java图片缩放

package com.rubekid.springmvc.utils;

import java.awt.AlphaComposite;
import java.awt.Graphics2D;
import java.awt.geom.AffineTransform;
import java.awt.image.AffineTransformOp;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Collection;

import javax.imageio.ImageIO;

import net.sf.jmimemagic.MagicException;
import net.sf.jmimemagic.MagicMatchNotFoundException;
import net.sf.jmimemagic.MagicParseException;

import org.apache.commons.io.FileUtils;
import org.summercool.image.AnimatedGifEncoder;
import org.summercool.image.GifDecoder;
import org.summercool.image.Scalr;
import org.summercool.image.Scalr.Method;
import org.summercool.image.Scalr.Mode;

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

import eu.medsea.mimeutil.MimeUtil; 

/**
 * 图片压缩处理
 * @author Rubekid
 *
 */
public class ImageScale {

    public static final String TYPE_JPEG = "jpg";

    public static final String TYPE_PNG = "png";

    public static final String TYPE_GIF = "gif";

    public static final String TYPE_BMP = "bmp";

    /**
     * 图片缩放
     * @param srcFile
     * @param destFile
     * @param maxWidth
     * @param maxHeight
     * @param type
     * @param quality
     * @throws IOException
     */
    public static void resize(File srcFile, File destFile, int maxWidth, int maxHeight, String type, float quality) throws IOException{
        if(TYPE_GIF.equals(type)){
            resizeGif(srcFile, destFile, maxWidth, maxHeight);
        }
        else if(TYPE_PNG.equals(type)){
            resizePng(srcFile, destFile, maxWidth, maxHeight);
        }
        else{
            resizeJpeg(srcFile, destFile, maxWidth, maxHeight, quality);
        }
    }

    /**
     * 图片缩放
     * @param srcFile
     * @param destFile
     * @param maxWidth
     * @param maxHeight
     * @param type
     * @throws IOException
     */
    public static void resize(File srcFile, File destFile, int maxWidth, int maxHeight, String type) throws IOException{
        resize(srcFile, destFile, maxWidth, maxHeight, type, 0.8f);
    }

    /**
     * 图片缩放
     * @param srcFile
     * @param destFile
     * @param maxWidth
     * @param maxHeight
     * @throws Exception
     */
    public static void resize(File srcFile, File destFile, int maxWidth, int maxHeight, float quality) throws Exception{
        resize(srcFile, destFile, maxWidth, maxHeight, getType(srcFile), quality);
    }

    /**
     * 图片缩放
     * @param srcFile
     * @param destFile
     * @param maxWidth
     * @param maxHeight
     * @throws Exception
     */
    public static void resize(File srcFile, File destFile, int maxWidth, int maxHeight) throws Exception{
        resize(srcFile, destFile, maxWidth, maxHeight, getType(srcFile));
    }

    /**
     * JPEG图片缩放
     * @param srcFile
     * @param destFile
     * @param maxWidth
     * @param maxHeight
     * @throws IOException
     * @throws ImageFormatException
     */
    public static void resizeJpeg(File srcFile, File destFile, int maxWidth, int maxHeight, float quality) throws IOException{
        BufferedImage image = ImageIO.read(srcFile);

        double scale = 0.8f;
        AffineTransform atf = AffineTransform.getTranslateInstance(scale, scale);

        //AffineTransformOp affineTransformOp = new AffineTransformOp(xform, interpolationType)

        double rate = getResizeRate(srcFile, maxWidth, maxHeight);
        int width = (int)(image.getWidth() * rate);
        int height =(int) (image.getHeight() * rate);
        image = Scalr.resize(image, Method.AUTOMATIC, Mode.AUTOMATIC, width, height);
        BufferedImage bufferedImage = new BufferedImage(image.getWidth(), image.getHeight(), BufferedImage.TYPE_INT_RGB);
        Graphics2D g = bufferedImage.createGraphics();
        g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, 1));
        g.fillRect(0, 0, image.getWidth(), image.getHeight());
        g.drawImage(image, 0, 0, null);
        image = bufferedImage;  

        FileOutputStream out = new FileOutputStream(destFile);
        JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
        JPEGEncodeParam param = encoder.getDefaultJPEGEncodeParam(image);
        param.setQuality(quality, false);
        encoder.setJPEGEncodeParam(param);
        encoder.encode(image);
    }

