This older post is either pointing to mostly dead software or the answers are not fully applicable.
I want to take a PDF document, stick in an image of my signature and have this be digitally signed using a certificate so that the document is secured and any changes will be picked up.
I'd like to open a document, navigate to the relevant signature page, click on the line or draw a box, enter a password and my signature should be drawn and certificate used to digitally sign the doc.
I've tried the following options and here are the problems:
Libre Office: Difficult to sign existing PDF's, better to create pdf's with. Have to add signature image separately.
PortableSigner: Hard to position signature but does the job
Master PDF Editor: Works well but takes 70 dollars to prevent ugly watermark being added to PDF's
Foxit Reader: Only adds image without any certificate signing.