zxing.net条码解码，无需调整大小

Question

I want to decode Multiple QR Code with zxing.net and DecodeMultiple method but by default it return null collection result. When I resize my picture and then decode most of QR code was decoded successfully but one or two small QR Code not decode. Here is my Pictures:

and here is my code:

BarcodeReader reader = new BarcodeReader();
reader.PossibleFormats = new List<BarcodeFormat>();
reader.PossibleFormats.Add(BarcodeFormat.QR_CODE);
reader.AutoRotate = false;
reader.TryHarder = false;
Bitmap input = (Bitmap)Bitmap.FromFile(Application.StartupPath + "\\1.jpg");
Resize_Picture(Application.StartupPath + "\\1.jpg", Application.StartupPath + "\\1_resized.jpg", 800, 0, 100);
var results = reader.DecodeMultiple((Bitmap)Bitmap.FromFile(Application.StartupPath + "\\2.jpg"));

Why this picture required resize?? what is the best size for QR Code. Please guide me to decode without image resize. thanks

After Edit (I add QR Code for test):

I upload my QR Cod you can download from here .

Answer 1

As far as I can see the default binarizer has some trouble with the background color and the anti-aliasing arround the QR codes. You should use the GlobalHistogramBinarizer.

BarcodeReader reader = new BarcodeReader(null,
    bitmap => new BitmapLuminanceSource(bitmap),
    luminance => new GlobalHistogramBinarizer(luminance));