// Called when camera take a frame
@Override
public void onPreviewFrame(byte[] data, Camera camera) {
PlanarYUVLuminanceSource source =
mCameraManager.buildLuminanceSource(data, mPreviewWidth, mPreviewHeight);
HybridBinarizer hybBin = new HybridBinarizer(source);
BinaryBitmap bitmap = new BinaryBitmap(hybBin);
try {
Result result = mQRCodeReader.decode(bitmap);
// Notify We're found a QRCode
if (mOnQRCodeReadListener != null) {
// Transform resultPoints to View coordinates
PointF[] transformedPoints = transformToViewCoordinates(result.getResultPoints());
mOnQRCodeReadListener.onQRCodeRead(result.getText(), transformedPoints);
}
} catch (ChecksumException e) {
Log.d(TAG, "ChecksumException");
e.printStackTrace();
} catch (NotFoundException e) {
// Notify QR not found
if (mOnQRCodeReadListener != null) {
mOnQRCodeReadListener.QRCodeNotFoundOnCamImage();
}
} catch (FormatException e) {
Log.d(TAG, "FormatException");
e.printStackTrace();
} finally {
mQRCodeReader.reset();
}
}
private Result decode(BinaryBitmap bitmap) {
QRCodeReader qrCodeReader = new QRCodeReader();
int[] decodeHintAllowedLength = new int[] {qrCodeW, qrCodeH}; // ???
qrHints.put(DecodeHintType.ALLOWED_LENGTHS, decodeHintAllowedLength);
qrHints.put(DecodeHintType.TRY_HARDER, Boolean.TRUE);
// qrHints.put(DecodeHintType.CHARACTER_SET, );
Result result;
try {
result = qrCodeReader.decode(bitmap, qrHints);
} catch (ReaderException ex) {
throw new RuntimeException("Failed to decode", ex);
}
return result;
}
private void decode(final byte[] data) {
final PlanarYUVLuminanceSource source = cameraManager.buildLuminanceSource(data);
final BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
try {
hints.put(
DecodeHintType.NEED_RESULT_POINT_CALLBACK,
new ResultPointCallback() {
@Override
public void foundPossibleResultPoint(final ResultPoint dot) {
runOnUiThread(
new Runnable() {
@Override
public void run() {
scannerView.addDot(dot);
}
});
}
});
final Result scanResult = reader.decode(bitmap, hints);
final int thumbnailWidth = source.getThumbnailWidth();
final int thumbnailHeight = source.getThumbnailHeight();
final float thumbnailScaleFactor = (float) thumbnailWidth / source.getWidth();
final Bitmap thumbnailImage =
Bitmap.createBitmap(thumbnailWidth, thumbnailHeight, Bitmap.Config.ARGB_8888);
thumbnailImage.setPixels(
source.renderThumbnail(), 0, thumbnailWidth, 0, 0, thumbnailWidth, thumbnailHeight);
runOnUiThread(
new Runnable() {
@Override
public void run() {
handleResult(scanResult, thumbnailImage, thumbnailScaleFactor);
}
});
} catch (final ReaderException x) {
// retry
cameraHandler.post(fetchAndDecodeRunnable);
} finally {
reader.reset();
}
}
private QrDecodingResult decodeQR(BufferedImage image, int filenumber) {
// Create qr image from original for decoding
BufferedImage qrcorner = extractTopRightCornerForQR(image);
BufferedImage blackWhite =
new BufferedImage(
qrcorner.getWidth() / 2, qrcorner.getHeight() / 2, BufferedImage.TYPE_INT_RGB);
Graphics2D g2d = blackWhite.createGraphics();
g2d.drawImage(qrcorner, 0, 0, qrcorner.getWidth() / 2, qrcorner.getHeight() / 2, null);
g2d.dispose();
qrcorner = blackWhite;
QrDecodingResult decodingresult = new QrDecodingResult();
try {
// Decode QR
Result result = null;
Exception decodeException = null;
// Try to decode at least three times
int maxattempts = 3;
int attempt = 1;
while (attempt <= maxattempts) {
logger.debug("Attempt " + attempt);
try {
BinaryBitmap bitmap = getBitmapFromBufferedImage(qrcorner);
result = reader.decode(bitmap);
decodeException = null;
logger.debug("Success!");
break;
} catch (Exception e) {
decodeException = e;
if (debugcorners) {
try {
ImageIO.write(
(RenderedImage) qrcorner,
"jpg",
new File(
tempdir.getAbsolutePath() + "/corner" + filenumber + "_" + attempt + ".jpg"));
} catch (IOException ex) {
ex.printStackTrace();
}
}
}
attempt++;
com.jhlabs.image.MedianFilter filter = new MedianFilter();
BufferedImage newqrcorner =
new BufferedImage(
qrcorner.getWidth(), qrcorner.getHeight(), BufferedImage.TYPE_BYTE_GRAY);
filter.filter(qrcorner, newqrcorner);
qrcorner = newqrcorner;
}
if (decodeException != null) throw decodeException;
// Clean the output from the QR
decodingresult.setOutput(result.getText().replace(" ", "").trim());
// The image filename will be the output
decodingresult.setFilename(decodingresult.getOutput());
// Consistency checking
if (decodingresult.getFilename().length() == 0) {
decodingresult.setFilename("ERROR-EMPTYQR-" + (filenumber + 1));
} else {
String[] parts = decodingresult.getFilename().split("-");
// Now check if the QR string has five parts (which indicates it is an answer sheet)
if (parts.length == 5 && parts[4].trim().contains("BB")) {
decodingresult.setAttemptId(Integer.parseInt(parts[3]));
decodingresult.setAnswersheet(true);
}
// Now check if the QR string has a fourth component (image is rotated)
if (parts.length == 4 && parts[3].trim().contains("R")) {
decodingresult.setRotated(true);
}
// If everything looks well, parse the numbers from the decoded QR info
if (parts.length >= 3) {
// Parse the parts (any exception will be caught as an error)
decodingresult.setUserid(Integer.parseInt(parts[0]));
decodingresult.setCourseid(Integer.parseInt(parts[1]));
decodingresult.setExampage(Integer.parseInt(parts[2]));
// Set filename with the corresponding IDs
decodingresult.setFilename(
decodingresult.getUserid()
+ "-"
+ decodingresult.getCourseid()
+ "-"
+ decodingresult.getExampage());
// Processing was a success
decodingresult.setSuccess(true);
} else {
logger.error("QR contains invalid information");
decodingresult.setFilename("ERROR-INVALIDPARTSQR-" + (filenumber + 1));
}
}
} catch (NotFoundException e) {
decodingresult.setFilename("ERROR-NOTFOUND-" + (filenumber + 1));
} catch (ChecksumException e) {
decodingresult.setFilename("ERROR-CHECKSUM-" + (filenumber + 1));
} catch (FormatException e) {
decodingresult.setFilename("ERROR-CHECKSUM-" + (filenumber + 1));
} catch (Exception e) {
decodingresult.setFilename("ERROR-NULL-" + (filenumber + 1));
}
// Regardless of the result, the back-file name is the sames as the file with a b
decodingresult.setBackfilename(decodingresult.getFilename() + "b");
return decodingresult;
}
