/**
* constructor to create a view
*
* @param projection: projection image as Grid2D
* @param radon: radon transformed and derived image as Grid2D
* @param projMatrix: projection matrix as Projection
*/
public View(Grid2D projection, Grid2D radon, Projection projMatrix) {
// Initialize center matrix //
CENTER = new SimpleMatrix(3, 4);
CENTER.setDiagValue(new SimpleVector(1.0, 1.0, 1.0));
// get data out of projection //
this.projectionWidth = projection.getWidth();
this.projectionHeight = projection.getHeight();
// get data out of radon transformed image //
this.radonWidth = radon.getWidth();
this.radonHeight = radon.getHeight();
this.projectionDiag =
Math.sqrt(projectionWidth * projectionWidth + projectionHeight * projectionHeight);
this.lineIncrement = radonWidth / projectionDiag;
this.angleIncrement = radonHeight / Math.PI;
// store radon transformed image //
this.radon = radon;
// get projection matrix P (3x4) //
this.P = SimpleOperators.multiplyMatrixProd(projMatrix.getK(), CENTER);
this.P = SimpleOperators.multiplyMatrixProd(this.P, projMatrix.getRt());
// get source position C (nullspace of the projection) //
DecompositionSVD decoP = new DecompositionSVD(this.P);
this.C = decoP.getV().getCol(3);
// normalize source vectors by last component //
// it is important that the last component is positive to have a positive center
// as it is defined in oriented projective geometry
this.C = this.C.dividedBy(this.C.getElement(3));
}
/**
* Creates the meshes of one single phase and adds it to the ArrayList of 4D meshes.
*
* @param phase
* @param parameters
* @param info
* @param splines
*/
private void createPhantom(
int phase, double[] parameters, CONRADCardiacModelConfig info, ArrayList<Mesh4D> splines) {
String pcaFile = heartBase + "\\CardiacModel\\phase_" + phase + ".ccm";
ActiveShapeModel asm = new ActiveShapeModel(pcaFile);
Mesh allComp = asm.getModel(parameters);
if (phase == 0) {
for (int i = 0; i < info.numAnatComp; i++) {
splines.add(new Mesh4D());
}
}
int count = 0;
for (heartComponents hc : heartComponents.values()) {
Mesh comp = new Mesh();
SimpleMatrix pts =
allComp
.getPoints()
.getSubMatrix(info.vertexOffs[count], 0, hc.getNumVertices(), info.vertexDim);
// rotate and translate points
for (int i = 0; i < pts.getRows(); i++) {
SimpleVector row = SimpleOperators.multiply(rot, pts.getRow(i));
row.add(trans);
pts.setRowValue(i, row);
}
comp.setPoints(pts);
comp.setConnectivity(
allComp
.getConnectivity()
.getSubMatrix(info.triangleOffs[count], 0, hc.getNumTriangles(), 3));
splines.get(count).addMesh(comp);
count++;
}
}
/**
* method to calculate a mapping K from two source positions C0, C1 to a plane C0 (C1) is the
* source position from the first (second) view
*/
public void createMappingToEpipolarPlane() {
// set up source matrices //
SimpleVector C0 = this.view1.C;
SimpleVector C1 = this.view2.C;
// compute Pluecker coordinates //
double L01 = C0.getElement(0) * C1.getElement(1) - C0.getElement(1) * C1.getElement(0);
double L02 = C0.getElement(0) * C1.getElement(2) - C0.getElement(2) * C1.getElement(0);
double L03 = C0.getElement(0) * C1.getElement(3) - C0.getElement(3) * C1.getElement(0);
double L12 = C0.getElement(1) * C1.getElement(2) - C0.getElement(2) * C1.getElement(1);
double L13 = C0.getElement(1) * C1.getElement(3) - C0.getElement(3) * C1.getElement(1);
double L23 = C0.getElement(2) * C1.getElement(3) - C0.getElement(3) * C1.getElement(2);
// construct B (6x1) //
