This document provides information to authoring tool developers who wish to
satisfy the checkpoints of "Authoring Tool Accessibility Guidelines 1.0" [ATAG10]. It includes
suggested techniques, sample strategies in deployed tools, and references to
other accessibility resources (such as platform-specific software
accessibility guidelines) that provide additional information on how a tool
may satisfy each checkpoint.
This document is part of a series of accessibility documents published by
the W3C Web Accessibility Initiative
(WAI).
This section describes the status of this document at the time of its
publication. Other documents may supersede this document. The latest status of
this document series is maintained at the W3C.
This document is a draft update to a W3C Note, published as an informative
appendix to "Authoring Tool Accessibility Guidelines 1.0". The Working Group
expects to update this document in response to queries raised by implementors
of the Guidelines, for example, to cover new technologies. Suggestions for
additional techniques are welcome.
The "Authoring Tool Accessibility Guidelines 1.0" [ATAG10] has two goals: to assist
developers in designing authoring tools that produce accessible Web content
and to assist developers in creating an accessible authoring interface. The
present "Techniques Document" suggests to developers some strategies for
meeting those goals.
Implementation of techniques for some of these guidelines requires
familiarity with the Web Content Accessibility Guidelines (WCAG)
1.0 [WCAG10]. In
addition, readers are strongly encouraged to become familiar with the
"Techniques for Web Content Accessibility Guidelines 1.0" [WCAG10-TECHS] and "Techniques for User Agent Accessibility
Guidelines 1.0" [UAAG10-TECHS].
Note: The techniques in this document are merely
suggestions; they are not required for conformance to "Authoring Tool
Accessibility Guidelines 1.0". These techniques are not necessarily the only
way of satisfying the checkpoint, nor are they necessarily a definitive set of
requirements for satisfying a checkpoint.
This document has the same structure as the "Authoring Tool Accessibility
Guidelines 1.0" [ATAG10]: seven guidelines, each of which includes at least one
checkpoint. Information about checkpoint priorities is
found in the "Authoring Tool Accessibility Guidelines 1.0".
Unlike "Authoring Tool Accessibility Guidelines 1.0", the current document
includes a list of techniques after each checkpoint. Techniques may be
suggested strategies, references to other accessibility resources (noted
"Reference"), or examples of how deployed tools satisfy the checkpoint (noted
"Sample").
For some guidelines there are techniques or information that are relevant
to the entire guideline. These are provided at the end of the section for the
relevant guideline.
Some of the sample techniques describe how Amaya satisfies the checkpoints.
Amaya [AMAYA] is both
an HTML authoring tool and a browser. Amaya's default editing view is WYSIWYG-style. The Amaya
techniques are also available as a single "sample implementation" document
[AMAYA-SAMPLE].
If the tool automatically generates markup, many authors will be unaware of
the accessibility status of the final content unless they expend extra effort
to review it and make appropriate corrections by hand. Since many authors are
unfamiliar with accessibility, authoring tools are responsible for
automatically generating accessible markup, and where appropriate, for guiding
the author in producing accessible content.
Many applications feature the ability to convert
documents from other formats (e.g., Rich Text Format) into a markup
format specifically intended for the Web such as HTML. Markup changes may also
be made to facilitate efficient editing and manipulation. It is essential that
these processes do not introduce inaccessible markup or remove accessibility
content, particularly when a tool hides the markup changes from the author's
view.
Most image formats, including PNG, SVG, WebCGM, JPEG, and GIF
allow the inclusion of text content. Where it is available in the
format, this feature should be used by authoring tools.
Many formats for audio or video allow authors to include
equivalent alternatives.
An audio/video editing suite can use SMIL to synchronize audio,
video, descriptive signing and text tracks.
Reference: Web Content Accessibility Guidelines 1.0 [WCAG10] and
Techniques for Web Content Accessibility Guidelines 1.0 [WCAG10-TECHS]
Reference: The Web Accessibility Initiative has published a
number of documents on the accessibility features of different W3C
specifications:
Accessibility of Scalable Vector Graphics [SVG-ACCESS]
In each case the specifications themselves also provide
information.
Sample: Amaya implements all of the accessibility features
of HTML. The CSS cascade order, an accessibility feature of CSS2,
has not yet been completely implemented in Amaya.
When transforming a table to a list or list of lists, ensure that
table headings are transformed into headings and that summary or
caption information is retained as rendered content. This
transformation may not be reversible.
Even when a document's graphical layout has been rearranged,
ensure that the document makes sense when rendered serially. For
example, prompt the author to confirm linearized reading order after
the graphical layout has changed. Desktop publishing software often
has such a feature.
When importing images with associated descriptions to an HTML
document make the descriptions available through appropriate markup.
For instance, in HTML use "longdesc" or
"alt".
When converting from a word-processor format to HTML, ensure that
headings and list items are transformed into appropriate headings of
the appropriate level, and list items in the appropriate type of
list (rather than as plain text with font formatting)
Do not transform text into images - use style sheets for
presentation control, or an XML application such as Scalable Vector
Graphics [SVG]
that keeps the text as text. If this is not possible, ensure that
the text that is converted is available as equivalent text for the
image.
Ensure that the tool recognizes and preserves elements that are
defined in the relevant specification(s) even if it is unable to
render them in a publishing view or preview mode. This is relevant
for WYSIWYG page authoring tools, tools that handle image
formats which allow the incorporation of equivalent text or data,
and tools for multimedia and data-processing.
When converting linked elements such as footnotes or endnotes
either provide them as inline content or maintain two-way linking.
In HTML, this should be hypertext links rather than plain-text
references.
Sample: The predefined transformations shipped with Amaya
preserve all element content. The transformation language allows the
preservation of attribute values, but this is not done by all the
supplied transformations.
1.3 Ensure that when the tool
automatically generates markup it conforms to the W3C's Web Content Accessibility Guidelines 1.0
[WCAG10]. [Relative Priority] (Checkpoint
1.3)
Use consistent document structures. For a tool that does site-wide
management, provide consistent navigation systems and document
structures.
Include markup that provides equivalent alternatives for
media-dependent elements or content.
Do not use structural markup for presentation
effects, or presentation markup for known
structures. For example, use list markup of an appropriate type
rather than creating multiple line paragraphs and beginning each
line with an image of a bullet. Do not use list markup for an
indentation effect.
Do not publish Web content in markup languages that do not allow
for equivalent alternative information to be included for
media-specific presentations (such as images or video, sound,
etc).
New markup languages are constantly being developed, and in many
cases offer improvements to the structure and utility of Web
content. In implementing a new or extended markup language, it is
important to ensure that a tool does not remove access to
information that had been inherent in the base markup language.
The same can apply to a format that simplifies an existing
format. For example, producing a modified HTML DTD that did not
include the "alt" attribute for the IMG
element, or effectively working to such a DTD by not implementing a
means to include the attribute, compromises the accessibility of any
included IMG elements.
Reference: The Web Accessibility Initiative's Protocols and
Formats group have a draft set of notes about creating accessible
markup languages [XMLGL].
Sample: Amaya generates markup that conforms to level-A,
and allows the author to generate markup that is triple-A through
the user interface.
1.4 Ensure that templates
provided by the tool conform to the Web Content Accessibility Guidelines 1.0
[WCAG10]. [Relative Priority] (Checkpoint
1.4)
Produce accessible representations for site maps generated by the
authoring tool.
Provide equivalent alternatives for all non-text content (images,
audio, etc).
Use consistent navigation mechanisms.
Ensure that event-handlers for scripts are
device-independent.
Ensure that color schemes provide sufficient contrast for people
or technology with poor color separation.
Ensure that the natural language of the template is
identified.
Provide navigation bars.
Provide keyboard shortcuts for important links, etc.
Sample: Amaya has templates, which have not yet been
checked for conformance to WCAG 1.0 [WCAG10].
Some sample templates are available: (Note that these samples are
still subject to review, and may require changes.
Conformance with standards promotes interoperability and accessibility by
making it easier to create specialized user agents that address the needs of users
with disabilities. In particular, many assistive technologies used with
browsers and multimedia players are only able to provide access to Web documents that use valid markup. Therefore,
valid markup is an essential aspect of authoring tool accessibility.
Where applicable use W3C
Recommendations, which have been reviewed to ensure accessibility and
interoperability. If there are no applicable W3C Recommendations, use a published standard that enables
accessibility.
Checkpoints:
2.1 Use the latest versions of W3C Recommendations when they
are available and appropriate for a task. [Priority 2] (Checkpoint
2.1)
W3C specifications have undergone review specifically to ensure that
they do not compromise accessibility, and where possible, they enhance
it.
