Abstract

The Graphics Accessibility API Mappings [GRAPHICS-AAM] defines how user agents map the WAI-ARIA Graphics Module [GRAPHICS-ARIA] markup to platform accessibility APIs. It is intended for user agent developers responsible for accessibility in their user agent so that they can support the accessibility of graphics such as that created for [SVG] or [HTML5].

The implementation of this specification in user agents enables authors to produce more accessible graphics by conveying common graphics semantics to assistive technologies. It provides Accessibility API Mapping guidance for the roles defined in the WAI-ARIA Graphics Module [GRAPHICS-ARIA].

The Graphics Accessibility API Mappings is part of the WAI-ARIA suite described in the WAI-ARIA Overview.

Status of This Document

This section describes the status of this document at the time of its publication. Other documents may supersede this document. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at https://www.w3.org/TR/.

This is a First Public Working Draft of Graphics Accessibility API Mappings 1.0 by the SVG Accessibility Task Force, a joint task force of the Accessible Rich Internet Applications Working Group and the SVG Working Group. It provides guidance for mapping roles in WAI-ARIA Graphics Module [GRAPHICS-ARIA] to accessibility APIs, and complements SVG-specific mappings in the SVG Accessibility API Mappings [SVG-AAM]. It extends Core Accessibility Mappings 1.1 [CORE-AAM], and is part of a suite of similar technology-specific Accessibility API Mappings specifications.

Feedback on any aspect of the specification is accepted. For this publication, the SVG Accessibility Task Force particularly seeks feedback on the following questions:

To comment, file an issue in the W3C ARIA GitHub repository, using the "graphics" label in the issue. If this is not feasible, send email to public-svg-a11y@w3.org (comment archive). Comments are requested by 30 September 2016. In-progress updates to the document may be viewed in the publicly visible editors' draft.

This document was published by the Accessible Rich Internet Applications Working Group and the SVG Working Group as a Working Draft.

Publication as a First Public Working Draft does not imply endorsement by the W3C Membership. This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.

This document was produced by groups operating under the 5 February 2004 W3C Patent Policy. W3C maintains a public list of any patent disclosures (Accessible Rich Internet Applications Working Group) and a public list of any patent disclosures (SVG Working Group) made in connection with the deliverables of each group; these pages also include instructions for disclosing a patent. An individual who has actual knowledge of a patent which the individual believes contains Essential Claim(s) must disclose the information in accordance with section 6 of the W3C Patent Policy.

This document is governed by the 1 September 2015 W3C Process Document.

1. Introduction §

This section is non-normative.

The Graphics Accessibility API Mappings specification provides role mappings for the roles in the WAI-ARIA Graphics Module [GRAPHICS-ARIA].

For web documents and applications, the essential semantic information is encapsulated within the Document Object Model (DOM). Assistive technologies obtain this information from the user agent, which maps elements and attributes to the platform Accessibility API.

The original suite of element semantics defined by WAI-ARIA 1.0 only considered graphics as individual embedded images, with no interactivity or meaningful semantic structure. It was therefore not sufficient for communicating complex graphics, such as labelled diagrams or data charts, or for interactive graphics. The WAI-ARIA Graphics Module defines a core set of three roles that can convey the structure of a graphic. This specification defines how user agents should expose those roles to the accessibility APIs currently in use, so that the semantic information is available to assistive technologies that use those APIs.

For an introduction to WAI-ARIA, see the WAI-ARIA Overview. It is part of a set of resources that define and support the WAI-ARIA specification, including the following documents:

2. Conformance §

As well as sections marked as non-normative, all authoring guidelines, diagrams, examples, and notes in this specification are non-normative. Everything else in this specification is normative.

The key words MAY, MUST, MUST NOT, OPTIONAL, RECOMMENDED, REQUIRED, SHALL, SHALL NOT, and SHOULD are to be interpreted as described in [RFC2119].

This specification indicates whether a section is normative or informative and the classification applies to the entire section. A statement "This section is normative" or "This section is informative" applies to all sub-sections of that section.

