+bool
+Projections::convertFFTPolar (ImageFile& rIF, int iInterpolationID, int iZeropad)
+{
+#ifndef HAVE_FFTW
+ rIF.arrayDataClear();
+ return false;
+#else
+ unsigned int nx = rIF.nx();
+ unsigned int ny = rIF.ny();
+ ImageFileArray v = rIF.getArray();
+ if (! rIF.isComplex())
+ rIF.convertRealToComplex();
+ ImageFileArray vImag = rIF.getImaginaryArray();
+
+ if (! v || nx == 0 || ny == 0)
+ return false;
+
+ Projections* pProj = this;
+ if (m_geometry == Scanner::GEOMETRY_EQUIANGULAR || m_geometry == Scanner::GEOMETRY_EQUILINEAR)
+ pProj = interpolateToParallel();
+
+ int iInterpDet = static_cast<int>(static_cast<double>(sqrt(nx*nx+ny*ny)));
+ int iNumInterpDetWithZeros = ProcessSignal::addZeropadFactor (iInterpDet, iZeropad);
+ double dProjScale = iInterpDet / (pProj->viewDiameter() * 0.05);
+ double dZeropadRatio = static_cast<double>(iNumInterpDetWithZeros) / static_cast<double>(iInterpDet);
+
+ fftw_complex* pcIn = static_cast<fftw_complex*> (fftw_malloc (sizeof(fftw_complex) * iNumInterpDetWithZeros));
+ fftw_plan plan = fftw_plan_dft_1d (iNumInterpDetWithZeros, pcIn, pcIn, FFTW_FORWARD, FFTW_ESTIMATE);
+
+ std::complex<double>** ppcDetValue = new std::complex<double>* [pProj->m_nView];
+ //double dInterpScale = (pProj->m_nDet-1) / static_cast<double>(iInterpDet-1);
+ double dInterpScale = pProj->m_nDet / static_cast<double>(iInterpDet);
+
+ double dFFTScale = 1. / static_cast<double>(iInterpDet * iInterpDet);
+ int iMidPoint = iInterpDet / 2;
+ double dMidPoint = static_cast<double>(iInterpDet) / 2.;
+ int iZerosAdded = iNumInterpDetWithZeros - iInterpDet;
+
+ // For each view, interpolate, shift to center at origin, and FFT
+ for (int iView = 0; iView < m_nView; iView++) {
+ DetectorValue* detval = pProj->getDetectorArray(iView).detValues();
+ LinearInterpolator<DetectorValue> projInterp (detval, pProj->m_nDet);
+ for (int iDet = 0; iDet < iInterpDet; iDet++) {
+ double dInterpPos = (m_nDet / 2.) + (iDet - dMidPoint) * dInterpScale;
+ pcIn[iDet][0] = projInterp.interpolate (dInterpPos) * dProjScale;
+ pcIn[iDet][1] = 0;
+ }
+
+ Fourier::shuffleFourierToNaturalOrder (pcIn, iInterpDet);
+ if (iZerosAdded > 0) {
+ for (int iDet1 = iInterpDet -1; iDet1 >= iMidPoint; iDet1--) {
+ pcIn[iDet1+iZerosAdded][0] = pcIn[iDet1][0];
+ pcIn[iDet1+iZerosAdded][1] = pcIn[iDet1][1];
+ }
+ for (int iDet2 = iMidPoint; iDet2 < iMidPoint + iZerosAdded; iDet2++)
+ pcIn[iDet2][0] = pcIn[iDet2][1] = 0;
+ }
+
+ fftw_execute (plan);
+
+ ppcDetValue[iView] = new std::complex<double> [iNumInterpDetWithZeros];
+ for (int iD = 0; iD < iNumInterpDetWithZeros; iD++) {
+ ppcDetValue[iView][iD] = std::complex<double> (pcIn[iD][0] * dFFTScale, pcIn[iD][1] * dFFTScale);
+ }
+
+ Fourier::shuffleFourierToNaturalOrder (ppcDetValue[iView], iNumInterpDetWithZeros);
