使用 Java 中的 Zxing 读取二维码

Reading QRCode with Zxing in Java

提问by Johnny

Some questions about using Zxing...

关于使用Zxing的一些问题...

I write the following code to read barcode from an image:

我编写了以下代码来从图像中读取条形码：

public class BarCodeDecode 
{
    /**
     * @param args
     */
    public static void main(String[] args) 
    {
        try
        {
            String tmpImgFile = "D:\FormCode128.TIF";

            Map<DecodeHintType,Object> tmpHintsMap = new EnumMap<DecodeHintType, Object>(DecodeHintType.class);
            tmpHintsMap.put(DecodeHintType.TRY_HARDER, Boolean.TRUE);
            tmpHintsMap.put(DecodeHintType.POSSIBLE_FORMATS, EnumSet.allOf(BarcodeFormat.class));
            tmpHintsMap.put(DecodeHintType.PURE_BARCODE, Boolean.FALSE);

            File tmpFile = new File(tmpImgFile);
            String tmpRetString = BarCodeUtil.decode(tmpFile, tmpHintsMap);
            //String tmpRetString = BarCodeUtil.decode(tmpFile, null);
            System.out.println(tmpRetString);
        }
        catch (Exception tmpExpt)
        {
            System.out.println("main: " + "Excpt err! (" + tmpExpt.getMessage() + ")");
        }
        System.out.println("main: " + "Program end.");
    }

}

public class BarCodeUtil 
{
    private static BarcodeFormat DEFAULT_BARCODE_FORMAT = BarcodeFormat.CODE_128;

    /**
      * Decode method used to read image or barcode itself, and recognize the barcode,
      * get the encoded contents and returns it.
      * @param whatFile image that need to be read.
      * @param config configuration used when reading the barcode.
      * @return decoded results from barcode.
      */
     public static String decode(File whatFile, Map<DecodeHintType, Object> whatHints) throws Exception 
     {
         // check the required parameters
         if (whatFile == null || whatFile.getName().trim().isEmpty())
             throw new IllegalArgumentException("File not found, or invalid file name.");
         BufferedImage tmpBfrImage;
         try 
         {
             tmpBfrImage = ImageIO.read(whatFile);
         } 
         catch (IOException tmpIoe) 
         {
             throw new Exception(tmpIoe.getMessage());
         }
         if (tmpBfrImage == null)
             throw new IllegalArgumentException("Could not decode image.");
         LuminanceSource tmpSource = new BufferedImageLuminanceSource(tmpBfrImage);
         BinaryBitmap tmpBitmap = new BinaryBitmap(new HybridBinarizer(tmpSource));
         MultiFormatReader tmpBarcodeReader = new MultiFormatReader();
         Result tmpResult;
         String tmpFinalResult;
         try 
         {
             if (whatHints != null && ! whatHints.isEmpty())
                 tmpResult = tmpBarcodeReader.decode(tmpBitmap, whatHints);
             else
                 tmpResult = tmpBarcodeReader.decode(tmpBitmap);
             // setting results.
             tmpFinalResult = String.valueOf(tmpResult.getText());
         } 
         catch (Exception tmpExcpt) 
         {
             throw new Exception("BarCodeUtil.decode Excpt err - " + tmpExcpt.toString() + " - " + tmpExcpt.getMessage());
         }
         return tmpFinalResult;
    }
}

I try to read the following two images that contains code128 and QRCode.

我尝试阅读以下两个包含 code128 和 QRCode 的图像。

It can work for the code128 but not for the QRCode. Any one knows why...

它适用于 code128 但不适用于 QRCode。有谁知道为什么...

回答by Wr4thon

This Code worked for me.

