@Override
public Grid2D applyToolToImage(Grid2D imageProcessor) throws Exception {
Grid2D secondImageProcessor = imageProcessor;
Grid2D firstImageProcessor = hardMaterial.getSubGrid(imageIndex);
int xoffset = (firstImageProcessor.getWidth() - secondImageProcessor.getWidth()) / 2;
int yoffset = (firstImageProcessor.getHeight() - secondImageProcessor.getHeight()) / 2;
for (int i = 0; i < firstImageProcessor.getWidth(); i++) {
for (int j = 0; j < firstImageProcessor.getHeight(); j++) {
double value =
slope
* InterpolationOperators.interpolateLinear(
firstImageProcessor,
i + projectionXShift + xoffset,
j + projectionYShift + yoffset);
double value2 = secondImageProcessor.getPixelValue(i, j);
double lambda = lambda0;
try {
if (value > 0.02) {
lambda = lut.getValue(value2, value);
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
secondImageProcessor.putPixelValue(i, j, value2 + (lambda0 - lambda) * value);
}
}
return secondImageProcessor;
}
/**
* 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 createSinogramm(Grid2D phantom, boolean filter) {
// Bouding Box
Box imageBox =
new Box(
phantom.getWidth() * phantom.getSpacing()[0],
phantom.getHeight() * phantom.getSpacing()[1],
2.0d);
imageBox.setLowerCorner(new PointND(phantom.getOrigin()[0], phantom.getOrigin()[1], -1.0));
imageBox.setUpperCorner(new PointND(-phantom.getOrigin()[0], -phantom.getOrigin()[1], 1.0));
// walk over each projection
for (int indexProjections = 0; indexProjections < projections; indexProjections++) {
// walk along the detector
for (int indexDetektor = 0; indexDetektor < numberPixel; indexDetektor++) {
// define the parallel lines of the detector
double[] indexWorld = this.indexToPhysical(indexDetektor, indexProjections);
double angle = angleWidthR * indexProjections;
double s = indexWorld[0];
double cos = Math.cos(angle);
double sin = Math.sin(angle);
PointND p1 = new PointND(cos * s, sin * s, 0.0d);
PointND p2 = new PointND(cos * s - sin, sin * s + cos, 0.0d);
StraightLine line = new StraightLine(p1, p2);
// intersection of the box and the line
ArrayList<PointND> crossingPoints = imageBox.intersect(line);
// if there is no intersection -> change direction of the line and look again
if (crossingPoints.size() == 0) {
p2 = new PointND(cos * s + sin, sin * s - cos, 0.0d);
line = new StraightLine(p1, p2);
crossingPoints = imageBox.intersect(line);
}
if (crossingPoints.size() == 2) {
PointND c1 = crossingPoints.get(0);
PointND c2 = crossingPoints.get(1);
// compute distance between intersectoin points
double distance = c1.euclideanDistance(c2);
// define the direction of the line
double deltax = (c2.get(0) - c1.get(0)) / (distance);
double deltay = (c2.get(1) - c1.get(1)) / (distance);
double deltaz = (c2.get(2) - c1.get(2)) / (distance);
PointND richtung = new PointND(deltax, deltay, deltaz);
// result value at the current position in the sinogramm
float val = 0.f;
// stepsize of the integral
double delta = 0.5; // in mm
// line integral
for (double k = 0; k < (distance); k = k + delta) {
double indexX = c1.get(0) + k * (richtung.get(0));
double indexY = c1.get(1) + k * (richtung.get(1));
double[] indexImage = phantom.physicalToIndex(indexX, indexY);
val += InterpolationOperators.interpolateLinear(phantom, indexImage[0], indexImage[1]);
}
this.setAtIndex(indexDetektor, indexProjections, (float) (val * delta));
}
}
}
if (filter == true) {
filtering(this);
}
Grid2D result = new Grid2D(this);
return result;
}
