Java QR Code Decoder using ZXing

Today, I came across a requirement in my office project where I had to scan some QR codes in Java. For that we used Tasman Barcode Recognition software owned by Accusoft. Then I was interested to see if there are any free and open source softwares for QR Code encoding/decoding. Then I came across ZXing ("zebra crossing") which is a multi-format 1D/2D barcode/qrcode image processing library implemented in Java, with ports to other languages as well.

Below is the example of how a QR Code image can be decoded using ZXing librabry.

Library Downloads:

You'll need two jars core.jar and javase.jar which can be downloaded from here:

• Core: http://repo1.maven.org/maven2/com/google/zxing/core/
• Javase: http://repo1.maven.org/maven2/com/google/zxing/javase/

Steps:

1. Create a Java Project.

• The following is the project I created in eclipse. 

2. Create a folder "libs" in the above example and put the jars into the folder.

3. Add the jars to the Project Build Path:

• Right click on the project -> Properties -> Java Build Path -> Libraries Tab -> Add JARs...

4. Create a main class as follows:

package com.qrcode.decoder; import java.awt.image.BufferedImage; import java.io.File; import java.io.IOException; import javax.imageio.ImageIO; import com.google.zxing.BinaryBitmap; import com.google.zxing.LuminanceSource; import com.google.zxing.MultiFormatReader; import com.google.zxing.Reader; import com.google.zxing.Result; import com.google.zxing.client.j2se.BufferedImageLuminanceSource; import com.google.zxing.common.HybridBinarizer; public class QRCodeDecoder {        public static void main(String[] args) throws IOException {               File imageFile = new File("D:\\image.png");               BufferedImage image = ImageIO.read(imageFile);               try {                      LuminanceSource source = new BufferedImageLuminanceSource(image);                      BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));                      Reader reader = new MultiFormatReader();                      Result result = reader.decode(bitmap);                      System.out.println("Barcode text: " + result.getText());               } catch (Exception e) {                      e.printStackTrace();               }        } }

5. DONE.

Userful Reference: https://github.com/zxing/zxing/