Convert PDF to images using C# and the Windows Runtime (no third party dependencies).

ConvertToImagesAsync.cs

// csproj:
// <TargetFramework>net8.0-windows10.0.22621.0</TargetFramework>
// <ItemGroup><PackageReference Include="System.Drawing.Common" Version="8.0.6" /></ItemGroup>

using System.Drawing;
using System.Drawing.Imaging;

using Windows.Data.Pdf;
using Windows.Storage;
using Windows.Storage.Streams;

internal class PDF
{
    public static async Task ConvertToImagesAsync(string path)
    {
        var folder = Path.GetFileNameWithoutExtension(path);
        Directory.CreateDirectory(folder);

        var file = await StorageFile.GetFileFromPathAsync(path);
        var doc = await PdfDocument.LoadFromFileAsync(file);

        for (uint i = 0; i < doc.PageCount; i++)
        {
            var page = doc.GetPage(i);
            using var stream = new InMemoryRandomAccessStream();

            await page.RenderToStreamAsync(stream);
            using var image = new Bitmap(stream.AsStream());
            image.Save(Path.Combine(folder, $"{Path.GetFileName(path)}_{i}.png"), ImageFormat.Png);
        }
    }
}