When creating documents or markup languages, make full use of W3C Recommendations. For example, when
creating mathematical content for the Web use MathML [MATHML]
rather than another markup language. Use applicable HTML 4 [HTML4]
structures.
Specifications that become W3C Recommendations after an authoring
tool's development cycles permit input are not considered
"available" in time.
Ensure that the tool recognizes and preserves elements that are
defined in the relevant specification(s) even if it is unable to
render them. This is particularly important for WYSIWYG editing tools.
Sample: Amaya supports HTML 4 [HTML4], XHTML 1.0 [XHTML10], and most of CSS1 [CSS1]. It provides partial
support for MathML [MATHML] and some experimental support for Scalable
Vector Graphics [SVG].
2.2 Ensure that the tool
automatically generates valid markup. [Priority 1] (Checkpoint
2.2)
This is necessary for user
agents to be able to render Web content in a manner
appropriate to a particular user's needs.
A tool that provides a Web editing mode and a non-Web editing mode
can change modes when invalid markup is introduced. Refer also to
checkpoint 4.1.
Sample: If Amaya imports or generates markup that does not
conform to W3C specifications it is highlighted in the structure
view. This occurs when Amaya tries to repair invalid markup and
cannot successfully do so.
Well-structured information and equivalent alternative information are
cornerstones of accessible design, allowing information to be presented in a
way most appropriate for the needs of the user without constraining the
creativity of the author. Yet producing equivalent information, such as text
alternatives for images and auditory descriptions of video, can be one of the
most challenging aspects of Web design, and authoring tool developers should
attempt to facilitate and automate the mechanics of this process. For example,
prompting authors to include equivalent alternative information such as text equivalents, captions, and auditory descriptions at appropriate times can
greatly ease the burden for authors. Where such information can be
mechanically determined and offered as a choice for the author (e.g., the
function of icons in an automatically-generated navigation bar, or expansion
of acronyms from a dictionary), the tool can assist the author. At the same
time, the tool can reinforce the need for such information and the author's
role in ensuring that it is used appropriately in each instance.
Note: Some checkpoints in the Web Content
Accessibility Guidelines 1.0 [WCAG10] may not apply.
When a multimedia object is inserted, prompt the author for
relevant alternatives: functional replacement and long description
for images, text captions (as text or as a URI), video of signed
translations for audio, and audio descriptions for video (as well as
alternatives for its audio components).
Provide an author with the option of specifying alternative
information, or electing to insert null alternative information for
images, audio, video. Default to an accessibility error such as no
TITLE or DESC element for SVG images.
Prompt the author to identify the type of image (decorative, a
navigation icon, etc.).
When video is inserted, prompt the author for a still image as
part of the alternative information.
When inserting objects such as spreadsheets or word processor
documents, offer the option of providing a Web-formated version. For
example, a spreadsheet or a word processor document in a proprietary
format could also be published as an HTML document. Tools that
dynamically generate Web content may use HTTP content negotiation to
facilitate this.
Use the same User interface for server and client side
image map creations, including prompting for alternatives
for each region. Use alternatives provided to generate
redundant text-based links for server-side maps.
Prompt for text which describes the range and the effect
of possible coordinate entries, and generate an
alternative, form-based entry system.
1.3Until user
agents can automatically read aloud the text equivalent of a
visual track, provide an auditory description of the important
information of the visual track of a multimedia presentation.
[Priority 1]
Prompt the author to provide an audio track that
includes description, if necessary with an
alternative version of the video.
1.4 For any
time-based multimedia presentation (e.g., a movie or animation),
synchronize equivalent alternatives (e.g., captions or auditory
descriptions of the visual track) with the presentation. [Priority 1]
Use a format such as SMIL which allows for the
inclusion and synchronization of equivalent
tracks
XML
Use SMIL timing to synchronize equivalents
1.5Until user
agents render text equivalents for client-side image map
links, provide redundant text links for each active region of a
client-side image map. [Priority 3]
2.2 Ensure that foreground
and background color combinations provide sufficient contrast when
viewed by someone having color deficits or when viewed on a black
and white screen. [Priority 2 for images, Priority 3 for
text].
Where only one color has been specified (for example a
background but not foreground) ask the author to specify
(or confirm default) colors for other parts, where
possible from a range that has sufficient contrast.
3.1 When an appropriate markup
language exists, use markup rather than images to convey
information. [Priority 2]
Where scripts change the src attribute of images,
prompt the author to include changes in the alt
attribute or element content.
SVG, XHTML
Where SMIL animation is used, prompt the author to
ensure that desc and
title elements are appropriately
updated by the animation
6.3
Ensure that pages are usable when scripts, applets, or other
programmatic objects are turned off or not supported. If this is
not possible, provide equivalent information on an alternative
accessible page. [Priority 1]
7.1Until user agents allow users to
control flickering, avoid causing the screen to flicker. [Priority 1]
Note. People with photosensitive epilepsy
can have seizures triggered by flickering or flashing in the 4
to 59 flashes per second (Hertz) range with a peak sensitivity
at 20 flashes per second as well as quick changes from dark to
light (like strobe lights).
HTML (relying on lowsrc attribute - not in W3C
recommendation)
Prompt for a non-animated "lowsrc" version of animated
images.
7.2Until user agents allow users to
control blinking, avoid causing content to blink (i.e., change
presentation at a regular rate, such as turning on and off). [Priority 2]
7.3Until user agents allow users to
freeze moving content, avoid movement in pages. [Priority 2]
When a page includes moving content, provide a mechanism
within a script or applet to allow users to freeze motion or
updates. Using style sheets with scripting to create movement
allows users to turn off or override the effect more easily.
Refer also to WCAG
guideline 8.
8.1 Make programmatic
elements such as scripts and applets directly accessible or
compatible with assistive technologies [Priority 1 if functionality is important and not
presented elsewhere, otherwise Priority 2.]
9.1 Provide client-side
image maps instead of server-side image maps except where the
regions cannot be defined with an available geometric shape. [Priority 1]
11.4 If, after best
efforts, you cannot create an accessible page, provide a link to
an alternative page that uses W3C technologies, is accessible, has
equivalent information (or
functionality), and is updated as often as the inaccessible
(original) page. [Priority 1]
Metadata can be added to most image formats commonly
used on the Web, including PNG, JPEG, GIF, and SVG.
@@Include link to rdfpic sample tool that does this
(source available too).
14.2
Supplement text with graphic or auditory presentations where they
will facilitate comprehension of the page. [Priority 3]
Provide libraries of accessible clip art to illustrate
common concepts, or allow the author to build them. See
also ATAG 3.5
3.2 Help the author create
structured content and separate information from its presentation. [Relative Priority] (Checkpoint
3.2)
Note: Some checkpoints in Web
Content Accessibility Guidelines 1.0 [WCAG10] may not apply.
Recognize collections of uppercase letters as likely abbreviations
(in languages that have case) and prompt the author for an
expansion, to be provided in markup (e.g., in HTML, with
ABBR or ACRONYM).
Prompt the author to identify the structural role of content that
has been emphasized through styling.
In Japanese, Chinese, and other appropriate languages, prompt the
author for text that can be used as a ruby for unusual ideographs or
ideographic groups. Refer to [RUBY].
Prompt the author for header information for tabular data.
Prompt the author (and allow them to specify a default suggestion)
for the language of a document.
Sample: In future releases Amaya is expected to prompt the
author for "title" for ABBR,
ACRONYM, OBJECT, and IMG
elements, and LABEL for FORM controls.
The user interface of Amaya was developed to guide authors to
produce structured documents. Style in Amaya is created as a
stylesheet.
Techniques for different languages, organized by Web Content
Accessibility Guidelines checkpoints:
1.1 Provide a text
equivalent for every non-text element
[Priority 1]
Ask the author to identify regions in an image map, or
to describe how the coordinates will be used so that a
form-based input method can be generated.
1.3Until user
agents can automatically read aloud the text equivalent of a
visual track, provide an auditory description of the important
information of the visual track of a multimedia presentation.
[Priority 1]
1.4 For any
time-based multimedia presentation (e.g., a movie or animation),
synchronize equivalent alternatives (e.g., captions or auditory
descriptions of the visual track) with the presentation. [Priority 1]
1.5Until user
agents render text equivalents for client-side image map
links, provide redundant text links for each active region of a
client-side image map. [Priority 3]
Prompt the author to identify a class, or markup
element for uses of color.
2.2 Ensure that foreground
and background color combinations provide sufficient contrast when
viewed by someone having color deficits or when viewed on a black
and white screen. [Priority 2 for images, Priority 3 for
text].
5.2 For data tables that
have two or more logical levels of row or column headers, use
markup to associate data cells and header cells. [Priority 1]
For example, in HTML, use THEAD, TFOOT, and TBODY to group
rows, COL and COLGROUP to group columns, and the "axis",
"scope", and "headers" attributes, to describe more complex
relationships among data.
