This document provides techniques for meeting the guidelines of the Accessibility Metadata Display Guide for Digital Publications 2.0. It provides practical examples on how to extract information from an EPUB package document and show it to end users.

Introduction

EPUB accessibility metadata

The metadata processed by these techniques is outlined in EPUB Accessibility 1.1 [[epub-a11y-11]]. It is found in the EPUB package document [[EPUB-33]].

Techniques for displaying accessibility metadata in other metadata formats can be found in the Display Techniques for Displaying Accessibility Metadata.

Implementation conventions

Heading structure

The algorithms defined in this document do not include instructions for outputting their respective headings because if a given technique does not result in any information (i.e., would output a statement that no information is available), the section may be omitted (i.e., no heading would be displayed). Whether there is any information to display is only known after an algorithm is processed, which would lead to the algorithms having to include instructions to remove headings.

The headings structure to use for the techniques is defined in the guidelines but is repeated here to help guide implementations. The headings are linked to the algorithm they are associated with.

  1. "Ways of reading"[ID: ways-of-reading-title]
  2. "Conformance"[ID: conformance-title]
  3. "Navigation"[ID: navigation-title]
  4. "Rich content"[ID: rich-content-title]
  5. "Hazards"[ID: hazards-title]
  6. "Accessibility summary"[ID: accessibility-summary-title]
  7. "Legal considerations"[ID: legal-considerations-title]
  8. "Additional accessibility information"[ID: additional-accessibility-information-title]

Coding conventions

The code conventions used in the provided code snippet follow a structure commonly found in programming languages like Python, Java, or C++. Here's an explanation of the conventions:

Conditionals and Control Flow:
IF, ELSE IF, and ELSE (in bold and capital letters) statements are used to define different conditions and the corresponding actions to be taken.
Operators:
Written operators (is present) are used to check if a particular code or codelist is present (or not) in the metadata record.
Logical operators:
Logical operators (AND, OR, NOT, in bold and capital letters) are used to combine conditions.
String Literals:
String literals are used to represent the text that should be displayed when a particular condition is met.
Variable Naming:
The terms like "property" and "value" are used in a way that suggests a variable or data structure representing the metadata record.
Indentation:
The code uses consistent indentation to define blocks of code within conditional statements. This is crucial for readability and maintaining a clear structure.
Readability:
The code is written in a way that is intended to be easily readable and understandable even by non-coders.

Node selectors

These techniques use XPath 1.0 expressions [[xpath-10]] to verify the presence of accessibility metadata in an EPUB package document and to select information from it. Some of the selectors can be optimized for processors that support newer versions of XPath (e.g., to match an element against a sequence of values rather than repeat the element for each possible value).

Translation of these XPath selectors may be necessary if the input record is transformed into another form, such as a JSON structure.

Output statements

The outputs provided in this document demonstrate the compact strings to display. For every text string, however, both a compact and descriptive option is available. These strings are provided in a JSON structure, as shown in the following example.

This document does not set a default output. Either the compact or descriptive statements can be presented to the end user, or they can even be provided the option to choose their own preference.

At the end of each output statement is an ID in brackets. This ID corresponds to a key in the JSON file containing both the compact and descriptive display statements (see the preceding example). To use the descriptive statement instead of the compact, simply select the "descriptive" subkey instead of the "compact" one associated with the ID.

The canonical English JSON file containing the compact and descriptive strings is available at https://github.com/w3c/publ-a11y/tree/main/a11y-meta-display-guide/2.0/draft/localizations/en-US.

Common functions

In this section we define the functions common to all techniques, which are called by them during execution.

Preprocessing

Before working directly with the metadata we must read the metadata in the Package document (package document) inside the EPUB. This is a common starting point for all techniques that allows us to query the metadata directly.

This algorithm takes the package_document_as_text argument: a UTF-8 string representing the Package document.

To generate the internal representation, run the following steps:

  1. LET package_document be the DOM tree that results from parsing package_document_as_text using an XML DOM parser.
  2. Return package_document.

Check for node

Many of the techniques rely on checking for the presence or absence of metadata in the metadata section of the Package document.