    /**
     * PNG图片缩放
     * @param srcFile
     * @param destFile
     * @param maxWidth
     * @param maxHeight
     * @throws IOException
     */
    public static void resizePng(File srcFile, File destFile, int maxWidth, int maxHeight) throws IOException{
        BufferedImage bufferedImage = ImageIO.read(srcFile);
        double rate = getResizeRate(srcFile, maxWidth, maxHeight);
        if(rate == 1){
            FileUtils.copyFile(srcFile, destFile);
        }
        else{
            int width = (int)(bufferedImage.getWidth() * rate);
            int height =(int) (bufferedImage.getHeight() * rate);
            BufferedImage result  = Scalr.resize(bufferedImage,Method.AUTOMATIC, Mode.AUTOMATIC, width, height);
            ImageIO.write(result, "png", destFile);
        }
    }

    /**
     * GIF图片缩放
     * @param srcFile
     * @param destFile
     * @param maxWidth
     * @param maxHeight
     * @throws IOException
     */
    public static void resizeGif(File srcFile, File destFile, int maxWidth, int maxHeight) throws IOException{
        GifDecoder gd = new GifDecoder();
        int status = gd.read(new FileInputStream(srcFile));
        if (status != GifDecoder.STATUS_OK) {
            return;
        }
        double rate = getResizeRate(srcFile, maxWidth, maxHeight);
        if(rate == 1){
            FileUtils.copyFile(srcFile, destFile);
        }
        else{
            AnimatedGifEncoder ge = new AnimatedGifEncoder();
            ge.start(new FileOutputStream(destFile));
            ge.setRepeat(0);
            for (int i = 0; i < gd.getFrameCount(); i++) {
                BufferedImage frame = gd.getFrame(i);
                int width = frame.getWidth();
                int height = frame.getHeight();
                width = (int) (width * rate);
                height = (int) (height * rate);

                BufferedImage rescaled = Scalr.resize(frame, Mode.FIT_EXACT, width, height);
                int delay = gd.getDelay(i);
                ge.setDelay(delay);
                ge.addFrame(rescaled);
            }
            ge.finish();
        }
    }

    /**
     * 获取缩放比例
     * @param srcFile
     * @param MaxWidth
     * @param MaxHeight
     * @return
     * @throws IOException
     */
    public static double getResizeRate(    File srcFile, int maxWidth, int maxHeight) throws IOException{
        double rate = 1;
        if(maxWidth==0 && maxHeight == 0){
            return rate;
        }
        BufferedImage bImage = ImageIO.read(srcFile);
        int width = bImage.getWidth();
        int height = bImage.getHeight();
        if(maxWidth == 0 && height > maxHeight){
            rate = (double)maxHeight / height;
        }
        else if(maxHeight == 0 && width > maxWidth){
            rate = (double)maxWidth / width;
        }
        else if((width > maxWidth || height > maxHeight) && maxWidth > 0 && maxHeight > 0){
            rate = (double)maxWidth / width > (double)maxHeight / height ?  (double)maxHeight / height : (double)maxWidth / width ;
        }
        if(rate > 1){
            rate = 1;
        }
        return rate;
    }
    /**
     *
     * @param file
     * @return
     * @Exception
     */
    public static String getMimeType(File file) throws Exception{
        MimeUtil.registerMimeDetector("eu.medsea.mimeutil.detector.MagicMimeMimeDetector");
        Collection<?> mimeTypes = MimeUtil.getMimeTypes(file);
        return mimeTypes.toString();
    }

    /**
     * 获取图片类型（后缀）
     * @param file
     * @return
     * @throws MagicException
     * @throws MagicMatchNotFoundException
     * @throws MagicParseException
     */
    public static String getType(File file) throws Exception{
        String mimeType = getMimeType(file);
        return getType(mimeType);
    }

    /**
     * 获取图片类型（后缀）
     * @param mimeType
     * @return
     */
    public static String getType(String mimeType){
        if("image/gif".equals(mimeType)){
            return TYPE_GIF;
        }
        else if("image/png".equals(mimeType) || "image/x-png".equals(mimeType)){
            return TYPE_PNG;
        }
        else if("image/bmp".equals(mimeType) || "image/x-ms-bmp".equals(mimeType)){
            return TYPE_BMP;
        }
        return TYPE_JPEG;
    }
}

<dependency>
        <groupId>com.mortennobel</groupId>
        <artifactId>java-image-scaling</artifactId>
        <version>0.8.5</version>
    </dependency>

    <dependency>
        <groupId>eu.medsea.mimeutil</groupId>
        <artifactId>mime-util</artifactId>
        <version>2.1.3</version>
    </dependency>

    <dependency>
        <groupId>jmimemagic</groupId>
        <artifactId>jmimemagic</artifactId>
        <version>0.1.2</version>
    </dependency>

    <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>simpleimage</artifactId>
        <version>1.2.3</version>
    </dependency>
  </dependencies>