The Graphics Accessibility API Mappings defines how user agents map the WAI-ARIA Graphics Module [[!GRAPHICS-ARIA-1.0]] 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 [[HTML52]].
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-1.0]].
The Graphics Accessibility API Mappings is part of the WAI-ARIA suite described in the WAI-ARIA Overview.
This is an Editor's 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-1.0]] to accessibility APIs, and complements SVG-specific mappings in the SVG Accessibility API Mappings [[SVG-AAM-1.0]]. It extends Core Accessibility Mappings 1.1 [[!CORE-AAM-1.1]], 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.
The Graphics Accessibility API Mappings specification provides role mappings for the roles in the WAI-ARIA Graphics Module [[!GRAPHICS-ARIA-1.0]].
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:
The main content of this specification is normative and defines requirements that impact conformance claims. Introductory material, appendices, sections marked as "non-normative" and their subsections, diagrams, examples, and notes are informative (non-normative). Non-normative material provides advisory information to help interpret the guidelines but does not create requirements that impact a conformance claim.
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 an 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.
Normative sections provide requirements that authors, user agents and assistive technologies MUST follow for an implementation to conform to this specification.
Non-normative (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.
This section MUST conform to General rules for exposing WAI-ARIA semantics in [[!CORE-AAM-1.1]].
User agents MUST conform to Conflicts between native markup semantics and WAI-ARIA in [[!CORE-AAM-1.1]].
User agents MUST conform to Exposing attributes that do not directly map to accessibility API properties in [[!CORE-AAM-1.1]].
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.
User agents MUST conform to the Role Mapping General Rules accessibility API computational requirements in [[!CORE-AAM-1.1]].
This section defines how roles in graphics 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.
| WAI-ARIA Role | MSAA + IAccessible2 Role + Other IAccessible2 Features | UIA Control Type + Other Features | ATK/AT-SPI Role | AXAPI |
|---|---|---|---|---|
graphics-document |
IAccessible2: Object attribute |
Control Type: 'Document'. |
Expose |
AXRole: AXGroupAXSubrole: AXDocumentAXRoleDescription: 'document'
|
graphics-object |
ROLE_SYSTEM_GROUPING + IAccessible2: Object attribute |
Control Type: 'Group'. |
Expose |
AXRole: AXGroupAXSubrole: <nil>AXRoleDescription: 'group'
|
graphics-symbol |
ROLE_SYSTEM_GRAPHICIAccessible2: Object attribute |
Control Type: 'Image'. |
Expose |
AXRole: AXImageAXSubrole: <nil>AXRoleDescription: 'image'
|
The full commit history to Graphics Accessibility API Mappings 1.0 is available.
The following people contributed to the development of this document.
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.