This algorithm takes:

To check for node, run the following steps:

  1. IF package_document contains path: THEN return True.
  2. ELSE return False.

Techniques

Ways of reading

This technique relates to the Ways of reading accessibility display field.

This algorithm takes the package_document_as_text argument: a UTF-8 string representing the Package document.

Visual adjustments

This technique relates to the Visual adjustments accessibility display field.

Understanding the variables
all_textual_content_can_be_modified

If true, it indicates that accessibilityFeature="displayTransformability" is present in the package document.

All textual content can be modified means that the digital publication does not restrict the ability of users to modify and reflow the display of any textual content to the full extent allowed by the reading system (i.e. to change the text size or typeface, line height and word spacing, colors).

is_fixed_layout

If true, it indicates that layout="pre-paginated" is present in the package document.

Fixed format means that digital publication is in fixed format (e.g. EPUB Fixed Layout).

Variables setup
  • LET package_document be the result of calling preprocessing given package_document_as_text.
  • LET all_textual_content_can_be_modified be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityFeature" and normalize-space()="displayTransformability"].
  • LET is_fixed_layout be the result of calling check for node on package_document, /package/metadata/meta[@property="rendition:layout" and normalize-space()="pre-paginated"].
Instructions
  1. IF all_textual_content_can_be_modified: THEN display "Appearance can be modified"[ID: ways-of-reading-visual-adjustments-modifiable].
  2. ELSE IF is_fixed_layout: THEN display "Appearance cannot be modified"[ID: ways-of-reading-visual-adjustments-unmodifiable].
  3. ELSE display "No information about appearance modifiability is available"[ID: ways-of-reading-visual-adjustments-unknown].

Supports nonvisual reading

This technique relates to the Supports nonvisual reading accessibility display field.

Understanding the variables
all_necessary_content_textual

If true, it indicates that there is only a single access mode of textual or accessModeSufficient="textual" (all main content is provided in textual form) is present in the package document.

audio_only_content

If true, it indicates that there is only a single access mode of auditory (an audiobook).

some_sufficient_text

If true, it indicates that sufficient access mode metadata indicates that the content is at least partially readable in textual form (i.e., "textual" is one of a set of sufficient access modes).

textual_alternatives

If true, it indicates that at least one of the following is present in the package document:

  • accessibilityFeature="alternativeText";
  • accessibilityFeature="longDescription";
  • accessibilityFeature="describedMath";
  • accessibilityFeature="transcript";

This means that there are textual alternatives for the non-textual content.

visual_only_content

If true, it indicates that there is only a single access mode of visual and there are no sufficient access modes that include textual (e.g., comics and manga with no alternative text).

Variables setup
  1. LET package_document be the result of calling preprocessing given package_document_as_text.
  2. LET all_necessary_content_textual be the result of calling check for node on package_document, /package/metadata/meta[(@property="schema:accessMode" and normalize-space() = "textual" and count(//meta[@property="schema:accessMode"]) = 1) or (@property="schema:accessModeSufficient" and normalize-space()="textual")].
  3. LET audio_only_content be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessMode" and normalize-space() = "auditory" and count(//meta[@property="schema:accessMode"]) = 1].
  4. LET some_sufficient_text be the result of calling check for node on package_document, /package/metadata/meta[(@property="schema:accessMode" and contains(normalize-space(), "textual")) or (@property="schema:accessModeSufficient" and contains(normalize-space(), "textual"))].
  5. LET textual_alternatives be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityFeature" and (normalize-space() = "longDescription" or normalize-space() = "alternativeText" or normalize-space() = "describedMath" or normalize-space() = "transcript")].
  6. LET visual_only_content be the result of calling check for node on package_document, /package/metadata/meta[(@property="schema:accessMode" and normalize-space() = "visual" and count(//meta[@property="schema:accessMode"]) = 1) and not(//meta[@property="schema:accessModeSufficient" and contains(normalize-space(), "textual")])].
Instructions
  1. IF all_necessary_content_textual: THEN display "Readable in read aloud or dynamic braille"[ID: ways-of-reading-nonvisual-reading-readable].
  2. ELSE IF some_sufficient_text OR textual_alternatives: THEN display "Not fully readable in read aloud or dynamic braille"[ID: ways-of-reading-nonvisual-reading-not-fully].
  3. ELSE IF audio_only_content or visual_only_content: THEN display "Not readable in read aloud or dynamic braille"[ID: ways-of-reading-nonvisual-reading-none].
  4. ELSE display "No information about nonvisual reading is available"[ID: ways-of-reading-nonvisual-reading-no-metadata].
  5. IF textual_alternatives: THEN display "Has alternative text"[ID: ways-of-reading-nonvisual-reading-alt-text].

