(const char * _filterType); + +} + +#endif diff --git a/include/astra/cuda/2d/astra.h b/include/astra/cuda/2d/astra.h index 6f0e2f0..a2f2219 100644 --- a/include/astra/cuda/2d/astra.h +++ b/include/astra/cuda/2d/astra.h @@ -28,7 +28,6 @@ along with the ASTRA Toolbox. If not, see . #ifndef _CUDA_ASTRA_H #define _CUDA_ASTRA_H -#include "fbp_filters.h" #include "dims.h" #include "algo.h" diff --git a/include/astra/cuda/2d/fbp.h b/include/astra/cuda/2d/fbp.h index 8666646..7febe69 100644 --- a/include/astra/cuda/2d/fbp.h +++ b/include/astra/cuda/2d/fbp.h @@ -26,7 +26,7 @@ along with the ASTRA Toolbox. If not, see . */ #include "algo.h" -#include "fbp_filters.h" +#include "astra/Filters.h" namespace astraCUDA { diff --git a/include/astra/cuda/2d/fbp_filters.h b/include/astra/cuda/2d/fbp_filters.h deleted file mode 100644 index 7c1121a..0000000 --- a/include/astra/cuda/2d/fbp_filters.h +++ /dev/null @@ -1,61 +0,0 @@ -/* ------------------------------------------------------------------------ -Copyright: 2010-2018, imec Vision Lab, University of Antwerp - 2014-2018, CWI, Amsterdam - -Contact: astra@astra-toolbox.com -Website: http://www.astra-toolbox.com/ - -This file is part of the ASTRA Toolbox. - - -The ASTRA Toolbox is free software: you can redistribute it and/or modify -it under the terms of the GNU General Public License as published by -the Free Software Foundation, either version 3 of the License, or -(at your option) any later version. - -The ASTRA Toolbox is distributed in the hope that it will be useful, -but WITHOUT ANY WARRANTY; without even the implied warranty of -MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -GNU General Public License for more details. - -You should have received a copy of the GNU General Public License -along with the ASTRA Toolbox. If not, see . - ------------------------------------------------------------------------ -*/ - -#ifndef FBP_FILTERS_H -#define FBP_FILTERS_H - -namespace astra { - -enum E_FBPFILTER -{ - FILTER_NONE, //< no filter (regular BP) - FILTER_RAMLAK, //< default FBP filter - FILTER_SHEPPLOGAN, //< Shepp-Logan - FILTER_COSINE, //< Cosine - FILTER_HAMMING, //< Hamming filter - FILTER_HANN, //< Hann filter - FILTER_TUKEY, //< Tukey filter - FILTER_LANCZOS, //< Lanczos filter - FILTER_TRIANGULAR, //< Triangular filter - FILTER_GAUSSIAN, //< Gaussian filter - FILTER_BARTLETTHANN, //< Bartlett-Hann filter - FILTER_BLACKMAN, //< Blackman filter - FILTER_NUTTALL, //< Nuttall filter, continuous first derivative - FILTER_BLACKMANHARRIS, //< Blackman-Harris filter - FILTER_BLACKMANNUTTALL, //< Blackman-Nuttall filter - FILTER_FLATTOP, //< Flat top filter - FILTER_KAISER, //< Kaiser filter - FILTER_PARZEN, //< Parzen filter - FILTER_PROJECTION, //< all projection directions share one filter - FILTER_SINOGRAM, //< every projection direction has its own filter - FILTER_RPROJECTION, //< projection filter in real space (as opposed to fourier space) - FILTER_RSINOGRAM, //< sinogram filter in real space -}; - -} - -#endif /* FBP_FILTERS_H */ diff --git a/include/astra/cuda/2d/fft.h b/include/astra/cuda/2d/fft.h index d36cae2..f5f8477 100644 --- a/include/astra/cuda/2d/fft.h +++ b/include/astra/cuda/2d/fft.h @@ -31,7 +31,7 @@ along with the ASTRA Toolbox. If not, see . #include #include -#include "fbp_filters.h" +#include "astra/Filters.h" namespace astraCUDA { @@ -60,9 +60,9 @@ void applyFilter(int _iProjectionCount, int _iFreqBinCount, int calcFFTFourierSize(int _iFFTRealSize); -void