java - 选择、复制和粘贴图像

Question

我希望我的应用程序执行以下操作:

1 - 选择图像区域并获取坐标。下面的代码应该执行此操作:

import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import javax.swing.*;

public class ScreenCaptureRectangle {

Rectangle captureRect;

ScreenCaptureRectangle(final BufferedImage screen) {
    final BufferedImage screenCopy = new BufferedImage(
            screen.getWidth(),
            screen.getHeight(),
            screen.getType());
    final JLabel screenLabel = new JLabel(new ImageIcon(screenCopy));
    JScrollPane screenScroll = new JScrollPane(screenLabel);

    screenScroll.setPreferredSize(new Dimension(
            (int)(screen.getWidth()/3),
            (int)(screen.getHeight()/3)));

    JPanel panel = new JPanel(new BorderLayout());
    panel.add(screenScroll, BorderLayout.CENTER);

    final JLabel selectionLabel = new JLabel(
            "Drag a rectangle in the screen shot!");
    panel.add(selectionLabel, BorderLayout.SOUTH);

    repaint(screen, screenCopy);
    screenLabel.repaint();

    screenLabel.addMouseMotionListener(new MouseMotionAdapter() {

        Point start = new Point();

        @Override
        public void mouseMoved(MouseEvent me) {
            start = me.getPoint();
            repaint(screen, screenCopy);
            selectionLabel.setText("Start Point: " + start);
            screenLabel.repaint();
        }

        @Override
        public void mouseDragged(MouseEvent me) {
            Point end = me.getPoint();
            captureRect = new Rectangle(start,
                    new Dimension(end.x-start.x, end.y-start.y));
            repaint(screen, screenCopy);
            screenLabel.repaint();
            selectionLabel.setText("Rectangle: " + captureRect);
        }
    });

    JOptionPane.showMessageDialog(null, panel);

    System.out.println("Rectangle of interest: " + captureRect);
}

public void repaint(BufferedImage orig, BufferedImage copy) {
    Graphics2D g = copy.createGraphics();
    g.drawImage(orig,0,0, null);
    if (captureRect!=null) {
        g.setColor(Color.RED);
        g.draw(captureRect);
        g.setColor(new Color(255,255,255,150));
        g.fill(captureRect);
    }
    g.dispose();
}

public static void main(String[] args) throws Exception {
    Robot robot = new Robot();
    final Dimension screenSize = Toolkit.getDefaultToolkit().
            getScreenSize();
    final BufferedImage screen = robot.createScreenCapture(
            new Rectangle(screenSize));

    SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            new ScreenCaptureRectangle(screen);
        }
    });
}
}

2 - 获取坐标并将其用于 getSubimage 方法。

double w  = captureRect.getWidth();
double h  = captureRect.getHeight();
double x  = captureRect.getX();
double y  = captureRect.getY();

int W = (int) w;
int H = (int) h;
int X = (int) x;
int Y = (int) y;

BufferedImage selectImg = screen.getSubimage(x, y, w, h);

3 - 此代码创建一个新的图像文件并复制所选图像。

BufferedImage img = new BufferedImage ( 5000, 5000, BufferedImage.TYPE_INT_RGB );
img.createGraphics().drawImage(selectImg, 0, 0, null);
File final_image = new File("C:/Final.jpg");
ImageIO.write(img, "jpeg", final_image);

应用程序的想法是:
- 选择图像的区域。
- 复制该图像并粘贴到其他文件中。 (当我按下任何按钮时)
- 程序将继续运行，直到我按下另一个按钮。
- 我复制程序的每张图像都会将其粘贴到最后一张图像旁边。

我想我已经接近解决方案了。任何人都可以帮我“连接零件”吗？

Answer 1

首先看一下:

• How to Write a Mouse Listener
• How to Use Buttons, Check Boxes, and Radio Buttons
• How to Write an Action Listeners
• Performing Custom Painting
• Writing/Saving an Image

您需要将已有的概念重新加工成连贯可行的解决方案。也就是说，在您需要的区域之间提供功能(选择区域并保存文件)，以便它们能够干净地协同工作...

以下示例截取屏幕截图，允许您选择一个区域，单击“保存”即可保存文件。该示例检查当前目录中已有多少文件，并将计数加 1，这样就不会覆盖现有文件...

import java.awt.AWTException;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.Robot;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileFilter;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class ScreenImage {

    public static void main(String[] args) {
        new ScreenImage();
    }

    public ScreenImage() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                    ex.printStackTrace();
                }
                try {
                    Robot robot = new Robot();
                    final Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
                    final BufferedImage screen = robot.createScreenCapture(new Rectangle(screenSize));

