【转】Java实现图片等比例压缩 和 精度压缩(保留图片大小)

原文链接

https://my.oschina.net/u/242764/blog/2980538

https://blog.csdn.net/Abubu123/article/details/77099950

package com.bonc.ioc.lmp.common.util;
 
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.RenderingHints;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.awt.image.WritableRaster;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
 
import javax.imageio.ImageIO;
 
import org.junit.Test;
 
 
 
/**  
 * 图片工具类,完成图片的截取
 * 所有方法返回值均未boolean型  
 */  
public class ImageHelper {
	  /**  
     * 实现图像的等比缩放  
     * @param source  
     * @param targetW  
     * @param targetH  
     * @return  
     */  
    private static BufferedImage resize(BufferedImage source, int targetW,   
            int targetH) {   
        // targetW,targetH分别表示目标长和宽   
        int type = source.getType();   
        BufferedImage target = null;   
        double sx = (double) targetW / source.getWidth();   
        double sy = (double) targetH / source.getHeight();   
        // 这里想实现在targetW,targetH范围内实现等比缩放。如果不需要等比缩放   
        // 则将下面的if else语句注释即可   
        if (sx < sy) {   
            sx = sy;   
            targetW = (int) (sx * source.getWidth());   
        } else {   
            sy = sx;   
            targetH = (int) (sy * source.getHeight());   
        }   
        if (type == BufferedImage.TYPE_CUSTOM) { // handmade   
            ColorModel cm = source.getColorModel();   
            WritableRaster raster = cm.createCompatibleWritableRaster(targetW,   
                    targetH);   
            boolean alphaPremultiplied = cm.isAlphaPremultiplied();   
            target = new BufferedImage(cm, raster, alphaPremultiplied, null);   
        } else  
            target = new BufferedImage(targetW, targetH, type);   
        Graphics2D g = target.createGraphics();   
        // smoother than exlax:   
        g.setRenderingHint(RenderingHints.KEY_INTERPOLATION,   
                RenderingHints.VALUE_INTERPOLATION_BICUBIC);   
        g.drawRenderedImage(source, AffineTransform.getScaleInstance(sx, sy));   
        g.dispose();   
        return target;   
    }   
 
    /**  
     * 实现图像的等比缩放和缩放后的截取, 处理成功返回true, 否则返回false  
     * @param inFilePath 要截取文件的路径  
     * @param outFilePath 截取后输出的路径  
     * @param width 要截取宽度  
     * @param hight 要截取的高度  
     * @throws Exception  
     */  
    public static boolean compress(String inFilePath, String outFilePath,   
            int width, int hight) {
        boolean ret = false;
        File file = new File(inFilePath);
        File saveFile = new File(outFilePath);
        InputStream in = null;
        try {
            in = new FileInputStream(file);
            ret = compress(in, saveFile, width, hight);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
            ret = false;
        } finally{
            if(null != in){
                try {
                    in.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
 
        return ret;
    } 
 
    /**  
     * 实现图像的等比缩放和缩放后的截取, 处理成功返回true, 否则返回false  
     * @param in 要截取文件流
     * @param outFilePath 截取后输出的路径  
     * @param width 要截取宽度  
     * @param hight 要截取的高度  
     * @throws Exception  
     */  
    public static boolean compress(InputStream in, File saveFile,   
            int width, int hight) {
//     boolean ret = false;
        BufferedImage srcImage = null;
        try {
            srcImage = ImageIO.read(in);
        } catch (IOException e) {
            e.printStackTrace();
            return false;
        }
 
        if (width > 0 || hight > 0) {
            // 原图的大小
            int sw = srcImage.getWidth();
            int sh = srcImage.getHeight();
            // 如果原图像的大小小于要缩放的图像大小,直接将要缩放的图像复制过去
            if (sw > width && sh > hight) {
                srcImage = resize(srcImage, width, hight);
            } else {
                String fileName = saveFile.getName();
                String formatName = fileName.substring(fileName
                        .lastIndexOf('.') + 1);
                try {
                    ImageIO.write(srcImage, formatName, saveFile);
                } catch (IOException e) {
                    e.printStackTrace();
                    return false;
                }
                return true;
            }
        }
        // 缩放后的图像的宽和高
        int w = srcImage.getWidth();
        int h = srcImage.getHeight();
        // 如果缩放后的图像和要求的图像宽度一样,就对缩放的图像的高度进行截取
        if (w == width) {
            // 计算X轴坐标
            int x = 0;
            int y = h / 2 - hight / 2;
            try {
                saveSubImage(srcImage, new Rectangle(x, y, width, hight), saveFile);
            } catch (IOException e) {
                e.printStackTrace();
                return false;
            }
        }
        // 否则如果是缩放后的图像的高度和要求的图像高度一样,就对缩放后的图像的宽度进行截取
        else if (h == hight) {
            // 计算X轴坐标
            int x = w / 2 - width / 2;
            int y = 0;
            try {
                saveSubImage(srcImage, new Rectangle(x, y, width, hight), saveFile);
            } catch (IOException e) {
                e.printStackTrace();
                return false;                
            }
        }
 
