Guide to Guideline 1.1, Level 1, SC #2

Success criterion: What WCAG 2.0 requires

For all non-text content that is used to convey information, text alternatives convey the same information.

Note: for multimedia, this means that two alternatives are provided:

  1. a transcript
  2. a text alternative that identifies the purpose or function of the multimedia

Understanding this Success Criterion

Key terms and important concepts

text alternative

A text alternative

  • serves the same function as the non-text content was intended to serve.
  • communicates the same information as the non-text content was intended to convey.
  • may contain structured content or metadata.

Note: text alternatives should be easily convertible to braille or speech, displayed in a larger font or different colors, fed to language translators or abstracting software, etc.

Intent of this success criterion

Ensure that critical information presented visually or auditorilly is also available in text. End-users who are unable to interpret graphs are @@how it differs from the others. e.g., "functional" and "specific sensory experience." How know when to apply this instead of "can be ignored?" Also will need to reference "explicitly associated." Although, that criterion applies to all...kind of a address?

Applicability: When does this Success Criterion Apply?

When non-text content contains information that is necessary to understanding or interacting with the content (@@too broad).

To determine the information conveyed by non-text content:

[@@ need to draft: What does the content provider want people to learn from the non-text content? What does the user need to learn from the text alternative? Is it important for users to draw their own conclusions based on the content as well as understanding the specific point the content-provider wanted to make?]

Techniques to meet this Success Criterion

Technology-Independent techniques for this Success Criterion

[@@example of linking to general techniques instead of including in-line. These are examples of the type of content we could link to, it is not the final form....THESE ARE JUST EXAMPLES FOR DISCUSSION AND TO COMPARE WITH OTHER APPROACHES]

Technology-Specific Techniques for this Success Criterion

Advisory techniques: going beyond this Success Criterion

@@not sure what to recommend here

Benefits for People with Disabilities

Examples of this Success Criterion

@@need to clean these up.

A photograph of an historic event adds to a news story

A photograph of two world leaders shaking hands accompanies a news story about an international summit meeting. The text alternative says, “President X of Country X shakes hands with Prime Minister Y of country Y."

A photograph of an historic event illustrates diplomacy

The same image of two world leaders shaking hands appears on a Web site discussing intricate diplomatic relationships. The first text alternative reads, “President X of country X shakes hands with Prime Minister Y of country Y on January 2, 2009.” An additional text alternative describes the room where the leaders are standing, the expressions on the leaders' faces, and identifies the other people in the room.

An audio recording of an historic event provides verbatim record

The Web page described in the previous example includes a link to an audio recording of the leaders' press conference. The page links to a text transcript of the press conference. The transcript includes a verbatim record of everything the speakers say. It identifies who is speaking as well as noting other significant sounds that are part of the recording, such as applause, laughter, questions from the audience, and so on.

A bar chart compares sales by month

A bar chart compares how many widgets were sold in June, July, and August. The short label says, "Figure one - Sales in June, July and August." The longer description identifies the type of chart, provides a high-level summary of the data comparable to that available from the chart, and provides the data in a table.

An animation demonstrates how a car engine works

There is no audio and the animation is part of a tutorial that describes how an engine works. All that is needed is a description of the image. From "How car engines work: Internal combustion@@link"

Note: Further discussion and examples are needed for real-time silent video such as webcams.