PDF Association logo

Well-Tagged PDF (WTPDF)

Well-Tagged PDF (WTPDF) - Using Tagged PDF for Accessibility and Reuse in PDF 2.0

The primary purpose of this specification is to define how to represent electronic documents in PDF 2.0 files in a manner that allows the file to be reusable and accessible across a wide spectrum of possible use-cases.

There is a large overlap between the requirements for reuse and accessibility. However, some requirements are critical for reuse whereas others are critical for accessibility. This document clearly identifies the requirements for each use-case via a conformance level mechanism.

WTPDF identifies the components that shall, should or may be used in these contexts, as well as restrictions on their use. It includes a conformance level mechanism to empower software and document authors to target these use cases.

The specification is fully compatible with ISO 14289-2 (PDF/UA-2), so a file that conforms to the accessibility conformance level defined in this specification also conforms to the latest ISO standard for accessible PDF, and may be marked as such.

Both this document and PDF/UA-2 provide numerous improvements on PDF/UA-1, including:

  • comprehensive requirements for the new structure element types introduced in PDF 2.0
  • comprehensive requirements for structure element attributes;
  • comprehensive requirements for the use of annotations;
  • rules governing the inclusion of structure elements defined in PDF 1.7 as well as PDF 2.0;
  • detailed requirements for math, including support for MathML;
  • requirements for the use of the new Artifact structure element;
  • requirements for intra-document links leveraging the structure destinations feature introduced in PDF 2.0;
  • the use of PDF 2.0’s Associated Files feature to facilitate the integration of non-PDF content;
  • examples of semantically-significant attribute usage.

"If you support WTPDF you also support PDF/UA-2."

NOTE: We intended version 1.0.0 of this document to be a high-quality PDF/UA-1 file. With new capabilities such as the Arlington PDF Model, we have identified minor deviations from specification caused by various vendor tools. We are working closely with vendors to address these issues, and will issue a dot release once the tooling is corrected.

Subscribe here for the PDF Association’s periodic updates regarding new, updated, or corrected industry and ISO specifications for PDF technology.

$0.00