Prerecorded audio

This technique relates to the Prerecorded audio accessibility display field.

Understanding the variables
all_content_audio

If true, it indicates that the accessModeSufficient="auditory" (all main content is provided in audio form) is present in the package document.

audio_content

If true, it indicates that the accessMode="auditory" is present in the package document.

This indicates that prerecorded audio content is included as part of the work.

synchronised_pre_recorded_audio

If true, it indicates that the accessibilityFeature="synchronizedAudioText" is present in the package document.

This indicates that text-synchronised prerecorded audio narration (natural or synthesized voice) is included for substantially all textual matter, including all alternative descriptions, e.g. via a SMIL media overlay.

Variables setup
  • LET package_document be the result of calling preprocessing given package_document_as_text.
  • LET all_content_audio be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessModeSufficient" and normalize-space()="auditory"].
  • LET audio_content be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessMode" and normalize-space()="auditory"].
  • LET synchronised_pre_recorded_audio be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityFeature" and normalize-space()="synchronizedAudioText"].
Instructions
  1. IF synchronised_pre_recorded_audio: THEN display "Prerecorded audio synchronized with text"[ID: ways-of-reading-prerecorded-audio-synchronized].
  2. ELSE IF all_content_audio: THEN display "Prerecorded audio only"[ID: ways-of-reading-prerecorded-audio-only].
  3. ELSE IF audio_content: THEN display "Prerecorded audio clips"[ID: ways-of-reading-prerecorded-audio-complementary].
  4. ELSE either omit this display field if metadata is missing or display "No information about prerecorded audio is available"[ID: ways-of-reading-prerecorded-audio-no-metadata].

Conformance

This technique relates to the Conformance accessibility display field.

This algorithm takes the package_document_as_text argument: a UTF-8 string representing the Package document.

Understanding the variables

certifier

Returns the description of a11y:certifiedBy if present in the package document.

This means that the name of the organization responsible for compliance testing and certification of the product is present.

certifier_credentials

Returns the description of a11y:certifierCredential if present in the package document.

This means that the the URL of a web page belonging to an organization responsible for compliance testing and certification of the product is present – typically a ‘home page’ or a page describing the certification scheme itself.

certification_date

Returns the description of dcterms:date if that date property is associated with the a11y:certifiedBy (Latest accessibility assessment date) if present in the package document.

This means that the date of the latest assessment or re-assessment of the accessibility of the product is present.

certifier_report

Returns the description of a11y:certifierReport (Compliance web page for detailed accessibility information) if present in the package document.

This means that is present the URL of a compliance web page for detailed accessibility information. The web page should be maintained by an independent compliance scheme or testing organization. Note the web page may include information about specific national requirements or voluntary conformance reports.

epub_version

If set, provides the version of the EPUB Accessibility specification the publication conforms to.

epub10_wcag20a

If set, indicates that a conformance claim to the EPUB Accessibility 1.0 specification at WCAG 2.0 Level A.

epub10_wcag20aa

If set, indicates that a conformance claim to the EPUB Accessibility 1.0 specification at WCAG 2.0 Level AA.

epub10_wcag20aaa

If set, indicates that a conformance claim to the EPUB Accessibility 1.0 specification at WCAG 2.0 Level AAA.

wcag_version

If set, provides the WCAG 2 conformance level claimed.

