public PdfFormField addSignature(
String name, int page, float llx, float lly, float urx, float ury) {
PdfAcroForm acroForm = stamper.getAcroForm();
PdfFormField signature = PdfFormField.createSignature(stamper);
acroForm.setSignatureParams(signature, name, llx, lly, urx, ury);
acroForm.drawSignatureAppearences(signature, llx, lly, urx, ury);
addAnnotation(signature, page);
return signature;
}
