#19 Request: visual aid in signature validity

[Billy A.]

Hi!
I use PDFCreator (http://sourceforge.net/projects/pdfcreator/) to create and sign pdf files and it writes some sort of interactive field in the signature that aids visually in the signature verification, but also shows up differently in different pdf readers. For instance, if I open the pdf with Adobe Reader, there is a yellow question mark with a pink face as a background image and a "Validity unknown" text, if the signature is not validated. If however the signature is validated, instead of the yellow question mark, there is a green tick as background image and a "Signature valid" text. Foxit Reader displays a yellow question mark (without the red face) and a "Signature Not Verified" text. It seems that pdf readers parse differently the fields in this type of signature (perhaps the images used are only from the pdf readers).
It would be very cool if this is implemented in JSignPdf (perhaps as just a checkbox in signature settings).
I have uploaded a signed pdf that I created with PDFCreator (just a blank page). I have used a free digital certificate from Secure Soft, so if you want to validate the signature for testing purposes, you can get their root certificate from http://www.signfiles.com/downloads/ (or I can upload an image showing the results).

[Billy A.]

[Josef Cacek]

The mentioned JSignPdf behavior is related to generated layers in visible signature. The Acrobat 6.0 and higher recommends that only layer n2 and n4 be present.

A new checkbox "Acrobat 6 layer mode" was added to visible signature settings dialog and there you can choose if old mode (all layers) or new mode will be used. The default value of checkbox is checked (i.e. new mode is used).