genFilter(astra::E_FBPFILTER _eFilter, float _fD, int _iProjectionCount, - cufftComplex * _pFilter, int _iFFTRealDetectorCount, - int _iFFTFourierDetectorCount, float _fParameter = -1.0f); +void genCuFFTFilter(astra::E_FBPFILTER _eFilter, float _fD, int _iProjectionCount, + cufftComplex * _pFilter, int _iFFTRealDetectorCount, + int _iFFTFourierDetectorCount, float _fParameter = -1.0f); void genIdenFilter(int _iProjectionCount, cufftComplex * _pFilter, int _iFFTRealDetectorCount, int _iFFTFourierDetectorCount); diff --git a/src/CudaFilteredBackProjectionAlgorithm.cpp b/src/CudaFilteredBackProjectionAlgorithm.cpp index 944f165..9ebbd60 100644 --- a/src/CudaFilteredBackProjectionAlgorithm.cpp +++ b/src/CudaFilteredBackProjectionAlgorithm.cpp @@ -27,10 +27,10 @@ along with the ASTRA Toolbox. If not, see . #include #include -#include #include "astra/AstraObjectManager.h" #include "astra/CudaProjector2D.h" +#include "astra/Filters.h" #include "astra/cuda/2d/astra.h" #include "astra/cuda/2d/fbp.h" @@ -75,7 +75,7 @@ bool CCudaFilteredBackProjectionAlgorithm::initialize(const Config& _cfg) // filter type XMLNode node = _cfg.self.getSingleNode("FilterType"); if (node) - m_eFilter = _convertStringToFilter(node.getContent().c_str()); + m_eFilter = convertStringToFilter(node.getContent().c_str()); else m_eFilter = FILTER_RAMLAK; CC.markNodeParsed("FilterType"); @@ -215,6 +215,8 @@ bool CCudaFilteredBackProjectionAlgorithm::check() ASTRA_CONFIG_CHECK(m_pSinogram, "FBP_CUDA", "Invalid Projection Data Object."); ASTRA_CONFIG_CHECK(m_pReconstruction, "FBP_CUDA", "Invalid Reconstruction Data Object."); + ASTRA_CONFIG_CHECK(m_eFilter != FILTER_ERROR, "FBP_CUDA", "Invalid filter name."); + if((m_eFilter == FILTER_PROJECTION) || (m_eFilter == FILTER_SINOGRAM) || (m_eFilter == FILTER_RPROJECTION) || (m_eFilter == FILTER_RSINOGRAM)) { ASTRA_CONFIG_CHECK(m_pfFilter, "FBP_CUDA", "Invalid filter pointer."); @@ -235,116 +237,4 @@ bool CCudaFilteredBackProjectionAlgorithm::check() return true; } -static bool stringCompareLowerCase(const char * _stringA, const char * _stringB) -{ - int iCmpReturn = 0; - -#ifdef _MSC_VER - iCmpReturn = _stricmp(_stringA, _stringB); -#else - iCmpReturn = strcasecmp(_stringA, _stringB); -#endif - - return (iCmpReturn == 0); -} - -E_FBPFILTER CCudaFilteredBackProjectionAlgorithm::_convertStringToFilter(const char * _filterType) -{ - E_FBPFILTER output = FILTER_NONE; - - if(stringCompareLowerCase(_filterType, "ram-lak")) - { - output = FILTER_RAMLAK; - } - else if(stringCompareLowerCase(_filterType, "shepp-logan")) - { - output = FILTER_SHEPPLOGAN; - } - else if(stringCompareLowerCase(_filterType, "cosine")) - { - output = FILTER_COSINE; - } - else if(stringCompareLowerCase(_filterType, "hamming")) - { - output = FILTER_HAMMING; - } - else if(stringCompareLowerCase(_filterType, "hann")) - { - output = FILTER_HANN; - } - else if(stringCompareLowerCase(_filterType, "none")) - { - output = FILTER_NONE; - } - else if(stringCompareLowerCase(_filterType, "tukey")) - { - output = FILTER_TUKEY; - } - else if(stringCompareLowerCase(_filterType, "lanczos")) - { - output = FILTER_LANCZOS; - } - else if(stringCompareLowerCase(_filterType, "triangular")) - { - output = FILTER_TRIANGULAR; - } - else if(stringCompareLowerCase(_filterType, "gaussian")) - { - output = FILTER_GAUSSIAN; - } - else if(stringCompareLowerCase(_filterType, "barlett-hann")) - { - output = FILTER_BARTLETTHANN; - } - else if(stringCompareLowerCase(_filterType, "blackman")) - { - output = FILTER_BLACKMAN; - } - else if(stringCompareLowerCase(_filterType, "nuttall")) - { - output = FILTER_NUTTALL; - } - else if(stringCompareLowerCase(_filterType, "blackman-harris")) - { - output = FILTER_BLACKMANHARRIS; - } - else if(stringCompareLowerCase(_filterType, "blackman-nuttall")) - { - output = FILTER_BLACKMANNUTTALL; - } - else if(stringCompareLowerCase(_filterType, "flat-top")) - { - output = FILTER_FLATTOP; - } - else if(stringCompareLowerCase(_filterType, "kaiser")) - { - output = FILTER_KAISER; - } - else if(stringCompareLowerCase(_filterType, "parzen")) - { - output = FILTER_PARZEN; - } - else if(stringCompareLowerCase(_filterType, "projection")) - { - output = FILTER_PROJECTION; - } - else if(stringCompareLowerCase(_filterType, "sinogram")) - { - output = FILTER_SINOGRAM; - } - else if(stringCompareLowerCase(_filterType, "rprojection")) - { - output = FILTER_RPROJECTION; - } - else if(stringCompareLowerCase(_filterType, "rsinogram")) - { - output = FILTER_RSINOGRAM; - } - else - { - ASTRA_ERROR("Failed to convert \"%s\" into a filter.",_filterType); - } - - return output; -} diff --git a/src/Filters.cpp b/src/Filters.cpp new file mode 100644 index 0000000..30b2f24 --- /dev/null +++ b/src/Filters.cpp @@ -0,0 +1,484 @@ +/* +----------------------------------------------------------------------- +Copyright: 2010-2018, imec Vision Lab, University of Antwerp + 2014-2018, CWI, Amsterdam + +Contact: astra@astra-toolbox.com +Website: http://www.astra-toolbox.com/ + +This file is part of the ASTRA Toolbox. + + +The ASTRA Toolbox is free software: you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation, either version 3 of the License, or +(at your option) any later version. + +The ASTRA Toolbox is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with the ASTRA Toolbox. If not, see . + +----------------------------------------------------------------------- +*/ + +#include "astra/Globals.h" +#include "astra/Logging.h" +#include "astra/Fourier.h" +#include "astra/Filters.h" + +#include +#include + +namespace astra { + +float *genFilter(E_FBPFILTER _eFilter, float _fD, int _iProjectionCount, + int _iFFTRealDetectorCount, + int _iFFTFourierDetectorCount, float _fParameter /* = -1.0f */) +{ + float * pfFilt = new float[_iFFTFourierDetectorCount]; + float * pfW = new float[_iFFTFourierDetectorCount]; + + // We cache one Fourier transform for repeated FBP's of the same size + static float *pfData = 0; + static int iFilterCacheSize = 0; + + if (!pfData || iFilterCacheSize != _iFFTRealDetectorCount) { + // Compute filter in spatial domain + + delete[] pfData; + pfData = new float[2*_iFFTRealDetectorCount]; + int *ip = new int[int(2+sqrt(_iFFTRealDetectorCount)+1)]; + ip[0] = 0; + float32 *w = new float32[_iFFTRealDetectorCount/2]; + + for (int i = 0; i < _iFFTRealDetectorCount; ++i) { + pfData[2*i+1] = 0.0f; + + if (i & 1) { + int j = i; + if (2*j > _iFFTRealDetectorCount) + j = _iFFTRealDetectorCount - j; + float f = M_PI * j; + pfData[2*i] = -1 / (f*f); + } else { + pfData[2*i] = 0.0f; + } + } + + pfData[0] = 0.25f; + + cdft(2*_iFFTRealDetectorCount, -1, pfData, ip, w); + delete[] ip; + delete[] w; + + iFilterCacheSize = _iFFTRealDetectorCount; + } + + for(int iDetectorIndex = 0; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) + { + float fRelIndex = (float)iDetectorIndex / (float)_iFFTRealDetectorCount; + + pfFilt[iDetectorIndex] = 2.0f * pfData[2*iDetectorIndex]; + pfW[iDetectorIndex] = M_PI * 2.0f * fRelIndex; + } + + switch(_eFilter) + { + case FILTER_RAMLAK: + { + // do nothing + break; + } + case FILTER_SHEPPLOGAN: + { + // filt(2:end) = filt(2:end) .