Opencv 自带QRCode和ZBar库识别不出二维码的问题

Question

我想用OPENCV 自带的qrcode识别和ZBar库进行二维码的识别，所用的原图如下（百度上随便找的）：

经过二值化，确定角点和变换矩阵，对原图进行透视变换，再截取图片转换成灰度图得到校正后的二维码图片如下：

分别用自带的QRcode算法和ZBar库对直接二值化的图和经过校正之后的灰度图进行识别，下面用QRcode识别的代码，imageSource是灰度图，thresholdQRcode是直接二值化的图。

QRCodeDetector qrcodeDetector;
    String information1;
    String information2;
    vector<Point> points;
    bool isQRcode1 = qrcodeDetector.detect(imageSource, points);
    if (isQRcode1) {
        information1 = qrcodeDetector.detectAndDecode(imageSource, points);
        cout << "识别成功:"<< information1 << endl;
    }
    else {
        cout << "未识别成功！！" << endl;
    }
    bool isQRcode2 = qrcodeDetector.detect(thresholdQRcode, points);
    if (isQRcode2) {
        information2 = qrcodeDetector.detectAndDecode(thresholdQRcode, points);
        cout << "识别成功:" << information2 << endl;
    }
    else {
        cout << "未识别成功！！" << endl;
    }

接着再用ZBar进行识别，都是一样的代码，代码如下：

//zbar解码--必须在exe同目录下加入两个dll文件,注意灰度图像!!!
    ImageScanner scanner;
    scanner.set_config(ZBAR_NONE, ZBAR_CFG_ENABLE, 1);
    int width1 = imageSource.cols;
    int height1 = imageSource.rows;
    uchar *raw1 = (uchar *)imageSource.data;

    Image imageZbar1(width1, height1, "Y800", raw1, width1*height1);
    scanner.scan(imageZbar1);
    Image::SymbolIterator symbol1 = imageZbar1.symbol_begin();
    if (imageZbar1.symbol_begin() == imageZbar1.symbol_end()) {
        cout << "未识别成功！！" << endl;
    }
    else {
        for (; symbol1 != imageZbar1.symbol_end(); ++symbol1) {
            cout << "类型： " << symbol1->get_type_name() << endl;
            cout << "条码：" << symbol1->get_data() << endl;
        }
    }

    int width2 = thresholdQRcode.cols;
    int height2 = thresholdQRcode.rows;
    uchar *raw2 = (uchar *)thresholdQRcode.data;

    Image imageZbar2(width2, height2, "Y800", raw2, width2*height2);
    scanner.scan(imageZbar2);
    Image::SymbolIterator symbol2 = imageZbar2.symbol_begin();
    if (imageZbar2.symbol_begin() == imageZbar2.symbol_end()) {
        cout << "未识别成功！！" << endl;
    }
    else {
        for (; symbol2 != imageZbar2.symbol_end(); ++symbol2) {
            cout << "类型： " << symbol2->get_type_name() << endl;
            cout << "条码：" << symbol2->get_data() << endl;
        }
    }

实验结果如下：

结果表明QRcode都识别出来了，但是ZBar根据校正后的二维码却没有识别出来。我非常奇怪为啥原来直接二值化的图能够识别，我进行处理校正后的图反而识别不出来了？？希望有人能解释一下。

接下来我不用灰度图，而是直接用矫正后的原图，没有转变成灰度图直接进行识别，结果如下：

出现了新的错误，同样没有识别成功，有没有人说说这错误是什么意思？
然后我对直接二值化的图像进行透视变换截取，得到矫正后的二值化图象来直接进行识别，图像如下：

结果如下：

现在结果完全倒过来了，QRcode对矫正后的图片识别不了，反而ZBar识别成功了，这到底是为啥？或者说有什么更进一步的手段能够提高识别的成功率？

Answer 1

识别的连接：
https://blog.csdn.net/fangyan90617/article/details/80504838
提高准确度的话可以用zxing。

//图片像素按比例缩放
Image imagePic = Image.FromStream(stream);
Bitmap bmp = imagePic as Bitmap;
if (imagePic.Width > 512)
{
int zoomMultiple = imagePic.Width / 512;
int toWidth = 512;
int toHeight = imagePic.Height / zoomMultiple;
bmp = new Bitmap(toWidth, toHeight);
using (Graphics g = Graphics.FromImage(bmp))
{
    g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;
    g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
    g.Clear(Color.Transparent);
    g.DrawImage(imagePic,
                new Rectangle(0, 0, toWidth, toHeight),
                new Rectangle(0, 0, imagePic.Width, imagePic.Height),
                GraphicsUnit.Pixel);
    imagePic.Dispose();
}
//第一种识别方式Zxing
var codes = new BarcodeReader
{
    AutoRotate = true,
    TryInverted = true,
    Options = new DecodingOptions
    {
        TryHarder = true
    }
}.DecodeMultiple(bmp);
if (codes != null)
{
    result.DataView = codes[0].Text;
    result.Code = Enum.ResultCode.DealSuccess;
    result.Message = "识别成功";
    return ReturnResp(result);
}
//第二种识别方式ZBar
using (ZBar.ImageScanner scanner = new ZBar.ImageScanner())
{
    var symbols = scanner.Scan(bmp);
    if (symbols.Count > 0 && symbols[0].Data.Length > 8)
    {
        result.DataView = symbols[0].Data;
        result.Code = Enum.ResultCode.DealSuccess;
        result.Message = "识别成功";
        return ReturnResp(result);
    }
}
//第三种识别方式Zxing
MultiFormatReader reader = new MultiFormatReader();
Dictionary<DecodeHintType, object> dictionary = new Dictionary<DecodeHintType, object> { { DecodeHintType.CHARACTER_SET, "UTF-8" } };
RGBLuminanceSource source = new RGBLuminanceSource(QrCode.Bitmap2Rgb(bmp), bmp.Width, bmp.Height);
BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
Result resultVerify = reader.decode(bitmap, dictionary);
if (resultVerify != null)
{
    result.DataView = resultVerify.Text;
    result.Code = Enum.ResultCode.DealSuccess;
    result.Message = "识别成功";
    return ReturnResp(result);
}
string thoughtWorksResult = "";
//第四种识别方式thoughtWorks
try
{
    QRCodeDecoder decoder = new QRCodeDecoder();
    thoughtWorksResult = decoder.decode(new ThoughtWorks.QRCode.Codec.Data.QRCodeBitmapImage(bmp));
}
catch (Exception)
{
}
if (!string.IsNullOrEmpty(thoughtWorksResult))
{
    result.DataView = thoughtWorksResult;
    result.Code = Enum.ResultCode.DealSuccess;
    result.Message = "识别成功";
    return ReturnResp(result);
}
else
{
    result.Code = Enum.ResultCode.DealFail;
    result.Message = "识别失败";
}