Understanding Success Criterion 1.2.2: Captions (Prerecorded)

Success Criterion 1.2.2 Captions (Prerecorded) (Level A): Captions are provided for all prerecorded audio content in synchronized media, except when the media is a media alternative for text and is clearly labeled as such.

Intent

The intent of this Success Criterion is to enable people who are deaf or hard of hearing to watch synchronized media presentations. Captions provide the part of the content available via the audio track. Captions not only include dialogue, but identify who is speaking and include non-speech information conveyed through sound, including meaningful sound effects.

It is acknowledged that at the present time there may be difficulty in creating captions for time-sensitive material and this may result in the author being faced with the choice of delaying the information until captions are available, or publishing time-sensitive content that is inaccessible to the deaf, at least for the interval until captions are available. Over time, the tools for captioning as well as building the captioning into the delivery process can shorten or eliminate such delays.

Captions are not needed when the synchronized media is, itself, an alternate presentation of information that is also presented via text on the Web page. For example, if information on a page is accompanied by a synchronized media presentation that presents no more information than is already presented in text, but is easier for people with cognitive, language, or learning disabilities to understand, then it would not need to be captioned since the information is already presented on the page in text or in text alternatives (e.g., for images).

See also 1.2.1: Captions (Live).

Benefits

Examples

Related Resources

Resources are for information purposes only, no endorsement implied.

Guides to Captioning

SMIL Resources

Other Captioning Resources

Captioning Tools

Techniques

Each numbered item in this section represents a technique or combination of techniques that the WCAG Working Group deems sufficient for meeting this Success Criterion. However, it is not necessary to use these particular techniques. For information on using other techniques, see Understanding Techniques for WCAG Success Criteria, particularly the "Other Techniques" section.

Sufficient Techniques

  1. Providing open (always visible) captions
  2. Providing closed captions using any readily available media format that has a video player that supports closed captioning
  3. Providing closed captions using any of the technology-specific techniques below

Advisory Techniques

Although not required for conformance, the following additional techniques should be considered in order to make content more accessible. Not all techniques can be used or would be effective in all situations.

  • Providing a note saying "No sound is used in this clip" for video-only clips (future link)
  • Using SMIL 1.0 to provide captions for all languages for which there are audio tracks (future link)
  • Using SMIL 2.0 to provide captions for all languages for which there are audio tracks (future link)

Failures

The following are common mistakes that are considered failures of this Success Criterion by the WCAG Working Group.

Key Terms

audio

the technology of sound reproduction

Audio can be created synthetically (including speech synthesis), recorded from real world sounds, or both.

media alternative for text

media that presents no more information than is already presented in text (directly or via text alternatives)

A media alternative for text is provided for those who benefit from alternate representations of text. Media alternatives for text may be audio-only, video-only (including sign-language video), or audio-video.

prerecorded

information that is not live

synchronized media

audio or video synchronized with another format for presenting information and/or with time-based interactive components, unless the media is a media alternative for text that is clearly labeled as such