在Java swing中图片的处理

示例代码：

public class MyShowImage extends JFrame {
    // 保存当前操作的像素矩阵
    private int currentPixArray[] = null;
    // 图像的路径
    private String fileString = null;
    // 用于显示图像的标签
    private JLabel imageLabel = null;
    // 加载的图像
    private BufferedImage newImage;
    // 图像的高和宽
    private int h, w;
    // 保存历史操作图像矩阵
    private LinkedList<int[]> imageStack = new LinkedList<int[]>();
    private LinkedList<int[]> tempImageStack = new LinkedList<int[]>();
    public MyShowImage(String title) {
        super(title);
        this.setSize(800, 600);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        // 创建菜单
        JMenuBar jb = new JMenuBar();
        JMenu fileMenu = new JMenu("文件");
        jb.add(fileMenu);
        JMenuItem openImageMenuItem = new JMenuItem("打开图像");
        fileMenu.add(openImageMenuItem);
        openImageMenuItem.addActionListener(new OpenListener());
        JMenuItem exitMenu = new JMenuItem("退出");
        fileMenu.add(exitMenu);
        exitMenu.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                System.exit(0);
            }
        });
        JMenu operateMenu = new JMenu("图像处理");
        jb.add(operateMenu);
        JMenuItem RGBtoGrayMenuItem = new JMenuItem("灰度图像转换");
        operateMenu.add(RGBtoGrayMenuItem);
        RGBtoGrayMenuItem.addActionListener(new RGBtoGrayActionListener());
        JMenuItem balanceMenuItem = new JMenuItem("均衡化");
        operateMenu.add(balanceMenuItem);
        balanceMenuItem.addActionListener(new BalanceActionListener());
        JMenu frontAndBackMenu = new JMenu("历史操作");
        jb.add(frontAndBackMenu);
        JMenuItem backMenuItem = new JMenuItem("后退");
        frontAndBackMenu.add(backMenuItem);
        backMenuItem.addActionListener(new BackActionListener());
        JMenuItem frontMenuItem = new JMenuItem("前进");
        frontAndBackMenu.add(frontMenuItem);
        frontMenuItem.addActionListener(new FrontActionListener());

        this.setJMenuBar(jb);

        imageLabel = new JLabel("");
        JScrollPane pane = new JScrollPane(imageLabel);
        this.add(pane, BorderLayout.CENTER);

        this.setVisible(true);
    }
    private class OpenListener implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            JFileChooser jc = new JFileChooser();
            jc.setFileFilter(new FileFilter() {
                public boolean accept(File f) { // 设定可用的文件的后缀名
                    if (f.getName().endsWith(".jpg") || f.isDirectory()|| f.getName().endsWith(".gif") || f.getName().endsWith(".bmp")) {
                        return true;
                    }
                    return false;
                }

                public String getDescription() {
                    return "图片(*.jpg,*.gif,*bmp)";
                }
            });
            int returnValue = jc.showOpenDialog(null);
            if (returnValue == JFileChooser.APPROVE_OPTION) {
                File selectedFile = jc.getSelectedFile();
                if (selectedFile != null) {
                    fileString = selectedFile.getAbsolutePath();
                    try {
                        newImage = ImageIO.read(new File(fileString));
                        w = newImage.getWidth();
                        h = newImage.getHeight();
                        currentPixArray = getPixArray(newImage, w, h);
                        imageStack.clear();
                        tempImageStack.clear();
                        imageStack.addLast(currentPixArray);
                        imageLabel.setIcon(new ImageIcon(newImage));

                    } catch (IOException ex) {
                        System.out.println(ex);
                    }

                }
            }
            MyShowImage.this.repaint();
            // MyShowImage.this.pack();
        }
    }
    // ////////////////菜单监听器///////////
    private class RGBtoGrayActionListener implements ActionListener {

        public void actionPerformed(ActionEvent e) {
            int[] resultArray = RGBtoGray(currentPixArray);
            imageStack.addLast(resultArray);
            currentPixArray = resultArray;
            showImage(resultArray);
            tempImageStack.clear();
        }