* (sin(w(2:end)/(2*d))./(w(2:end)/(2*d))) + for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) + { + pfFilt[iDetectorIndex] = pfFilt[iDetectorIndex] * (sinf(pfW[iDetectorIndex] / 2.0f / _fD) / (pfW[iDetectorIndex] / 2.0f / _fD)); + } + break; + } + case FILTER_COSINE: + { + // filt(2:end) = filt(2:end) .* cos(w(2:end)/(2*d)) + for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) + { + pfFilt[iDetectorIndex] = pfFilt[iDetectorIndex] * cosf(pfW[iDetectorIndex] / 2.0f / _fD); + } + break; + } + case FILTER_HAMMING: + { + // filt(2:end) = filt(2:end) .* (.54 + .46 * cos(w(2:end)/d)) + for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) + { + pfFilt[iDetectorIndex] = pfFilt[iDetectorIndex] * ( 0.54f + 0.46f * cosf(pfW[iDetectorIndex] / _fD)); + } + break; + } + case FILTER_HANN: + { + // filt(2:end) = filt(2:end) .*(1+cos(w(2:end)./d)) / 2 + for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) + { + pfFilt[iDetectorIndex] = pfFilt[iDetectorIndex] * (1.0f + cosf(pfW[iDetectorIndex] / _fD)) / 2.0f; + } + break; + } + case FILTER_TUKEY: + { + float fAlpha = _fParameter; + if(_fParameter < 0.0f) fAlpha = 0.5f; + float fN = (float)_iFFTFourierDetectorCount; + float fHalfN = fN / 2.0f; + float fEnumTerm = fAlpha * fHalfN; + float fDenom = (1.0f - fAlpha) * fHalfN; + float fBlockStart = fHalfN - fEnumTerm; + float fBlockEnd = fHalfN + fEnumTerm; + + for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) + { + float fAbsSmallN = fabs((float)iDetectorIndex); + float fStoredValue = 0.0f; + + if((fBlockStart <= fAbsSmallN) && (fAbsSmallN <= fBlockEnd)) + { + fStoredValue = 1.0f; + } + else + { + float fEnum = fAbsSmallN - fEnumTerm; + float fCosInput = M_PI * fEnum / fDenom; + fStoredValue = 0.5f * (1.0f + cosf(fCosInput)); + } + + pfFilt[iDetectorIndex] *= fStoredValue; + } + + break; + } + case FILTER_LANCZOS: + { + float fDenum = (float)(_iFFTFourierDetectorCount - 1); + + for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) + { + float fSmallN = (float)iDetectorIndex; + float fX = 2.0f * fSmallN / fDenum - 1.0f; + float fSinInput = M_PI * fX; + float fStoredValue = 0.0f; + + if(fabsf(fSinInput) > 0.001f) + { + fStoredValue = sin(fSinInput)/fSinInput; + } + else + { + fStoredValue = 1.0f; + } + + pfFilt[iDetectorIndex] *= fStoredValue; + } + + break; + } + case FILTER_TRIANGULAR: + { + float fNMinusOne = (float)(_iFFTFourierDetectorCount - 1); + + for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) + { + float fSmallN = (float)iDetectorIndex; + float fAbsInput = fSmallN - fNMinusOne / 2.0f; + float fParenInput = fNMinusOne / 2.0f - fabsf(fAbsInput); + float fStoredValue = 2.0f / fNMinusOne * fParenInput; + + pfFilt[iDetectorIndex] *= fStoredValue; + } + + break; + } + case FILTER_GAUSSIAN: + { + float fSigma = _fParameter; + if(_fParameter < 0.0f) fSigma = 0.4f; + float fN = (float)_iFFTFourierDetectorCount; + float fQuotient = (fN - 1.0f) / 2.0f; + + for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) + { + float fSmallN = (float)iDetectorIndex; + float fEnum = fSmallN - fQuotient; + float fDenom = fSigma * fQuotient; + float fPower = -0.5f * (fEnum / fDenom) * (fEnum / fDenom); + float fStoredValue = expf(fPower); + + pfFilt[iDetectorIndex] *= fStoredValue; + } + + break; + } + case FILTER_BARTLETTHANN: + { + const float fA0 = 0.62f; + const float fA1 = 0.48f; + const