Ask the author to group columns, rows, or blocks of
cells that are related.
5.3 Do not use
tables for layout unless the table makes sense when linearized.
Otherwise, if the table does not make sense, provide an
alternative equivalent (which may be a linearized version). [Priority 2]
Prompt the author to identify tables which are
used as layout devices.
For layout tables, provide a linearized version,
and offer it as a link from the table or as a
replacement. An example tool which linearizes tables
is tablin.
5.4 If a table is used for
layout, do not use any structural markup for the purpose of visual
formatting. [Priority 2]
In a table creation wizard, include a summary or
caption dialog
Render the caption,
title and summary of a
table, or prompt for content.
Amaya's user interface guides the author to include
a caption for tables,in the following way: When the
author creates a table, a dialog is generated which
asks for number of rows, columns, border width
The author selects the appropriate information and a
table is created. The cursor is placed at the
position of the table caption. The status line,
which appears at the bottom of the image, shows that
the position is in the caption element of the table.
(This is a standard part of the Amaya user
interface).
5.6 Provide abbreviations
for header labels.
[Priority 3]
Prompt for an abbreviated form of each table header
(th)
6.1 Organize documents
so they may be read without style sheets. For example, when an
HTML document is rendered without associated style sheets, it must
still be possible to read the document.
[Priority 1]
Prompt for appropriate changes to title
and desc elements which are children of the
target of an animate.
HTML
See also frames.
6.3 Ensure that pages are usable
when scripts, applets, or other programmatic objects are turned
off or not supported. If this is not possible, provide equivalent
information on an alternative accessible page. [Priority 1]
7.2Until user agents allow users to
control blinking, avoid causing content to blink (i.e., change
presentation at a regular rate, such as turning on and off). [Priority 2]
7.5Until user agents provide the
ability to stop auto-redirect, do not use markup to redirect pages
automatically. Instead, configure the server to perform redirects.
[Priority 2]
8.1 Make programmatic
elements such as scripts and applets directly accessible or
compatible with assistive technologies [Priority 1 if functionality is important and not
presented elsewhere, otherwise Priority 2.]
9.1 Provide client-side
image maps instead of server-side image maps except where the
regions cannot be defined with an available geometric shape. [Priority 1]
where regions are not easily defined, ask the author
to provide information that can be used to generate a
form-based input method and explains how the coordinates
input will be used. For example, on a map the input
might be used to lookup latitude and longitude of a
point and then give information about that point.
9.2 Ensure that any
element that has its own interface can be operated in a
device-independent manner.
[Priority 2]
Where there are only a few links that change in each
page of a collection, ask the author if they should
receive focus first. If so, then give them a tabindex,
leaving the rest to after the tabindexed links have been
focussed.
9.5 Provide keyboard
shortcuts to important links (including those in client-side
image maps), form controls, and groups of form
controls. [Priority 3]
Ask authors to specify an accesskey for links that
appear common to a number of pages
10.1Until user agents allow users to
turn off spawned windows, do not cause pop-ups or other windows to
appear and do not change the current window without informing the
user. [Priority 2]
Where a link or active element will spawn a new
window, prompt the author for title text to
make this clear.
10.2Until user agents support explicit
associations between labels and form controls, for all form
controls with implicitly associated labels, ensure that the label
is properly positioned. [Priority 2]
11.4 If, after best
efforts, you cannot create an accessible page, provide a link to
an alternative page that uses W3C technologies, is accessible, has
equivalent information (or
functionality), and is updated as often as the inaccessible
(original) page. [Priority 1]
Prompt the author for a short, human-readable
title for each frame. Default text presented in the
prompt could use the title defined for
the document referenced in the src
12.2 Describe the purpose of
frames and how frames relate to each other if it is not obvious by
frame titles alone.
[Priority 2]
Prompt the author for a longdesc for
each frame in a frameset.
Prompt the author to add a noframes
section to the frameset. Encourage the author to
include sufficient links to navigate the site, and
relevant information. For example, where a frameset
defines a navigation frame and a welcome page,
include the content of each of these frames in the
noframes.
12.3 Divide large blocks
of information into more manageable groups where natural and
appropriate. [Priority 2]
Use formats that allow for accessible annotation to be included in
the files, such as SMIL, PNG, and SVG.
Provide long descriptions, and associated text files with
appropriate text
equivalent in clip-art collections.
Provide video description files with prepackaged video.
Provide text caption files for prepackaged audio, or video with
auditory track(s).
Including pre-written descriptions for all multimedia files (e.g.,
clip-art) packaged with the tool will save authors time and effort,
cause a significant number of professionally written descriptions to
circulate on the Web, provide authors with convenient models to
emulate when they write their own descriptions, and show authors the
importance of description writing.
Sample: Amaya does not provide any clip art or other
prepackaged content.
3.4 Do not automatically generate equivalent alternatives. Do not reuse
previously authored alternatives without author confirmation, except when
the function is known with certainty.
[Priority 1] (Checkpoint
3.4)
For example, prompt the author for a text equivalent of an
image. If the author has already provided a text equivalent for the same
image used in another document, offer to reuse that text and prompt the
author for confirmation. If the tool automatically generates a "Search"
icon, it would be appropriate to automatically reuse the previously
authored text equivalent for that icon. Refer also to checkpoint 3.3 and
checkpoint 3.5.
Note: Human-authored equivalent alternatives may be
available for an object (for example, through checkpoint 3.5 and/or
checkpoint 3.3).
It is appropriate for the tool to offer these to the author as
defaults.
Items used throughout a Website, such as graphical navigation
bars, should have standard alternative information. However the
author should be prompted to edit or approve this the first time it
is used in a site, and when the destination of the links is changed
by the author.
If the author has not specified alternative text for an
IMG, or specified that none is required, default to
having no "alt" attribute, so that an accessibility
problem will be noted. Refer also to checkpoint 4.1.
Where an object has already been used in a document, the tool
should offer the alternative content that was supplied for the first
or most recent use as a default.
Sample: Amaya does not provide default "alt"
text except when copying and pasting images, in which case it copies
all attributes with the image.
Note: These alternative equivalents may be packaged
with the tool, written by the author, retrieved from the Web, etc.
Maintain a database registry that associates object identity
information with alternative information. Whenever an object is used
and an equivalent alternative is provided, ask the author whether
they want to add the object (or identifying information) and the
alternative information to the database. In the case of a text equivalent,
the alternate information may be stored in the document source. For
more substantial information (such as video captions or audio
descriptions), the information may be stored externally and linked
from the document source. Allow different alternative information to
be associated with a single object.
Suggest pre-written descriptions as default text whenever one of
the associated files is inserted into the author's document.
The use of the Resource Description Framework (RDF)
[RDF10], or
formats like SVG can enable a tool to maintain and use libraries of
information within the tool and on the Web.
This checkpoint is priority 3, meaning that in itself, it does not
have a critical effect on an authoring tool's likelihood of
producing accessible mark-up. However, certain implementations of
this Alternative Information Management Mechanism (AIMM) [APROMPT] have the potential to
simultaneously satisfy several higher priority checkpoints and
dramatically improve the usability of an access aware authoring
tool. In particular:
The AIMM[APROMPT] should maintain a list of
associations between object file names and authored responses to
prompts for alternative information (per checkpoint
3.1). The alternative information may take the form of short
strings (i.e., "alt"-text) or pointers to descriptive files
(i.e., "longdesc", transcripts, etc.). Multiple associations for
the same object for different languages or contexts should also
be handled.
The AIMM[APROMPT] would offer the associated
alternative information as a default whenever the appropriate
associated object is selected for insertion. If no previous
association is found, the field should be left empty (i.e., no
purely rule-generated alternative information should be used).
Note: The term "default" implies that the
alternative information is offered for the author's approval.
The term does not imply that the default alternative information
is automatically placed without the author's approval. Such
automatic placement may only occur when in situations where the
function of the object is known with certainty, per checkpoint 3.4.
Such a situation might arise in the case of a "navigation bar
builder" that places a navigation bar at the bottom of every
page on a site. In this case, it would be appropriate to use the
same "alt"-text automatically for every instance of a particular
image (with the same target) on every page.
The alternative information mechanism should be closely
integrated with the pre-written alternative information provided
for all packaged multimedia files, per checkpoint
3.3. This would allow the alternative information to be
automatically retrieved whenever the author selected one of the
packaged objects for insertion. An important benefit of the
system would be the ease of adding a keyword search capability
that would allow efficient location of multimedia based on its
alternative information.
