swt-cctv/src/main/java/io/swtc/SwingCameraWindow.java

package io.swtc;

import com.github.sarxos.webcam.Webcam;
import io.swtc.proccessing.WebcamCaptureLoop;

import javax.swing.*;
import java.awt.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.image.BufferedImage;

public class SwingCameraWindow {
    private final JFrame frame;
    private final CameraPanel cameraPanel;
    private final WebcamCaptureLoop captureLoop;

    public SwingCameraWindow(Webcam webcam) {
        this.frame = new JFrame("scctv@" + webcam.getName());
        this.frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
        this.frame.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                // clean shit up
                frame.dispose();
            }
        });

        this.cameraPanel = new CameraPanel();
        this.frame.add(cameraPanel);
        this.frame.pack();
        this.frame.setSize(640, 480);

        this.captureLoop = new WebcamCaptureLoop(webcam, (BufferedImage img) -> {
            SwingUtilities.invokeLater(() -> {
                cameraPanel.setImage(img);
            });
        });

        this.frame.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                captureLoop.stop();
            }
        });
    }

    public void open() {
        frame.setVisible(true);
        captureLoop.start();
    }

    private static class CameraPanel extends JPanel {
        private BufferedImage currentImage;

        public void setImage(BufferedImage img) {
            this.currentImage = img;
            this.repaint(); // Triggers paintComponent
        }

        @Override
        protected void paintComponent(Graphics g) {
            super.paintComponent(g);
            if (currentImage != null) {
                // Draw the image scaled to the panel size
                g.drawImage(currentImage, 0, 0, getWidth(), getHeight(), null);
            }
        }
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(() -> {
            // init in edt
            Webcam webcam = Webcam.getDefault();
            if (webcam != null) {
                SwingCameraWindow window = new SwingCameraWindow(webcam);
                window.open();
            } else {
                System.err.println("No webcam found!");
            }
        });
    }
}