Question

I’ve printed a few short qr-codes (like “HAEB16653”) on a page using this algorythm:

private void CreateQRCodeFile(int size, string filename, string codecontent)
{
  QRCodeWriter writer = new QRCodeWriter();
  com.google.zxing.common.ByteMatrix matrix;
  matrix = writer.encode(codecontent, BarcodeFormat.QR_CODE, size, size, null);
  Bitmap img = new Bitmap(size, size);
  Color Color = Color.FromArgb(0, 0, 0);
  for (int y = 0; y < matrix.Height; ++y)
  {
    for (int x = 0; x < matrix.Width; ++x)
    {
      Color pixelColor = img.GetPixel(x, y);
      //Find the colour of the dot 
      if (matrix.get_Renamed(x, y) == -1)
      {
        img.SetPixel(x, y, Color.White);
      }
      else
      {
        img.SetPixel(x, y, Color.Black);
      }
    }
  }
  img.Save(filename, ImageFormat.Png);
}

The printed barcodes work very well and fast with the integrated WP7 bing scan&search.

When I try to scan the very same printed qrcodes with Stéphanie Hertrichs sample app, scanning is very slow, most do not scan at all, or will only be recognized when I slowly rotate the camera around.

How do I get my scanning to be as reliable as the integrated barcode recognition? I only need to scan QrCodes, so I disabled all the others, still it does not work most of the time.

Is there maybe some other barcode scanning library which is working better?

Answer 1

zxing works very well — just try it on Android. I would not be surprised if it is what powers the Bing search.

The problems are likely in the port. Any non-Java port is at best old and incomplete. I also can’t speak to the efficiency of the approach used in the sample you are looking at. For example, is it really binarizing the image from the APIs correctly? Also make sure it is not using TRY_HARDER mode.