float fA2 = 0.38f; + float fNMinusOne = (float)(_iFFTFourierDetectorCount) - 1.0f; + + for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) + { + float fSmallN = (float)iDetectorIndex; + float fAbsInput = fSmallN / fNMinusOne - 0.5f; + float fFirstTerm = fA1 * fabsf(fAbsInput); + float fCosInput = 2.0f * M_PI * fSmallN / fNMinusOne; + float fSecondTerm = fA2 * cosf(fCosInput); + float fStoredValue = fA0 - fFirstTerm - fSecondTerm; + + pfFilt[iDetectorIndex] *= fStoredValue; + } + + break; + } + case FILTER_BLACKMAN: + { + float fAlpha = _fParameter; + if(_fParameter < 0.0f) fAlpha = 0.16f; + float fA0 = (1.0f - fAlpha) / 2.0f; + float fA1 = 0.5f; + float fA2 = fAlpha / 2.0f; + float fNMinusOne = (float)(_iFFTFourierDetectorCount - 1); + + for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) + { + float fSmallN = (float)iDetectorIndex; + float fCosInput1 = 2.0f * M_PI * 0.5f * fSmallN / fNMinusOne; + float fCosInput2 = 4.0f * M_PI * 0.5f * fSmallN / fNMinusOne; + float fStoredValue = fA0 - fA1 * cosf(fCosInput1) + fA2 * cosf(fCosInput2); + + pfFilt[iDetectorIndex] *= fStoredValue; + } + + break; + } + case FILTER_NUTTALL: + { + const float fA0 = 0.355768f; + const float fA1 = 0.487396f; + const float fA2 = 0.144232f; + const float fA3 = 0.012604f; + float fNMinusOne = (float)(_iFFTFourierDetectorCount) - 1.0f; + + for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) + { + float fSmallN = (float)iDetectorIndex; + float fBaseCosInput = M_PI * fSmallN / fNMinusOne; + float fFirstTerm = fA1 * cosf(2.0f * fBaseCosInput); + float fSecondTerm = fA2 * cosf(4.0f * fBaseCosInput); + float fThirdTerm = fA3 * cosf(6.0f * fBaseCosInput); + float fStoredValue = fA0 - fFirstTerm + fSecondTerm - fThirdTerm; + + pfFilt[iDetectorIndex] *= fStoredValue; + } + + break; + } + case FILTER_BLACKMANHARRIS: + { + const float fA0 = 0.35875f; + const float fA1 = 0.48829f; + const float fA2 = 0.14128f; + const float fA3 = 0.01168f; + float fNMinusOne = (float)(_iFFTFourierDetectorCount) - 1.0f; + + for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) + { + float fSmallN = (float)iDetectorIndex; + float fBaseCosInput = M_PI * fSmallN / fNMinusOne; + float fFirstTerm = fA1 * cosf(2.0f * fBaseCosInput); + float fSecondTerm = fA2 * cosf(4.0f * fBaseCosInput); + float fThirdTerm = fA3 * cosf(6.0f * fBaseCosInput); + float fStoredValue = fA0 - fFirstTerm + fSecondTerm - fThirdTerm; + + pfFilt[iDetectorIndex] *= fStoredValue; + } + + break; + } + case FILTER_BLACKMANNUTTALL: + { + const float fA0 = 0.3635819f; + const float fA1 = 0.4891775f; + const float fA2 = 0.1365995f; + const float fA3 = 0.0106411f; + float fNMinusOne = (float)(_iFFTFourierDetectorCount) - 1.0f; + + for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) + { + float fSmallN = (float)iDetectorIndex; + float fBaseCosInput = M_PI * fSmallN / fNMinusOne; + float fFirstTerm = fA1 * cosf(2.0f * fBaseCosInput); + float fSecondTerm = fA2 * cosf(4.0f * fBaseCosInput); + float fThirdTerm = fA3 * cosf(6.0f * fBaseCosInput); + float fStoredValue = fA0 - fFirstTerm + fSecondTerm - fThirdTerm; + + pfFilt[iDetectorIndex] *= fStoredValue; + } + + break; + } + case FILTER_FLATTOP: + { + const float fA0 = 1.0f; + const float fA1 = 1.93f; + const float fA2 = 1.29f; + const float fA3 = 0.388f; + const float fA4 = 0.032f; + float fNMinusOne = (float)(_iFFTFourierDetectorCount) - 1.0f; + + for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) + { + float fSmallN = (float)iDetectorIndex; + float