How Add a Dynamically Watermark on a PDF

Question

I need a tool which will dynamically watermark the PDF when the watermark is applied. The dynamically watermark should be defined by me?

Launching the application: A-PDF Watermark
In the main window, clicking "add text watermark" icon, then will open the New Text Watermark configuration window, you can set the Macro value here, the macro is to specify dynamic text, either you can select from the Macro list or input directly
Return to the main window, clicking "File" menu, select "Add PDF Document" item, Add PDF(s) which you want to add watermark
In the watermark list window, marking the text-Macro watermark item as checked
Clicking "Watermark" button to add the pdf watermark