Read document structure and apply PDF accessibility tag?

[gobsmack]

I am working on a project to make existing PDF documents accessible. I am trying to switch from PdfSharp to PdfPig because it seems to handle metadata better. My goal is to read the document structure, and then add accessibility tags to the PDF.

I've got a pretty good start, using the PDFMerger. So, I can copy the input document to an output document with all the metadata. But I'm stuck on the tags (the whole point). I'm getting a tagged PDF. But there are no tags.

It looks like this is all written into PdfPig already. PdfPig can analyze the document structure. So, I wonder if there is a way to write the tags based on the document structure.

Am I missing something? Could somebody point me in the correct direction?

[gobsmack]

More specifically, I wonder if it's possible to create the tag structure based on the bookmark structure.