Javaweb 圖片壓縮

 

轉載自 http://blog.csdn.net/mr_smile2014/article/details/51943568

			String yuantu=this.imgFileStore.getRootFile().getPath()+ "/xiangche/" +userid+"/"+newfilename;
			//壓縮後的圖片保存地址
			String yaosuo=this.imgFileStore.getRootFile().getPath()+ "/xiangche/yashuo/" +userid+"/"+newfilename;
			
		    File srcfile = new File(yuantu);  
		    System.out.println("壓縮前srcfile size:" + srcfile.length());  
		    
		    ImageCompress.reduceImg(yuantu,yaosuo, 150,150,null);  
		    File distfile = new File(yaosuo);  
		    System.out.println("壓縮後distfile size:" + distfile.length());  

imageCompress 

package com.hoosee.actions.util;

import java.awt.Image;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;

import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGImageEncoder;
	/**
	 * 圖片壓縮
	 * 
	 * **/
public class ImageCompress {
 
	/** 
     * 採用指定寬度、高度或壓縮比例 的方式對圖片進行壓縮 
     * @param imgsrc 源圖片地址 
     * @param imgdist 目標圖片地址 
     * @param widthdist 壓縮後圖片寬度（當rate==null時，必傳） 
     * @param heightdist 壓縮後圖片高度（當rate==null時，必傳） 
     * @param rate 壓縮比例  
     */  
    public static void reduceImg(String imgsrc, String imgdist, int widthdist,  
            int heightdist, Float rate) {  
        try {  
            File srcfile = new File(imgsrc);  
            // 檢查文件是否存在  
            if (!srcfile.exists()) {  
                return;  
            }  
            // 如果rate不爲空說明是按比例壓縮  
            if (rate != null && rate > 0) {  
                // 獲取文件高度和寬度  
                int[] results = getImgWidth(srcfile);  
                if (results == null || results[0] == 0 || results[1] == 0) {  
                    return;  
                } else {  
                    widthdist = (int) (results[0] * rate);  
                    heightdist = (int) (results[1] * rate);  
                }  
            }  
            // 開始讀取文件並進行壓縮  
            Image src = javax.imageio.ImageIO.read(srcfile);  
            BufferedImage tag = new BufferedImage((int) widthdist,  
                    (int) heightdist, BufferedImage.TYPE_INT_RGB);  
  
            tag.getGraphics().drawImage(  
                    src.getScaledInstance(widthdist, heightdist,  
                            Image.SCALE_SMOOTH), 0, 0, null);  
  
            FileOutputStream out = new FileOutputStream(imgdist);  
            JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);  
            encoder.encode(tag);  
            out.close();  
  
        } catch (IOException ex) {  
            ex.printStackTrace();  
        }  
    }  
    
    /** 
     * 獲取圖片寬度 
     *  
     * @param file 
     *            圖片文件 
     * @return 寬度 
     */  
    public static int[] getImgWidth(File file) {  
        InputStream is = null;  
        BufferedImage src = null;  
        int result[] = { 0, 0 };  
        try {  
            is = new FileInputStream(file);  
            src = javax.imageio.ImageIO.read(is);  
            result[0] = src.getWidth(null); // 得到源圖寬  
            result[1] = src.getHeight(null); // 得到源圖高  
            is.close();  
        } catch (Exception e) {  
            e.printStackTrace();  
        }  
        return result;  
    } 
}