java使用zxing生成二维码图片和解码,并且压缩生成的二维码图片

二维码生成和解码

需要引入的依赖

<!-- https://mvnrepository.com/artifact/com.google.zxing/javase -->
<dependency>
	<groupId>com.google.zxing</groupId>
	<artifactId>javase</artifactId>
	<version>3.2.1</version>
</dependency>

package com.fchen.qrcode;

import com.google.zxing.*;
import com.google.zxing.client.j2se.BufferedImageLuminanceSource;
import com.google.zxing.client.j2se.MatrixToImageWriter;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.common.HybridBinarizer;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;

import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

public class QRCode {

    /**
     * 生成矩阵
     * @param content
     * @param width
     * @param height
     * @return
     */
    public static BitMatrix generateQRCodeStream(String content,int width,int height){
        Map<EncodeHintType,Object> hints = new HashMap<>();
        hints.put(EncodeHintType.CHARACTER_SET,"UTF-8");    //字符编码
        hints.put(EncodeHintType.MARGIN,0);                 //二维码与图片边距
        hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.Q); //容错等级 L、M、Q、H 其中 L 为最低, H 为最高,等级越高存储信息越少
        BitMatrix bitMatrix;
        try {
            //参数顺序分别为:编码内容,编码类型,生成图片的宽度,生成图片的高度,设置参数
            //高度和宽度都是以像素为单位
            //一般content都是url,扫描后可以自动跳转到指定的地址
            bitMatrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE,width,height,hints);
        } catch (WriterException e) {
            e.printStackTrace();
            return null;
        }
        return bitMatrix;
    }

    public static void generateQRCodeImage(String content, int size){
        try {
            BitMatrix bitMatrix = generateQRCodeStream(content,size,size);
            File file = new File("/home/ttx/app/test.jpg");
            if(!file.getParentFile().exists()){
                file.getParentFile().mkdirs();
            }
            MatrixToImageWriter.writeToFile(bitMatrix,"jpg",file);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }


    public static void decodeImage(String filePath) {
        BufferedImage image;
        try {
            image = ImageIO.read(new File(filePath));
            LuminanceSource source = new BufferedImageLuminanceSource(image);
            Binarizer binarizer = new HybridBinarizer(source);
            BinaryBitmap binaryBitmap = new BinaryBitmap(binarizer);
            Map<DecodeHintType, Object> hints = new HashMap<>();
            hints.put(DecodeHintType.CHARACTER_SET, "UTF-8");
            Result result = new MultiFormatReader().decode(binaryBitmap, hints);// 对图像进行解码
            String content = result.getText();
            System.out.println("图片中内容：  ");
            System.out.println("content： " + content);
        } catch (IOException e) {
            e.printStackTrace();
        } catch (NotFoundException e) {
            e.printStackTrace();
        }
    }

    public static void main(String [] args){
        //generateQRCodeImage("http://www.baidu.com",300);
        decodeImage("C:/home/ttx/app/test.jpg");
    }
}

二维码去白边

//去白边
static BitMatrix deleteWhiteBorder(BitMatrix bitMatrix){
    int [] rec = bitMatrix.getEnclosingRectangle()
    int resWidth = rec[2] + 1
    int resHeight = rec[3] + 1

    BitMatrix resMatrix = new BitMatrix(resWidth,resHeight)
    resMatrix.clear()
    for(int i = 0;i < resWidth; i ++){
        for(int j = 0;j < resHeight;j ++){
            if(bitMatrix.get(i + rec[0], j + rec[1])){
                resMatrix.set(i,j)
            }
        }
    }
    return resMatrix
}

二维码图片压缩

OutputStream os
ImageOutputStream ios
ImageWriter writer
try {
	//createQRCode来自上面的二维码生成
    BitMatrix bitMatrix = createQRCode(data, size, size);
    File file = new File(filePath)
    if(!file.getParentFile().exists()){
        boolean result = file.getParentFile().mkdirs()
        if(!result){
            println("\n\n---------------------------路径创建失败------------------------\n")
            throw new RuntimeException("路径创建失败")
        }else {
            file.setReadable(true,false)
            file.setWritable(true,false)
        }
    }
    //原始图片流
    BufferedImage bufferedImage = MatrixToImageWriter.toBufferedImage(bitMatrix)

    //要压缩的图片流
    // 指定写图片的方式为 pickForm可以是jpg
    Iterator<ImageWriter> writers = ImageIO.getImageWritersByFormatName(picForm)
    if(!writers.hasNext()){
        throw new IllegalStateException("No writers found")
    }
    writer = (ImageWriter)writers.next()

    os = new FileOutputStream(file)
    ios = ImageIO.createImageOutputStream(os)
    writer.reset()
    writer.setOutput(ios)

    ImageWriteParam param = new JPEGImageWriteParam(null)
    // 要使用压缩，必须指定压缩方式为MODE_EXPLICIT
    param.setCompressionMode(ImageWriteParam.MODE_EXPLICIT)
    // 这里指定压缩的程度，参数qality是取值0~1范围内，值越小压缩的越厉害,同时图片的质量越低
    param.setCompressionQuality(compressQuality)
    param.setProgressiveMode(param.MODE_DISABLED)
    // ColorModel.getRGBdefault() 指定压缩时使用的色彩模式
    ColorModel colorModel = bufferedImage.getColorModel()
    param.setDestinationType(new ImageTypeSpecifier(colorModel, colorModel.createCompatibleSampleModel(16, 16)));

    writer.write(null,new IIOImage(bufferedImage,null,null),param)
} catch (Exception e){
    throw e
}finally {
    if(os) {
        os.flush()
        os.close()
    }
    if(ios) {
        ios.flush()
        ios.close()
    }
    if(writer) writer.dispose()
}