        return true;
    }
 
    /**
     * 实现图像的等比缩放和缩放后的截取, 处理成功返回true, 否则返回false
     * @param in 图片输入流
     * @param saveFile 压缩后的图片输出流
     * @param proportion 压缩比
     * @throws Exception
     */
    public static boolean compress(InputStream in, File saveFile, int proportion) {
        if(null == in
                ||null == saveFile
                ||proportion < 1){// 检查参数有效性
            //LoggerUtil.error(ImageHelper.class, "--invalid parameter, do nothing!");
            return false;
        }
 
        BufferedImage srcImage = null;
        try {
            srcImage = ImageIO.read(in);
        } catch (IOException e) {
            e.printStackTrace();
            return false;
        }
        // 原图的大小
        int width = srcImage.getWidth() / proportion;
        int hight = srcImage.getHeight() / proportion;
 
        srcImage = resize(srcImage, width, hight);
 
        // 缩放后的图像的宽和高
        int w = srcImage.getWidth();
        int h = srcImage.getHeight();
        // 如果缩放后的图像和要求的图像宽度一样,就对缩放的图像的高度进行截取
        if (w == width) {
            // 计算X轴坐标
            int x = 0;
            int y = h / 2 - hight / 2;
            try {
                saveSubImage(srcImage, new Rectangle(x, y, width, hight), saveFile);
            } catch (IOException e) {
                e.printStackTrace();
                return false;
            }
        }
        // 否则如果是缩放后的图像的高度和要求的图像高度一样,就对缩放后的图像的宽度进行截取
        else if (h == hight) {
            // 计算X轴坐标
            int x = w / 2 - width / 2;
            int y = 0;
            try {
                saveSubImage(srcImage, new Rectangle(x, y, width, hight), saveFile);
            } catch (IOException e) {
                e.printStackTrace();
                return false;
            }
        }
 
        return true;
    }
 
    /**
     * 实现缩放后的截图
     * @param image 缩放后的图像
     * @param subImageBounds 要截取的子图的范围
     * @param subImageFile 要保存的文件
     * @throws IOException 
     */  
    private static void saveSubImage(BufferedImage image,   
            Rectangle subImageBounds, File subImageFile) throws IOException {   
        if (subImageBounds.x < 0 || subImageBounds.y < 0  
                || subImageBounds.width - subImageBounds.x > image.getWidth()   
                || subImageBounds.height - subImageBounds.y > image.getHeight()) {   
            //LoggerUtil.error(ImageHelper.class, "Bad subimage bounds");   
            return;   
        }   
        BufferedImage subImage = image.getSubimage(subImageBounds.x,subImageBounds.y, subImageBounds.width, subImageBounds.height);   
        String fileName = subImageFile.getName();   
        String formatName = fileName.substring(fileName.lastIndexOf('.') + 1);   
        ImageIO.write(subImage, formatName, subImageFile);
    }   
    
    
   @Test
   public static void main(String[] args) throws Exception {
 
       /**
        * saveSubImage 截图类的使用
        * srcImage 为BufferedImage对象
        * Rectangle    为需要截图的长方形坐标
        * saveFile 需要保存的路径及名称
        * **/
        //需要截图的长方形坐标
        /*Rectangle rect =new Rectangle();
        rect.x=40;
        rect.y=40;
        rect.height=160;
        rect.width=160;
 
        InputStream in = null;
        //需要保存的路径及名称
        File saveFile = new File("d:\\ioc\\files\\aaa2.jpg");
        //需要进行处理的图片的路径
        in = new FileInputStream(new File("d:\\ioc\\files\\aaa.jpg"));
        BufferedImage srcImage = null;
        //将输入的数据转为BufferedImage对象
        srcImage = ImageIO.read(in);
 
        ImageHelper img=new ImageHelper();
        img.saveSubImage(srcImage, rect, saveFile);*/
 
       /**
        * compress 图片缩放类的使用(缩略图)
        * srcImage 为InputStream对象
        * Rectangle    为需要截图的长方形坐标
        * proportion 为压缩比例
        * **/
        InputStream in = null;
        //缩放后需要保存的路径
        File saveFile = new File("d:\\ioc\\files\\aaa2.jpg");
        try {
            //原图片的路径
            in = new FileInputStream(new File("d:\\ioc\\files\\aaa.jpg"));
            if(compress(in, saveFile, 10)){
            	System.out.println("图片压缩十倍!");
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            in.close();
        }
    }
}