Normative sections provide requirements that user agents must follow for an implementation to conform to this specification. The keywords MUST, MUST NOT, REQUIRED, SHALL, SHALL NOT, SHOULD, RECOMMENDED, MAY, and OPTIONAL in this document are to be interpreted as described in Keywords for use in RFCs to indicate requirement levels [RFC2119]. RFC-2119 keywords are formatted in uppercase and contained in a strong element with class="rfc2119". When the keywords shown above are used, but do not share this format, they do not convey formal information in the RFC 2119 sense, and are merely explanatory, i.e., informative. As much as possible, such usages are avoided in this specification.

Informative sections provide information useful to understanding the specification. Such sections may contain examples of recommended practice, but it is not required to follow such recommendations in order to conform to this specification.

3. Important Terms §

While some terms are defined in place, the following definitions are used throughout this document.

Accessibility API

Operating systems and other platforms provide a set of interfaces that expose information about objects and events to assistive technologies. Assistive technologies use these interfaces to get information about and interact with those widgets. Examples of accessibility APIs are Microsoft Active Accessibility [MSAA], Microsoft User Interface Automation [UI-AUTOMATION], MSAA with UIA Express [UIA-EXPRESS], the Mac OS X Accessibility Protocol [AXAPI], the Linux/Unix Accessibility Toolkit [ATK] and Assistive Technology Service Provider Interface [AT-SPI], and IAccessible2 [IAccessible2].

Assistive Technologies

Hardware and/or software that:

  • relies on services provided by a user agent to retrieve and render Web content
  • works with a user agent or web content itself through the use of APIs, and
  • provides services beyond those offered by the user agent to facilitate user interaction with web content by people with disabilities

This definition may differ from that used in other documents.

Examples of assistive technologies that are important in the context of this document include the following:

  • screen magnifiers, which are used to enlarge and improve the visual readability of rendered text and images;
  • screen readers, which are most-often used to convey information through synthesized speech or a refreshable Braille display;
  • text-to-speech software, which is used to convert text into synthetic speech;
  • speech recognition software, which is used to allow spoken control and dictation;
  • alternate input technologies (including head pointers, on-screen keyboards, single switches, and sip/puff devices), which are used to simulate the keyboard;
  • alternate pointing devices, which are used to simulate mouse pointing and clicking.
Attribute

In this specification, attribute is used as it is in markup languages. Attributes are structural features added to elements to provide information about the states and properties of the object represented by the element.

Class

A set of instance objects that share similar characteristics.

Element

In this specification, element is used as it is in markup languages. Elements are the structural elements in markup language that contains the data profile for objects.

Event

A programmatic message used to communicate discrete changes in the state of an object to other objects in a computational system. User input to a web page is commonly mediated through abstract events that describe the interaction and can provide notice of changes to the state of a document object. In some programming languages, events are more commonly known as notifications.

Informative

Content provided for information purposes and not required for conformance. Content required for conformance is referred to as normative.

Normative

Required for conformance. By contrast, content identified as informative or "non-normative" is not required for conformance.

Object

In the context of user interfaces, an item in the perceptual user experience, represented in markup languages by one or more elements, and rendered by user agents.

In the context of programming, the instantiation of one or more classes and interfaces which define the general characteristics of similar objects. An object in an accessibility API may represent one or more DOM objects. Accessibility APIs have defined interfaces that are distinct from DOM interfaces.
Property

Attributes that are essential to the nature of a given object, or that represent a data value associated with the object. A change of a property may significantly impact the meaning or presentation of an object. Certain properties (for example, aria-multiline) are less likely to change than states, but note that the frequency of change difference is not a rule. A few properties, such as aria-activedescendant, aria-valuenow, and aria-valuetext are expected to change often. See clarification of states versus properties.

Role

Main indicator of type. This semantic association allows tools to present and support interaction with the object in a manner that is consistent with user expectations about other objects of that type.

Semantics

The meaning of something as understood by a human, defined in a way that computers can process a representation of an object, such as elements and attributes, and reliably represent the object in a way that various humans will achieve a mutually consistent understanding of the object.

State

A state is a dynamic property expressing characteristics of an object that may change in response to user action or automated processes. States do not affect the essential nature of the object, but represent data associated with the object or user interaction possibilities. See clarification of states versus properties.

User Agent

Any software that retrieves, renders and facilitates end user interaction with Web content. This definition may differ from that used in other documents.