Sample: Amaya has no registry of alternate text associated
with images, although when an image is copied and pasted its alt and
other attributes are copied too.
Techniques for this guideline:
Techniques for adding alternative content, organized according to the
type of alternative:
The tool may prompt the author to enter a short (10 word or less)
description whenever an element that requires one is added or
edited.
Emphasize that the description alone should provide reader with
sufficient information to make sense of the image.
Provide a link to several high quality described objects in the help
(ATAG Checkpoint 6.1).
Advanced:
The object name is not necessarily a good indication of its content
and so should not be used as a default text in the prompting field
(ATAG Checkpoint 3.4).
However, if the tool stores previous descriptive text-object
associations (including developer authored text for clip art) these
can be placed as default in the prompt field (ATAG Checkpoint
3.5).
In cases where the function of an object is known with certainty
(ex. navigation bar), the short descriptive text can copied without
requiring author intervention.
When Amaya adds an image, the ALT text attribute is clearly visible,
and a value must be entered.
Fictional (based on A-Prompt):
In the fictional case, an alt-text registry could suggest text that had
previously been authored for that image. The image itself is displayed to
make the definition writing process more efficient.
The tool may prompt the author to enter a short (10 word or less)
description that emphasizes its FUNCTION (rather than the appearance)
whenever an element that requires one is added or edited.
Emphasize that the functional description alone should provide
reader with sufficient information about the destination
Provide a link to a number of well described linked-objects in the
help (ATAG Checkpoint 6.1). [our example here]
The link destination path is not necessarily a good indication of
its content and so should not be used as a default text in the
prompting field (ATAG Checkpoint 3.4). If the tool stores previous
functional text-object associations these can be placed as default in
the prompt field
Here, the old alt-text is not suggested because the tool has detected
that the image is linked and therefore is a functional rather than
aesthetic element.
Amaya allows the author to enter a longdesc file name.
Fictional (Based on A-Prompt)
A fictional implementation could save multiple descriptions for the
same file (different languages, etc.) and offer them back in the same was
as alt-text was above. Once again the image is displayed to facilitate
accurate description writing.
Many authoring tools allow authors to create documents with little or no
knowledge about the underlying markup. To ensure accessibility, authoring
tools must be designed so that they can (where possible, automatically)
identify inaccessible
markup, and enable its correction even when the markup itself is
hidden from the author.
Authoring tool support for the creation of accessible Web content should
account for different authoring styles. Authors who can configure the tool's
accessibility features to support their regular work patterns are more likely
to accept accessible authoring practices (refer to guideline 5).
For example, some authors may prefer to be alerted to accessibility
problems when they occur, whereas others may prefer to perform a
check at the end of an editing session. This is analogous to programming
environments that allow users to decide whether to check for correct code
during editing or at compilation.
Note: Validation of markup is an essential aspect of
checking the accessibility of content.
Note: Accessibility problems
should be detected automatically where possible. Where this is not
possible, the tool may need to prompt the author to make decisions or
to manually check for certain types of problems.
Reference: The WAI Evaluation and Repair group [WAI-ER] is
developing a document that discusses detailed techniques for testing
content according to the Web Content Accessibility Guidelines. A
draft of that document is available [AUTO-TOOL].
Where the tools cannot test for accessibility errors, provide the
author with the necessary information, wizards, etc. to check for
themselves. Refer
also to checkpoint 5.1.
Include alerts for WCAG 1.0 [WCAG10] Priority 1 checkpoints in the
default configuration.
Provide an editing view that shows equivalent alternatives in the
main content view to make it clear that they are necessary. This
will make it obvious when they are missing.
Provide a preview mode that uses alternative content. Although
this can give authors a clear understanding of some problems very
easily, it should be made clear that there are many ways in which a
page may be presented (aurally, text-only, text with pictures
separately, on a small screen, on a large screen, etc.). A view that
renders the document as it might appear without technologies such as
style sheets and images enabled, or the ability to turn those
features off and on in the editing view, will also give an author
some idea of whether a document's logical order has been correctly
preserved, whether alternative text is appropriate, etc.
Highlight problems detected when documents are opened, when an
editing or insertion action is completed, or while an author is
editing. Using CSS classes to indicate accessibility problems will
enable the author to easily configure the presentation of
errors.
Where there is a change in the writing script used, prompt the
author to identify whether there has been a change in language
Alert authors to accessibility problems when saving.
Accessibility problems can be highlighted using strategies similar
to spell checking within a word processor. Accessibility alerts
within the document can be linked to context sensitive help. Refer also to
checkpoint 4.2..
Allow authors to choose different alert levels based on the
priority of authoring accessibility recommendations.
If interruptive warnings are used, provide a means for the author
to quickly set the warning to non-obtrusive to avoid
frustration.
Reference: There are online tools whose output can be
integrated with the user interface. Other tools are available for
incorporation in existing software, either as licensed products or
in some cases as "open source" solutions. The WAI Evaluation and
Repair group maintains information about available tools
[WAI-ER].
Reference: Refer also to the WAI accessibility references
listed in techniques for Refer also to checkpoint 1.1..
Reference: The Web Accessibility Initiative's Protocols and
Formats group have a draft set of notes about creating accessible
markup languages [XMLGL].
Sample: Amaya currently checks for validity, but the only
warning of invalid markup appears in the structure view. The Amaya
developers are investigating automating an accessibility check and
author notification. Where Amaya detects an error, it identifies and
highlights the incorrect code in the structure view, allowing the
author to delete it.
At a minimum, provide context-sensitive help with
the accessibility checking required by checkpoint 4.1
Reference: The WAI Evaluation and Repair group [WAI-ER] is
developing a document that discusses detailed techniques for
repairing accessibility errors in content according to the Web
Content Accessibility Guidelines. A draft of that document is
available [AUTO-TOOL].
Assist authors in ways that are consistent with the look and feel
of the authoring tool.
Where there are site-wide errors, to make correction more
efficient, allow the author to make site-wide changes or
corrections. For example, this may be appropriate for a common error
in markup, but may not be appropriate in providing a text equivalent
that is appropriate for one use of an image but completely
inappropriate for the other uses of the image on the same site (or
even the same page).
Allow authors to control both the nature and timing of the
correction process.
Provide a mechanism for authors to navigate sequentially among
uncorrected accessibility errors Refer also to checkpoint 7.4..
Sample: Amaya currently does not satisfy this checkpoint.
Amaya uses its own internal representation for the document markup
that is transformed on output. Possible implementation strategy:
Where there are errors in a document Amaya could alert the author
and warn that the document must be changed, and present the
structure view highlighting areas where it has changed the markup,
allowing the author to abort the editing session or save the changed
version under a new name.
4.3 Allow the author to preserve
markup not recognized by the tool. [Priority 2] (Checkpoint
4.3)
Note: The author may have included
or imported markup that enhances accessibility but is not recognized by
the tool.
Provide a summary of all automated structural changes that may
affect accessibility.
Provide options for the author to confirm or override removal of
markup on a change-by-change basis or as a batch process.
If changes to the markup are necessary for the tool to further
process the document (for example, a tool that requires valid markup
when a document is opened), inform the author.
Do not change the DTD without notifying the author.
Sample: Amaya currently does not satisfy this
checkpoint.
4.4 Provide the author with a
summary of the document's accessibility status.
[Priority 3] (Checkpoint
4.4)
Provide a list of all accessibility errors found in a Web
page.
Provide a summary of accessibility problems remaining by type
and/or by number.
Sample: Amaya currently does not satisfy this
checkpoint.
4.5 Allow the author to
transform presentation
markup that is misused to convey structure into structural markup, and to
transform presentation markup used for style into style sheets. [Priority 3] (Checkpoint
4.5)
Some examples of transformations include: HTML table-based layout
into CSS, HTML BR to the P element, HTML
(deprecated) FONT into heuristically or
author-determined structure, Word processor styles to Web styles,
HTML deprecated presentational markup into CSS, XHTML
span into ruby, MathML presentational
markup to semantic markup.
Allow the author to define transformations for imported documents
that have presentation, rather than structural, markup.
Allow the author to create style rules based on the formatting
properties of an element, and then apply the rule to other elements
in the document, to assist conversion of documents to the use of
style sheets
Include pre-written transformations to rationalize multiple
tables, and to transform (deprecated) presentation HTML into style
sheets.
Remember that accessibility information, including attributes or
properties of the elements being transformed, must be preserved -
see checkpoint
1.2
Sample: Amaya provides a language for specifying structure
transformations, and a large number of predefined transformations
are included.
Techniques for this guideline:
Prompts can be used to encourage authors
to provide information needed to make the content accessible (such as
alternative text equivalents). Prompts are simple requests for
information. For example, a text equivalent entry field prominently
displayed in an image insertion dialog would constitute a prompt. Prompts
are relatively unintrusive and address a problem before it arises.