    }
    private class BalanceActionListener implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            int[] resultArray = balance(currentPixArray);
            imageStack.addLast(resultArray);
            currentPixArray = resultArray;
            showImage(resultArray);
            tempImageStack.clear();
        }

    }
    private class BackActionListener implements ActionListener {

        public void actionPerformed(ActionEvent e) {
            if (imageStack.size() <= 1) {
                JOptionPane.showMessageDialog(null, "此幅图片的处理已经没有后退历史操作了", "提示",
                        JOptionPane.INFORMATION_MESSAGE);
            } else {
                tempImageStack.addLast(imageStack.removeLast());
                currentPixArray = imageStack.getLast();
                showImage(currentPixArray);
            }
        }

    }
    private class FrontActionListener implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            if (tempImageStack.size() < 1) {
                JOptionPane.showMessageDialog(null, "此幅图片的处理已经没有前进历史操作了", "提示",
                        JOptionPane.INFORMATION_MESSAGE);
            } else {
                currentPixArray = tempImageStack.removeFirst();
                imageStack.addLast(currentPixArray);
                showImage(currentPixArray);
            }
        }

    }
    // ////////////////获取图像像素矩阵/////////
    private int[] getPixArray(Image im, int w, int h) {
        int[] pix = new int[w * h];
        PixelGrabber pg = null;
        try {
            pg = new PixelGrabber(im, 0, 0, w, h, pix, 0, w);
            if (pg.grabPixels() != true)
                try {
                    throw new java.awt.AWTException("pg error" + pg.status());
                } catch (Exception eq) {
                    eq.printStackTrace();
                }
        } catch (Exception ex) {
            ex.printStackTrace();
        }
        return pix;
    }
    // ////////////////显示图片///////////
    private void showImage(int[] srcPixArray) {
        Image pic = createImage(new MemoryImageSource(w, h, srcPixArray, 0, w));
        ImageIcon ic = new ImageIcon(pic);
        imageLabel.setIcon(ic);
        imageLabel.repaint();
    }
    // ////////////////灰度转换///////////
    private int[] RGBtoGray(int[] ImageSource) {
        int[] grayArray = new int[h * w];
        ColorModel colorModel = ColorModel.getRGBdefault();
        int i, j, k, r, g, b;
        for (i = 0; i < h; i++) {
            for (j = 0; j < w; j++) {
                k = i * w + j;
                r = colorModel.getRed(ImageSource[k]);
                g = colorModel.getGreen(ImageSource[k]);
                b = colorModel.getBlue(ImageSource[k]);
                int gray = (int) (r * 0.3 + g * 0.59 + b * 0.11);
                r = g = b = gray;
                grayArray[i * w + j] = (255 << 24) | (r << 16) | (g << 8) | b;
            }
        }
        return grayArray;
    }
    // ///////////////图像均衡化///////////
    private int[] balance(int[] srcPixArray) {
        int[] histogram = new int[256];
        int[] dinPixArray = new int[w * h];

        for (int i = 0; i < h; i++) {
            for (int j = 0; j < w; j++) {
                int grey = srcPixArray[i * w + j] & 0xff;
                histogram[grey]++;
            }
        }
        double a = (double) 255 / (w * h);
        double[] c = new double[256];
        c[0] = (a * histogram[0]);
        for (int i = 1; i < 256; i++) {
            c[i] = c[i - 1] + (int) (a * histogram[i]);
        }
        for (int i = 0; i < h; i++) {
            for (int j = 0; j < w; j++) {
                int grey = srcPixArray[i * w + j] & 0x0000ff;
                int hist = (int) c[grey];

                dinPixArray[i * w + j] = 255 << 24 | hist << 16 | hist << 8
                        | hist;
            }
        }
        return dinPixArray;
    }
    public static void main(String[] args) {
        new MyShowImage("ShowImage");
    }

}