Widget

Discrete user interface object with which the user can interact. Widgets range from simple objects that have one value or operation (e.g., check boxes and menu items), to complex objects that contain many managed sub-objects (e.g., trees and grids).

4. Mapping WAI-ARIA to Accessibility APIs §

4.1 General rules for exposing WAI-ARIA semantics §

This section MUST conform to General rules for exposing WAI-ARIA semantics in [CORE-AAM].

5. Conflicts between native markup semantics and WAI-ARIA §

User agents MUST conform to Conflicts between native markup semantics and WAI-ARIA in [CORE-AAM].

6. Exposing attributes that do not directly map to accessibility API properties §

User agents MUST conform to Exposing attributes that do not directly map to accessibility API properties in [CORE-AAM].

7. Role mapping §

Platform accessibility APIs traditionally have had a finite set of predefined roles that are expected by assistive technologies on that platform and only one or two roles may be exposed. In contrast, WAI-ARIA allows multiple roles to be specified as an ordered set of space-separated valid role tokens. The additional roles are fallback roles similar to the concept of specifying multiple fonts in case the first choice font type is not supported.

7.1 General Rules §

User agents MUST conform to the Role Mapping General Rules accessibility API computational requirements in [CORE-AAM].

7.2 Role Mapping Table §

This section defines how roles in digital publishing map to platform accessibility APIs based on their native host language semantics and when WAI-ARIA roles are applied. This section refers directly to the Core Accessibility API Mappings specification.

Table describing mapping of WAI-ARIA roles to accessibility APIs.
WAI-ARIA Role MSAA + IAccessible2 Role + Other IAccessible2 Features UIA Control Type + Other Features ATK/AT-SPI Role AXAPI
graphics-document

ROLE_SYSTEM_DOCUMENT + STATE_SYSTEM_READONLY

IAccessible2: Object attribute xml-roles:graphics-document.

  • Expose as text string 'graphics-document' in AriaRole.
  • Control type/role is 'Document'.

Expose ROLE_DOCUMENT_FRAME + do not expose STATE_EDITABLE. Expose object Attribute xml-roles:graphics-document.

AXRole: AXGroup
AXSubrole: ? AXGraphicsDoc
AXRoleDescription: 'graphics document'
graphics-object ROLE_SYSTEM_GROUPING +

IAccessible2: Object attribute xml-roles:graphics-obj.

  • Expose as text string 'graphics-object' in AriaRole.
  • Control type/role is 'graphics-object'

Expose ROLE_GROUP and object attribute xml-roles:graphics-object.

AXRole: AXGroup
AXSubrole: ? AXGraphicsObject
AXRoleDescription: 'graphics object'
graphics-symbol ROLE_SYSTEM_GRAPHIC

IAccessible2: Object attribute xml-roles:graphics-symbol.

  • Expose as text string 'graphics-symbol' in AriaRole.
  • Control type/role is 'graphics-symbol'.

Expose ROLE_IMAGE and object attribute xml-roles:graphics-symbol.

AXRole: AX
AXSubrole: ? AXSymbol
AXRoleDescription: 'graphics symbol'

A. Appendices §

A.1 References §

This section is informative.

Placeholder for references

A.2 Acknowledgments §

This section is non-normative.

The following people contributed to the development of this document.