However, once the author has ignored the prompt, its message is
unavailable.
Alerts warn the author that there are
problems that need to be addressed. The art of attracting the author's
attention is a tricky issue. The way authors are alerted, prompted, or
warned can influence their view of the tool and even their opinion of
accessible authoring. Refer also to
guideline 5.
User Configurable Schedule
A user configurable schedule allows the author to determine the
type of prompts and alerts that are used, including when they are
presented. For example, an author may wish to include multiple
images without being prompted for alternative information, and then
provide the alternative information in a batch process, or may wish
to be reminded each time an image is added. If the prompting is done
on a user-configurable schedule, the author will be able to decide.
This technique allows a tool to suit the needs of a wide range of
authors.
Interruptive Alerts
Interruptive alerts are informative messages that interrupt the
editing process for the author. For example, interruptive alerts are
often presented when an author's action could cause a loss of data.
Interruptive alerts allow problems to be brought to the author's
attention immediately. However, authors may resent the constant
delays and forced actions. Many people prefer to finish expressing
an idea before returning to edit its format.
Unintrusive Alerts
Unintrusive alerts are alerts such as icons, underlines, and
gentle sounds that can be presented to the author without
necessitating immediate action. For example, in some word processors
misspelled text is highlighted without forcing the author to make
immediate corrections. These alerts allow authors to continue
editing with the knowledge that problems will be easy to identify at
a later time. However, authors may choose to ignore the alerts
altogether.
When a new feature is added to an existing software tool without proper
integration, the result is often an obvious discontinuity. Differing color
schemes, fonts, interaction styles, and even software stability can be factors
affecting author acceptance of the new feature. In addition, the relative
prominence of different ways to accomplish the same task can influence which
one the author chooses. Therefore, it is important that creating accessible
content be a natural process when using an authoring tool.
Ensure that author can utilize the tool's accessible authoring
features by the same interaction styles used for other features in
the program. For example, if the tool makes use of onscreen symbols
such as underlines or coloration change rather than dialogs for
conveying information, then the same interface techniques should be
used to convey accessibility information.
The same fonts, text sizes, colors, symbols, etc. that
characterize other program features should also characterize those
dealing with accessibility.
Include considerations for accessibility - such as the
"alt" and "longdesc" attributes of the
HTML IMG element - right below the "src"
attribute in a dialogue box, not buried behind an "Advanced..."
button.
Allow efficient and fast access to accessibility-related settings
with as few steps as possible needed to make any changes that will
generate accessible content.
The accessibility features should be designed as integral
components of the authoring tool application, not plug-ins or other
peripheral components that need to be separately obtained,
installed, configured or executed
The default installation of the authoring tool should include all
accessibility features enabled. The author may have the option to
disable these features later on.
A help page that describes how to make an HTML image map should
include adding alternative information for each AREA
element in the MAP as part of the process. Any
examples of code should give either block content with text links,
or AREA elements that all have relevant
"alt" attribute values.
When an author creates an HTML frameset, suggest the links from
the navigation bar (and perhaps the content of the "first page") as
the content for the NOFRAMES element.
Sample: In Amaya some accessibility features are part of
relevant dialogs. Others, such as longdesc and title attributes must
be separately generated by the author. The development team will
integrate these into the relevant dialogues in future releases.
5.2 Ensure that accessible authoring
practices supporting Web Content Accessibility Guidelines 1.0 [WCAG10] Priority 1
checkpoints are among the most obvious and easily initiated by the author.
[Priority 2] (Checkpoint
5.2)
When the author has selected text to format, the use of CSS should
be emphasized rather than the (deprecated) HTML FONT
element.
Highlight the most accessible solutions when presenting choices
for the author.
Providing an editing view that shows equivalent alternatives in
the main content view will make it clear that they are necessary,
and will make it obvious when they are missing.
If there is more than one option for the author, and one option is
more accessible than another, place the more accessible option first
and make it the default. For example, when requesting equivalent
alternatives for an image with the HTML OBJECT element,
offer an unchecked option for a null value (i.e., there is no
content, implying the image has no real function) with the cursor
positioned in the entry field for alternative text (and, if
available, provide the appropriate value from the "Alternative
Information Management Mechanism"; refer to checkpoint 3.5)
rather than offering the filename as a default suggestion, or
selecting the null "alt" value as a default.
Sample: Amaya's user interface guides the author to produce
structured content, with presentation elements separated into style
sheets. Providing an equivalent alternative is mandatory at the time
of inserting some elements.
Web authors may not be familiar with accessibility issues that arise when
creating Web content. Therefore, help and documentation must include
explanations of accessibility problems, and should demonstrate
solutions with examples.
Checkpoints:
6.1 Document all features that
promote the production of accessible content.
[Priority 1] (Checkpoint
6.1)
Ensure that accessibility solutions are present in all help text
descriptions of markup practices (e.g., HTML IMG
elements should appear with an "alt" attribute and a
"longdesc" attribute wherever appropriate).
Ensure that electronic documentation complies with the Web Content
Accessibility Guidelines 1.0 [WCAG10]
Link from help text to any automated correction utilities.
Provide examples of accessible design practices in online
tutorials.
Include help documentation for all accessible authoring practices
supported by the tool.
Link those mechanisms used to identify accessibility problems
(e.g., icons, outlining or other emphasis within the user interface)
to help files.
Sample: Amaya help pages for images and image maps
[AMAYA-HELP-IMG] include providing text alternatives as part of
the process. There is a help page on configuring Amaya, that
documents how to change the default keyboard bindings.
6.2 Ensure that creating
accessible content is a naturally integrated part of the documentation,
including examples. [Priority 2] (Checkpoint
6.2)
In help text, when explaining the accessibility issues related to
non-deprecated elements, emphasize appropriate solutions rather than
explicitly discouraging the use of the element.
Explain the importance of utilizing accessibility features
generally and for specific instances.
Take a broad view of accessibility-related practices; for example,
do not refer to text equivalents as being "for blind
authors" but rather as "for authors who are not viewing
images".
Avoid labelling accessibility features of the tool with a
"handicapped" icon, as this can give the impression that accessible
design practices only benefit disabled authors.
In help text, emphasize accessibility features that benefit
multiple groups. In particular the principles of supporting flexible
display and control choices have obvious advantages for the
emergence of hands free, eyes-free, voice-activated browsing devices
such as Web phone, the large number of slow Web connections, and Web
users who prefer text-only browsing to avoid "image clutter".
Provide examples of all accessibility solutions in help text,
including those of lower priority in WCAG 1.0 [WCAG10].
Implement context-sensitive help for all special accessibility
terms as well as tasks related to accessibility.
Document the tool's conformance to ATAG 1.0 [ATAG10].
Include current versions of, or links to relevant specifications
in the documentation (e.g. HTML 4 [HTML4], CSS [CSS2].) This is particularly relevant for
markup languages that are easily hand edited, such as most XML
languages [XML].
Include a tutorial specifically on checking for and correcting Web
accessibility problems.
Link to or provide URIs for more information on accessible Web
authoring, such as WCAG 1.0 [WCAG10], and other accessibility-related
resources.
Ensure that documentation examples conform to WCAG 1.0 [WCAG10],
at least to the level that the tool conforms to ATAG 1.0
[ATAG10].
Clearly label any examples that display practices that reduce
accessibility.
Sample: Accessible authoring features are added to the
documentation as they are incorporated into Amaya, as part of the
normal documentation of the relevant feature.
6.3 In a dedicated
section, document all features of the tool that promote the production of
accessible content. [Priority 3] (Checkpoint
6.3)
Sample: Amaya documentation has a basic accessibility
section.
The authoring tool is a software program with standard user interface
elements and as such must be designed according to relevant user interface
accessibility guidelines. When custom interface components are created, it is
essential that they be accessible through the standard access mechanisms for
the relevant platform so that assistive technologies can be used with
them.
Some additional user interface design considerations apply specifically to
Web authoring tools. For instance,
authoring tools must ensure that the author can edit (in an editing view) using one set of stylistic
preferences and publish using different styles. Authors with low vision may
need large text when editing but want to publish with a smaller default text
size. The style preferences of the editing view must not affect the markup of
the published document.
Authoring tools must also ensure that the author can navigate a document
efficiently while editing, regardless of disability. Authors who use screen
readers, refreshable braille displays, or screen magnifiers can make limited
use (if at all) of graphical artifacts that communicate the structure of the
document and act as signposts when traversing it. Authors who cannot use a
mouse (e.g., people with physical disabilities or who are blind) must use the
slow and tiring process of moving one step at a time through the document to
access the desired content, unless more efficient navigation methods are
available. Authoring tools should therefore provide an
editing view that conveys a sense of the overall structure and
allows structured navigation.