Variables setup

Instructions

  1. IF NOT epub_version AND NOT wcag_version: THEN display "No information is available"[ID: conformance-no].
  2. ELSE:
    1. IF wcag_level == 'AAA': THEN display "This publication exceeds accepted accessibility standards"[ID: conformance-aaa].
    2. ELSE IF wcag_level == 'AA': THEN display "This publication meets accepted accessibility standards"[ID: conformance-aa].
    3. ELSE IF wcag_level == 'A': THEN display "This publication meets minimum accessibility standards"[ID: conformance-a].
    4. ELSE THEN display "Conformance to accepted standards for accessibility of this publication cannot be determined"[ID: conformance-unknown-standard].
    5. IF certifier is NOT empty: THEN
      1. display "The publication was certified by "[ID: conformance-certifier]
      2. display certifier.
    6. IF certifier_credentials is NOT empty: THEN
      1. display "The certifier's credential is "[ID: conformance-certifier-credentials]
      2. IF certifier_credentials is a URL. THEN display certifier_credentials as a link.
      3. ELSE display certifier_credentials as text.

        4. If the certifier metadata value is a text-based badge or a credential, then only the text is displayed. If the badge or credential is expressed as a URL, then the URL can be made a link for users to access. The display of image logos or badges is typically arranged between the certifier and the distributor. The distributor would be responsible for identifying the certifier's text or link credential and replacing it with the image or linked image.

    7. The instructions from here on define the output for the detailed conformance information. Refer to the Detailed Conformance section in the guidelines for more information on how to present these strings.

      Display "This publication claims to meet"[ID: conformance-details-claim].
      1. IF epub_version == '1.0': THEN display " EPUB Accessibility 1.0"[ID: conformance-details-epub-accessibility-1-0].
      2. ELSE IF epub_version == '1.1': THEN display " EPUB Accessibility 1.1"[ID: conformance-details-epub-accessibility-1-1].
      3. IF wcag_version == '2.2': THEN display " WCAG 2.2"[ID: conformance-details-wcag-2-2].
      4. ELSE IF wcag_version == '2.1': THEN display " WCAG 2.1"[ID: conformance-details-wcag-2-1].
      5. ELSE IF wcag_version == '2.0': THEN display " WCAG 2.0"[ID: conformance-details-wcag-2-0].
      6. IF wcag_level == 'AAA': THEN display " Level AAA"[ID: conformance-details-level-aaa].
      7. ELSE IF wcag_level == 'AA': THEN display " Level AA"[ID: conformance-details-level-aa].
      8. ELSE IF wcag_level == 'A': THEN display " Level A"[ID: conformance-details-level-a].
    8. IF certification_date THEN:
      1. display "The publication was certified on "[ID: conformance-details-certification-info]
      2. display certification_date.
    9. IF certifier_report: THEN display "For more information refer to the certifier's report"[ID: conformance-details-certifier-report] as a named link with certifier_report as the URL used.

Rich content

This technique relates to the Rich content accessibility display field.

This algorithm takes the package_document_as_text argument: a UTF-8 string representing the Package document.

Understanding the variables

chemical_formula_as_latex

If true, it indicates that accessibilityFeature="latex-chemistry" is present in the package document.

This means that there is a positive indication that the chemical formulae are presented using Latex and works with compatible assistive technology.

chemical_formula_as_mathml

If true, it indicates that accessibilityFeature="MathML-chemistry" is present in the package document.

This means that there is a positive indication that the chemical formulae are presented using MathML and works with compatible assistive technology.

closed_captions

If true, it indicates that accessibilityFeature="closedCaptions" is present in the package document.

This means that the audio content of a video can be seen via closed captions that can be turned on or off by the viewer and which will be a separate file from the video itself.

contains_charts_diagrams

If true, it indicates that accessMode="chartOnVisual" is present in the package document.

This means that there is a positive indication that the product has some information conveyed via some form of illustration, such as a graph, a chart, a diagram, a figure, etc).

contains_chemical_formula

If true, it indicates that accessMode="chemOnVisual" is present in the package document.

This means that there is a positive indication that the publication contains chemical notations, formulae.

contains_math_formula

If true, it indicates that accessibilityFeature="describedMath" is present in the package document.

This means that there is a positive indication that the publication contains mathematical notation, equations, formulae.

full_alternative_textual_descriptions

If true, it indicates that accessibilityFeature="longDescriptions" is present in the package document.

This means that there is a positive indication that a full alternative textual description has been supplied for all of the graphs, charts, diagrams, or figures necessary to understand the content.

math_formula_as_latex

If true, it indicates that accessibilityFeature="latex" is present in the package document.

