QR Code API needed to detect QR code inside .pdf using C# [closed]

问题

Does anyone know of a QR code API that will help detect a QR barcode inside a .PDF. I would like to break up the .pdf when a QR code is found

回答1:

There are a lot of SDKs / APIs that are able to detect & decode a QR Barcode inside a PDF. You will also have to consider how you will input the PDF and split it.

You did not specify what platform / programming language you are developing in so I will list a few different ones.

If you are looking for an open-source solution for detecting QR Barcodes, then you can use ZXing:

ZXing .NET port to .NET and C#, and related Windows platform

If you are looking for a more complete solution, you can look into using a Commercial (non-free) SDK. Just as a disclaimer, I work for LEADTOOLS and we have a Barcode SDK.

LEADTOOLS also has the ability to load and split a multipage PDF as a part of the Barcode SDK and so you can use 1 SDK to achieve what you want. Here is a small C#.NET method that will split a multipage PDF based on QR barcodes found on each of the pages:

static void SplitPDF(string filename)
{
   BarcodeEngine barcodeEngine = new BarcodeEngine();
   List<int> PageNumbers = new List<int>();
   using (RasterCodecs codecs = new RasterCodecs())
   {
      int totalPages = codecs.GetTotalPages(filename);
      for (int page = 1; page <= totalPages; page++)
         using (RasterImage image = codecs.Load(filename, page))
         {
            BarcodeData barcodeData = barcodeEngine.Reader.ReadBarcode(image, LogicalRectangle.Empty, BarcodeSymbology.QR);
            if (barcodeData != null) // QR Barcode found on this image
               PageNumbers.Add(page);
         }
   }

   int firstPage = 1;
   PDFFile pdfFile = new PDFFile(filename);
   //Loop through and split the PDF according to the barcodes
   for(int i= 0; i < PageNumbers.Count; i++)
   {
      string outputFile = $"{Path.GetDirectoryName(filename)}\\{Path.GetFileNameWithoutExtension(filename)}_{i}.pdf";
      pdfFile.ExtractPages(firstPage, PageNumbers[i] - 1, outputFile);
      firstPage = PageNumbers[i]; //set the first page to the next page
   }
   //split the rest of the PDF based on the last barcode
   if (firstPage != 1)
      pdfFile.ExtractPages(firstPage, -1, $"{Path.GetDirectoryName(filename)}\\{Path.GetFileNameWithoutExtension(filename)}_rest.pdf");
}

回答2:

Use Spire.Pdf and Spire.Barcode from Nuget.

using System;
using System.Collections.Generic;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Text.RegularExpressions;
using System.Web;

using System.Web.UI;
using System.Web.UI.WebControls;
using Spire.Pdf;
using Path = System.IO.Path;

namespace MyTask
{
    public partial class Index : System.Web.UI.Page
    {

        protected void Page_Load(object sender, EventArgs e)
        {
            GetImages(@"C:\Users\prave\Desktop\my.pdf", @"C:\Users\prave\Desktop");
        }

        private static void GetImages(string sourcePdf, string outputPath)
        {
            PdfDocument doc = new PdfDocument();
            doc.LoadFromFile(@"C:\Users\prave\Desktop\my.pdf");

            for (int i = 0; i < doc.Pages.Count; i++)
            {
                PdfPageBase page = doc.Pages[i];

                System.Drawing.Image[] images = page.ExtractImages();
                outputPath = Path.Combine(outputPath, String.Format(@"{0}.jpg", i));
                foreach (System.Drawing.Image image in images)
                {
                    string QRCodeString = GetQRCodeString(image,outputPath);
                    if (QRCodeString == "")
                    {
                        continue;
                    }

                    break;

                }



            }
        }

        private static string GetQRCodeString(System.Drawing.Image img, string outPutPath)
        {

            img.Save(outPutPath, System.Drawing.Imaging.ImageFormat.Jpeg);
            string scaningResult = Spire.Barcode.BarcodeScanner.ScanOne(outPutPath);
            File.Delete(outPutPath);

            return scaningResult;
        }

来源：https://stackoverflow.com/questions/44335923/qr-code-api-needed-to-detect-qr-code-inside-pdf-using-c-sharp

标签

qr-code