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c#asp.netbarcode-scanner

Error when decoding image


I am trying to use MessagingToolkit to decode an image in C#/ASP.NET. I have managed to encode a qr using this package, but when i try to decode, using the code below it comes up with 2 errors (at the bottom of the page)

I believe this is because I am not getting the image correctly after uploading, but can someone point out exactly where I have gone wrong. Thanks.

    protected void CreateCode_OnClick(object sender, EventArgs e)
    {
        string path = "C:\\Users\\Wayneio\\Documents\\Visual Studio 2012\\Projects\\BAMSystem\\BAMSystem\\";
        if (QRUpload.HasFiles == true)
        {
            FileInfo fi = new FileInfo(QRUpload.FileName);
            string extA = fi.Extension;
            if (extA == ".jpg" || extA == ".png")
            {
               QRCodeDecoder decoder = new QRCodeDecoder();
               QRUpload.SaveAs(path + QRUpload.FileName);

               System.Drawing.Image myImg = System.Drawing.Image.FromFile(path + QRUpload.FileName);
               decoder.Decode(myImg);

            }
            else
            {
                error.Text = "You have uploaded a " + extA + " file. Please upload either a PNG or a JPG";
            }
        }
        else
        {
            error.Text = "You have not uploaded an image.";
        }
    }

Error1:

Error   2   Argument 1: cannot convert from 'System.Drawing.Image' to 'MessagingToolkit.QRCode.Codec.Data.QRCodeImage'  c:\users\wayneio\documents\visual studio 2012\Projects\BAMSystem\BAMSystem\default.aspx.cs  38  35  BAMSystem

Error2:

Error   1   The best overloaded method match for 'MessagingToolkit.QRCode.Codec.QRCodeDecoder.Decode(MessagingToolkit.QRCode.Codec.Data.QRCodeImage)' has some invalid arguments    c:\users\wayneio\documents\visual studio 2012\Projects\BAMSystem\BAMSystem\default.aspx.cs  38  20  BAMSystem

P.S if anyone has documentation on this MessagingToolkit QR package, it would be useful


Solution

  • Decode accepts 'Bitmap' type image.

    System.Drawing.Bitmap myImg = new System.Drawing.Bitmap(FileName);
    Dictionary<DecodeOptions, object> decodingOptions = new Dictionary<DecodeOptions, object>();
    List<BarcodeFormat> possibleFormats = new List<BarcodeFormat>(10);
    
                            possibleFormats.Add(BarcodeFormat.DataMatrix);
                            possibleFormats.Add(BarcodeFormat.QRCode);
                            possibleFormats.Add(BarcodeFormat.PDF417);
                            possibleFormats.Add(BarcodeFormat.Aztec);
                            possibleFormats.Add(BarcodeFormat.UPCE);
                            possibleFormats.Add(BarcodeFormat.UPCA);
                            possibleFormats.Add(BarcodeFormat.Code128);
                            possibleFormats.Add(BarcodeFormat.Code39);
                            possibleFormats.Add(BarcodeFormat.ITF14);
                            possibleFormats.Add(BarcodeFormat.EAN8);
                            possibleFormats.Add(BarcodeFormat.EAN13);
                            possibleFormats.Add(BarcodeFormat.RSS14);
                            possibleFormats.Add(BarcodeFormat.RSSExpanded);
                            possibleFormats.Add(BarcodeFormat.Codabar);
                            possibleFormats.Add(BarcodeFormat.MaxiCode);
    
     decodingOptions.Add(DecodeOptions.TryHarder, true);
     decodingOptions.Add(DecodeOptions.PossibleFormats, possibleFormats);
    Result decodedResult = decoder.Decode(myImg, decodingOptions);
    
              if (decodedResult != null)
                            {
                              //.. success
                            }
    

    Also you can also omit the "decodingOptions" options parameter as decoder also has an overload Decode(Bitmap image).

    System.Drawing.Bitmap myImg = new System.Drawing.Bitmap(FileName);
    Result decodedResult = decoder.Decode(myImg);
    
              if (decodedResult != null)
                            {
                              //.. success
                            }
    

    If you want only QRCode decoding,

        System.Drawing.Bitmap myImg = new System.Drawing.Bitmap(FileName);
        Dictionary<DecodeOptions, object> decodingOptions = new Dictionary<DecodeOptions, object>();
        List<BarcodeFormat> possibleFormats = new List<BarcodeFormat>();
        possibleFormats.Add(BarcodeFormat.QRCode);                              
        decodingOptions.Add(DecodeOptions.TryHarder, true);
        decodingOptions.Add(DecodeOptions.PossibleFormats, possibleFormats);
        Result decodedResult = decoder.Decode(myImg, decodingOptions);
         if (decodedResult != null)
           {
              //.. success
           }
    

    You can find documentation and code here
    http://platform.twit88.com/projects/show/mt-barcode

    Sample code ..download here ..has demo code also
    http://platform.twit88.com/projects/mt-barcode/files

    Code project here
    http://www.codeproject.com/Articles/20574/Open-Source-QRCode-Library