-/*****************************************************************************\r
-** FILE IDENTIFICATION\r
-**\r
-** Name: fourier.h\r
-** Purpose: Header for Fourier transform functions\r
-** Programmer: Kevin Rosenberg\r
-** Date Started: Dec 2000\r
-**\r
-** This is part of the CTSim program\r
-** Copyright (C) 1983-2001 Kevin Rosenberg\r
-**\r
-** $Id: fourier.h,v 1.1 2001/01/02 06:33:04 kevin Exp $\r
-**\r
-** This program is free software; you can redistribute it and/or modify\r
-** it under the terms of the GNU General Public License (version 2) as\r
-** published by the Free Software Foundation.\r
-**\r
-** This program is distributed in the hope that it will be useful,\r
-** but WITHOUT ANY WARRANTY; without even the implied warranty of\r
-** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the\r
-** GNU General Public License for more details.\r
-**\r
-** You should have received a copy of the GNU General Public License\r
-** along with this program; if not, write to the Free Software\r
-** Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA\r
-******************************************************************************/\r
-\r
-#include <complex>\r
-\r
-class ImageFile;\r
-\r
-class Fourier {\r
-public:\r
- static void shuffleFourierToNaturalOrder (ImageFile& im);\r
- static void shuffleNaturalToFourierOrder (ImageFile& im);\r
-\r
- static void shuffleNaturalToFourierOrder (float* pdVector, const int n);\r
- static void shuffleNaturalToFourierOrder (double* pdVector, const int n);\r
- static void shuffleNaturalToFourierOrder (std::complex<double>* pdVector, const int n);\r
- static void shuffleFourierToNaturalOrder (float* pdVector, const int n);\r
- static void shuffleFourierToNaturalOrder (double* pdVector, const int n);\r
- static void shuffleFourierToNaturalOrder (std::complex<double>* pdVector, const int n);\r
-\r
-}; // namespace Fourier\r
-\r
+/*****************************************************************************
+** FILE IDENTIFICATION
+**
+** Name: fourier.h
+** Purpose: Header for Fourier transform functions
+** Programmer: Kevin Rosenberg
+** Date Started: Dec 2000
+**
+** This is part of the CTSim program
+** Copyright (c) 1983-2001 Kevin Rosenberg
+**
+** $Id$
+**
+** 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
+** published by the Free Software Foundation.
+**
+** This program 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 this program; if not, write to the Free Software
+** Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+******************************************************************************/
+
+#include <complex>
+#ifdef HAVE_FFTW
+#include <fftw3.h>
+#endif
+
+class ImageFile;
+
+class Fourier {
+public:
+ static void shuffleFourierToNaturalOrder (ImageFile& im);
+ static void shuffleNaturalToFourierOrder (ImageFile& im);
+
+#ifdef HAVE_FFTW
+ static void shuffleFourierToNaturalOrder (fftw_complex* pc, const int n);
+ static void shuffleNaturalToFourierOrder (fftw_complex* pc, const int n);
+#endif
+
+// Odd Number of Points
+// Natural Frequency Order: -(n-1)/2...-1,0,1...(n-1)/2
+// Fourier Frequency Order: 0, 1..(n-1)/2,-(n-1)/2...-1
+// Even Number of Points
+// Natural Frequency Order: -n/2...-1,0,1...((n/2)-1)
+// Fourier Frequency Order: 0,1...((n/2)-1),-n/2...-1
+ template<class T>
+ static void shuffleNaturalToFourierOrder (T* pVector, const int n)
+ {
+ T* pTemp = new T [n];
+ int i;
+ if (isOdd(n)) { // Odd
+ int iHalfN = (n - 1) / 2;
+
+ pTemp[0] = pVector[iHalfN];
+ for (i = 0; i < iHalfN; i++)
+ pTemp[i + 1] = pVector[i + 1 + iHalfN];
+ for (i = 0; i < iHalfN; i++)
+ pTemp[i + iHalfN + 1] = pVector[i];
+ } else { // Even
+ int iHalfN = n / 2;
+ pTemp[0] = pVector[iHalfN];
+ for (i = 0; i < iHalfN - 1; i++)
+ pTemp[i + 1] = pVector[i + iHalfN + 1];
+ for (i = 0; i < iHalfN; i++)
+ pTemp[i + iHalfN] = pVector[i];
+ }
+
+ for (i = 0; i < n; i++)
+ pVector[i] = pTemp[i];
+ delete pTemp;
+ }
+
+ template<class T>
+ static void shuffleFourierToNaturalOrder (T* pVector, const int n)
+ {
+ T* pTemp = new T [n];
+ int i;
+ if (isOdd(n)) { // Odd
+ int iHalfN = (n - 1) / 2;
+
+ pTemp[iHalfN] = pVector[0];
+ for (i = 0; i < iHalfN; i++)
+ pTemp[i + 1 + iHalfN] = pVector[i + 1];
+ for (i = 0; i < iHalfN; i++)
+ pTemp[i] = pVector[i + iHalfN + 1];
+ } else { // Even
+ int iHalfN = n / 2;
+ pTemp[iHalfN] = pVector[0];
+ for (i = 0; i < iHalfN; i++)
+ pTemp[i] = pVector[i + iHalfN];
+ for (i = 0; i < iHalfN - 1; i++)
+ pTemp[i + iHalfN + 1] = pVector[i+1];
+ }
+
+ for (i = 0; i < n; i++)
+ pVector[i] = pTemp[i];
+ delete pTemp;
+ }
+#if 0
+ static void shuffleNaturalToFourierOrder (float* pdVector, const int n);
+ static void shuffleNaturalToFourierOrder (double* pdVector, const int n);
+ static void shuffleNaturalToFourierOrder (std::complex<double>* pdVector, const int n);
+ static void shuffleFourierToNaturalOrder (float* pdVector, const int n);
+ static void shuffleFourierToNaturalOrder (double* pdVector, const int n);
+ static void shuffleFourierToNaturalOrder (std::complex<double>* pdVector, const int n);
+#endif
+};
+
+
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