求能够缩小图片到一定尺寸的java类

Question

我有一个java程序可以做个这个你试试

Answer 1

package  com.gfc.tool;import java.io.*;
import java.util.*;
import com.sun.image.codec.jpeg.*;
import java.awt.image.*;
import java.awt.*;
import java.net.*;
import java.applet.*;
import java.sql.*;public class Small_pic{
        String InputDir;     //输入图路径
        String OutputDir;    //输出图路径
        String InputFileName;   //输入图文件名
        String OutputFileName;  //输出图文件名
        int OutputWidth=80;      //默认输出图片宽
        int OutputHeight=80;     //默认输出图片高
        int rate=0;
        boolean proportion=true;     //是否等比缩放标记(默认为等比缩放)        public Small_pic(){
              //初始化变量
                InputDir="";
                OutputDir="";
                InputFileName="";
                OutputFileName="";
                OutputWidth=80;
                OutputHeight=80;
                rate=0;
        }        public void setInputDir(String InputDir){
                this.InputDir=InputDir;
        }        public void setOutputDir(String OutputDir){
                this.OutputDir=OutputDir;
        }        public void setInputFileName(String InputFileName){
                this.InputFileName=InputFileName;
        }        public void setOutputFileName(String OutputFileName){
                this.OutputFileName=OutputFileName;
        }        public void setOutputWidth(int OutputWidth){
                this.OutputWidth=OutputWidth;
        }        public void setOutputHeight(int OutputHeight){
                this.OutputHeight=OutputHeight;
        }        public void setW_H(int width,int height){
                this.OutputWidth=width;
                this.OutputHeight=height;
        }        public String s_pic(){
                BufferedImage image;
                String NewFileName;
                //建立输出文件对象
                File file = new File(OutputDir+OutputFileName);
                FileOutputStream tempout =null;
                try{
                        tempout= new FileOutputStream(file);
                }catch(Exception ex){
                        System.out.println(ex.toString());
                }
                Image img=null;
                Toolkit tk=Toolkit.getDefaultToolkit();
                Applet app=new Applet();
                MediaTracker mt = new MediaTracker(app);
                try {
                        img=tk.getImage(InputDir+InputFileName);
                        mt.addImage(img, 0);
                        mt.waitForID(0);
                }catch(Exception e) {
                        e.printStackTrace();
                }                if(img.getWidth(null)==-1){
                        System.out.println("   can't read,retry!"+"<BR>");
                        return "no";
                }else{
                      int new_w;
                      int new_h;
                      if (this.proportion==true)  //判断是否是等比缩放.
                      {
                        //为等比缩放计算输出的图片宽度及高度
                        double rate1=((double)img.getWidth(null))/(double)OutputWidth+0.1;
                        double rate2=((double)img.getHeight(null))/(double)OutputHeight+0.1;
                        double rate=rate1>rate2?rate1:rate2;
                        new_w=(int)(((double)img.getWidth(null))/rate);
                        new_h=(int)(((double)img.getHeight(null))/rate);
                      }
                      else{
                        new_w=OutputWidth;     //输出的图片宽度
                        new_h=OutputHeight;    //输出的图片高度
                      }
                    BufferedImage buffImg = new BufferedImage(new_w,new_h,BufferedImage.TYPE_INT_RGB);                        Graphics g = buffImg.createGraphics();                        g.setColor(Color.white);
                        g.fillRect(0,0,new_w,new_h);                        g.drawImage(img,0,0,new_w,new_h,null);
                        g.dispose();                        JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(tempout);
                        try{
                                encoder.encode(buffImg);
                                tempout.close();
                        }catch(IOException ex){
                                System.out.println(ex.toString());
                        }
                }
                return "ok";
        }        public String s_pic(String InputDir,String OutputDir,String InputFileName,String OutputFileName){
                //输入图路径
                this.InputDir=InputDir;
                 //输出图路径
                this.OutputDir=OutputDir;
                //输入图文件名
                this.InputFileName=InputFileName;
                //输出图文件名
                this.OutputFileName=OutputFileName;
                return s_pic();
        }        public String s_pic(String InputDir,String OutputDir,String InputFileName,String OutputFileName,int width,int height,boolean gp){
                //输入图路径
                this.InputDir=InputDir;
                 //输出图路径
                this.OutputDir=OutputDir;
                  //输入图文件名
                this.InputFileName=InputFileName;
                  //输出图文件名
                this.OutputFileName=OutputFileName;
                 //设置图片长宽
                setW_H(width,height);
                //是否是等比缩放 标记
                this.proportion=gp;
                return s_pic();
        }}