Java实现图片的压缩（包括文件上传的图片压缩）

2016/10/11package com.xj.console.util;import java.awt.Image;import java.awt.image.BufferedImage;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import javax.imageio.ImageIO;//此包是针对文件的上传时引用的包(springMVC)import org.springframework.web.multipart.MultipartFile;//下面这两个包已经被JDK1.7移除，在引用的时候要是报错的话//在Eclipse中将编译器针对过时的类报错的地方改成警告即可//（Preferences/Java/compiler/errors/warning/forbidden-->waring）import com.sun.image.codec.jpeg.JPEGCodec;import com.sun.image.codec.jpeg.JPEGImageEncoder;/** *本类的作用就是将图片文件压缩成指定的宽度和长度 */public class CompressPicDemo(){private File file = null;//文件对象private String inputDir;//输入图路径private String outputDir;//输出图路径private String inputFileName;//输入图文件名private String outputFileName;//输出图文件名private int outputWidth = 100;//输出图片宽度private int outputHeight = 100;//输出图片高度private boolean proportion = true;//输出图片是否等比缩放(默认为true)private MultipartFile myFile;//文件上传MultipartFile对象//初始化变量public CompressPicDemo(){inputDir = "";outputDir = "";inputFileName = "";outputFileName = "";outputWidth = 100;outputHeight = 100;}//属性set方法为对象赋值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 setWidthAndHeight(int width, int height) {this.outputWidth = width;this.outputHeight = height;}public void setMyFile(MultipartFile myFile) {this.myFile = myFile;}//-----------------下面就是调用的方法/** *获得图片大小  *String path:图片路径 */ public long getPicSize(String path){file = new File(path);if(!file.exists){return 0;}else{return file.length();} } /*  *图片处理:不涉及文件上传,简单根据传过来的图片路径和图片名称进行压缩处理  */  public String compressPic(){try{//获得文件源file = new File(inputDir+inputFileName);if(!file.exists()){return "";}//imageIO.read(arg);图片解析,可传入文件,文件输入流等Image img = ImageIO.read(file);if(img.getWidth(null) == -1){return "no";}else{int newWidth;int newHeight;//判断是否等比缩放if(this.proportion == true ){double rate = (double)img.getWidth(null)/(double)outputWidth;newWidth = outputWidth;newHeight = ((double)img.getHeight(null)/rate).intValue();}else{newWidth = outputWidth;newHeight = outputHeght;}/** *Image.SCALE_SMOOTH的缩略算法生成缩略图片的平滑度的优先级比速度高,生成的图片质量好但是速度慢 *根据具体要求取舍时间或是质量 */BufferedImage tag = new BufferedImage((int)newWidth,(int)newHeight,BufferedImage.TYPE_INT_RGB);/* @param    img    the specified image to be drawn.  * @param    x      x坐标. * @param    y      y坐标. * @param    width  the width of the rectangle. * @param    height the height of the rectangle. * @param    observer   像素是否被改变 */tag.getGraphics().drawImage(img,0,0,newWidth,newHeight,null);FileOutputStream out = new FileoutputStream(outputDir+outputFileName);//JPEGImageEncoder可适用于其他图片的类型的转换JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);encoder.encode(tag);out.close;}}    }  /*  *图片处理:涉及文件上传,上传文件获取的是MultipartFile对象,而不是文件路径或是文件名  */  public String compressPicVersion2(){try{if(myFile.empty()){return "";}Image img = ImageIO.read(myFile.getInputStream());if(img.getWidth(null) == -1){return "no";}else{int newWidth;int newHeight;if(this.proportion == true ){double rate = (double)img.getWidth(null)/(double)outputWidth;newWidth = outputWidth;newHeight = ((double)img.getHeight(null)/rate).intValue();}else{newWidth = outputWidth;newHeight = outputHeght;}BufferedImage tag = new BufferedImage((int)newWidth,(int)newHeight,BufferedImage.TYPE_INT_RGB);tag.getGraphics().drawImage(img,0,0,newWidth,newHeight,null);FileOutputStream out = new FileoutputStream(outputDir+outputFileName);JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);encoder.encode(tag);out.close;}}    }  public String compressPic(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setWidthAndHeight(width, height);// 是否是等比缩放 标记this.proportion = gp;return compressPic();}public String compressPicVersion2( MultipartFile myFile , String outputDir, String outputFileName,int width, int height, boolean gp) {this.myFile = myFile;// 输出图路径this.outputDir = outputDir;// 输出图文件名this.outputFileName = outputFileName;// 设置图片长宽setWidthAndHeight(width, height);// 是否是等比缩放 标记this.proportion = gp;return compressPicVersion2();}// main测试// compressPic(大图片路径,生成小图片路径,大图片文件名,生成小图片文名,生成小图片宽度,生成小图片高度,是否等比缩放(默认为true))public static void main(String[] arg) {CompressPicDemo mypic = new CompressPicDemo();int count = 0; // 记录全部图片压缩所用时间for (int i = 0; i < 10; i++) {//压缩十张图片System.out.println("输入的图片大小：" + mypic.getPicSize("e:/temp/"+i+".jpg") / 1024 + "KB");int start = (int) System.currentTimeMillis(); // 开始时间mypic.compressPic("e:/temp/", "e:/tempCopy/", i+".jpg", "r1" + i + ".jpg", 600, 600, true);int end = (int) System.currentTimeMillis(); // 结束时间int re = end - start; // 但图片生成处理时间count += re;System.out.println("第" + (i + 1) + "张图片压缩处理使用了: " + re + "毫秒");System.out.println("输出的图片大小：" + mypic.getPicSize("e:/tempCopy/r1" + i + ".jpg") / 1024 + "KB");}System.out.println("总共用了：" + count + "毫秒");}}