+import java.awt.BorderLayout;
+import java.awt.Container;
+import java.awt.Image;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Random;
+
+import javax.swing.BoxLayout;
+import javax.swing.ImageIcon;
+import javax.swing.JFrame;
+import javax.swing.JLabel;
+import javax.swing.JPanel;
+import javax.swing.JSlider;
+import javax.swing.event.ChangeEvent;
+import javax.swing.event.ChangeListener;
+
+import org.opencv.core.Core;
+import org.opencv.core.CvType;
+import org.opencv.core.Mat;
+import org.opencv.core.MatOfPoint;
+import org.opencv.core.MatOfPoint2f;
+import org.opencv.core.Point;
+import org.opencv.core.Rect;
+import org.opencv.core.Scalar;
+import org.opencv.core.Size;
+import org.opencv.highgui.HighGui;
+import org.opencv.imgcodecs.Imgcodecs;
+import org.opencv.imgproc.Imgproc;
+
+class GeneralContours1 {
+ private Mat srcGray = new Mat();
+ private JFrame frame;
+ private JLabel imgSrcLabel;
+ private JLabel imgContoursLabel;
+ private static final int MAX_THRESHOLD = 255;
+ private int threshold = 100;
+ private Random rng = new Random(12345);
+
+ public GeneralContours1(String[] args) {
+ //! [setup]
+ /// Load source image
+ String filename = args.length > 0 ? args[0] : "../data/stuff.jpg";
+ Mat src = Imgcodecs.imread(filename);
+ if (src.empty()) {
+ System.err.println("Cannot read image: " + filename);
+ System.exit(0);
+ }
+
+ /// Convert image to gray and blur it
+ Imgproc.cvtColor(src, srcGray, Imgproc.COLOR_BGR2GRAY);
+ Imgproc.blur(srcGray, srcGray, new Size(3, 3));
+ //! [setup]
+
+ //! [createWindow]
+ // Create and set up the window.
+ frame = new JFrame("Creating Bounding boxes and circles for contours demo");
+ frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+ // Set up the content pane.
+ Image img = HighGui.toBufferedImage(src);
+ addComponentsToPane(frame.getContentPane(), img);
+ //! [createWindow]
+ // Use the content pane's default BorderLayout. No need for
+ // setLayout(new BorderLayout());
+ // Display the window.
+ frame.pack();
+ frame.setVisible(true);
+ update();
+ }
+
+ private void addComponentsToPane(Container pane, Image img) {
+ if (!(pane.getLayout() instanceof BorderLayout)) {
+ pane.add(new JLabel("Container doesn't use BorderLayout!"));
+ return;
+ }
+
+ JPanel sliderPanel = new JPanel();
+ sliderPanel.setLayout(new BoxLayout(sliderPanel, BoxLayout.PAGE_AXIS));
+
+ //! [trackbar]
+ sliderPanel.add(new JLabel("Canny threshold: "));
+ JSlider slider = new JSlider(0, MAX_THRESHOLD, threshold);
+ slider.setMajorTickSpacing(20);
+ slider.setMinorTickSpacing(10);
+ slider.setPaintTicks(true);
+ slider.setPaintLabels(true);
+ slider.addChangeListener(new ChangeListener() {
+ @Override
+ public void stateChanged(ChangeEvent e) {
+ JSlider source = (JSlider) e.getSource();
+ threshold = source.getValue();
+ update();
+ }
+ });
+ //! [trackbar]
+ sliderPanel.add(slider);
+ pane.add(sliderPanel, BorderLayout.PAGE_START);
+
+ JPanel imgPanel = new JPanel();
+ imgSrcLabel = new JLabel(new ImageIcon(img));
+ imgPanel.add(imgSrcLabel);
+
+ Mat blackImg = Mat.zeros(srcGray.size(), CvType.CV_8U);
+ imgContoursLabel = new JLabel(new ImageIcon(HighGui.toBufferedImage(blackImg)));
+ imgPanel.add(imgContoursLabel);
+
+ pane.add(imgPanel, BorderLayout.CENTER);
+ }
+
+ private void update() {
+ //! [Canny]
+ /// Detect edges using Canny
+ Mat cannyOutput = new Mat();
+ Imgproc.Canny(srcGray, cannyOutput, threshold, threshold * 2);
+ //! [Canny]
+
+ //! [findContours]
+ /// Find contours
+ List<MatOfPoint> contours = new ArrayList<>();
+ Mat hierarchy = new Mat();
+ Imgproc.findContours(cannyOutput, contours, hierarchy, Imgproc.RETR_TREE, Imgproc.CHAIN_APPROX_SIMPLE);
+ //! [findContours]
+
+ //! [allthework]
+ /// Approximate contours to polygons + get bounding rects and circles
+ MatOfPoint2f[] contoursPoly = new MatOfPoint2f[contours.size()];
+ Rect[] boundRect = new Rect[contours.size()];
+ Point[] centers = new Point[contours.size()];
+ float[][] radius = new float[contours.size()][1];
+
+ for (int i = 0; i < contours.size(); i++) {
+ contoursPoly[i] = new MatOfPoint2f();
+ Imgproc.approxPolyDP(new MatOfPoint2f(contours.get(i).toArray()), contoursPoly[i], 3, true);
+ boundRect[i] = Imgproc.boundingRect(new MatOfPoint(contoursPoly[i].toArray()));
+ centers[i] = new Point();
+ Imgproc.minEnclosingCircle(contoursPoly[i], centers[i], radius[i]);
+ }
+ //! [allthework]
+
+ //! [zeroMat]
+ Mat drawing = Mat.zeros(cannyOutput.size(), CvType.CV_8UC3);
+ //! [zeroMat]
+ //! [forContour]
+ /// Draw polygonal contour + bonding rects + circles
+ List<MatOfPoint> contoursPolyList = new ArrayList<>(contoursPoly.length);
+ for (MatOfPoint2f poly : contoursPoly) {
+ contoursPolyList.add(new MatOfPoint(poly.toArray()));
+ }
+
+ for (int i = 0; i < contours.size(); i++) {
+ Scalar color = new Scalar(rng.nextInt(256), rng.nextInt(256), rng.nextInt(256));
+ Imgproc.drawContours(drawing, contoursPolyList, i, color);
+ Imgproc.rectangle(drawing, boundRect[i].tl(), boundRect[i].br(), color, 2);
+ Imgproc.circle(drawing, centers[i], (int) radius[i][0], color, 2);
+ }
+ //! [forContour]
+
+ //! [showDrawings]
+ /// Show in a window
+ imgContoursLabel.setIcon(new ImageIcon(HighGui.toBufferedImage(drawing)));
+ frame.repaint();
+ //! [showDrawings]
+ }
+}
+
+public class GeneralContoursDemo1 {
+ public static void main(String[] args) {
+ // Load the native OpenCV library
+ System.loadLibrary(Core.NATIVE_LIBRARY_NAME);
+
+ // Schedule a job for the event dispatch thread:
+ // creating and showing this application's GUI.
+ javax.swing.SwingUtilities.invokeLater(new Runnable() {
+ @Override
+ public void run() {
+ new GeneralContours1(args);
+ }
+ });
+ }
+}
projects / platform / upstream / opencv.git / commitdiff