This means that there is a positive indication that the math is presented using LaTeX and works with compatible assistive technology.

math_formula_as_mathml

If true, it indicates that accessibilityFeature="MathML" is present in the package document.

This means that there is a positive indication that all mathematical content is presented using MathML and works with compatible assistive technology.

open_captions

If true, it indicates that accessibilityFeature="openCaptions" is present in the package document.

This means that the audio content of a video can be seen via open captions, which means they cannot be turned off and are always visible when the video plays.

transcript

If true, it indicates that accessibilityFeature="transcript" is present in the package document.

This means that a transcript of the audio content of the product is supplied with it.

Variables setup

Instructions

  1. IF full_alternative_textual_descriptions: THEN display "Information-rich images are described by extended descriptions"[ID: rich-content-extended].
  2. IF chemical_formula_as_latex: THEN display "Chemical formulas in LaTeX"[ID: rich-content-accessible-chemistry-as-latex].
  3. IF chemical_formula_as_mathml: THEN display "Chemical formulas in MathML"[ID: rich-content-accessible-chemistry-as-mathml].
  4. IF contains_math_formula: THEN display "Text descriptions of math are provided"[ID: rich-content-accessible-math-described].
  5. IF math_formula_as_latex: THEN display "Math as LaTeX"[ID: rich-content-accessible-math-as-latex].
  6. IF math_formula_as_mathml: THEN display "Math as MathML"[ID: rich-content-accessible-math-as-mathml].
  7. IF closed_captions: THEN display "Videos have closed captions"[ID: rich-content-closed-captions].
  8. IF open_captions: THEN display "Videos have open captions"[ID: rich-content-open-captions].
  9. IF transcript: THEN display "Transcript(s) provided"[ID: rich-content-transcript].
  10. IF NOT (math_formula_as_mathml OR math_formula_as_latex OR (contains_math_formula AND full_alternative_textual_descriptions) OR chemical_formula_as_mathml OR full_alternative_textual_descriptions OR closed_captions OR open_captions OR transcript): THEN either omit this display field if metadata is missing or display "No information is available"[ID: rich-content-unknown].

Hazards

This technique relates to the Hazards accessibility display field.

This algorithm takes the package_document_as_text argument: a UTF-8 string representing the Package document.

Understanding the variables

flashing_hazard

If true, it indicates that accessibilityHazard="flashing" is present in the package document.

This means that there is a positive indication in the accessibility metadata within the EPUB confirming that the product has a flashing hazard which must be displayed.

motion_simulation_hazard

If true, it indicates that accessibilityHazard="motionSimulation" is present in the package document.

This means that there is a positive indication in the accessibility metadata within the EPUB confirming that the product has a motion simulation hazard which must be displayed.

no_flashing_hazard

If true, it indicates that accessibilityHazard="noFlashingHazard" is present in the package document.

This means there is a positive indication in the accessibility metadata within the EPUB confirming there are no flashing hazards associated with this product.

no_hazards_or_warnings_confirmed

If true, it indicates that accessibilityHazard="none" is present in the package document.

This means there is a positive indication in the accessibility metadata within the EPUB confirming there are no associated hazard warnings with this product.

no_motion_hazard

If true, it indicates that accessibilityHazard="noMotionSimulationHazard" is present in the package document.

This means there is a positive indication in the accessibility metadata within the EPUB confirming there are no motion simulation hazards associated with this product.

no_sound_hazard

If true, it indicates that accessibilityHazard="noSoundHazard" is present in the package document.

This means there is a positive indication in the accessibility metadata within the EPUB confirming there are no sound hazards associated with this product.

sound_hazard

If true, it indicates that accessibilityHazard="Sound" is present in the package document.

This means that there is a positive indication in the accessibility metadata within the EPUB confirming that the product has a sound hazard which must be displayed.

unknown_flashing_hazard

If true, it indicates that accessibilityHazard="unknownFlashingHazard" is present in the package document.

This means the presence of flashing hazards could not be determined.

unknown_if_contains_hazards

If true, it indicates that accessibilityHazard="unknown" is present in the package document.

This means that the product has not been assessed for hazards and there is no information about potential hazards.

unknown_motion_hazard

If true, it indicates that accessibilityHazard="unknownMotionSimulationHazard" is present in the package document.

