问题
I am signing my PDF files programmatically and I would like to add the signature appearance to the PDF : what objects would I need to achieve this ? I know I have to Annotations, BBox and XObject but I don't really know in which order and if I need other things. It is really hard to debug this kind of stuff to find the right configuration so any help would be appreciated !
This is the kind of appearance I want to have :
I am using Zend_Pdf to handle my files.
来源：https://stackoverflow.com/questions/45584622/add-digital-signature-appearance-programmatically