SimpleVector B = new SimpleVector(L01, L02, L03, L12, L13, L23);
// compute infinity point in direction of B //
SimpleVector N = new SimpleVector(-L03, -L13, -L23, 0);
// compute plane E0 containing B and X0=(0,0,0,1) //
SimpleVector E0 = SimpleOperators.getPlueckerJoin(B, new SimpleVector(0, 0, 0, 1));
// find othonormal basis from plane normals //
// (vectors are of 3x1)
SimpleVector a2 = new SimpleVector(E0.getElement(0), E0.getElement(1), E0.getElement(2));
SimpleVector a3 = new SimpleVector(N.getElement(0), N.getElement(1), N.getElement(2));
// set vectors to unit length
a2.normalizeL2();
a3.normalizeL2();
// calculate cross product to get the last basis vector //
SimpleVector a1 = General.crossProduct(a2, a3).negated();
// (a1 is already of unit length -> no normalization needed)
// set up assembly matrix A (4x3) //
SimpleMatrix A = new SimpleMatrix(4, 3);
A.setSubColValue(0, 0, a1);
A.setSubColValue(0, 1, a2);
A.setSubColValue(0, 2, C0);
// store mapping matrix K (4x3 = 4x4 * 4x3) //
this.K = SimpleOperators.multiplyMatrixProd(SimpleOperators.getPlueckerMatrixDual(B), A);
}
@Override
public void workOnSlice(int sliceNumber) {
PrioritizableScene phantomScene = phantom;
if (phantom instanceof AnalyticPhantom4D) {
AnalyticPhantom4D scene4D = (AnalyticPhantom4D) phantom;
phantomScene = scene4D.getScene(((double) sliceNumber) / trajectory.getProjectionStackSize());
String disableAutoCenterBoolean =
Configuration.getGlobalConfiguration()
.getRegistryEntry(RegKeys.DISABLE_CENTERING_4DPHANTOM_PROJECTION_RENDERING);
boolean disableAutoCenter = false;
if (disableAutoCenterBoolean != null) {
disableAutoCenter = Boolean.parseBoolean(disableAutoCenterBoolean);
}
Translation centerTranslation = new Translation(new SimpleVector(0, 0, 0));
if (!disableAutoCenter) {
SimpleVector center =
SimpleOperators.add(
phantom.getMax().getAbstractVector(), phantom.getMin().getAbstractVector())
.dividedBy(2);
centerTranslation = new Translation(center.negated());
}
for (PhysicalObject o : phantomScene) {
o.getShape().applyTransform(centerTranslation);
// System.out.println(o.getShape().getMax() + " " + o.getShape().getMin());
// Translate a part of XCAT to the center of source & detector for 2D projection (e.g. knee
// at the center of the 2d projection)
String translationString =
Configuration.getGlobalConfiguration()
.getRegistryEntry(RegKeys.GLOBAL_TRANSLATION_4DPHANTOM_PROJECTION_RENDERING);
if (translationString != null) {
// Center b/w RKJC & LKJC: -292.6426 211.7856 440.7783 (subj 5, static60),-401.1700
// 165.9885 478.5600 (subj 2, static60)
// XCAT Center by min & max: -177.73999504606988, 179.8512744259873, 312.19713254613583
// translationVector = (XCAT Center by min & max) - (Center b/w RKJC & LKJC)=>
// 114.9026, -31.9343, -128.5811 (subj5), 120, 3, -110(subj2) Try 114.0568 2.4778
// -106.2550
String[] values = translationString.split(", ");
SimpleVector translationVector =
new SimpleVector(
Double.parseDouble(values[0]),
Double.parseDouble(values[1]),
Double.parseDouble(values[2]));
Translation translationToRotationCenter = new Translation(translationVector);
o.getShape().applyTransform(translationToRotationCenter);
}
}
// System.out.println(phantomScene.getMax() + " " + phantomScene.getMin());
}
Grid2D slice = raytraceScene(phantomScene, trajectory.getProjectionMatrix(sliceNumber));
this.imageBuffer.add(slice, sliceNumber);
}
private double[] compute2DCoordinates(double[] point3D, SimpleMatrix pMatrix) {
// Compute coordinates in projection data.
