I'm implementing a PDF editor on UWP using PDFium as the base library. I cannot seem to find any proper way of adding/creating watermarks on a document.
I went through the PDFium source and spec documents but didn't find anything useful.
I tried to analyze some PDF documents with watermarks but it is unclear how they are created and couldn't find a common mapping too.
Could someone please help me understand how watermarks are added to PDF documents?
Any help is much appreciated. Thanks
pdfium don't support add watermark directly. You can add page object to implement.