实现水平方向重采样的java图像处理程序

该程序主要实现水平方向上的灰度图像重采样。重采样通过3个for循环控制完成。原始lena图如下所示：



水平方向每8个点采集一个点的lena图像如下所示：

package p01;

import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.*;

public class chongcaiyang extends Frame{
	Image im, tmp;
	int iw, ih;
	int[] pixels;
	boolean flag_load = false;
	//构造方法
	public chongcaiyang(){
		super("chongcaiyang");
		Panel pdown;
    	Button load, run, save, quit; 
    	addWindowListener(new WindowAdapter(){
    		public void windowClosing(WindowEvent e){
    			System.exit(0);
    		}
    	});
    	
    	pdown = new Panel();
    	pdown.setBackground(Color.lightGray);
    	//定义按钮
    	load = new Button("装载图像");    
    	run = new Button("重采样");
    	save = new Button("保存");
    	quit = new Button("退出");
    	
    	this.add(pdown, BorderLayout.SOUTH);
    	//添加按钮 此处的顺序为案板上的左->右的顺序
    	pdown.add(load);    
    	pdown.add(run);
    	pdown.add(save);
    	pdown.add(quit);
        //按钮的动作程序  装载图像
    	load.addActionListener(new ActionListener(){    
    		public void actionPerformed(ActionEvent e){
    			try {
					jLoad_ActionPerformed(e);
				} catch (IOException e1) {	
					e1.printStackTrace();
				}
    		}
    	});
    	//按钮的动作程序  重采样
    	run.addActionListener(new ActionListener(){    
    		public void actionPerformed(ActionEvent e){
    			try {
					jRun_ActionPerformed(e);
				} catch (IOException e1) {
					// TODO Auto-generated catch block
					e1.printStackTrace();
				}
    		}
    	});
    	//按钮的动作程序 保存
    	save.addActionListener(new ActionListener(){    
    		public void actionPerformed(ActionEvent e){
    			try {
					jSave_ActionPerformed(e);
				} catch (IOException e1) {
					e1.printStackTrace();
				}
    		}
    	});
    	//按钮的动作程序  退出
    	quit.addActionListener(new ActionListener(){    
    		public void actionPerformed(ActionEvent e){
    			jQuit_ActionPerformed(e);
    		}
    	});
	}
	//按钮动作的实现  加载图像
    public void jLoad_ActionPerformed(ActionEvent e) throws IOException{    
    	File inputFile = new File("E:\\f2\\sc\\lena_grey.jpg");
        BufferedImage input = ImageIO.read(inputFile);
		tmp = input;
        flag_load = true;
        repaint();
	}
  //按钮动作的实现  重采样
  	public void jRun_ActionPerformed(ActionEvent e) throws IOException{    
  		if(flag_load){
  			File inputFile = new File("E:\\f2\\sc\\lena_grey.jpg");
  	        BufferedImage input = ImageIO.read(inputFile);
  	        iw = input.getWidth(this);
  	        ih = input.getHeight(this); 
  		//设定N值
  		int N = iw;
  		String s = JOptionPane.showInputDialog(null,"请输入N值(512/256/128/64/32/16/8)");
  		if(s!= null&& !s.equals("")){
  			N = Integer.parseInt(s);
  		}	
  		//检查输入是否正确
  		if((N>512)|(N<8)){
  			N = 512;
  			JOptionPane.showMessageDialog(null, "输入不正确，请重新输入！");
  		}
               //图像重采样
  		BufferedImage grayImage = new BufferedImage(iw, ih, 
					BufferedImage.TYPE_BYTE_GRAY);
  		//kao!三个循环就就能搞定，不就是重采样吗？
		for(int i=0; i<ih-1; i++){
			for(int j=0; j<iw-1; j=j+(ih/N)){
				for(int k=0; k<(ih/N); k++){
					int rgb = input.getRGB(i, j);  
	  				int grey = (int) (0.3*((rgb&0xff0000)>>16)+0.59*((rgb&0xff00)>>8)+0.11*((rgb&0xff)));
	  				rgb = 255<<24|grey<<16|grey<<8|grey;
	  				grayImage.setRGB(i, j+k, rgb);
				}
			}
		}	
                //产生图像
  		tmp = grayImage;
  		flag_load = true;
  		repaint();
  	}else{
  		JOptionPane.showMessageDialog(null, "先点击“装载图像”，3Q！","提示：",
  		        JOptionPane.WARNING_MESSAGE);
  		}
  	}
  //按钮动作的实现保存 
  	public void jSave_ActionPerformed(ActionEvent e) throws IOException{    
        if(flag_load){
        	
    		BufferedImage bi = new BufferedImage(tmp.getWidth(null),tmp.getHeight(null), 
    				BufferedImage.TYPE_INT_RGB);
            Graphics g = bi.getGraphics();
            g.drawImage(tmp,0, 0,null);
            g.dispose();
    		
  		    File save_path=new File("E:\\f2\\sc\\save_t01.jpg");
            ImageIO.write(bi, "JPG", save_path);

  	}else{
  		JOptionPane.showMessageDialog(null, "先点击“装载图像”，3Q！","提示：",
  				JOptionPane.WARNING_MESSAGE);
  		}
  	}
  //按钮动作的实现  退出
  	public void jQuit_ActionPerformed(ActionEvent e){
  		System.exit(0);
  	}
  //绘图函数
  	public void paint(Graphics g){
  		//if(flag_Load){
  			g.drawImage(tmp,50,50,this);
  		//}else{}
  	}
  	
	public static void main(String[] args) {
		chongcaiyang ti = new chongcaiyang();
		ti.setSize(1000,860);
		ti.setVisible(true);
	}
}