Note: Documentation, help files, and installation are part
of the software and need to be available in an
accessible form.
Checkpoints:
7.1 Use all applicable
operating system and accessibility standards and conventions (Priority 1 for
standards and conventions that are essential to accessibility; Priority 2
for those that are important to accessibility; Priority 3 for those that are
beneficial to accessibility). (Checkpoint
7.1)
The techniques for this checkpoint include references to checklists
and guidelines for a number of platforms and to general guidelines for
accessible
applications.
Not all of the guidelines and checklists for application
accessibility are prioritized according to their impact on
accessibility. For instance, the priorities in "The Microsoft
Windows Guidelines for Accessible Software Design"
[MS-SOFTWARE] are partially determined by a logo requirement
program. Therefore developers may need to compare the documents they
are using to other guidelines. WCAG 1.0 [WCAG10] and UAAG 1.0 [UAAG10]
both have priority systems that are directly compatible with the
priorities in [ATAG10].
User Interfaces are sometimes built as Web content, and, as such,
should follow the Web Content Accessibility Guidelines 1.0 [WCAG10]. Refer also to
guideline 1.
Guidelines for specific platforms include
Reference: "IBM Guidelines for Writing Accessible
Applications Using 100% Pure Java" [JAVA-ACCESS] R.
Schwerdtfeger, IBM Special Needs Systems.
Reference: "An ICE Rendezvous Mechanism for X Window
System Clients" [ICE-RAP], W. Walker. A description of how to use
the ICE and RAP protocols for X Window clients.
Reference: "Information for Developers About Microsoft
Active Accessibility" [MSAA] Microsoft Corporation.
Reference: "The Inter-Client communication conventions
manual" [ICCCM]. A protocol for communication between clients
in the X Window system.
Reference: "Lotus Notes accessibility guidelines" [NOTES-ACCESS] IBM Special Needs Systems.
Reference: "Java accessibility guidelines and
checklist" [JAVA-CHECKLIST] IBM Special
Needs Systems.
Reference: "The Java Tutorial. Trail: Creating a GUI with JFC/Swing" [JAVA-TUT]. An online tutorial that describes how
to use the Swing Java Foundation Class to build an accessible
User Interface.
Reference: "Macintosh Human Interface Guidelines" [APPLE-HI] Apple Computer Inc.
Reference: "The Microsoft Windows Guidelines for
Accessible Software Design" [MS-SOFTWARE].
Guidelines for specific software types include
Reference: "The Three-tions of Accessibility-Aware HTML
Authoring Tools" [ACCESS-AWARE], J. Richards.
Reference: "User Agent Accessibility Guidelines
(Working Draft)" J. Gunderson, I. Jacobs eds. (This is a work in
progress) [UAAG10]
General guidelines for producing accessible software include:
Reference: "Accessibility for applications designers"
[MS-ENABLE] Microsoft Corporation.
Reference: "Application Software Design Guidelines" [TRACE-REF] compiled by G. Vanderheiden. A
thorough reference work.
Reference: "Designing for Accessibility" [SUN-DESIGN] Eric Bergman and Earl Johnson. This
paper discusses specific disabilities including those related to
hearing, vision, and cognitive function.
Reference: "Requirements for Accessible Software
Design" [ED-DEPT] US Department of Education, version 1.1
March 6, 1997.
Reference: "Software Accessibility" [IBM-ACCESS] IBM Special Needs Systems
Reference: "Towards Accessible Human-Computer
Interaction" [SUN-HCI] Eric Bergman, Earl Johnson, Sun
Microsytems 1995. A substantial paper, with a valuable print
bibliography.
Reference: "What is Accessible Software" [WHAT-IS] James W. Thatcher, Ph.D., IBM, 1997. This
paper gives a short example-based introduction to the difference
between software that is accessible, and software that can be
used by some assistive technologies.
The following are common requirements for producing accessible
software. This list does not necessarily cover all requirements for
all platforms, and items may not apply to some software.
Provide documentation for all features of the tool.
Ensure that help functions are accessible.
Sample: Amaya is currently available for two platforms:
Unix and Windows. There is some work required on both platforms to
bring it into line with conventions, in particular to provide
conformance with the User Agent Guidelines [UAAG10], and to implement
Microsoft Active Accessibility [MSAA] in the Windows version. It is being
re-written to take advantage of the improved accessibility support
possible in Gnome (it currently uses Motif) in the Unix version. The
Documentation is all available online as HTML and has been reviewed
to ensure it conforms to WCAG 1.0 [WCAG10].
7.2 Allow the author to change
the presentation within editing
views without affecting the document markup.
[Priority 1] (Checkpoint
7.2)
This allows the author to edit the document according to personal
requirements, without changing the way the document is rendered when
published.
In representing the source structure of a document mark elements
with text brackets rather than with purely graphic representations.
For example, "</>" is regarded as a text bracket, since it is
made of character elements.
Allow the author to create audio style sheets using a graphical
representation rather than an audio one (with accessible
representation, of course).
An authoring tool that offers a "rendered view" of a document,
such as a browser preview mode, may provide an editing view whose
presentation can be controlled independently of the rendered
view.
A WYSIWYG editor may allow an author to specify a local
style sheet, that will override the "published" style of the
document in the editing view.
Sample: Amaya allows the author to create local style
sheets, and to enable or disable each style sheet that is linked to
a document.
An authoring tool may offer several editing views of the same
document, such as a source mode that allows direct editing of all
properties.
Allow the author to individually edit each attribute of the
elements in an HTML or XML document, for example, through a menu.
Note: This must include the ability to add valid
values for attributes that are not present, as well as changing
current values of attributes.
For a site management tool, allow the author to render a site map
in text form (e.g., as a structured tree file).
Allow the author to specify that alternative information (or
identifiers such as a URI or filename) are rendered in place of
images or other multimedia content while editing.
Include attributes / properties of elements in a view of the
structure.
Provide access to a list of properties via a "context menu" for
each element.
Graphically represented elements cannot be identified by assistive
technologies that render text as braille, speech, or large print,
unless there is appropriate information available as text. For
example, some HTML authoring tools render start and end tags as
graphics. Such tag representations need to have a text equivalent to
be accessible to assistive technologies.
Sample: Amaya allows each attribute to be edited through
the menu or through the structure view. Element types can be
assigned through the menu system.
7.4 Ensure that the editing view allows navigation via
the structure of the document in an accessible fashion. [Priority 1] (Checkpoint
7.4)
Some tools, such as those used to translate from one format to
another, do not have an editing view.
Allow the author to navigate via an "outline" or "structure" of
the document being edited. This is particularly important for people
who are using a slow interface such as a small braille device, or
speech output, or a single switch input device. It is equivalent to
the ability provided by a mouse interface to move rapidly around the
document.
To minimally satisfy this checkpoint, allow navigation from
element to element.
In a hypertext document allow the author to navigate among links
and active elements of a document.
For SMIL and other time-based presentations, allow the author to
navigate temporally through the presentation.
Allow the author to navigate regions of an image, or the document
tree for an image expressed in a structured language such as
Scalable Vector Graphics [SVG].
Implement the HTML "accesskey" attribute, and
activate it in editing views
Sample: Amaya provides a structure view, that can be
navigated element by element, a Table of Contents view, that allows
navigation via the headings, and a links view, that allows
sequential navigation via the links in the document. It also
provides configurable keyboard navigation of the HTML structure -
parent, child, next and previous sibling elements.
7.5 Enable editing of the structure
of the document in an accessible fashion. [Priority 2] (Checkpoint
7.5)
An authoring tool may offer a structured tree view of the
document, allowing the author to move among, select and cut, copy or
paste elements of the document.
A WYSIWYG tool may allow elements to be selected, and
copied or moved while retaining their structure.
A tool may allow transformation from one element type to another,
such as
HTML paragraphs to lists and back;
HTML BR to P;
SMIL transformations between switch,
excl, and par;
HTML (deprecated) FONT into heuristically
determined structure;
Lists of lists to tables and back;
MathML transformations between semantic and presentation
markup;
Transforming the SVG g element to
symbol;
Giving a structural role to a part of an element, such as an
SVG g or an HTML p element.
Sample: Amaya allows the author to select elements (including
containers) and cut, copy and paste them with their attributes and
properties in any of the formatted, structure and alternate
views.
Search functions are already present in almost every text and
hypertext editing tools. The simplest allow searching for a sequence
of characters, while more powerful searches can include the ability
to perform searches that are case sensitive or case-insensitive, the
ability to replace a search string, the ability to repeat a previous
search to find the next or previous occurrence, or to select
multiple occurrences with a single search.