A.2.1 Participants active in the ARIA WG at the time of publication §

  • Ann Abbott (IBM Corporation)
  • Michiel Bijl (The Paciello Group)
  • Christy Blew (University of Illinois at Urbana-Champaign)
  • David Bolter (Mozilla Foundation)
  • Michael Cooper (W3C/MIT)
  • James Craig (Apple Inc.)
  • Joanmarie Diggs (Igalia)
  • Fred Esch (IBM Corporation)
  • Steve Faulkner (The Paciello Group)
  • John Foliot (Invited Expert)
  • Bryan Garaventa (SSB BART Group)
  • Matt Garrish (DAISY Consortium)
  • Billy Gregory (The Paciello Group)
  • Karl Groves (The Paciello Group)
  • Jon Gunderson (University of Illinois at Urbana-Champaign)
  • Markus Gylling (DAISY Consortium)
  • Markku Hakkinen (Educational Testing Service)
  • Katie Haritos-Shea (Knowbility)
  • Susann Keohane (IBM Corporation)
  • Matthew King (Facebook)
  • Jason Kiss (Department of Internal Affairs, New Zealand Government)
  • Jamie Knight (British Broadcasting Corporation)
  • JaEun Jemma Ku (University of Illinois at Urbana-Champaign)
  • Shane McCarron (Invited Expert, Aptest)
  • Charles McCathie Nevile (Yandex)
  • Mary Jo Mueller (IBM Corporation)
  • James Nurthen (Oracle Corporation)
  • Ian Pouncey (The Paciello Group, LLC)
  • Mark Sadecki (Invited Expert)
  • Janina Sajka (Invited Expert, The Linux Foundation)
  • Joseph Scheuhammer (Invited Expert, Inclusive Design Research Centre, OCAD University)
  • Stefan Schnabel (SAP AG)
  • Richard Schwerdtfeger (IBM Corporation)
  • Lisa Seeman (Invited Expert)
  • Tzviya Siegman (Wiley)
  • Cynthia Shelly (Microsoft Corporation)
  • Alexander Surkov (Mozilla Foundation)
  • Léonie Watson (The Paciello Group)
  • Jason White (Educational Testing Service)
  • Gottfried Zimmermann (Invited Expert, Access Technologies Group)

