public static int identify_R_U(Mat binary) {
// 0: hull points identified < 2
// 1: R
// 2: U
List<MatOfPoint> contours = new ArrayList<MatOfPoint>();
List<MatOfPoint> hullPoints = new ArrayList<MatOfPoint>();
List<Point> hullPointList = new ArrayList<Point>();
List<Point> filteredPointList = new ArrayList<Point>();
MatOfPoint hullPointMat = new MatOfPoint();
MatOfInt hull = new MatOfInt();
Mat hierarchy = new Mat();
// Find contour
Imgproc.findContours(
binary, contours, hierarchy, Imgproc.RETR_TREE, Imgproc.CHAIN_APPROX_SIMPLE);
// Find convex hull
for (int k = 0; k < contours.size(); k++) {
Imgproc.convexHull(contours.get(k), hull);
for (int j = 0; j < hull.toList().size(); j++) {
hullPointList.add(contours.get(k).toList().get(hull.toList().get(j)));
}
hullPointMat.fromList(hullPointList);
hullPoints.add(hullPointMat);
}
// Filter hull points. Only hull points relevant to hull classification
// will remain.
// Also, count the number of filtered hull points in left and right.
for (int l = 0; l < hullPointList.size(); l++) {
if (hullPointList.get(l).y < binary.rows() * 0.25) {
if (l != hullPointList.size() - 1) {
if (Math.hypot(
hullPointList.get(l).x - hullPointList.get(l + 1).x,
hullPointList.get(l).y - hullPointList.get(l + 1).y)
/ binary.cols()
> 0.08) {
filteredPointList.add(hullPointList.get(l));
// Core.circle(rgb,
// new Point(UL.x + hullPointList.get(l).x, UL.y
// + hullPointList.get(l).y), 5,
// new Scalar(0, 255, 0));
}
}
}
}
// Sort points by x axis, increasing
if (filteredPointList.size() > 1) {
if (filteredPointList.get(0).x > filteredPointList.get(1).x) {
Point temp = filteredPointList.get(0);
filteredPointList.set(0, filteredPointList.get(1));
filteredPointList.set(1, temp);
}
if (filteredPointList.get(0).y > filteredPointList.get(1).y) return 1; // R
else return 2; // U
}
return 0;
}
