/**
* Merge two clusters in the cluster list for given cluster indices.
*
* @param clusterCenterList The list of cluster centers.
* @param clusterPair Indices of the two clusters to merge.
*/
private static void mergeClusters(
final java.util.List<ClusterInfo> clusterCenterList, final int[] clusterPair) {
final int idx1 = clusterPair[0];
final int idx2 = clusterPair[1];
final int size1 = clusterCenterList.get(idx1).size;
final int size2 = clusterCenterList.get(idx2).size;
final int newClusterSize = size1 + size2;
final double[][] newCenterRe = new double[3][3];
final double[][] newCenterIm = new double[3][3];
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++) {
newCenterRe[i][j] =
(size1 * clusterCenterList.get(idx1).centerRe[i][j]
+ size2 * clusterCenterList.get(idx2).centerRe[i][j])
/ newClusterSize;
newCenterIm[i][j] =
(size1 * clusterCenterList.get(idx1).centerIm[i][j]
+ size2 * clusterCenterList.get(idx2).centerIm[i][j])
/ newClusterSize;
}
}
if (idx1 < idx2) {
clusterCenterList.remove(idx2);
clusterCenterList.remove(idx1);
} else {
clusterCenterList.remove(idx1);
clusterCenterList.remove(idx2);
}
ClusterInfo clusterCenter = new ClusterInfo();
clusterCenter.setClusterCenter(
clusterCenterList.size(), newCenterRe, newCenterIm, newClusterSize);
clusterCenterList.add(clusterCenter);
}
/**
* Compute the centers of the 90 clusters in the 3 categories.
*
* @param srcBandList the input bands
* @param tileRectangles Array of rectangles for all source tiles of the image
* @param op the operator
*/
private void getClusterCenters(
final java.util.List<ClusterInfo> pvCenterList,
final java.util.List<ClusterInfo> pdCenterList,
final java.util.List<ClusterInfo> psCenterList,
final PolBandUtils.PolSourceBand srcBandList,
final Rectangle[] tileRectangles,
final PolarimetricClassificationOp op) {
final StatusProgressMonitor status =
new StatusProgressMonitor(StatusProgressMonitor.TYPE.SUBTASK);
status.beginTask("Computing Initial Cluster Centres... ", tileRectangles.length);
final ThreadManager threadManager = new ThreadManager();
final double[][][] pvSumRe = new double[numInitialClusters][3][3];
final double[][][] pvSumIm = new double[numInitialClusters][3][3];
final double[][][] pdSumRe = new double[numInitialClusters][3][3];
final double[][][] pdSumIm = new double[numInitialClusters][3][3];
final double[][][] psSumRe = new double[numInitialClusters][3][3];
final double[][][] psSumIm = new double[numInitialClusters][3][3];
// counter for the number of pixels in each cluster in the 3 categories: vol, dbl, suf
final int[][] clusterCounter = new int[3][numInitialClusters];
try {
for (final Rectangle rectangle : tileRectangles) {
op.checkIfCancelled();
final Thread worker =
new Thread() {
final Tile[] sourceTiles = new Tile[srcBandList.srcBands.length];
final ProductData[] dataBuffers = new ProductData[srcBandList.srcBands.length];
final double[][] Sr = new double[2][2];
final double[][] Si = new double[2][2];
final double[][] Tr = new double[3][3];
final double[][] Ti = new double[3][3];
@Override
public void run() {
final int x0 = rectangle.x;
final int y0 = rectangle.y;
final int w = rectangle.width;
final int h = rectangle.height;
final int xMax = x0 + w;
final int yMax = y0 + h;
// System.out.println("x0 = " + x0 + ", y0 = " + y0 + ", w = " + w + ", h = " + h);
for (int i = 0; i < sourceTiles.length; ++i) {
sourceTiles[i] = op.getSourceTile(srcBandList.srcBands[i], rectangle);
dataBuffers[i] = sourceTiles[i].getDataBuffer();
}
final TileIndex srcIndex = new TileIndex(sourceTiles[0]);
for (int y = y0; y < yMax; ++y) {
srcIndex.calculateStride(y);
for (int x = x0; x < xMax; ++x) {
PolOpUtils.getT3(srcIndex.getIndex(x), sourceProductType, dataBuffers, Tr, Ti);
synchronized (clusterCounter) {
int clusterIdx;
if (mask[y][x] < -64) { // pv
clusterIdx = mask[y][x] + 128;
computeSummationOfT3(clusterIdx + 1, Tr, Ti, pvSumRe, pvSumIm);
clusterCounter[0][clusterIdx]++;
} else if (mask[y][x] < 0) { // pd
clusterIdx = mask[y][x] + 64;
computeSummationOfT3(clusterIdx + 1, Tr, Ti, pdSumRe, pdSumIm);
clusterCounter[1][clusterIdx]++;
} else if (mask[y][x] < 64) { // ps
clusterIdx = mask[y][x];
computeSummationOfT3(clusterIdx + 1, Tr, Ti, psSumRe, psSumIm);
clusterCounter[2][clusterIdx]++;
}
}
}
}
}
};
threadManager.add(worker);
status.worked(1);
}
threadManager.finish();
} catch (Throwable e) {
OperatorUtils.catchOperatorException(op.getId() + " getClusterCenters ", e);
} finally {
status.done();
}
// compute centers for all 90 clusters
for (int c = 0; c < numInitialClusters; c++) {
double[][] centerRe = new double[3][3];
double[][] centerIm = new double[3][3];
if (clusterCounter[0][c] > 0) {
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++) {
centerRe[i][j] = pvSumRe[c][i][j] / clusterCounter[0][c];
centerIm[i][j] = pvSumIm[c][i][j] / clusterCounter[0][c];
}
}
ClusterInfo clusterCenter = new ClusterInfo();
clusterCenter.setClusterCenter(c, centerRe, centerIm, clusterCounter[0][c]);
pvCenterList.add(clusterCenter);
}
if (clusterCounter[1][c] > 0) {
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++) {
centerRe[i][j] = pdSumRe[c][i][j] / clusterCounter[1][c];
centerIm[i][j] = pdSumIm[c][i][j] / clusterCounter[1][c];
}
}
ClusterInfo clusterCenter = new ClusterInfo();
clusterCenter.setClusterCenter(c, centerRe, centerIm, clusterCounter[1][c]);
pdCenterList.add(clusterCenter);
}
if (clusterCounter[2][c] > 0) {
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++) {
centerRe[i][j] = psSumRe[c][i][j] / clusterCounter[2][c];
centerIm[i][j] = psSumIm[c][i][j] / clusterCounter[2][c];
}
}
ClusterInfo clusterCenter = new ClusterInfo();
clusterCenter.setClusterCenter(c, centerRe, centerIm, clusterCounter[2][c]);
psCenterList.add(clusterCenter);
}
}
}