title: Add signature image on PDF without digitally signing it using iTextSharp
body: <p>I am using iTextSharp to work with PDFs. I want to add signature image to Signature field without digitally signing the document (without any involvement of certificate).</p>
  
  <p>Is it possible? I am able to work with digital signing but I also want to just add signature image on signature field without any use of certificates.</p>
  
  <p><strong>UPDATE:</strong></p>
  
  <p>Write now I have following code. </p>
  
  <pre><code>// Set PDF Reader and PDF Stamper
  PdfReader reader = new PdfReader(sourceDocument);
  
  // File stream where PDF will write
  FileStream fout = new FileStream(destinationPath, FileMode.Create, FileAccess.ReadWrite);
  PdfStamper stamper = PdfStamper.CreateSignature(reader, fout, '\0', null, true);
  
  // Set PDF Appearance              
  PdfSignatureAppearance appearance = stamper.SignatureAppearance;
  iTextSharp.text.Image signatureFieldImage = iTextSharp.text.Image.GetInstance(image, System.Drawing.Imaging.ImageFormat.Png);
  appearance.SignatureGraphic = signatureFieldImage;
  appearance.SignatureRenderingMode = PdfSignatureAppearance.RenderingMode.GRAPHIC;
  appearance.SetVisibleSignature(signatureFieldName);
  
  stamper.Close();
  reader.Close();
  fout.Close();
  </code></pre>
  
  <p>But when I try to run it, it gives following error: </p>
  
  <blockquote>
    <p><strong>Signature defined. Must be closed in PdfSignatureAppearance</strong></p>
  </blockquote>