package org.multibit.mbm.client.domain.model.qrcode;
import com.google.zxing.BinaryBitmap;
import com.google.zxing.LuminanceSource;
import com.google.zxing.ReaderException;
import com.google.zxing.Result;
import com.google.zxing.client.j2se.BufferedImageLuminanceSource;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.common.HybridBinarizer;
import com.google.zxing.qrcode.QRCodeReader;
import com.google.zxing.qrcode.QRCodeWriter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.awt.image.BufferedImage;
import java.util.Hashtable;
/**
* <p>Utility class to encode and decode QR codes. Used by SwatchGenerator</p>
* <ul>
* <li>Create a QR code from a bitcoin uri</li>
* <li>Decode a QR code to a bitcoin uri</li>
* </p>
*
* @since 0.0.1
*/
public class QRCodeEncoderDecoder {
private static final Logger log = LoggerFactory.getLogger(QRCodeEncoderDecoder.class);
private int width;
private int height;
public QRCodeEncoderDecoder(int width, int height) {
this.width = width;
this.height = height;
}
public BufferedImage encode(String data) {
// get a byte matrix for the data
BitMatrix matrix;
com.google.zxing.Writer writer = new QRCodeWriter();
try {
matrix = writer.encode(data, com.google.zxing.BarcodeFormat.QR_CODE, width, height);
} catch (com.google.zxing.WriterException e) {
// exit the method
return null;
}
// generate an image from the byte matrix
int width = matrix.getWidth();
int height = matrix.getHeight();
// create buffered image to draw to
BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
// iterate through the matrix and draw the pixels to the image
for (int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
boolean imageValue = matrix.get(x, y);
image.setRGB(x, y, (imageValue ? 0 : 0xFFFFFF));
}
}
// //write the image to the output stream
// ImageIO.write(image, "png", outputStream);
return image;
}
public String decode(BufferedImage image) {
// convert the image to a binary bitmap source
LuminanceSource source = new BufferedImageLuminanceSource(image);
BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
// decode the barcode
QRCodeReader reader = new QRCodeReader();
try {
@SuppressWarnings("rawtypes")
Hashtable hints = new Hashtable();
Result result = reader.decode(bitmap, hints);
log.info("Decoded image successfully, result was : '" + result.getText() + "'");
return result.getText();
} catch (ReaderException e) {
// the data is improperly formatted
log.debug(e.getMessage());
log.error("Error while decoding image", e);
}
return "";
}
}