寫了有一年多了,還是拿出來,以備後用
package cn.tofishes.util.image;
import java.awt.Image;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import com.sun.image.codec.jpeg.ImageFormatException;
import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGImageEncoder;
/**
* 生成圖片縮略圖
* @author ToFishes
*
*/
public class ReduceImage {
/**
* 自定義寬高生成縮略圖
* @param imgSrc 原圖片的絕對路徑名
* @param imgDist 生成縮略圖後的存放絕對路徑名
* @param widthDist 縮略圖的寬度
* @param heightDist 縮略圖的高度
*/
public static void reduceImg(String imgSrc, String imgDist, int widthDist,
int heightDist) {
try {
File srcfile = new File(imgSrc);
if (!srcfile.exists()) {
return;
}
Image src = javax.imageio.ImageIO.read(srcfile);
reduceImg(src, imgDist, widthDist, heightDist);
} catch (IOException ex) {
ex.printStackTrace();
}
}
/**
* 按照圖片原有比例生成圖片縮略圖,maxSize爲圖片高度、寬度的最大值。
* @param imgSrc 原圖片的絕對路徑
* @param imgDist 生成縮略圖後的存放絕對路徑名
* @param maxSize 圖片高度、寬度的最大值。
*/
public static void reduceImg(String imgSrc, String imgDist, int maxSize) {
File srcfile = new File(imgSrc);
if (!srcfile.exists()) {
return;
}
try {
Image src = javax.imageio.ImageIO.read(srcfile);
float width = src.getWidth(null);
float height = src.getHeight(null);
/* 獲得圖片縮放的比例,哪個大就以哪個爲標準
* 前面的width或height得設置爲float類型,否則相除得整型0
* */
float proportion = width > height ? maxSize/width : maxSize/height;
int widthDist = Math.round(width*proportion);
int heightDist = Math.round(height*proportion);
reduceImg(src, imgDist, widthDist, heightDist);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static void reduceImg(Image src, String imgDist, int widthDist,
int heightDist) throws ImageFormatException, IOException {
if (widthDist <= 0 || heightDist <= 0 ) {
throw new ImageFormatException("縮略圖高寬不能等於小於0");
}
BufferedImage tag = new BufferedImage(widthDist, heightDist,
BufferedImage.TYPE_INT_RGB);
// tag.getGraphics().drawImage(src.getScaledInstance(widthDist,
// heightDist, Image.SCALE_SMOOTH), 0, 0, null);
tag.getGraphics().drawImage(
src.getScaledInstance(widthDist, heightDist,
Image.SCALE_AREA_AVERAGING), 0, 0, null);
FileOutputStream out = new FileOutputStream(imgDist);
JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
encoder.encode(tag);
out.close();
}
/**
* @param args
*/
public static void main(String[] args) {
String imageSrc = "G:/1218794106_ddvip_459.jpg";
String imgDist = "G:/1218794106.jpg";
long start = System.currentTimeMillis();
ReduceImage.reduceImg(imageSrc, imgDist, 120);
long end = System.currentTimeMillis();
System.out.println("耗用時間爲: -- " + (end - start) + "毫秒");
System.out.println("耗用時間爲: -- " + (end - start) / 1000.0 + "秒");
}
}