+ }
+ fftw_free(pcIn) ;
+
+ fftw_destroy_plan (plan);
+
+ Array2d<double> adView (nx, ny);
+ Array2d<double> adDet (nx, ny);
+ double** ppdView = adView.getArray();
+ double** ppdDet = adDet.getArray();
+ pProj->calcArrayPolarCoordinates (nx, ny, ppdView, ppdDet, iNumInterpDetWithZeros, dZeropadRatio,
+ pProj->m_detInc * dInterpScale);
+
+ pProj->interpolatePolar (v, vImag, nx, ny, ppcDetValue, ppdView, ppdDet, pProj->m_nView, pProj->m_nDet,
+ iNumInterpDetWithZeros, iInterpolationID);
+
+ if (m_geometry == Scanner::GEOMETRY_EQUIANGULAR || m_geometry == Scanner::GEOMETRY_EQUILINEAR)
+ delete pProj;
+
+ for (int i = 0; i < m_nView; i++)
+ delete [] ppcDetValue[i];
+ delete [] ppcDetValue;
+
+ return true;
+#endif
+}
+
+
+void
+Projections::calcArrayPolarCoordinates (unsigned int nx, unsigned int ny, double** ppdView, double** ppdDet,
+ int iNumDetWithZeros, double dZeropadRatio, double dDetInc)
+{
+ double dLength = viewDiameter();
+ double xMin = -dLength / 2;
+ double xMax = xMin + dLength;
+ double yMin = -dLength / 2;
+ double yMax = yMin + dLength;
+ double xCent = (xMin + xMax) / 2;
+ double yCent = (yMin + yMax) / 2;
+
+ xMin = (xMin - xCent) * dZeropadRatio + xCent;
+ xMax = (xMax - xCent) * dZeropadRatio + xCent;
+ yMin = (yMin - yCent) * dZeropadRatio + yCent;
+ yMax = (yMax - yCent) * dZeropadRatio + yCent;
+
+ double xInc = (xMax - xMin) / nx; // size of cells
+ double yInc = (yMax - yMin) / ny;
+
+ double dDetCenter = (iNumDetWithZeros - 1) / 2.; // index refering to L=0 projection
+ // +1 is correct for frequency data, ndet-1 is correct for projections
+ // if (isEven (iNumDetWithZeros))
+ // dDetCenter = (iNumDetWithZeros + 0) / 2;
+
+ // Calculates polar coordinates (view#, det#) for each point on phantom grid
+ double x = xMin + xInc / 2; // Rectang coords of center of pixel
+ for (unsigned int ix = 0; ix < nx; x += xInc, ix++) {
+ double y = yMin + yInc / 2;
+ for (unsigned int iy = 0; iy < ny; y += yInc, iy++) {
+ double r = ::sqrt (x * x + y * y);
+ double phi = atan2 (y, x);
+
+ if (phi <= -m_rotInc / 2)
+ phi += TWOPI;
+ if (phi >= PI - (m_rotInc / 2)) {
+ phi -= PI;
+ r = -r;
+ }
+
+ ppdView[ix][iy] = (phi - m_rotStart) / m_rotInc;
+ ppdDet[ix][iy] = (r / dDetInc) + dDetCenter;
+ }
+ }
+}
+
+void
+Projections::interpolatePolar (ImageFileArray& v, ImageFileArray& vImag,
+ unsigned int nx, unsigned int ny, std::complex<double>** ppcDetValue, double** ppdView,
+ double** ppdDet, unsigned int nView, unsigned int nDet, unsigned int nDetWithZeros, int iInterpolationID)
+{
+ typedef std::complex<double> complexValue;
+
+ BilinearPolarInterpolator<complexValue>* pBilinear = NULL;
+ BicubicPolyInterpolator<complexValue>* pBicubic = NULL;
+ if (iInterpolationID == POLAR_INTERP_BILINEAR)