This means the presence of motion simulation hazards could not be determined.

unknown_sound_hazard

If true, it indicates that accessibilityHazard="unknownSoundHazard" is present in the package document.

This means the presence of sound hazards could not be determined.

Variables setup

Instructions

  1. IF no_hazards_or_warnings_confirmed OR (no_flashing_hazard AND no_motion_hazard AND no_sound_hazard): THEN display "No hazards"[ID: hazards-none].
  2. ELSE IF unknown_if_contains_hazards OR (unknown_flashing_hazard AND unknown_motion_hazard AND unknown_sound_hazard): THEN display "The presence of hazards is unknown"[ID: hazards-unknown].
  3. ELSE IF flashing_hazard OR motion_simulation_hazard OR sound_hazard OR no_flashing_hazard OR no_motion_hazard OR no_sound_hazard OR unknown_flashing_hazard OR unknown_motion_hazard OR unknown_sound_hazard: THEN
    1. IF flashing_hazard: THEN display "Flashing content"[ID: hazards-flashing].
    2. IF motion_simulation_hazard: THEN display "Motion simulation"[ID: hazards-motion].
    3. IF sound_hazard: THEN display "Sounds"[ID: hazards-sound].
    4. IF unknown_flashing_hazard: THEN display "Flashing hazards not known"[ID: hazards-flashing-unknown].
    5. IF unknown_motion_simulation_hazard: THEN display "Motion simulation hazards not known"[ID: hazards-motion-unknown].
    6. IF unknown_sound_hazard: THEN display "Sound hazards not known"[ID: hazards-sound-unknown].
    7. IF no_flashing_hazard: THEN display "No flashing hazards"[ID: hazards-flashing-none].
    8. IF no_motion_simulation_hazard: THEN display "No motion simulation hazards"[ID: hazards-motion-none].
    9. IF no_sound_hazard: THEN display "No sound hazards"[ID: hazards-sound-none].
  4. ELSE either omit this display field if metadata is missing or display "No information is available"[ID: hazards-no-metadata].

Accessibility summary

This technique relates to the Accessibility summary accessibility display field.

This algorithm takes the package_document_as_text argument: a UTF-8 string representing the Package document.

Being human-written, the accessibility summary will appear in the original language of the publication. Therefore it is necessary to take care of setting up the correct language tag information.

Accessibility summaries were necessary when no systems exposed computed accessibility metadata. With more systems now displaying this information, much of the accessibility summary may be redundant. Publishers should focus on adding information not provided within the computed metadata, such as specifying where in a video file a flashing hazard exists, or noting the reason why they failed to meet WCAG-AA due to color contrast issues in the Appendix.

Understanding the variables

accessibility_summary

Contains the accessibilitySummary from the package document if it exists; otherwise, it will be blank.

This means there is a human-written text containing a short explanatory summary of the accessibility of the product or the URL of a web page comprising such a summary. Summarizes the already existent information and may add information that the publisher could not express with the other codes.

lang_attribute_accessibility_summary

Returns the lang attribute of the node containing the accessibility_summary, or the lang attribute of the nearest ancestor.

This is the language code in which the text of the Accessibility summary was written.

language_of_text

Returns the value of nearest "language" if present in the package document.

This indicates the main language of the content and therefore the most probable language of accessibility summary.

Variables setup

Instructions

  1. IF lang_attribute_accessibility_summary is NOT empty: THEN LET language_accessibility_summary be the value of lang_attribute_accessibility_summary.
  2. ELSE LET language_accessibility_summary be the value of language_of_text.
  3. IF accessibility_summary is NOT empty: THEN display the content of accessibility_summary with language_accessibility_summary as language.
  4. ELSE either omit this display field if metadata is missing or display "No information is available"[ID: accessibility-summary-no-metadata].

Additional accessibility information

This technique relates to the Additional accessibility information accessibility display field.

This algorithm takes the package_document_as_text argument: a UTF-8 string representing the Package document.

Understanding the variables

aria

If true, it indicates that accessibilityFeature="aria" is present in the package document.

This means that the use of ARIA, including DPUB ARIA is used to improve the semantic markup of the publication.

audio_descriptions

If true, it indicates that accessibilityFeature="audioDescriptions" is present in the package document.

