package edu.stanford.rsl.tutorial.truncation; import ij.ImageJ; import edu.stanford.rsl.apps.gui.Citeable; import edu.stanford.rsl.conrad.data.numeric.Grid2D; import edu.stanford.rsl.conrad.data.numeric.InterpolationOperators; import edu.stanford.rsl.tutorial.parallel.ParallelProjector2D; import edu.stanford.rsl.tutorial.phantoms.Phantom; /** * In this class we investigate the paper * Yu, H., Yang, J., Jiang, M., & Wang, G. (2009). Supplemental analysis on compressed sensing based interior tomography. Physics in Medicine and Biology, 54(18), N425–N432. doi:10.1088/0031-9155/54/18/N04.Supplemental * * The paper correctly derives that an artifact image whose projection inside the truncated area is zero while having a constant value inside the ROI must be filled with zero. * In the class we derive a class of antifact images that is filled with zero and has zero forward projections. * * @author akmaier * */ public class ConstantValueZeroArtifactImage extends Phantom implements Citeable { public String getBibtexCitation() { return "@article{Yu2009, \n"+ " author = {Yu, Hengyong and Yang, Jiansheng and Jiang, Ming and Wang, Ge},\n"+ " doi = {10.1088/0031-9155/54/18/N04.Supplemental},\n"+ " file = {:C$\backslash$:/Users/z002xsyz/Desktop/supplemental.pdf:pdf},\n"+ " institution = {CT Laboratory, Biomedical Imaging Division, VT-WFU School of Biomedical Engineering, Virginia Tech, Blacksburg, VA 24061, USA. hengyong-yu@ieee.org},\n"+ " journal = {Physics in Medicine and Biology},\n"+ " keywords = {artifact image,compressed sensing,computed tomography,ct,interior tomography,minimization,total variation},\n"+ " number = {18},\n"+ " pages = {N425--N432},\n"+ " publisher = {IOP Publishing},\n"+ " title = {{Supplemental analysis on compressed sensing based interior tomography.}},\n"+ " volume = {54},\n"+ " year = {2009}\n"+ " }"; } public String getMedlineCitation() { return "Yu, H., Yang, J., Jiang, M., & Wang, G. (2009). Supplemental analysis on compressed sensing based interior tomography. Physics in Medicine and Biology, 54(18), N425–N432. doi:10.1088/0031-9155/54/18/N04.Supplemental"; } public ConstantValueZeroArtifactImage (int sizeX, int truncationDiameter, float value){ super(sizeX, sizeX, "Constant Value Zero Projection Artifact Phantom " + truncationDiameter + " " + value); for (int i = 0; i<sizeX; i++){ double j = Math.sqrt(-Math.pow(i-sizeX/2.0, 2)+Math.pow((truncationDiameter+1)-sizeX/2.0, 2)); if (Double.isNaN(j)) continue; InterpolationOperators.addInterpolateLinear(this.getSubGrid(i), (sizeX/2.0 - j), -value); InterpolationOperators.addInterpolateLinear(this.getSubGrid(i), (sizeX/2.0 + j), -value); j = Math.sqrt(-Math.pow(i-sizeX/2.0, 2)+Math.pow(truncationDiameter-sizeX/2.0, 2)); if (Double.isNaN(j)) continue; InterpolationOperators.addInterpolateLinear(this.getSubGrid(i), (sizeX/2.0 - j), value); InterpolationOperators.addInterpolateLinear(this.getSubGrid(i), (sizeX/2.0 + j), value); } for (int i = 0; i<sizeX; i++){ double j = Math.sqrt(-Math.pow(i-sizeX/2.0, 2)+Math.pow((truncationDiameter+1)-sizeX/2.0, 2)); if (Double.isNaN(j)) continue; InterpolationOperators.addInterpolateLinear(this, i, (sizeX/2.0 - j), -value); InterpolationOperators.addInterpolateLinear(this, i, (sizeX/2.0 + j), -value); j = Math.sqrt(-Math.pow(i-sizeX/2.0, 2)+Math.pow(truncationDiameter-sizeX/2.0, 2)); if (Double.isNaN(j)) continue; InterpolationOperators.addInterpolateLinear(this, i, (sizeX/2.0 - j), value); InterpolationOperators.addInterpolateLinear(this, i, (sizeX/2.0 + j), value); } } public static void main(String [] args){ new ImageJ(); int numS = 400; double deltaS = 200.0 / 201.0; int numTheta = 360; int truncationSize = 100; ConstantValueZeroArtifactImage phantom = new ConstantValueZeroArtifactImage(numS, truncationSize, 200); phantom.show("Phantom"); ParallelProjector2D projector2d = new ParallelProjector2D(Math.PI, Math.PI/(numTheta-1), numS, deltaS); Grid2D sinogram = projector2d.projectRayDrivenCL(phantom); sinogram.show("Sinogram"); } } /* * Copyright (C) 2010-2014 Andreas Maier * CONRAD is developed as an Open Source project under the GNU General Public License (GPL). */