fBaseCosInput = M_PI * fSmallN / fNMinusOne; + float fFirstTerm = fA1 * cosf(2.0f * fBaseCosInput); + float fSecondTerm = fA2 * cosf(4.0f * fBaseCosInput); + float fThirdTerm = fA3 * cosf(6.0f * fBaseCosInput); + float fFourthTerm = fA4 * cosf(8.0f * fBaseCosInput); + float fStoredValue = fA0 - fFirstTerm + fSecondTerm - fThirdTerm + fFourthTerm; + + pfFilt[iDetectorIndex] *= fStoredValue; + } + + break; + } + case FILTER_KAISER: + { + float fAlpha = _fParameter; + if(_fParameter < 0.0f) fAlpha = 3.0f; + float fPiTimesAlpha = M_PI * fAlpha; + float fNMinusOne = (float)(_iFFTFourierDetectorCount - 1); + float fDenom = (float)j0((double)fPiTimesAlpha); + + for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) + { + float fSmallN = (float)iDetectorIndex; + float fSquareInput = 2.0f * fSmallN / fNMinusOne - 1; + float fSqrtInput = 1.0f - fSquareInput * fSquareInput; + float fBesselInput = fPiTimesAlpha * sqrt(fSqrtInput); + float fEnum = (float)j0((double)fBesselInput); + float fStoredValue = fEnum / fDenom; + + pfFilt[iDetectorIndex] *= fStoredValue; + } + + break; + } + case FILTER_PARZEN: + { + for(int iDetectorIndex = 1; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) + { + float fSmallN = (float)iDetectorIndex; + float fQ = fSmallN / (float)(_iFFTFourierDetectorCount - 1); + float fStoredValue = 0.0f; + + if(fQ <= 0.5f) + { + fStoredValue = 1.0f - 6.0f * fQ * fQ * (1.0f - fQ); + } + else + { + float fCubedValue = 1.0f - fQ; + fStoredValue = 2.0f * fCubedValue * fCubedValue * fCubedValue; + } + + pfFilt[iDetectorIndex] *= fStoredValue; + } + + break; + } + default: + { + ASTRA_ERROR("Cannot serve requested filter"); + } + } + + // filt(w>pi*d) = 0; + float fPiTimesD = M_PI * _fD; + for(int iDetectorIndex = 0; iDetectorIndex < _iFFTFourierDetectorCount; iDetectorIndex++) + { + float fWValue = pfW[iDetectorIndex]; + + if(fWValue > fPiTimesD) + { + pfFilt[iDetectorIndex] = 0.0f; + } + } + + delete[] pfW; + + return pfFilt; +} + +static bool stringCompareLowerCase(const char * _stringA, const char * _stringB) +{ + int iCmpReturn = 0; + +#ifdef _MSC_VER + iCmpReturn = _stricmp(_stringA, _stringB); +#else + iCmpReturn = strcasecmp(_stringA, _stringB); +#endif + + return (iCmpReturn == 0); +} + +struct FilterNameMapEntry { + const char *m_name; + E_FBPFILTER m_type; +}; + +E_FBPFILTER convertStringToFilter(const char * _filterType) +{ + + static const FilterNameMapEntry map[] = { + { "ram-lak", FILTER_RAMLAK }, + { "shepp-logan", FILTER_SHEPPLOGAN }, + { "cosine", FILTER_COSINE }, + { "hamming", FILTER_HAMMING}, + { "hann", FILTER_HANN}, + { "tukey", FILTER_TUKEY }, + { "lanczos", FILTER_LANCZOS}, + { "triangular", FILTER_TRIANGULAR}, + { "gaussian", FILTER_GAUSSIAN}, + { "barlett-hann", FILTER_BARTLETTHANN }, + { "blackman", FILTER_BLACKMAN}, + { "nuttall", FILTER_NUTTALL }, + { "blackman-harris", FILTER_BLACKMANHARRIS }, + { "blackman-nuttall", FILTER_BLACKMANNUTTALL }, + { "flat-top", FILTER_FLATTOP }, + { "kaiser", FILTER_KAISER }, + { "parzen", FILTER_PARZEN }, + { "projection", FILTER_PROJECTION }, + { "sinogram", FILTER_SINOGRAM }, + { "rprojection", FILTER_RPROJECTION }, + { "rsinogram", FILTER_RSINOGRAM }, + { "none", FILTER_NONE }, + { 0, FILTER_ERROR } }; + + const FilterNameMapEntry *i; + + for (i = &map[0]; i->m_name; ++i) + if (stringCompareLowerCase(_filterType, i->m_name)) + return i->m_type; + + ASTRA_ERROR("Failed to convert \"%s\" into a filter.",_filterType); + + return FILTER_ERROR; +} + + + +} -- cgit v1.2.3