The ability to search for a particular type of structure is useful
in a structured document, structured image such as a complex SVG
image, etc.
In an image editor, the ability to select an area by properties
(such as color, or closeness of color) is useful. This is common in
middle range and high end image processing software.
The ability to search a database for particular content, or to
search a collection of files at once (a simple implementation of the
latter is the Unix function "grep") is an important tool in managing
large collections, especially those that are dynamically converted
into Web content.
The use of metadata (per WCAG 1.0 [WCAG10]) can allow for very complex
searching of large collections, or of timed presentations. Refer
also to the paper "A Comparison of Schemas for Dublin Core-based
Video Metadata Representation" [SEARCHABLE] for discussion
specifically addressing timed multimedia presentations.
Sample: Amaya provides a search function. Because all
editing views are synchronized, any search text found will be
selected in each of the available views.
Within these guidelines, "accessible Web content" and "accessible
authoring tool" mean that the content and tool can be used by people
regardless of disability.
To understand the accessibility issues relevant to authoring tool
design, consider that many authors may be creating content in contexts
very different from your own:
They may not be able to see, hear, move, or may not be able to
process some types of information easily or at all;
They may have difficulty reading or comprehending text;
They may not have or be able to use a keyboard or mouse;
They may have a text-only display, or a small screen.
Accessible design will benefit people in these different authoring
scenarios and also many people who do not have a physical disability but
who have similar needs. For example, someone may be working in a noisy
environment and thus require an alternative representation of audio
information. Similarly, someone may be working in an eyes-busy
environment and thus require an audio equivalent to information they
cannot view. Users of small mobile devices (with small screens, no
keyboard, and no mouse) have similar functional needs as some users with
disabilities.
An "accessibility-aware" application is one that
has been designed to account for authors' differing needs, abilities,
and technologies. In the case of authoring tools, this means that (1)
care has been taken to ensure that the content produced by user-authors
is accessible and (2) that the user interface has been designed to be
usable with a variety of display and control technologies.
"Accessibility information" is content, including information and
markup, that is used to improve the accessibility of a document.
Accessibility information includes, but is not limited to, equivalent alternative
information.
Inaccessible Web content or authoring tools cannot be used by some
people with disabilities. The Web Content Accessibility Guidelines 1.0
[WCAG10]
describes how to create accessible Web content.
"Accessible authoring practices" improve the accessibility of Web
content. Both authors and tools engage in accessible authoring
practices. For example, authors write clearly, structure their content,
and provide navigation aids. Tools automatically generate valid markup
and assist authors in providing and managing appropriate equivalent
alternatives.
An "alert" draws the author's attention to an event or situation. It
may require a response from the author. An
alert warns the author that there are problems that need to be
addressed. Attracting the author's attention artfully can be
challenging, since author perceptions of alerts, prompts, and warnings
can influence opinions of the tool and even of accessible
authoring.
An Unintrusive
Alert is an alert such as an icon, underlining, or gentle
sound that can be presented to the author without necessitating
immediate action. For example, in some word processors misspelled text
is highlighted without forcing the author to make immediate corrections.
These alerts allow authors to continue editing with the knowledge that
problems will be easy to identify at a later time. However, authors may
become annoyed at the extra formatting or may choose to ignore the
alerts altogether.
An Interruptive Alert
is an informative message that interrupts the editing process for the
author. For example, interruptive alerts are often presented when an
author's action could cause a loss of data. Interruptive alerts allow
problems to be brought to the author's attention immediately. However,
authors may resent the constant delays and forced actions. Many people
prefer to finish expressing an idea before returning to edit its
format.
Content is "equivalent" to other content when both fulfill essentially
the same function or purpose upon presentation to the user. Equivalent
alternatives play an important role in accessible authoring practices
since certain types of content may not be accessible to all users (e.g.,
video, images, audio, etc.). Authors are encouraged to provide text
equivalents for non-text content since text may be rendered as
synthesized speech for individuals who have visual or learning
disabilities, as braille for individuals who are blind, or as graphical
text for individuals who are deaf or do not have a disability. For more
information about equivalent alternatives, please refer to the Web
Content Accessibility Guidelines WCAG 1.0 [WCAG10].
Text equivalents for still images can be short
("Site Map Link") or long (e.g., "Figure 4 shows that the population of
bacteria doubled approximately every twenty hours over the first one
hundred hours, increasing from about 1000 per milliliter to about 32,000
per milliliter."). Text equivalents for audio clips are called "text
transcripts". Captions are essential text equivalents
for movie audio. Another essential text equivalent for a movie is a "collated text
transcript." An essential non-text equivalent for movies is
"auditory description"
of the key graphical elements of a presentation.
This document uses the term "attribute" as used in SGML and XML ([XML]): Element types
may be defined as having any number of attributes. Some attributes are
integral to the accessibility of content (e.g., the "alt",
"title", and "longdesc" attributes in
HTML).
In the following example, the attributes of the
beverage element type are "flavour", which
has the value "lots", and "colour", which has the value
"red":
An "auditory description" provides information about actions, body
language, graphics, and scene changes in a video. Auditory descriptions
are commonly used by people who are blind or have low vision, although
they may also be used as a low-bandwidth equivalent on the Web. An
auditory description is either a pre-recorded human voice or a
synthesized voice (recorded or automatically generated in real time).
The auditory description must be synchronized with the auditory track of
a video presentation, usually during natural pauses in the auditory
track.
An "authoring tool" is any software that is used to produce content
for publishing on the Web. Authoring tools include:
Editing tools specifically designed to produce Web content (e.g.,
WYSIWYG HTML and XML editors);
Tools that offer the option of saving material in a Web format
(e.g., word processors or desktop publishing packages);
Tools that transform documents into Web formats (e.g., filters to
transform desktop publishing formats to HTML);
Tools that produce multimedia, especially where it is intended for
use on the Web (e.g., video production and editing suites, SMIL
authoring packages);
Tools for site management or site publication, including tools
that automatically generate Web sites dynamically from a database,
on-the-fly conversion and Web site publishing tools;
Tools for management of layout (e.g., CSS formatting tools).
"Automated markup insertion functions" are the
features of an authoring tool that allow the author to produce markup
without directly typing it. This includes a wide range of tools from
simple markup insertion aids (such as a bold button on a toolbar) to
markup managers (such as table makers that include powerful tools such
as "split cells" that can make multiple changes) to high level site
building wizards that produce almost complete documents on the basis of
a series of author preferences.
"Captions" are essential text equivalents for movie audio.
Captions consist of a text
transcript of the auditory track of the movie (or other video
presentation) that is synchronized with the video and auditory tracks.
Captions are generally rendered graphically and benefit people who can
see but are deaf, hard-of-hearing, or cannot hear the audio.
A "conversion tool" is any application or application feature (e.g.,
"Save as HTML") that transforms convent in one format to another format
(such as a markup language).
As used in checkpoint 4.1, "check for" can refer to three types
of checking:
In some instances, an authoring tool will be able to check for
accessibility problems automatically. For example, checking for
validity (checkpoint 2.2) or testing whether an image is
the only content of a link.
In some cases, the tool will be able to "suspect" or "guess" that
there is a problem, but will need confirmation from the author. For
example, in making sure that a sensible reading order is preserved a
tool can present a linearized version of a page to the author.
In some cases, a tool must rely mostly on the author, and can only
ask the author to check. For example, the tool may prompt the author
to verify that equivalent alternatives for multimedia are
appropriate. This is the minimal standard to be satisfied. Subtle,
rather than extensive, prompting is more likely to be effective in
encouraging the author to verify accessibility where it cannot be
done automatically.
When several views co-exist, each may have a selection, but only one
is active, called the "current user selection." User selections may be
rendered specially (e.g., graphically highlighted).
A "description link", or D-Link, is an
author-supplied link to additional information about a piece of content
that might otherwise be difficult to access (image, applet, video,
etc.).
"Editing an element" involves making changes to one
or more of an element's attributes or properties. This applies to all
editing, including, but not limited to, direct coding in a text editing
mode, making changes to a property dialog or direct User Interface
manipulation.
An "element" is any identifiable object within a document, for
example, a character, word, image, paragraph or spreadsheet cell. In [HTML4] and [XML], an element
refers to a pair of tags and their content, or an "empty" tag - one that
requires no closing tag or content.
The "focus" designates the active element (e.g.,
link, form control, element with associated scripts, etc.) in a view
that will react when the user next interacts with the document.
A "generation tool" is a program or script that
produces automatic markup "on the fly" by following a template or set of
rules. The generation may be performed on either the server or client
side.