此代码对我有用。

public static List<string> ScanForBarcodes(string path)
{
  return ScanForBarcodes(new Bitmap(path));
}

public static List<string> ScanForBarcodes(Bitmap bitmap)
{
  // initialize a new Barcode reader.
  BarcodeReader reader = new BarcodeReader
  {
    TryHarder = true, // TryHarder is slower but recognizes more Barcodes
    PossibleFormats = new List<BarcodeFormat> // in the ZXing There is an Enum where all supported barcodeFormats were contained
    {
      BarcodeFormat.CODE_128, 
      BarcodeFormat.QR_CODE,
      //BarcodeFormat. ... ;
    }
  };
  return reader.DecodeMultiple(bitmap).Select(result => result.Text).ToList(); // return only the barcode string.
                                                                               // If you want the full Result use: return reader.DecodeMultiple(bitmap);
}

Did you use this(ZXing.Net) Lib?

你用过这个(ZXing.Net) Lib 吗？

回答by Akshay Taru

Please go through this linkfor complete Tutorial. The author of this code is Joe. I have not developed this code, so I am just doing Copy paste to make sure this is available in case link is broken.

请通过此链接获取完整的教程。这段代码的作者是乔。我还没有开发这个代码，所以我只是在做复制粘贴，以确保在链接断开的情况下它是可用的。

The author is using ZXing(Zebra Crossing Library) you can download it from here, for this tutorial.

作者使用的是ZXing（斑马线库），本教程可以从这里下载。

QR Code Write and Read Program in Java:

Java中的二维码读写程序：

package com.javapapers.java;


import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import javax.imageio.ImageIO;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.BinaryBitmap;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatReader;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.NotFoundException;
import com.google.zxing.Result;
import com.google.zxing.WriterException;
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;

public class QRCode {

  public static void main(String[] args) throws WriterException, IOException,
      NotFoundException {
    String qrCodeData = "Hello World!";
    String filePath = "QRCode.png";
    String charset = "UTF-8"; // or "ISO-8859-1"
    Map<EncodeHintType, ErrorCorrectionLevel> hintMap = new HashMap<EncodeHintType, ErrorCorrectionLevel>();
    hintMap.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.L);

    createQRCode(qrCodeData, filePath, charset, hintMap, 200, 200);
    System.out.println("QR Code image created successfully!");

    System.out.println("Data read from QR Code: "
        + readQRCode(filePath, charset, hintMap));

  }

  public static void createQRCode(String qrCodeData, String filePath,
      String charset, Map hintMap, int qrCodeheight, int qrCodewidth)
      throws WriterException, IOException {
    BitMatrix matrix = new MultiFormatWriter().encode(
        new String(qrCodeData.getBytes(charset), charset),
        BarcodeFormat.QR_CODE, qrCodewidth, qrCodeheight, hintMap);
    MatrixToImageWriter.writeToFile(matrix, filePath.substring(filePath
        .lastIndexOf('.') + 1), new File(filePath));
  }

  public static String readQRCode(String filePath, String charset, Map hintMap)
      throws FileNotFoundException, IOException, NotFoundException {
    BinaryBitmap binaryBitmap = new BinaryBitmap(new HybridBinarizer(
        new BufferedImageLuminanceSource(
            ImageIO.read(new FileInputStream(filePath)))));
    Result qrCodeResult = new MultiFormatReader().decode(binaryBitmap,
        hintMap);
    return qrCodeResult.getText();
  }
}

Maven dependency for the ZXing QR Code library:

ZXing 二维码库的 Maven 依赖项：

<dependency>
  <groupId>com.google.zxing</groupId>
  <artifactId>core</artifactId>
  <version>2.2</version>
</dependency>

<dependency>
  <groupId>com.google.zxing</groupId>
  <artifactId>javase</artifactId>
  <version>2.2</version>
</dependency>

回答by Diego Mariano

Curiously your code works for me, but I had to remove the follow hint.

奇怪的是你的代码对我有用，但我不得不删除跟随提示。

tmpHintsMap.put(DecodeHintType.PURE_BARCODE, Boolean.FALSE);

tmpHintsMap.put(DecodeHintType.PURE_BARCODE, Boolean.FALSE);

When my image is not pure barcode, this hint broke my result.

当我的图像不是纯条形码时，这个提示破坏了我的结果。

Thank you!

谢谢！