Преобразование PDF в растровое изображение в C# WPF .NET7

Вы можете использовать библиотеку с открытым исходным кодом Ghostscript вместе с оболочкой Ghostscript.NET.

Вот пример кода:

using System.Drawing;
using Ghostscript.NET;
using Ghostscript.NET.Rasterizer;

namespace PDFTOBitmap
{
    internal class Program
    {
        static void Main()
        { 
            // Input PDF file
            string inputPdfFile = @"C:\input\a.pdf"; 

            // Output BMP file
            string outputBmpFile = @"C:\input\output.bmp"; 

            using (var rasterizer = new GhostscriptRasterizer())
            {
                rasterizer.Open(inputPdfFile);

                // Set the DPI (dots per inch) for rendering
                int dpi = 300; // Adjust the DPI as needed

                // Render the PDF page to a bitmap at the specified DPI
                var bitmap = rasterizer.GetPage(dpi,  1);

                // Save the bitmap to a BMP file
                bitmap.Save(outputBmpFile, System.Drawing.Imaging.ImageFormat.Bmp);
            }
        }
    }
}

Я бы использовал Inkscape с Inkscape.org. Это не относится к WPF, но вы можете экспортировать PDF-файлы в другие типы.

Для экспорта в растровое изображение PNG я использую следующее:

var inkscapePath = @"C:\InkscapeFolder\Inkscape.com";
var processInfo = new ProcessStartInfo(inkscapePath);
var command = $"{PDF-PATH} -z --export-dpi=500 --export-area-drawing --export-png = {EXPORT-PATH}\\{fileName}.png";
processInfo.Arguments = command;
processInfo.CreateNoWindow = true;
processInfo.WindowStyle = ProcessWindowStyle.Hidden;
var cmd = Process.Start(processInfo);

Ниже приведены все варианты:

Available options:
  -V, --version                             Print the Inkscape version number
  -z, --without-gui                         Do not use X server (only process
                                            files from console)
  -g, --with-gui                            Try to use X server (even if
                                            $DISPLAY is not set)
  -f, --file=FILENAME                       Open specified document(s) (option
                                            string may be excluded)
  -p, --print=FILENAME                      Print document(s) to specified
                                            output file (use '| program' for
                                            pipe)
  -e, --export-png=FILENAME                 Export document to a PNG file
  -d, --export-dpi=DPI                      Resolution for exporting to bitmap
                                            and for rasterization of filters
                                            in PS/EPS/PDF (default 90)
  -a, --export-area=x0:y0:x1:y1             Exported area in SVG user units
                                            (default is the page; 0,0 is
                                            lower-left corner)
  -D, --export-area-drawing                 Exported area is the entire
                                            drawing (not page)
  -C, --export-area-page                    Exported area is the entire page
      --export-margin=VALUE                 Only for PS/EPS/PDF, sets margin
                                            in mm around exported area
                                            (default 0)
      --export-area-snap                    Snap the bitmap export area
                                            outwards to the nearest integer
                                            values (in SVG user units)
  -w, --export-width=WIDTH                  The width of exported bitmap in
                                            pixels (overrides export-dpi)
  -h, --export-height=HEIGHT                The height of exported bitmap in
                                            pixels (overrides export-dpi)
  -i, --export-id=ID                        The ID of the object to export
  -j, --export-id-only                      Export just the object with
                                            export-id, hide all others (only
                                            with export-id)
  -t, --export-use-hints                    Use stored filename and DPI hints
                                            when exporting (only with
                                            export-id)
  -b, --export-background=COLOR             Background color of exported
                                            bitmap (any SVG-supported color
                                            string)
  -y, --export-background-opacity=VALUE     Background opacity of exported
                                            bitmap (either 0.0 to 1.0, or 1 to
                                            255)
  -l, --export-plain-svg=FILENAME           Export document to plain SVG file
                                            (no sodipodi or inkscape
                                            namespaces)
  -P, --export-ps=FILENAME                  Export document to a PS file
  -E, --export-eps=FILENAME                 Export document to an EPS file
      --export-ps-level=PS Level            Choose the PostScript Level used
                                            to export. Possible choices are 2
                                            (the default) and 3
  -A, --export-pdf=FILENAME                 Export document to a PDF file
      --export-pdf-version=PDF_VERSION      Export PDF to given version.
                                            (hint: make sure to input the
                                            exact string found in the PDF
                                            export dialog, e.g. "PDF 1.4"
                                            which is PDF-a conformant)
      --export-latex                        Export PDF/PS/EPS without text.
                                            Besides the PDF/PS/EPS, a LaTeX
                                            file is exported, putting the text
                                            on top of the PDF/PS/EPS file.
                                            Include the result in LaTeX like:
                                            \input{latexfile.tex}
  -M, --export-emf=FILENAME                 Export document to an Enhanced
                                            Metafile (EMF) File
  -m, --export-wmf=FILENAME                 Export document to a Windows
                                            Metafile (WMF) File
  -T, --export-text-to-path                 Convert text object to paths on
                                            export (PS, EPS, PDF, SVG)
      --export-ignore-filters               Render filtered objects without
                                            filters, instead of rasterizing
                                            (PS, EPS, PDF)
  -X, --query-x                             Query the X coordinate of the
                                            drawing or, if specified, of the
                                            object with --query-id
  -Y, --query-y                             Query the Y coordinate of the
                                            drawing or, if specified, of the
                                            object with --query-id
  -W, --query-width                         Query the width of the drawing or,
                                            if specified, of the object with
                                            --query-id
  -H, --query-height                        Query the height of the drawing
                                            or, if specified, of the object
                                            with --query-id
  -S, --query-all                           List id,x,y,w,h for all objects
  -I, --query-id=ID                         The ID of the object whose
                                            dimensions are queried
  -x, --extension-directory                 Print out the extension directory
                                            and exit
      --vacuum-defs                         Remove unused definitions from the
                                            defs section(s) of the document
      --verb-list                           List the IDs of all the verbs in
                                            Inkscape
      --verb=VERB-ID                        Verb to call when Inkscape opens.
      --select=OBJECT-ID                    Object ID to select when Inkscape
                                            opens.
      --shell                               Start Inkscape in interactive
                                            shell mode.

Help options:
  -?, --help                                Show this help message
      --usage                               Display brief usage message