SimpleVector homogeneousPoint =
SimpleOperators.multiply(pMatrix, new SimpleVector(point3D[0], point3D[1], point3D[2], 1));
// Transform to 2D coordinates
double coordU = homogeneousPoint.getElement(0) / homogeneousPoint.getElement(2);
double coordV = homogeneousPoint.getElement(1) / homogeneousPoint.getElement(2);
// double pxlSize = config.getGeometry().getPixelDimensionX();
return new double[] {coordU, coordV};
}
/**
* method to compute the epipolar line integrals that state the epipolar consistency conditions by
* comparison of two views
*
* @param kappa_RAD: angle of epipolar plane
* @return double[] array containing two values (one for each view's line integral)
*/
public double[] computeEpipolarLineIntegrals(double kappa_RAD) {
// compute points on unit-circle (3x1) //
SimpleVector x_kappa = new SimpleVector(Math.cos(kappa_RAD), Math.sin(kappa_RAD), 1);
// compute epipolar plane E_kappa (4x1 = 4x3 * 3x1) //
SimpleVector E_kappa = SimpleOperators.multiply(this.K, x_kappa);
// compute line integral out of derived radon transform //
double value1 = view1.getValueByAlphaAndT(E_kappa);
double value2 = view2.getValueByAlphaAndT(E_kappa);
// both values are returned //
return new double[] {value1, value2};
}
/**
* Method to calculate alpha and t as indices from the radon transformed image of a view.
* Neccessary are the inverse projection image (as SimpleMatrix) and the epipolar plane E
*
* @param E: epipolar plane E as SimpleVector (4 entries)
* @return: line integral value as double
*/
private double getValueByAlphaAndT(SimpleVector E) {
// compute corresponding epipolar lines //
// (epipolar lines are of 3x1 = 3x4 * 4x1)
SimpleVector l_kappa = SimpleOperators.multiply(this.P_Inverse.transposed(), E);
// init the coordinate shift //
int t_u = this.projectionWidth / 2;
int t_v = this.projectionHeight / 2;
// compute angle alpha and distance to origin t //
double l0 = l_kappa.getElement(0);
double l1 = l_kappa.getElement(1);
double l2 = l_kappa.getElement(2);
double alpha_kappa_RAD = Math.atan2(-l0, l1) + Math.PI / 2;
double t_kappa = -l2 / Math.sqrt(l0 * l0 + l1 * l1);
// correct the coordinate shift //
t_kappa -= t_u * Math.cos(alpha_kappa_RAD) + t_v * Math.sin(alpha_kappa_RAD);
// correct some alpha falling out of the radon window //
if (alpha_kappa_RAD < 0) {
alpha_kappa_RAD *= -1.0;
} else if (alpha_kappa_RAD > Math.PI) {
alpha_kappa_RAD = 2.0 * Math.PI - alpha_kappa_RAD;
}
// write back to l_kappa //
l_kappa.setElementValue(0, Math.cos(alpha_kappa_RAD));
l_kappa.setElementValue(1, Math.sin(alpha_kappa_RAD));
l_kappa.setElementValue(2, -t_kappa);
// calculate x and y coordinates for derived radon transformed image //
double x = t_kappa * this.lineIncrement + 0.5 * this.radonWidth;
double y = alpha_kappa_RAD * this.angleIncrement;
// get intensity value out of radon transformed image //
// (interpolation needed)
return InterpolationOperators.interpolateLinear(this.radon, x, y);
}
public Grid2D raytraceScene(PrioritizableScene phantomScene, Projection projection) {
Trajectory geom = Configuration.getGlobalConfiguration().getGeometry();
// Grid2D slice = new Grid2D(geom.getDetectorWidth(), geom.getDetectorHeight());
Grid2D slice =
detector.createDetectorGrid(geom.getDetectorWidth(), geom.getDetectorHeight(), projection);
rayTracer.setScene(phantomScene);
// Second rule of optimization is: Optimize later.
PointND raySource = new PointND(0, 0, 0);
raySource.setCoordinates(projection.computeCameraCenter());
StraightLine castLine = new StraightLine(raySource, new SimpleVector(0, 0, 0));
SimpleVector centerPixDir = null;
if (accurate) {
centerPixDir = projection.computePrincipalAxis();
}
// SimpleVector prinpoint = trajectory.getProjectionMatrix(sliceNumber).getPrincipalPoint();
double xcorr = 0; // trajectory.getDetectorWidth()/2 - prinpoint.getElement(0);
double ycorr = 0; // trajectory.getDetectorHeight()/2 - prinpoint.getElement(1);
double length = trajectory.getSourceToDetectorDistance();
Edge environmentEdge = new Edge(new PointND(0), new PointND(length));
ArrayList<PhysicalObject> fallBackBackground = new ArrayList<PhysicalObject>(1);
SimpleVector pixel = new SimpleVector(0, 0);
boolean negate = false;
for (int y = 0; y < trajectory.getDetectorHeight(); y++) {
for (int x = 0; x < trajectory.getDetectorWidth(); x++) {
pixel.setElementValue(0, x - xcorr);
pixel.setElementValue(1, y - ycorr);
SimpleVector dir = projection.computeRayDirection(pixel);
if ((y == 0) && (x == 0)) {
// Check that ray direction is towards origin.
