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Technique G69:Providing an alternative for time based media

About this Technique

This technique relates to:

This technique applies to all technologies.

Description

The purpose of this technique is to provide an accessible alternative way of presenting the information in a synchronized media presentation.

In a synchronized media presentation, information is presented in a variety of ways including:

  • dialogue,
  • sounds (natural and artificial),
  • the setting and background,
  • the actions and expressions of people, animals, etc.,
  • text or graphics,
  • and more.

In order to present the same information in accessible form, this technique involves creating a document that tells the same story and presents the same information as the synchronized media. Such a document is sometimes called a screenplay. It includes all the important dialogue and actions as well as descriptions of backgrounds etc. that are part of the story.

If an actual screenplay was used to create the synchronized media in the first place, this can be a good place to start. In production and editing however, the synchronized media usually changes from the screenplay. For this technique, the original screenplay would be corrected to match the dialogue and what actually happens in the final edited form of the synchronized media.

In addition, some special types of synchronized media include interaction that has to occur at particular places in the playing of the synchronized media. Sometimes it may result in an action taking place (e.g., something is purchased, sent, done, etc.). Sometimes it may change the course of the synchronized media (e.g., the synchronized media has multiple paths that are determined by user input). In those cases links or some other mechanism would be used in the alternative for time-based media to allow people using the alternative to be able to have the same options and abilities as those using the synchronized media.

Examples

  • A training film shows employees how to use a new piece of equipment. It involves a person talking throughout while they demonstrate the operation. The screenplay used to create the training film is used as a starting point. It is then edited and corrected to match the dialogue etc. The film and the resulting alternative for time-based media are then made available on the company Web site. Employees can then use either or both to learn how to use the machine.
  • An interactive shopping environment is created that allows users to steer themselves around in a virtual store and shop. An alternative for time-based media allows the users to access the same shopping in text with links to choose aisles and to purchase things instead of dragging them into a virtual shopping basket.

Tests

Procedure

  1. View the synchronized media presentation while referring to the alternative for time-based media.
  2. Check that the dialogue in the alternative for time-based media matches the dialogue in the synchronized media presentation.
  3. Check that the alternative for time-based media has descriptions of sounds.
  4. Check that the alternative for time-based media has descriptions of setting and setting changes.
  5. Check that the alternative for time-based media has descriptions of actions and expressions of any 'actors' (people, animals etc).
  6. If the alternate version(s) are on a separate page, check for the availability of link(s) to allow the user to get to the other versions.

Expected Results

  • #2, 3, 4, 5 are true.

Test Rules

The following are Test Rules related to this Technique. It is not necessary to use these particular Test Rules to check for conformance with WCAG, but they are defined and approved test methods. For information on using Test Rules, see Understanding Test Rules for WCAG Success Criteria.

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