Input and compilation/Accessibility

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Introduction

This page is added to summarize the requirements contained in Directive UE/2019/882 (https://eur-lex.europa.eu/eli/dir/2019/882/oj).

Since national legal documents have been released (by 28 June 2022) and their measures will be applied from 28 June 2025, it is important to know what the new requirements are.

Replacement or alternative texts

Replacement texts

The \pdfbackendactualtext (or its alias \pdfactualtext) allows to add a replacement text from what is being displayed.

With the following sample, a different sentence will be displayed form the one being stored as text (to copy and search for).

\starttext
Th\pdfbackendactualtext{is}{at} is only \pdfbackendactualtext{visible}{alternative} text.
\stoptext

As described by the PDF specification, ActualText is intended to be used to encode text displayed in a non-standard way.

It might be used at a character level (it doesn’t require full words).

Expansion of abbreviations or acronyms

To to enhace the automatic text-to-speech conversion, PDF allows the expansion of abbreviations or acronyms.

Synonyms may need to have this expansion, such as in:

\definesynonyms[test][tests][\infull]
\setupsynonyms[test][criterium=all]

\test{ITU}{International Telecommunication Union}
\test{MID}{Maritime Identification Digit}
\test{Ch}{Switzerland}

\starttext
   The \MID\ comes from the \ITU, an organisation in \infull{Ch}.
\stoptext

The PDF specification considers the expansion as a word or phrase substitution and a word break should separate it from the surrounding text (unlike ActualText, in both cases).

Alternate descriptions

The PDF specification includes a method to display alternate descriptions.

It is intended to provide human-readable text for items that not translate well into text (such as images or other similar items).

\pdfalternativetext enables this feature in ConTeXt. It might be invoked as:

\setupexternalfigures[location=default]
\starttext
\pdfalternativetext{\externalfigure[cow]}
    {alternate description}
\stopPDFalternativetext
\stoptext

Alternate descriptions are expected to be full words, so word separations should be placed by the user before and after the alternate descriptions.[1]

Footnotes

  1. This differs from replacement texts, that may be used to replace single characters (such as signatures).