求助－图片旋转后丢失部分图片

Question

点击旋转（rotate）后的图片被截掉了一部分边角，不知是哪的问题，求高手帮小弟看下import java.awt.event.*;
import java.awt.geom.*;
import java.awt.image.*;
import java.io.*;
import javax.swing.*;
import java.awt.*;
public class ImageProcessingTest {
    public static void main(String[] args) {
        JFrame frame = new ImageProcessingFrame();
//        frame.show();
        frame.setVisible(true);
    }
}
class ImageProcessingFrame extends JFrame implements ActionListener {
    public ImageProcessingFrame() {
        setTitle("ImageProcessingTest");
        setSize(300, 400);
        addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });        Container contentPane = getContentPane();
        panel = new ImageProcessingPanel();
        contentPane.add(panel, "Center");        JMenu fileMenu = new JMenu("File");
        openItem = new JMenuItem("Open");
        openItem.addActionListener(this);
        fileMenu.add(openItem);        exitItem = new JMenuItem("Exit");
        exitItem.addActionListener(this);
        fileMenu.add(exitItem);        JMenu editMenu = new JMenu("Edit");
        blurItem = new JMenuItem("Blur");
        blurItem.addActionListener(this);
        editMenu.add(blurItem);        sharpenItem = new JMenuItem("Sharpen");
        sharpenItem.addActionListener(this);
        editMenu.add(sharpenItem);        brightenItem = new JMenuItem("Brighten");
        brightenItem.addActionListener(this);
        editMenu.add(brightenItem);        edgeDetectItem = new JMenuItem("Edge detect");
        edgeDetectItem.addActionListener(this);
        editMenu.add(edgeDetectItem);        negativeItem = new JMenuItem("Negative");
        negativeItem.addActionListener(this);
        editMenu.add(negativeItem);        rotateItem = new JMenuItem("Rotate");
        rotateItem.addActionListener(this);
        editMenu.add(rotateItem);        JMenuBar menuBar = new JMenuBar();
        menuBar.add(fileMenu);
        menuBar.add(editMenu);
        setJMenuBar(menuBar);
    }    public void actionPerformed(ActionEvent evt) {
        Object source = evt.getSource();
        if (source == openItem) {
            JFileChooser chooser = new JFileChooser();
            chooser.setCurrentDirectory(new File("."));            chooser.setFileFilter(new javax.swing.filechooser.FileFilter() {
                public boolean accept(File f) {
                    String name = f.getName().toLowerCase();
                    return name.endsWith(".gif") || name.endsWith(".jpg") ||
                            name.endsWith(".jpeg") || f.isDirectory();
                }                public String getDescription() {
                    return "Image files";
                }
            });            int r = chooser.showOpenDialog(this);
            if (r == JFileChooser.APPROVE_OPTION) {
                String name = chooser.getSelectedFile().getAbsolutePath();
                panel.loadImage(name);
            }
        } else if (source == exitItem) {
            System.exit(0);
        } else if (source == blurItem) {
            panel.blur();
        } else if (source == sharpenItem) {
            panel.sharpen();
        } else if (source == brightenItem) {
            panel.brighten();
        } else if (source == edgeDetectItem) {
            panel.edgeDetect();
        } else if (source == negativeItem) {
            panel.negative();
        } else if (source == rotateItem) {
            panel.rotate();
        }
    }    private ImageProcessingPanel panel;
    private JMenuItem openItem;
    private JMenuItem exitItem;
    private JMenuItem blurItem;
    private JMenuItem sharpenItem;
    private JMenuItem brightenItem;
    private JMenuItem edgeDetectItem;
    private JMenuItem negativeItem;
    private JMenuItem rotateItem;
}
class ImageProcessingPanel extends JPanel {
    public void paintComponent(Graphics g) {
//        super.paintComponent(g);
//        super.paint(g);
        if (image != null) {
            g.drawImage(image, 0, 0, null);
        }
    }    public void loadImage(String name) {
        Image loadedImage = Toolkit.getDefaultToolkit().getImage(name);
        MediaTracker tracker = new MediaTracker(this);
        tracker.addImage(loadedImage, 0);
        try {
            tracker.waitForID(0);
        } catch (InterruptedException e) {}
        image = new BufferedImage(loadedImage.getWidth(null),
                                  loadedImage.getHeight(null),
                                  BufferedImage.TYPE_INT_RGB);
        Graphics2D g2 = image.createGraphics();
        g2.drawImage(loadedImage, 0, 0, null);        repaint();
    }    private void filter(BufferedImageOp op) {
        BufferedImage filteredImage = new BufferedImage(image.getWidth(),
                image.getHeight(), BufferedImage.TYPE_INT_ARGB);
        op.filter(image, filteredImage);
        image = filteredImage;
        repaint();
    }    private void convolve(float[] elements) {
        Kernel kernel = new Kernel(3, 3, elements);
        ConvolveOp op = new ConvolveOp(kernel);
        filter(op);
    }    public void blur() {
        float weight = 1.0f / 9.0f;
        float[] elements = new float[9];
        for (int i = 0; i < 9; i++) {
            elements[i] = weight;
        }
        convolve(elements);
    }    public void sharpen() {
        float[] elements = {0.0f, -1.0f, 0.0f, -1.0f, 5.f, -1.0f, 0.0f, -1.0f,
                           0.0f};
        convolve(elements);
    }    void edgeDetect() {
        float[] elements = {0.0f, -1.0f, 0.0f, -1.0f, 4.f, -1.0f, 0.0f, -1.0f,
                           0.0f};
        convolve(elements);
    }    public void brighten() {
        float a = 1.5f;
        float b = -20.0f;
        RescaleOp op = new RescaleOp(a, b, null);
        filter(op);
    }    void negative() {
        byte negative[] = new byte[256];
        for (int i = 0; i < 256; i++) {
            negative[i] = (byte) (255 - i);
        }
        ByteLookupTable table = new ByteLookupTable(0, negative);
        LookupOp op = new LookupOp(table, null);
        filter(op);
    }    void rotate() {
        AffineTransform transform = AffineTransform.getRotateInstance(Math.
                toRadians(30), image.getWidth() / 2, image.getHeight() / 2);
        AffineTransformOp op = new AffineTransformOp(transform,
                AffineTransformOp.TYPE_BILINEAR);
        filter(op);
    }    private BufferedImage image;
}

Answer 1

你的程序里filter()方法中设置旋转之后的BufferedImage大小还是原图的大小，那么肯定会被裁掉多余区域呀。
比如一个固定位置的矩形盒子里放了个矩形，你把矩形拿出来以矩形中心为锚点旋转45度，那么位置不变的话还能再放进盒子里吗？解决这个问题你要么重新设置旋转后的BufferedImage大小，要么旋转前先缩小原始BufferedImage。

Answer 2

旋转超出视界了自然就看不见了
先平移(translate)再旋转

Answer 3

按dracularking兄的办法去做，图片是一边平移一边旋转，我是想让图片围绕原点固定旋转