+++ /dev/null
-/*****************************************************************************
-** FILE IDENTIFICATION
-**
-** Name: rec_t.c Image Reconstruction Procedures
-** Programmer: Kevin Rosenberg
-** Date Started: Aug 84
-**
-** GLOBAL FUNCTIONS
-** proj_reconst() Reconstruct Image from Projections
-**
-** This is part of the CTSim program
-** Copyright (C) 1983-2000 Kevin Rosenberg
-**
-** $Id: reconstr.cpp,v 1.2 2000/06/20 17:54:51 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
-** 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 "ct.h"
-
-
-/* NAME
- * proj_reconst Reconstruct Image from Projections
- *
- * SYNOPSIS
- * im = proj_reconst (im, proj, filt_type, filt_param, interp_type)
- * IMAGE *im Output image
- * RAYSUM *proj Raysum data if in memory
- * int filt_type Type of convolution filter to use
- * double filt_param Filter specific parameter
- * Currently, used only with Hamming filters
- * int interp_type Type of interpolation method to use
- *
- * ALGORITHM
- *
- * Calculate one-dimensional filter in spatial domain
- * Allocate & clear (zero) the 2d output image array
- * For each projection view
- * Convolve raysum array with filter
- * Backproject raysums and add (summate) to image array
- * end
- */
-
-ImageFile&
-proj_reconst (ImageFile& im, Projections& proj, const FilterType filt_type, double filt_param, InterpolationType interp_type, int interp_param, const BackprojType backproj_type, const int trace)
-{
- int ndet = proj.nDet();
- int nview = proj.nView();
- double det_inc = proj.detInc();
- double detlen = (ndet - 1) * det_inc;
- int n_filtered_proj = ndet;
- double filtered_proj [n_filtered_proj]; // convolved result
-
-#ifdef HAVE_BSPLINE_INTERP
- int spline_order = 0, zoom_factor = 0;
- if (interp_type == I_BSPLINE) {
- zoom_factor = interp_param;
- spline_order = 3;
- zoom_factor = 3;
- n_filtered_proj = (ndet - 1) * (zoom_factor + 1) + 1;
- }
-#endif
-
- int n_vec_filter = 2 * ndet - 1;
- double filterBW = 1. / det_inc;
- double filterMin = -detlen;
- double filterMax = detlen;
-
- SignalFilter filter (filt_type, filterBW, filterMin, filterMax, n_vec_filter, filt_param, D_SPATIAL, 0);
-
-#if HAVE_SGP
- SGP_ID gid;
- double plot_xaxis [n_vec_filter]; // array for plotting
-
- if (trace > TRACE_TEXT) {
- int i;
- double f;
- double filterInc = (filterMax - filterMin) / (n_vec_filter - 1);
- for (i = 0, f = filterMin; i < n_vec_filter; i++, f += filterInc)
- plot_xaxis[i] = f;
-
- gid = ezplot (plot_xaxis, filter.getFilter(), n_vec_filter);
- cio_put_str ("Press any key to continue");
- cio_kb_getc ();
- sgp2_close (gid);
- }
- if (trace >= TRACE_TEXT) {
- printf ("nview=%d, ndet=%d, det_start=%.4f, det_inc=%.4f\n", proj.nView(), proj.nDet(), proj.detStart(), proj.detInc());
- }
-#endif //HAVE_SGP
-
- Backproject* bj = selectBackprojector (backproj_type, proj, im, interp_type);
-
- for (int iview = 0; iview < nview; iview++) {
- if (trace >= TRACE_TEXT)
- printf ("Reconstructing view %d (last = %d)\n", iview, nview - 1);
-
- DetectorArray& darray = proj.getDetectorArray (iview);
- DetectorValue* detval = darray.detValues();
-
- for (int j = 0; j < ndet; j++)
- filtered_proj[j] = filter.convolve (detval, det_inc, j, ndet, FUNC_BOTH);
-
-#ifdef HAVE_SGP
- if (trace >= TRACE_PLOT) {
- ezset ("clear.");
- ezset ("xticks major 5.");
- ezset ("xlabel ");
- ezset ("ylabel ");
- ezset ("xlength .5.");
- ezset ("box.");
- ezset ("grid.");
- ezset ("ufinish yes.");
- ezplot (detval, plot_xaxis, proj.nDet());
- ezset ("clear.");
- ezset ("xticks major 5.");
- ezset ("xlabel ");
- ezset ("ylabel ");
- ezset ("ustart yes.");
- ezset ("xporigin .5.");
- ezset ("xlength .5.");
- ezset ("box");
- ezset ("grid");
- gid = ezplot (filtered_proj, plot_xaxis, proj.nDet());
- }
-#endif //HAVE_SGP
-
-#ifdef HAVE_BSPLINE_INTERP
- if (interp_type == I_BSPLINE)
- bspline (proj.nDet(), zoom_factor, spline_order, filtered_proj, filtered_proj);
-
-#ifdef HAVE_SGP
- if (trace >= TRACE_PLOT && interp_type == I_BSPLINE) {
- bspline (proj.nDet(), zoom_factor, spline_order, filtered_proj, filtered_proj);
- ezplot_1d (filtered_proj, n_filtered_proj);
- }
-#endif
-#endif
-
- bj->BackprojectView (filtered_proj, darray.viewAngle());
-
-#ifdef HAVE_SGP
- if (trace >= TRACE_PLOT) {
- char str[256];
- printf ("Do you want to exit with current pic (y/n) -- ");
- fgets(str, sizeof(str), stdin);
- sgp2_close (sgp2_get_active_win());
- if (tolower(str[0]) == 'y') {
- break;
- }
- }
-#endif //HAVE_SGP
- }
-
- delete bj;
-
- return (im);
-}
-
projects / ctsim.git / blobdiff