+ pBilinear = new BilinearPolarInterpolator<complexValue> (ppcDetValue, nView, nDetWithZeros);
+ else if (iInterpolationID == POLAR_INTERP_BICUBIC)
+ pBicubic = new BicubicPolyInterpolator<complexValue> (ppcDetValue, nView, nDetWithZeros);
+
+ for (unsigned int ix = 0; ix < ny; ix++) {
+ for (unsigned int iy = 0; iy < ny; iy++) {
+ if (iInterpolationID == POLAR_INTERP_NEAREST) {
+ unsigned int iView = nearest<int> (ppdView[ix][iy]);
+ unsigned int iDet = nearest<int> (ppdDet[ix][iy]);
+ if (iView == nView)
+ iView = 0;
+ if (iDet >= 0 && iDet < nDetWithZeros && iView >= 0 && iView < nView) {
+ v[ix][iy] = ppcDetValue[iView][iDet].real();
+ if (vImag)
+ vImag[ix][iy] = ppcDetValue[iView][iDet].imag();
+ } else {
+ v[ix][iy] = 0;
+ if (vImag)
+ vImag[ix][iy] = 0;
+ }
+
+ } else if (iInterpolationID == POLAR_INTERP_BILINEAR) {
+ std::complex<double> vInterp = pBilinear->interpolate (ppdView[ix][iy], ppdDet[ix][iy]);
+ v[ix][iy] = vInterp.real();
+ if (vImag)
+ vImag[ix][iy] = vInterp.imag();
+ } else if (iInterpolationID == POLAR_INTERP_BICUBIC) {
+ std::complex<double> vInterp = pBicubic->interpolate (ppdView[ix][iy], ppdDet[ix][iy]);
+ v[ix][iy] = vInterp.real();
+ if (vImag)
+ vImag[ix][iy] = vInterp.imag();
+ }
+ }
+ }
+}
+
+bool
+Projections::initFromSomatomAR_STAR (int iNViews, int iNDets, unsigned char* pData, unsigned long lDataLength)
+{
+ init (iNViews, iNDets);
+ m_geometry = Scanner::GEOMETRY_EQUIANGULAR;
+ m_dFocalLength = 510;
+ m_dSourceDetectorLength = 890;
+ m_detInc = convertDegreesToRadians (3.06976 / 60);
+ m_dFanBeamAngle = iNDets * m_detInc;
+ m_detStart = -(m_dFanBeamAngle / 2);
+ m_rotInc = TWOPI / static_cast<double>(iNViews);
+ m_rotStart = 0;
+ m_dViewDiameter = sin (m_dFanBeamAngle / 2) * m_dFocalLength * 2;
+
+ if (! ((iNViews == 750 && lDataLength == 1560000L) || (iNViews == 950 && lDataLength == 1976000L)
+ || (iNViews == 1500 && lDataLength == 3120000)))
+ return false;
+
+ double dCenter = (iNDets - 1.) / 2.; // change from (Nm+1)/2 because of 0 vs. 1 indexing
+ double* pdCosScale = new double [iNDets];
+ for (int i = 0; i < iNDets; i++)
+ pdCosScale[i] = 1. / cos ((i - dCenter) * m_detInc);
+
+ long lDataPos = 0;
+ for (int iv = 0; iv < iNViews; iv++) {
+ unsigned char* pArgBase = pData + lDataPos;
+ unsigned char* p = pArgBase+0; SwapBytes4IfLittleEndian (p);
+ // long lProjNumber = *reinterpret_cast<long*>(p);
+
+ p = pArgBase+20; SwapBytes4IfLittleEndian (p);
+ long lEscale = *reinterpret_cast<long*>(p);
+
+ p = pArgBase+28; SwapBytes4IfLittleEndian (p);
+ // long lTime = *reinterpret_cast<long*>(p);
+
+ p = pArgBase + 4; SwapBytes4IfLittleEndian (p);
+ double dAlpha = *reinterpret_cast<float*>(p) + HALFPI;
+
+ p = pArgBase+12; SwapBytes4IfLittleEndian (p);
+ // double dAlign = *reinterpret_cast<float*>(p);