zxing 无法从图片中找到二维码

Question

扫描如下二维码时：使用

zxing

找不到结果。用我的手机扫描是没有问题的。 我正在使用最新的 Java zwing 3.5.2。

这里是使用的算法（辛苦的工作是由

zxing

完成的）：

    class Results {
        public final double rotation;
        public final List<Result> results;

        Results(double rotation, List<Result> results) {
            this.rotation = rotation;
            this.results = results;
        }
    }

    protected Results getResults(BufferedImage image) {
        LuminanceSource source = new BufferedImageLuminanceSource(image);
        Reader reader = new MultiFormatReader();
        for (int i=0; i<2; ++i) {
            BinaryBitmap bitmap;
            if (i == 0) {
                bitmap = new BinaryBitmap(new GlobalHistogramBinarizer(source));
            } else {
                bitmap = new BinaryBitmap(new HybridBinarizer(source));
            }
            for (int r=0; r<4; ++r) {
                if (r > 0) {
                    bitmap = bitmap.rotateCounterClockwise();
                }

                List<Result> results = tryDetect(reader, bitmap);
                if (results != null) {
                    return new Results(r*90, results);
                }
            }
        }
        return null;
    }

    protected List<Result> tryDetect(Reader reader, BinaryBitmap bitmap) {
        // We should just be catching ReaderException in here but we discovered
        // an ArrayIndexOutOfBoundsException in the zxing library which prevents
        // us from continuing. So we catch everything.

        try {
            // Look for multiple barcodes
            MultipleBarcodeReader multiReader = new GenericMultipleBarcodeReader(reader);
            Result[] theResults = multiReader.decodeMultiple(bitmap, HINTS);
            if (theResults != null) {
                return Arrays.asList(theResults);
            }
        } catch (Exception re) {
        }
        try {
            // Look for multiple barcodes by quadrant
            MultipleBarcodeReader multiReader = new GenericMultipleBarcodeReader(new ByQuadrantReader(reader));
            Result[] theResults = multiReader.decodeMultiple(bitmap, HINTS);
            if (theResults != null) {
                return Arrays.asList(theResults);
            }
        } catch (Exception re) {
        }
        try {
            // Look for pure barcode
            Result theResult = reader.decode(bitmap, HINTS_PURE);
            if (theResult != null) {
                return Arrays.asList(theResult);
            }
        } catch (Exception re) {
        }
        try {
            // Look for normal barcode in photo
            Result theResult = reader.decode(bitmap, HINTS);
            if (theResult != null) {
                return Arrays.asList(theResult);
            }
        } catch (Exception re) {
        }
        return null;
    }
}

我见过的几乎所有

zxing

的用法都非常相似。

我可能是

zwing

或我的代码中的错误。如何克服这个限制？

我尝试通过插值来提高图像的分辨率，但没有成功。

Answer 1

有同样的问题，可以通过在解码之前向 qrCode 图像添加白色边框来解决它

        int borderSize = 50;

        BufferedImage borderedImage = new BufferedImage(
                resizedQrCodeImage.getWidth() + 2 * borderSize,
                resizedQrCodeImage.getHeight() + 2 * borderSize,
                resizedQrCodeImage.getType());

        Graphics2D g2d = borderedImage.createGraphics();
        g2d.setColor(Color.WHITE);
        g2d.fillRect(0, 0, borderedImage.getWidth(), borderedImage.getHeight());
        g2d.drawImage(resizedQrCodeImage, borderSize, borderSize, null);
        g2d.dispose();

然后简单地说：

        try {
            LuminanceSource source = new BufferedImageLuminanceSource(borderedImage);
            BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));

            Result result = new MultiFormatReader().decode(bitmap);
            return Ezvcard.parse(result.getText()).first(); //do not pay attention, simply parsing to the VCard object for my needs
        } catch (NotFoundException e) {
            throw new RuntimeException("Error - qr code can not be decoded.", e);
        }