double max = 0;
int index = 0;
for (int i = 0; i < 3; i++) {
if (Math.abs(dir.getElement(i)) > max) {
max = Math.abs(dir.getElement(i));
index = i;
}
}
double t = -raySource.get(index) / dir.getElement(index);
if (t < 0) negate = true;
}
if (negate) dir.negate();
castLine.setDirection(dir);
ArrayList<PhysicalObject> segments = rayTracer.castRay(castLine);
if (accurate) {
double dirCosine = SimpleOperators.multiplyInnerProd(centerPixDir, dir);
length = trajectory.getSourceToDetectorDistance() / dirCosine;
}
if (segments == null) {
fallBackBackground.clear();
segments = fallBackBackground;
} else {
if (accurate) {
environmentEdge =
new Edge(new PointND(0), new PointND(length - getTotalSegmentsLength(segments)));
}
}
environment.setShape(environmentEdge);
segments.add(environment);
/* old code:
double integral = absorptionModel.evaluateLineIntegral(segments);
slice.putPixelValue(x, y, integral);
*/
detector.writeToDetector(slice, x, y, segments);
}
}
return slice;
}
public void setTrajectory(
int numProjectionMatrices,
double sourceToAxisDistance,
double averageAngularIncrement,
double detectorOffsetX,
double detectorOffsetY,
CameraAxisDirection uDirection,
CameraAxisDirection vDirection,
SimpleVector rotationAxis,
PointND rotationCenter,
double angleFirstProjection) {
this.projectionMatrices = new Projection[numProjectionMatrices];
this.primaryAngles = new double[numProjectionMatrices];
this.numProjectionMatrices = numProjectionMatrices;
this.sourceToAxisDistance = sourceToAxisDistance;
this.averageAngularIncrement = averageAngularIncrement;
this.detectorOffsetU = detectorOffsetX;
this.detectorOffsetV = detectorOffsetY;
double cosPhi = Math.cos(General.toRadians(angleFirstProjection));
double sinPhi = Math.sin(General.toRadians(angleFirstProjection));
SimpleMatrix rotMat = new SimpleMatrix(3, 3);
rotMat.setElementValue(0, 0, cosPhi);
rotMat.setElementValue(0, 1, sinPhi);
rotMat.setElementValue(1, 0, -sinPhi);
rotMat.setElementValue(1, 1, cosPhi);
rotMat.setElementValue(2, 2, 1);
SimpleVector centerToCameraIdealAtInitialAngle =
SimpleOperators.multiply(rotMat, new SimpleVector(sourceToAxisDistance, 0, 0));
Plane3D trajPlane =
new Plane3D(
rotationAxis,
SimpleOperators.multiplyInnerProd(rotationAxis, rotationCenter.getAbstractVector()));
double distToPlane = trajPlane.computeDistance(new PointND(centerToCameraIdealAtInitialAngle));
SimpleVector centerToCameraDir =
SimpleOperators.subtract(
SimpleOperators.add(
rotationAxis.multipliedBy(-1 * distToPlane), centerToCameraIdealAtInitialAngle),
rotationCenter.getAbstractVector());
centerToCameraDir.divideBy(centerToCameraDir.normL2());
SimpleVector centerToCameraInitialInPlane =
centerToCameraDir.multipliedBy(sourceToAxisDistance);
for (int i = 0; i < numProjectionMatrices; i++) {
primaryAngles[i] = i * averageAngularIncrement + angleFirstProjection;
// System.out.println(primaryAngles[i] + " " + averageAngularIncrement + " " +
// this.reconDimensions[0] + " " + this.reconDimensions[1]);
projectionMatrices[i] = new Projection();
double rotationAngle = General.toRadians(primaryAngles[i]);
projectionMatrices[i].setRtFromCircularTrajectory(
rotationCenter.getAbstractVector(),
rotationAxis,
sourceToAxisDistance,
