java 图片压缩

1.用户上传图片太大，前端浏览时出现卡顿，故上传后对图片进行压缩

package net.eoutech.uuwifi.ws.commons.utils;

import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGEncodeParam;
import com.sun.image.codec.jpeg.JPEGImageEncoder;

import javax.imageio.IIOImage;
import javax.imageio.ImageIO;
import javax.imageio.ImageWriteParam;
import javax.imageio.ImageWriter;
import javax.swing.*;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.awt.image.ConvolveOp;
import java.awt.image.Kernel;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

public class ImagesFilerUtil {

    /**
     * 缩放图片(压缩图片质量，改变图片尺寸)
     * 若原图宽度小于新宽度，则宽度不变！
     * @param originalFile 原图片路径地址
     * @param resizedFile 压缩后输出路径地址
     * @param maxWidth 最大宽度
     * @param maxHeight 最大高度
     * @param quality 图片质量参数 0.7f 相当于70%质量
     */
    public static void imageResize(File originalFile, File resizedFile,
                                   int maxWidth, int maxHeight, float quality) throws IOException {

        if (quality > 1) {
            throw new IllegalArgumentException(
                    "图片质量需设置在0.1-1范围");
        }

        ImageIcon ii = new ImageIcon(originalFile.getCanonicalPath());
        Image i = ii.getImage();
        Image resizedImage = null;

        int iWidth = i.getWidth(null);
        int iHeight = i.getHeight(null);

        int newWidth = maxWidth;
        if(iWidth < maxWidth){
            newWidth = iWidth;
        }


        if (iWidth >= iHeight) {
            resizedImage = i.getScaledInstance(newWidth, (newWidth * iHeight)
                    / iWidth, Image.SCALE_SMOOTH);
        }



        int newHeight = maxHeight;
        if(iHeight < maxHeight){
            newHeight = iHeight;
        }

        if(resizedImage==null && iHeight >= iWidth){
            resizedImage = i.getScaledInstance((newHeight * iWidth) / iHeight,
                    newHeight, Image.SCALE_SMOOTH);
        }

        //此代码确保加载图像中的所有像素
        Image temp = new ImageIcon(resizedImage).getImage();

        //创建缓冲图像
        BufferedImage bufferedImage = new BufferedImage(temp.getWidth(null),
                temp.getHeight(null), BufferedImage.TYPE_INT_RGB);

        //将图像复制到缓冲图像
        Graphics g = bufferedImage.createGraphics();

        //清除背景并绘制图像。
        g.setColor(Color.white);
        g.fillRect(0, 0, temp.getWidth(null), temp.getHeight(null));
        g.drawImage(temp, 0, 0, null);
        g.dispose();


        float softenFactor = 0.05f;
        float[] softenArray = { 0, softenFactor, 0, softenFactor,
                1 - (softenFactor * 4), softenFactor, 0, softenFactor, 0 };
        Kernel kernel = new Kernel(3, 3, softenArray);
        ConvolveOp cOp = new ConvolveOp(kernel, ConvolveOp.EDGE_NO_OP, null);
        bufferedImage = cOp.filter(bufferedImage, null);

        //将jpeg写入文件
        FileOutputStream out = new FileOutputStream(resizedFile);

        //将图像编码为jpeg数据流
        JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);

        JPEGEncodeParam param = encoder.getDefaultJPEGEncodeParam(bufferedImage);

        param.setQuality(quality, true);

        encoder.setJPEGEncodeParam(param);
        encoder.encode(bufferedImage);
    }


//方法二

    public static boolean compressPic(String srcFilePath, String descFilePath) throws IOException {
        File file = null;
        BufferedImage src = null;
        FileOutputStream out = null;
        ImageWriter imgWrier;
        ImageWriteParam imgWriteParams;

        // 指定写图片的方式为 jpg
        imgWrier = ImageIO.getImageWritersByFormatName("jpg").next();
        imgWriteParams = new javax.imageio.plugins.jpeg.JPEGImageWriteParam(null);
        // 要使用压缩，必须指定压缩方式为MODE_EXPLICIT
        imgWriteParams.setCompressionMode(imgWriteParams.MODE_EXPLICIT);
        // 这里指定压缩的程度，参数qality是取值0~1范围内，
        imgWriteParams.setCompressionQuality((float) 0.5);
        
        imgWriteParams.setProgressiveMode(imgWriteParams.MODE_DISABLED);
        ColorModel colorModel =ImageIO.read(new File(srcFilePath)).getColorModel();// ColorModel.getRGBdefault();
        // 指定压缩时使用的色彩模式
        // imgWriteParams.setDestinationType(new javax.imageio.ImageTypeSpecifier(
//                colorModel, colorModel.createCompatibleSampleModel(16, 16)));
        imgWriteParams.setDestinationType(new javax.imageio.ImageTypeSpecifier(colorModel, colorModel.createCompatibleSampleModel(16, 16)));

        try {
            if (isBlank(srcFilePath)) {
                return false;
            } else {
                file = new File(srcFilePath);System.out.println(file.length());
                src = ImageIO.read(file);
                out = new FileOutputStream(descFilePath);

                imgWrier.reset();
                // 必须先指定 out值，才能调用write方法, ImageOutputStream可以通过任何
                // OutputStream构造
                imgWrier.setOutput(ImageIO.createImageOutputStream(out));
                // 调用write方法，就可以向输入流写图片
                imgWrier.write(null, new IIOImage(src, null, null),
                        imgWriteParams);
                out.flush();
                out.close();
            }
        } catch (Exception e) {
            e.printStackTrace();
            return false;
        }finally {

    try {
        if(out!=null) out.close();
    } catch (Exception e1) {
        e1.printStackTrace();
    }
    }

return true;
    }
    public static boolean isBlank(String string) {
        if (string == null || string.length() == 0 || string.trim().equals("")) {
            return true;
        }
        return false;
    }




}

调用

ImagesFilerUtil.compressPic(path,path);
ImagesFilerUtil.zipImageFile(new File(path),new File(path),500,500,0.5f);

完