This means that there is an audio descriptions track available for video content.

braille

If true, it indicates that accessibilityFeature="braille" is present in the package document.

This means that there is braille available within the publication.

full_ruby_annotations

If true, it indicates that accessibilityFeature="fullRubyAnnotations" is present in the package document.

This means that ruby annotations are attached to every CJK ideographic character in the content. Ruby annotations are used as pronunciation guides for the logographic characters for languages like Chinese or Japanese. They make difficult CJK ideographic characters more accessible.

high_contrast_between_foreground_and_background_audio

If true, it indicates that accessibilityFeature="highContrastAudio" is present in the package document.

This means that foreground audio content (eg voice) is presented with no or low background noise (eg ambient sounds, music), at least 20dB below the level of the foreground, or background noise can be switched off (eg via an alternative audio track). Brief and occasional sound effects may be as loud as foreground voice so long as they are isolated from the foreground.

high_contrast_between_text_and_background

If true, it indicates that accessibilityFeature="highContrastDisplay" is present in the package document.

This means that body text is presented with a contrast ratio of at least 4.5:1 (or 3:1 for large/heading text).

large_print

If true, it indicates that accessibilityFeature="largePrint" is present in the package document.

This means that the e-publication has been formatted to meet large print guidelines.

page_break_markers

If true, it indicates that accessibilityFeature="pageBreakMarkers" is present in the package document.

This means that the publication contains references to the page numbering.

ruby_annotations

If true, it indicates that accessibilityFeature="rubyAnnotations" is present in the package document.

This means that ruby annotations are attached to some but not all CJK ideographic characters in the content.

sign_language

If true, it indicates that accessibilityFeature="signLanguage" is present in the package document.

This means that a full signing of audio content of the product is supplied with the video file.

tactile_graphic

If true, it indicates that accessibilityFeature="tactileGraphic" is present in the package document.

This means that there is tactile graphic(s) contained within this publication.

tactile_object

If true, it indicates that accessibilityFeature="tactileObject" is present in the package document.

This means that there is tactile 3D object(s) contained within this publication.

text_to_speech_hinting

If true, it indicates that accessibilityFeature="ttsMarkup" is present in the package document.

This means that text-to-speech has been optimized through provision of PLS lexicons, SSML or CSS Speech synthesis hints or other speech synthesis markup languages or hinting.

Variables setup

Instructions

  1. IF page_break_markers: THEN display "Page breaks included"[ID: additional-accessibility-information-page-breaks].
  2. IF aria: THEN display "ARIA roles included"[ID: additional-accessibility-information-aria].
  3. IF audio_descriptions: THEN display "Audio descriptions"[ID: additional-accessibility-information-audio-descriptions].
  4. IF braille: THEN display "Braille"[ID: additional-accessibility-information-braille].
  5. IF full_ruby_annotations: THEN display "Full ruby annotations"[ID: additional-accessibility-information-full-ruby-annotations].
  6. IF high_contrast_between_foreground_and_background_audio: THEN display "High contrast between foreground and background audio"[ID: additional-accessibility-information-high-contrast-between-foreground-and-background-audio] .
  7. IF high_contrast_between_text_and_background: THEN display "High contrast between foreground text and background"[ID: additional-accessibility-information-high-contrast-between-text-and-background].
  8. IF large_print: THEN display "Large print"[ID: additional-accessibility-information-large-print].
  9. IF ruby_annotations: THEN display "Some Ruby annotations"[ID: additional-accessibility-information-ruby-annotations].
  10. IF sign_language: THEN display "Sign language"[ID: additional-accessibility-information-sign-language].
  11. IF tactile_graphic: THEN display "Tactile graphics included"[ID: additional-accessibility-information-tactile-graphics].
  12. IF tactile_object: THEN display "Tactile 3D objects"[ID: additional-accessibility-information-tactile-objects].
  13. IF text_to_speech_hinting: THEN display "Text-to-speech hinting provided"[ID: additional-accessibility-information-text-to-speech-hinting].

Change log

This section identifies substantive changes between versions. For a list of all changes, refer to the issue tracker.

Changes since the 2025-02-20 Draft Community Group Report