PDF .Net

using SautinSoft.Pdf;
var document = PdfDocument.Load(pdfFile);
{
    // Add a signature field.
    var sig = document.Form.Fields.AddSignature(document.Pages[0], 10, 10, 250, 50);
    // Create new Signer.
    PdfSigner pdfSigner = new PdfSigner(@"..\..\..\sautinsoft.pfx", "123456789");
    // Configure signer.
    pdfSigner.Timestamper = new PdfTimestamper(@"https://tsa.cesnet.cz:5817/tsa");
    pdfSigner.SignatureFormat = PdfSignatureFormat.CAdES;
    pdfSigner.SignatureLevel = PdfSignatureLevel.PAdES_B_LTA;
    pdfSigner.HashAlgorithm = PdfHashAlgorithm.SHA256;
    pdfSigner.Location = "Test workplace";
    pdfSigner.Reason = "Test";
    var im = PdfImage.Load(@"..\..\..\JPEG2.jpg");
    sig.Appearance.Icon = im;
    sig.Appearance.TextPlacement = PdfTextPlacement.TextRightOfIcon;
    // Sign PDF Document.
    var si = sig.Sign(pdfSigner);
    // Save PDF Document.
    document.Save();
}