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Aspose.Pdf.Facades.PdfExtractor cannot extract barcode to image

I’m hitting an issue with Aspose.Pdf.Facedes.PdfExtractor ExtractImage() function. There is a QR code in the cover page but this function cannot extract it.

If I try to open the pdf file in MS Word and save as PDF, the function will able to extract the QR Code image.

This issue just happens in a few documents in my project. The code snippet below are what I’m using to extract the QR code:

        private static List<string> ReadQRCodeFromPdfDocument(string filePath)
        {
        try
        {
            Aspose.Pdf.License pdfLicense = new Aspose.Pdf.License();
            pdfLicense.SetLicense("Aspose.Pdf.lic");
        }
        catch
        {
            //ignore case if not found license
        }

        try
        {
            Aspose.BarCode.License barCodeLicense = new Aspose.BarCode.License();
            barCodeLicense.SetLicense("Aspose.Barcode.lic");
        }
        catch
        {
            //ignore case if not found license
        }

        List<string> qrCodetexts = new List<string>();

        Aspose.Pdf.Facades.PdfExtractor pdfExtractor = new Aspose.Pdf.Facades.PdfExtractor();
        pdfExtractor.BindPdf(filePath);

        // Set page range for image extraction
        // Get images in the first page of document
        pdfExtractor.StartPage = 1;
        pdfExtractor.EndPage = 1;

        // Extract the images
        pdfExtractor.ExtractImage();

        // Save images to stream in a loop
        while (pdfExtractor.HasNextImage())
        {
            // Save image to stream
            MemoryStream imgStream = new MemoryStream();
            pdfExtractor.GetNextImage(imgStream);
            imgStream.Position = 0;

            Bitmap bmp;
            //Normal case
            try
            {
                bmp = new Bitmap(imgStream);
            }
            //If convert image error: Parameter is not valid then save image to png for read QR code
            catch
            {
                MemoryStream memoryStream = new MemoryStream(imgStream.GetBuffer());
                memoryStream.Seek(0, SeekOrigin.Begin);
                bmp = new Bitmap(memoryStream);
                bmp.Save(memoryStream, System.Drawing.Imaging.ImageFormat.Png);
            }

            // Recognize the barcode from the image stream above
            using (BarCodeReader reader = new BarCodeReader(bmp, DecodeType.QR))
            {
                reader.RecognitionMode = RecognitionMode.MaxQuality;
                reader.RecognitionMode = RecognitionMode.MaxPerformance;
                while (reader.Read())
                {
                    var qrCodetext = reader.GetCodeText();
                    if (!string.IsNullOrWhiteSpace(qrCodetext) && qrCodetext.IndexOf(_stringPattern) > -1)
                    {
                        qrCodetexts.Add(qrCodetext);
                    }
                }
            }
            if (qrCodetexts.Count > 0) break;
        }

        return qrCodetexts;
    }

Could you guys have any idea what is causing this? and any solution? I will send the source file privately because it contains sensitive data

@toantruong

Please share the sample source file in a private message so that we can test the scenario in our environment and share our feedback with you. You can send it privately by clicking over the username and pressing Blue Message Button.

@toantruong

Thanks for sharing the file in a private message.

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