  

保留图片大小,压缩图片精度

import javax.imageio.IIOImage;
import javax.imageio.ImageIO;
import javax.imageio.ImageWriteParam;
import javax.imageio.ImageWriter;
import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.io.*;
import java.util.Iterator;

/**
 * @author: Supermap·F
 * @descripition: 图片压缩,保留图片尺寸大小,压缩精度
 * @date: created in 18:46 2020/8/20
 * @modify: Copyright (c) Supermap All Rights Reserved.
 */
public class ImgUtil {
    public static byte[] compressPictureByQality(byte[] imgByte, float qality){

        byte[] imgBytes = null;
        BufferedImage resultImage = null;
        try {
            ByteArrayInputStream byteInput = new ByteArrayInputStream(imgByte);
            BufferedImage image = ImageIO.read(byteInput);

            //如果图片为空,返回null
            if (image == null){
                return null;
            }

            //得到指定的format图片的writer(迭代器)
            Iterator<ImageWriter> iter = ImageIO.getImageWritersByFormatName("jpeg");

            //得到writer
            ImageWriter writer = (ImageWriter) iter.next();

            //得到指定writer的输出参数设置
            ImageWriteParam iwp = writer.getDefaultWriteParam();

            //设置是否可以压缩
            iwp.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);

            //设置压缩质量参数
            iwp.setCompressionQuality(qality);

            iwp.setProgressiveMode(ImageWriteParam.MODE_DISABLED);

            ColorModel colorModel = ColorModel.getRGBdefault();

            //指定压缩式使用的色彩模式
            iwp.setDestinationType(new javax.imageio.ImageTypeSpecifier(colorModel,colorModel.createCompatibleSampleModel(16,16)));

            //开始打包图片,写入byte[]
            //取的内存输出流
            ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
            IIOImage iImage = new IIOImage(image, null, null);


            //ImageWriter 中用来接收writer信息的output要求必须是ImageOutput
            writer.setOutput(ImageIO.createImageOutputStream(byteArrayOutputStream));
            writer.write(null, iImage, iwp);
            imgBytes = byteArrayOutputStream.toByteArray();

            ByteArrayInputStream byteInputs = new ByteArrayInputStream(imgBytes);
            resultImage = ImageIO.read(byteInputs);

        }catch (IOException e){
            System.out.println("错误");
            e.printStackTrace();
        }
        return imgBytes;

    }

    /**
     *  图片压缩
     * @param image 图片
     * @param qality
     * @return
     * @throws IOException
     */
    public static BufferedImage compressPictureByQalityV2(BufferedImage image, float qality) {

        byte[] imgBytes = null;
        BufferedImage resultImage = null;
        try {
//            ByteArrayInputStream byteInput = new ByteArrayInputStream(imgByte);
//            BufferedImage image = ImageIO.read(byteInput);

            //如果图片为空,返回null
            if (image == null){
                return null;
            }

            //得到指定的format图片的writer(迭代器)
            Iterator<ImageWriter> iter = ImageIO.getImageWritersByFormatName("jpeg");

            //得到writer
            ImageWriter writer = (ImageWriter) iter.next();

            //得到指定writer的输出参数设置
            ImageWriteParam iwp = writer.getDefaultWriteParam();

            //设置是否可以压缩
            iwp.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);

            //设置压缩质量参数
            iwp.setCompressionQuality(qality);

            iwp.setProgressiveMode(ImageWriteParam.MODE_DISABLED);

            ColorModel colorModel = ColorModel.getRGBdefault();

            //指定压缩式使用的色彩模式
            iwp.setDestinationType(new javax.imageio.ImageTypeSpecifier(colorModel,colorModel.createCompatibleSampleModel(16,16)));

            //开始打包图片,写入byte[]
            //取的内存输出流
            ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
            IIOImage iImage = new IIOImage(image, null, null);


            //ImageWriter 中用来接收writer信息的output要求必须是ImageOutput
            writer.setOutput(ImageIO.createImageOutputStream(byteArrayOutputStream));
            writer.write(null, iImage, iwp);
            imgBytes = byteArrayOutputStream.toByteArray();

            ByteArrayInputStream byteInputs = new ByteArrayInputStream(imgBytes);
            resultImage = ImageIO.read(byteInputs);

        }catch (IOException e){
            System.out.println("错误");
            e.printStackTrace();
        }
        return resultImage;
    }

}

  

posted @ 2020-08-19 11:09  涂小二  阅读(2883)  评论(0编辑  收藏  举报