Tagged PDF

As of version 5.0 of PDFKit.NET you can create and consume tagged PDF documents.

What is tagged PDF?

A tagged PDF has additional information that is referred to as the logical structure of the PDF. The logical structure is a hierarchy of structure elements that exists separately from the visual content. The logical structure is associated with the visual content by bi-directional pointers. A piece of visual content is said to by tagged if such a pointer exists and the corresponding structure element is referred to as the tag.

The following Adobe Acrobat screenshot shows a piece of text being tagged as a paragraph:

Taggedpdf

Purpose of tagging

Tagged PDF allows the following types of applications:

  • Reflow content for small devices
  • Screen readers for visually impaired people
  • Searching, indexing and spell-checking
  • Conversion to other formats such as HTML