                    JFrame frame = new JFrame("Testing");
                    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                    frame.add(new TestPane(screen));
                    frame.setSize(400, 400);
                    frame.setLocationRelativeTo(null);
                    frame.setVisible(true);
                } catch (AWTException exp) {
                    exp.printStackTrace();
                }
            }
        });
    }

    public class TestPane extends JPanel {

        private BufferedImage master;

        public TestPane(BufferedImage image) {
            this.master = image;
            setLayout(new BorderLayout());
            final ImagePane imagePane = new ImagePane(image);
            add(new JScrollPane(imagePane));

            JButton btnSave = new JButton("Save");
            add(btnSave, BorderLayout.SOUTH);

            btnSave.addActionListener(new ActionListener() {
                @Override
                public void actionPerformed(ActionEvent e) {
                    try {
                        BufferedImage img = imagePane.getSubImage();
                        master = append(master, img);
                        File save = new File("Capture.png");
                        ImageIO.write(master, "png", save);
                        imagePane.clearSelection();
                        JOptionPane.showMessageDialog(TestPane.this, save.getName() + " was saved", "Saved", JOptionPane.INFORMATION_MESSAGE);
                    } catch (IOException ex) {
                        ex.printStackTrace();
                        JOptionPane.showMessageDialog(TestPane.this, "Failed to save capture", "Error", JOptionPane.ERROR_MESSAGE);
                    }
                }

                public BufferedImage append(BufferedImage master, BufferedImage sub) {

                    // Create a new image which can hold both background and the
                    // new image...
                    BufferedImage newImage = new BufferedImage(
                                    master.getWidth() + sub.getWidth(),
                                    Math.max(master.getHeight(), sub.getHeight()),
                                    BufferedImage.TYPE_INT_ARGB);
                    // Get new image's Graphics context
                    Graphics2D g2d = newImage.createGraphics();
                    // Draw the old background
                    g2d.drawImage(master, 0, 0, null);
                    // Position and paint the new sub image...
                    int y = (newImage.getHeight() - sub.getHeight()) / 2;
                    g2d.drawImage(sub, master.getWidth(), y, null);
                    g2d.dispose();

                    return newImage;

                }

            });

        }

    }

    public class ImagePane extends JPanel {

        private BufferedImage background;
        private Rectangle selection;

        public ImagePane(BufferedImage img) {
            background = img;
            MouseAdapter ma = new MouseAdapter() {

                private Point clickPoint;

                @Override
                public void mousePressed(MouseEvent e) {
                    clickPoint = e.getPoint();
                }

                @Override
                public void mouseDragged(MouseEvent e) {
                    Point dragPoint = e.getPoint();

                    int x = Math.min(clickPoint.x, dragPoint.x);
                    int y = Math.min(clickPoint.y, dragPoint.y);
                    int width = Math.abs(clickPoint.x - dragPoint.x);
                    int height = Math.abs(clickPoint.y - dragPoint.y);

                    selection = new Rectangle(x, y, width, height);
                    repaint();

                }

            };

            addMouseListener(ma);
            addMouseMotionListener(ma);
        }

        public void clearSelection() {
            selection = null;
            repaint();
        }

        public BufferedImage getSubImage() {

            BufferedImage img = null;
            if (selection != null) {

                img = background.getSubimage(selection.x, selection.y, selection.width, selection.height);

            }
            return img;

        }

        @Override
        public Dimension getPreferredSize() {
            return new Dimension(background.getWidth(), background.getHeight());
        }

        @Override
        protected void paintComponent(Graphics g) {
            super.paintComponent(g);
            Graphics2D g2d = (Graphics2D) g.create();
            int x = (getWidth() - background.getWidth()) / 2;
            int y = (getHeight() - background.getHeight()) / 2;
            g2d.drawImage(background, x, y, this);
            if (selection != null) {
                Color stroke = UIManager.getColor("List.selectionBackground");
                Color fill = new Color(stroke.getRed(), stroke.getGreen(), stroke.getBlue(), 128);
                g2d.setColor(fill);
                g2d.fill(selection);
                g2d.setColor(stroke);
                g2d.draw(selection);
            }
            g2d.dispose();
        }

    }

}

因此，除了渲染选择之外，最难的部分是生成结果图像......

基本上，这是通过创建一个新的 BufferedImage 并将旧图像和新的子图像一起绘制来完成的。

public BufferedImage append(BufferedImage master, BufferedImage sub) {

    // Create a new image which can hold both background and the
    // new image...
    BufferedImage newImage = new BufferedImage(
                    master.getWidth() + sub.getWidth(),
                    Math.max(master.getHeight(), sub.getHeight()),
                    BufferedImage.TYPE_INT_ARGB);
    // Get new image's Graphics context
    Graphics2D g2d = newImage.createGraphics();
    // Draw the old background
    g2d.drawImage(master, 0, 0, null);
    // Position and paint the new sub image...
    int y = (newImage.getHeight() - sub.getHeight()) / 2;
    g2d.drawImage(sub, master.getWidth(), y, null);
    g2d.dispose();

    return newImage;

}

该示例将之前的(主)图像替换为此处创建的图像，因此它将不断地将新图像附加到其末尾...