A.2.2 Other ARIA contributors, commenters, and previously active participants §

  • Shadi Abou-Zahra (W3C)
  • Jim Allan (TSB)
  • Jonny Axelsson (Opera Software)
  • David Baron (Mozilla Foundation)
  • Art Barstow (Nokia Corporation)
  • Simon Bates
  • Chris Blouch (AOL)
  • Judy Brewer (W3C/MIT)
  • Mark Birbeck (Sidewinder Labs)
  • Sally Cain (Royal National Institute of Blind People (RNIB))
  • Gerardo Capiel (Benetech)
  • Ben Caldwell (Trace)
  • Sofia Celic-Li
  • Jaesik Chang (Samsung Electronics Co., Ltd.)
  • Alex Qiang Chen (University of Manchester)
  • Charles Chen (Google, Inc.)
  • Christian Cohrs
  • Deborah Dahl
  • Erik Dahlström (Opera Software)
  • Dimitar Denev (Frauenhofer Gesellschaft)
  • Micah Dubinko (Invited Expert)
  • Mandana Eibegger
  • Beth Epperson (Websense)
  • Donald Evans (AOL)
  • Chris Fleizach (Apple Inc.)
  • Kelly Ford (Microsoft Corporation)
  • Geoff Freed (Invited Expert, NCAM)
  • Christopher Gallelo (Microsoft Corporation)
  • Birkir Gunnarsson (Deque Systems, Inc.)
  • Kentarou Fukuda (IBM Corporation)
  • Bryan Garaventa
  • Guido Geloso
  • Ali Ghassemi
  • Becky Gibson (IBM)
  • Alfred S. Gilman
  • Andres Gonzalez (Adobe Systems Inc.)
  • Scott González (JQuery Foundation)
  • James Graham
  • Georgios Grigoriadis (SAP AG)
  • Jeff Grimes (Oracle)
  • Loretta Guarino Reid (Google, Inc.)
  • Barbara Hartel
  • James Hawkins (Google, Inc.)
  • Benjamin Hawkes-Lewis
  • Sean Hayes (Microsoft Corporation)
  • Mona Heath (University of Illinois at Urbana-Champaign)
  • Jan Heck
  • Shawn Henry
  • Tina Homboe
  • John Hrvatin (Microsoft Corporation)
  • Takahiro Inada
  • Masayasu Ishikawa (W3C)
  • Jim Jewitt
  • Kenny Johar (Microsoft Corporation)
  • Shilpi Kapoor (BarrierBreak Technologies)
  • Masahiko Kaneko (Microsoft Corporation)
  • Marjolein Katsma
  • George Kerscher (International Digital Publishing Forum)
  • Jason Kiss (New Zealand Government)
  • Todd Kloots
  • Johannes Koch
  • Sam Kuper
  • Earl Johnson (Sun)
  • Jael Kurz
  • Rajesh Lal (Nokia Corporation)
  • Diego La Monica (International Webmasters Association / HTML Writers Guild (IWA-HWG))
  • Aaron Leventhal (IBM Corporation)
  • Gez Lemon (International Webmasters Association / HTML Writers Guild (IWA-HWG))
  • Alex Li (SAP)
  • Chris Lilley
  • Thomas Logan (HiSoftware Inc.)
  • William Loughborough (Invited Expert)
  • Linda Mao (Microsoft)
  • David MacDonald (Invited Expert, CanAdapt Solutions Inc.)
  • Carolyn MacLeod
  • Anders Markussen (Opera Software)
  • Krzysztof Maczyński
  • Matthew May (Adobe Systems Inc.)
  • Dominic Mazzoni (Google, Inc.)
  • Alexandre Morgaut (4D)
  • Ann Navarro (Invited Expert)
  • Joshue O Connor (Invited Expert, CFIT)
  • Artur Ortega (Microsoft Corporation)
  • Sailesh Panchang (Deque)
  • Lisa Pappas (Society for Technical Communication (STC))
  • Marta Pawlowlska (Samsung Electronics Co., Ltd.)
  • Dave Pawson (RNIB)
  • Steven Pemberton (CWI Amsterdam)
  • Simon Pieters (Opera Software)
  • Jean-Bernard Piot (4D)
  • David Poehlman, Simon Pieters (Opera Software)
  • Sarah Pulis (Media Access Australia)
  • T.V. Raman (Google, Inc.)
  • Jan Richards
  • Gregory Rosmaita (Invited Expert)
  • Tony Ross (Microsoft Corporation)
  • Alex Russell (Dojo Foundation) (
  • Mark Sadecki (Invited Expert)
  • Mario Sánchez Prada (Samsung Electronics Co., Ltd. and Gnome Foundation)
  • Martin Schaus (SAP AG)
  • Doug Schepers (W3C)
  • Matthias Schmitt
  • Marc Silbey (Microsoft Corporation)
  • Leif Halvard Sili
  • Henri Sivonen (Mozilla)
  • Michael Smith (W3C)
  • Andi Snow-Weaver (IBM Corporation)
  • Ville Skyttä
  • Henny Swan (BBC)
  • Neil Soiffer (Design Science)
  • Vitaly Sourikov
  • Mike Squillace (IBM)
  • Maciej Stachowiak (Apple Inc.)
  • Christophe Strobbe
  • Suzanne Taylor (Pearson plc)
  • Terrill Thompson
  • David Todd
  • Gregg Vanderheiden (Invited Expert, Trace)
  • Anne van Kesteren
  • Wen He (Tencent)
  • Wu Wei (W3C / RITT)
  • Ryan Williams (Oracle)
  • Tom Wlodkowski
  • Sam White (Apple Inc.)
  • Marco Zehe (Mozilla Foundation)

A.2.3 Enabling funders §

This publication has been funded in part with U.S. Federal funds from the Department of Education, National Institute on Disability, Independent Living, and Rehabilitation Research (NIDILRR), initially under contract number ED-OSE-10-C-0067 and currently under contract number HHSP23301500054C. The content of this publication does not necessarily reflect the views or policies of the U.S. Department of Education, nor does mention of trade names, commercial products, or organizations imply endorsement by the U.S. Government.

B. References §

B.1 Normative references §

[CORE-AAM]
Joseph Scheuhammer; Michael Cooper; Andi Snow-Weaver; Aaron Leventhal et al. W3C. Core Accessibility API Mappings 1.1. W3C Working Draft. URL: https://www.w3.org/TR/core-aam-1.1/
[GRAPHICS-AAM]
Amelia Bellamy-Royds; Fred Esch; Richard Schwerdtfeger et al. W3C. Graphics Accessibility API Mappings. W3C Working Draft. URL: https://www.w3.org/TR/graphics-aam-1.0/
[GRAPHICS-ARIA]
Amelia Bellamy-Royds; Fred Esch; Rich Schwerdtfeger; Leonie Watson et al. W3C. WAI-ARIA Graphics. W3C Working Draft. URL: https://www.w3.org/TR/graphics-aria-1.0/
[HTML5]
Ian Hickson; Robin Berjon; Steve Faulkner; Travis Leithead; Erika Doyle Navara; Edward O'Connor; Silvia Pfeiffer. W3C. HTML5. 28 October 2014. W3C Recommendation. URL: https://www.w3.org/TR/html5/
[RFC2119]
S. Bradner. IETF. Key words for use in RFCs to Indicate Requirement Levels. March 1997. Best Current Practice. URL: https://tools.ietf.org/html/rfc2119
[SVG]
Jon Ferraiolo. W3C. Scalable Vector Graphics (SVG) 1.0 Specification. 4 September 2001. W3C Recommendation. URL: https://www.w3.org/TR/SVG/