"Inserting an element" involves placing that
element's markup within the markup of the file. This applies to all
insertions, including, but not limited to, direct coding in a text
editing mode, choosing an automated insertion from a pull-down menu or
tool bar button, "drag-and-drop" style insertions, or "paste"
operations.
A "multimedia authoring tool" is software that
facilitates integration of diverse media elements into an comprehensive
presentation format. Multimedia includes video, audio, images,
animations, simulations, and other interactive components.
"Presentation markup" is markup
language that encodes information about the desired
presentation or layout of the content. For example, Cascading Style
Sheets ([CSS1],
[CSS2]) can be
used to control fonts, colors, aural rendering, and graphical
positioning. Presentation markup should not be used in place of structural
markup to convey structure. For example, authors should mark
up lists in HTML with proper list markup and style them with CSS (e.g.,
to control spacing, bullets, numbering, etc.). Authors should not use
other CSS or HTML incorrectly to lay out content graphically so that it
resembles a list.
A "prompt" is a request for author input, either information or a
decision. A prompt requires author response. For example, a text equivalent entry
field prominently displayed in an image insertion dialog would
constitute a prompt. Prompts can be used to encourage authors to provide
information needed to make content accessible (such as alternative text
equivalents).
A "property" is a piece of information about an element, for example
structural information (e.g., it is item number 7 in a list, or plain
text) or presentation information (e.g., that it is marked as bold, its
font size is 14). In XML and HTML, properties of an element include the
type of the element (e.g., IMG or DL), the
values of its attributes, and
information associated by means of a style sheet. In a database,
properties of a particular element may include values of the entry, and
acceptable data types for that entry.
A "publishing tool" is software that allows content
to be uploaded in an integrated fashion. Sometimes these tools makes
changes such as local hyper-reference modifications. Although these
tools sometimes stand alone, they may also be integrated into site
management tools.
The "rendered content" of an element is that which
the element actually causes to be rendered by the user agent. This may
differ from the element's structural content. For example, some elements
cause external data to be rendered (e.g., the IMG element
in [HTML4]),
and in some cases, browsers may render the value of an attribute (e.g.,
"alt", "title") in place of the element's
content.
A "selection" is a set of elements identified for a
particular operation. The user selection identifies a set of elements
for certain types of user interaction (e.g., cut, copy, and paste
operations). The user selection may be established by the user (e.g., by
a pointing device or the keyboard) or via an accessibility Application
Programmatic Interface (API). A view may have several selections, but
only one user selection.
A "site management tool" provides an overview of an
entire Web site indicating hierarchical structure. It will facilitate
management through functions that may include automatic index creation,
automatic link updating, and broken link checking.
"Structural markup" is markup
language that encodes information about the structural role
of elements of the content. For example, headings, sections, members of
a list, and components of a complex diagram can be identified using
structural markup. Structural markup should not be used incorrectly to
control presentation or layout. For example, authors should not use the
BLOCKQUOTE element in HTML [HTML4] to achieve an indentation visual layout
effect. Structural markup should be used correctly to communicate the
roles of the elements of the content and presentation
markup should be used separately to control the presentation
and layout.
A "transcript" is a text representation of sounds in an audio clip or
an auditory track of a multimedia presentation. A "collated text
transcript" for a video combines (collates) caption text with text
descriptions of video information (descriptions of the actions, body
language, graphics, and scene changes of the visual track). Collated
text transcripts are essential for individuals who are deaf-blind and
rely on braille for access to movies and other content.
A "transformation" is a process that changes a document or object into
another, equivalent, object according to a discrete set of rules. This
includes conversion
tools, software that allows the author to change the DTD defined for the original
document to another DTD,
and the ability to change the markup of lists and convert them into
tables.
A "user agent" is software that retrieves and renders Web content.
User agents include browsers, plug-ins for a particular media type, and
some assistive technologies.
A "user-configurable schedule" allows the user to
determine the type of prompts and alerts that are used, including when
they are presented. For example, a user may wish to include multiple
images without being prompted for alternative information, and then
provide the alternative information in a batch process, or may wish to
be reminded each time they add an image. If the prompting is done on a
user-configurable schedule they will be able to make that decision
themselves. This technique allows a tool to suit the needs a wide range
of authors.
A "video editor" is software for manipulating video
images. Video editing includes cutting segments (trimming),
re-sequencing clips, and adding transitions and other special
effects.
Authoring tools may render the same content in a variety of ways; each
rendering is called a "view." Some authoring tools will have several
different types of view, and some allow views of several documents at
once. For instance, one view may show raw markup, a second may show a
structured tree, a third may show markup with rendered objects while a
final view shows an example of how the document may appear if it were to
be rendered by a particular browser. A typical way to distinguish views
in a graphic environment is to place each in a separate window.
Many thanks to the following people who have contributed through review and
comment: Jim Allan, Denis Anson, Kitch Barnicle, Kynn Bartlett, Harvey
Bingham, Judy Brewer, Carl Brown, Dick Brown, Wendy Chisholm, Aaron Cohen, Rob
Cumming, Daniel Dardailler, Mark Day, BK Delong, Martin Dürst, Kelly Ford,
Jamie Fox, Edna French, Sylvain Galineau, Al Gilman, Jon Gunderson, Eric
Hansen, Phill Jenkins, Len Kasday, Brian Kelly, Marja-Riitta Koivunen, Sho
Kuwamoto, Jaap van Lelieveld, Susan Lesch, William Loughborough, Greg Lowney,
Karen McCall, Thierry Michel, Charles Oppermann, Dave Pawson, Dave Poehlman,
Loretta Reid, Bruce Roberts, Chris Ridpath, Gregory Rosmaita, Bridie Saccocio,
Janina Sajka, John Slatin, Jim Thatcher, Irčne Vatton, Gregg Vanderheiden,
Pawan Vora, Jason White, and Lauren Wood.
Amaya, developed at W3C, is both an authoring tool and browser with a
WYSIWYG-style user interface. Amaya serves as a testbed
for W3C specifications. Source code, binaries, and further information
are available at http://www.w3.org/Amaya/. The
techniques in this document are based on Amaya version 2.4.
The A-prompt tool allows authors to check many accessibility features
in HTML pages, and incorporates an "Alternative Information Management
Mechanism" (AIMM)) to manage equivalent alternative
information for known resources. The tool is built in such a way that
the functions can be incorporated into an authoring tool. A-prompt tool
is a freely available example tool developed by the Adaptive Technology
Resource Center at the University of Toronto, and the TRACE center at
the University of Wisconsin. The source code for the tool is also
available at http://aprompt.snow.utoronto.ca.
"CSS, level 1
Recommendation," B. Bos and H. Wium Lie, eds., 17 December 1996,
revised 11 January 1999. This CSS1 Recommendation is
http://www.w3.org/TR/1999/REC-CSS1-19990111. The latest version of CSS1 is
available at http://www.w3.org/TR/REC-CSS1. Note: CSS1
has been superseded by CSS2. Tools should implement the CSS2
cascade.
"CSS, level 2
Recommendation," B. Bos, H. Wium Lie, C. Lilley, and I. Jacobs,
eds., 12 May 1998. This CSS2 Recommendation is
http://www.w3.org/TR/1998/REC-CSS2-19980512. The latest version of CSS2 is
available at http://www.w3.org/TR/REC-CSS2.
"HTML 4.01
Recommendation," D. Raggett, A. Le Hors, and I. Jacobs, eds., 24
December 1999. This HTML 4.01 Recommendation is
http://www.w3.org/TR/1999/REC-html401-19991224. The latest version of HTML 4 is
available at http://www.w3.org/TR/html4.
"Mathematical
Markup Language," P. Ion and R. Miner, eds., 7 April 1998, revised 7
July 1999. This MathML 1.0 Recommendation is
http://www.w3.org/TR/1998/REC-MathML-19990707. The latest version of MathML 1.0
is available at http://www.w3.org/TR/REC-MathML.
"Ruby
Annotation," M. Sawicki, M. Suignard, M. Ishikawa, and M. Dürst,
eds. The 17 December 1999 Working Draft is
http://www.w3.org/TR/1999/WD-ruby-19991217. The latest version is
available at http://www.w3.org/TR/ruby.
"Designing for
Accessibility," Eric Bergman and Earl Johnson. This paper discusses
specific disabilities including those related to hearing, vision, and
cognitive function.
"User Agent Accessibility
Guidelines," J. Gunderson and I. Jacobs, eds. The latest version of
the User Agent Accessibility Guidelines is available at
http://www.w3.org/WAI/UA/UAAG10.
"What is
Accessible Software," James W. Thatcher, Ph.D., IBM, 1997. This
paper gives a short example-based introduction to the difference between
software that is accessible, and software that can be used by some
assistive technologies.