centerToCameraInitialInPlane,
uDirection,
vDirection,
rotationAngle);
SimpleVector spacingUV = new SimpleVector(pixelDimensionX, pixelDimensionY);
SimpleVector sizeUV = new SimpleVector(detectorWidth, detectorHeight);
SimpleVector offset = new SimpleVector(detectorOffsetX, detectorOffsetY);
projectionMatrices[i].setKFromDistancesSpacingsSizeOffset(
sourceToDetectorDistance, spacingUV, sizeUV, offset, 1.0, 0);
}
this.projectionStackSize = numProjectionMatrices;
// System.out.println("Defined geometry with SDD " +sourceToDetectorDistance);
}
private void visualizeKleinNishina(double energyJoule) {
int gridWidth = 600;
int gridHeight = 500;
double maxAngle = 360;
Grid2D grid = new Grid2D(gridWidth, gridHeight);
FloatProcessor fp = new FloatProcessor(grid.getWidth(), grid.getHeight());
fp.setPixels(grid.getBuffer());
// find max value
double max = 0;
for (int i = 0; i < maxAngle; ++i) {
double value = XRayTracerSampling.comptonAngleProbability(energyJoule, Math.toRadians(i));
if (value > max) {
max = value;
}
}
fp.drawLine((int) 0, grid.getHeight() / 2, grid.getWidth(), grid.getHeight() / 2);
fp.drawLine(grid.getWidth() / 2, 0, grid.getWidth() / 2, grid.getHeight());
fp.drawOval((grid.getWidth() - grid.getHeight()) / 2, 0, grid.getHeight(), grid.getHeight());
double lastX = 0;
double lastY = 0;
// draw angle distribution
for (int i = 0; i < maxAngle; ++i) {
double value = XRayTracerSampling.comptonAngleProbability(energyJoule, Math.toRadians(i));
SimpleMatrix m = Rotations.createBasicZRotationMatrix(Math.toRadians(i));
SimpleVector v = new SimpleVector(((value / max) * ((double) grid.getHeight() / 2.d)), 0, 0);
SimpleVector r = SimpleOperators.multiply(m, v);
double x = grid.getWidth() / 2 + r.getElement(0);
double y = grid.getHeight() / 2 + r.getElement(1);
if (i > 0) fp.drawLine((int) lastX, (int) lastY, (int) x, (int) y);
lastX = x;
lastY = y;
}
grid.show(
"Normalized Klein-Nishina cross-section as a function of scatter angle ("
+ energyJoule / eV
+ "eV)");
grid = new Grid2D(gridWidth, gridHeight);
fp = new FloatProcessor(grid.getWidth(), grid.getHeight());
fp.setPixels(grid.getBuffer());
// draw histogram with rejection sampling of the klein-nishina
// distribution
int[] angles = new int[grid.getWidth()];
for (int i = 0; i < numSamples; ++i) {
double angle = Math.toDegrees(sampler.getComptonAngleTheta(energyJoule));
int pos = (int) (angle * grid.getWidth() / 360.d);
angles[pos] += 1;
}
double max2 = 0;
for (int i = 0; i < angles.length; ++i) {
if (angles[i] > max2) {
max2 = angles[i];
}
}
for (int i = 0; i < angles.length; ++i) {
double x = i;
double y = ((angles[i]) * (grid.getHeight() / (max2)));
fp.drawLine((int) x, (int) grid.getHeight(), (int) x, grid.getHeight() - (int) y);
}
// draw klein-nishina probability function
lastX = 0;
lastY = 0;
for (int i = 0; i < maxAngle; ++i) {
double value = XRayTracerSampling.comptonAngleProbability(energyJoule, Math.toRadians(i));
double x = (i * (grid.getWidth() / 360.f));
double y = grid.getHeight() - ((value) * (grid.getHeight() / (max)));
fp.drawLine((int) lastX, (int) lastY, (int) x, (int) y);
lastX = x;
lastY = y;
}
grid.show(
"Energy: " + energyJoule / eV + "eV; x-axis: angle[0-360]; y-axis: probability[0-max]");
}
