Add watermark to ePub

[Fenicexx]

Hi,
I would sell the epub.
How can I put a watermark on each page with "order number", "date of purchase" and "username".

I tried to search plugins or scripts php to integrate, but I found nothing.

Some idea?

Thank you

[jenkinhill]

So you are going to generate ePub archives on the fly adding the data to every page file before building the package? Never heard of anyone doing that before. Certainly not something that Joomla or VirtueMart could do.

[Studio 42]

If you use a PHP class to generate your Epub, you can add some information as order number ....
If you have already generated epub, this is more complex to do.