C#でPDFファイルを画像に変換

using PdfiumViewer;
using System;
using System.Drawing.Imaging;
using System.IO;
using System.Linq;

namespace PdfToImage {
  class Program {
    static void Main(string[] args) {
      var projectDirectory = Directory.GetParent(Directory.GetCurrentDirectory()).Parent.FullName;

      try {
        using (var document = PdfDocument.Load(projectDirectory + @"\Samples\document.pdf")) {
          var pageCount = document.PageCount;

          for (int i = 0; i < pageCount; i++) {
            var dpi = 300;

            using (var image = document.Render(i, dpi, dpi, PdfRenderFlags.CorrectFromDpi)) {
              var encoder =
                  ImageCodecInfo.GetImageEncoders().First(c => c.FormatID == ImageFormat.Jpeg.Guid);
              var encoderParams = new EncoderParameters(1);
              encoderParams.Param[0] =
                  new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, 100L);

              image.Save(projectDirectory + @"\Samples\image_" + i + ".jpg", encoder,
                         encoderParams);
            }
          }
        }
      } catch (Exception ex) {
        Console.WriteLine(ex.Message);
      }

      Console.WriteLine("Pdf converted to images. Press any key to exit...");
      Console.ReadKey();
    }
  }
}

using Syncfusion.Pdf.Parsing;
using Syncfusion.Windows.Forms.PdfViewer;
using System.Drawing;
using System.Drawing.Imaging;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace PDFToJPEG {
  class Program {
    static void Main(string[] args) {
      // Initialize the PdfViewer Control
      PdfViewerControl pdfViewer = new PdfViewerControl();

      // Load the input PDF file
      PdfLoadedDocument document = new PdfLoadedDocument("../../Data/document.pdf");

      pdfViewer.Load(document);

      Bitmap image = pdfViewer.ExportAsImage(0);

      // Save the image.
      image.Save("output.jpg", ImageFormat.Jpeg);
    }
  }
}