B.2 Informative references §

[ACCNAME-AAM]
Joseph Scheuhammer; Michael Cooper; Andi Snow-Weaver; Aaron Leventhal et al. W3C. Accessible Name and Description: Computation and API Mappings 1.1. W3C Working Draft. URL: https://www.w3.org/TR/accname-aam-1.1/
[ARIA-PRACTICES]
Matt King; James Nurthen; Michael Cooper; Michiel Bijl; Joseph Scheuhammer; Lisa Pappas; Richard Schwerdtfeger et al. W3C. WAI-ARIA Authoring Practicess 1.1. W3C Working Draft. URL: https://www.w3.org/TR/wai-aria-practices-1.1/
[AT-SPI]
The GNOME Project. Assistive Technology Service Provider Interface. URL: https://developer.gnome.org/libatspi/stable/
[ATK]
The GNOME Project. ATK - Accessibility Toolkit. URL: https://developer.gnome.org/atk/stable/
[AXAPI]
Apple Corporation. The Mac OS X Accessibility Protocol Mac OS 10.10. URL: https://developer.apple.com/library/mac/documentation/Cocoa/Reference/ApplicationKit/Protocols/NSAccessibility_Protocol/index.html
[IAccessible2]
Linux Foundation. IAccessible2. URL: http://www.linuxfoundation.org/collaborate/workgroups/accessibility/iaccessible2
[MSAA]
Microsoft Corporation. Microsoft Active Accessibility (MSAA) 2.0. URL: https://msdn.microsoft.com/en-us/library/ms697707.aspx
[SVG-AAM]
Amelia Bellamy-Royds; Richard Schwerdtfeger et al. W3C. SVG2 Accessibility API Mappings 1.0. W3C Working Draft. URL: https://www.w3.org/TR/svg-aam-1.0/
[UI-AUTOMATION]
Microsoft Corporation. UI Automation. URL: https://msdn.microsoft.com/en-us/library/ee684009%28v=vs.85%29.aspx
[UIA-EXPRESS]
Microsoft Corporation. The IAccessibleEx Interface. URL: https://msdn.microsoft.com/en-us/library/windows/desktop/dd561898%28v=vs.85%29.aspx
[WAI-ARIA]
James Craig; Michael Cooper; Shane McCarron et al. W3C. Accessible Rich Internet Applications (WAI-ARIA) 1.1. W3C Working Draft. URL: https://www.w3.org/TR/wai-aria-1.1/
[WAI-ARIA-10]
James Craig; Michael Cooper et al. W3C. Accessible Rich Internet Applications (WAI-ARIA) 1.0. W3C Recommendation. URL: https://www.w3.org/TR/wai-aria/
[WAI-ARIA-IMPLEMENTATION]
Joseph Scheuhammer; Michael Cooper. W3C. WAI-ARIA 1.0 User Agent Implementation Guide. 20 March 2014. W3C Recommendation. URL: https://www.w3.org/TR/wai-aria-implementation/
[WAI-ARIA-PRACTICES]
Joseph Scheuhammer; Michael Cooper. W3C. WAI-ARIA 1.0 Authoring Practices. 14 July 2016. W3C Working Draft. URL: https://www.w3.org/TR/wai-aria-practices/
[WCAG20]
Ben Caldwell; Michael Cooper; Loretta Guarino Reid; Gregg Vanderheiden et al. W3C. Web Content Accessibility Guidelines (WCAG) 2.0. 11 December 2008. W3C Recommendation. URL: https://www.w3.org/TR/WCAG20/