Preamble: Multimedia

Let’s be realistic

  1. It’s unrealistic to expect authors to caption all their videoclips right away.
    1. They don’t have the expertise and certainly should not be encouraged to guess or dabble.
    2. Player complications are significant, and if the author provides video in multiple formats, then multiple incompatible caption formats will also be required.
    3. Authoring tools for Web captioning and description simply are not up to the task. Captioning itself is difficult and captioning software makes things worse.
    4. Sending video out of house for captioning costs hundreds or thousands of dollars per program hour. For many small and medium-size Web publishers, that constitutes undue hardship right there.
    5. In some languages and countries, there is no tradition or practice of captioning at all, even on television.
  2. It’s even more unrealistic to expect authors to describe all their videoclips right away.
    1. While captioning requires, at root, reading and transcription skills, description requires specific creative-writing ability plus a voice amenable to description and a means to record and mix that voice. (Using a speech synthesizer for description is not currently done and should be discouraged. Blind people listen to enough robotic speech already.)
    2. There are very few languages and countries in which audio description has a tradition or practice.
    3. Some programming genres, especially as found on the Web, do not urgently need description. Fictional narrative programming and documentaries – two genres classically associated with audio description – are uncommon online and will probably stay that way.

Improvement and phase-in

Those conditions will eventually improve. It will eventually become more common, and presumably easier and less expensive, to provide captions and descriptions online.

But multimedia online is unlike other Web content. Similarly, accessibility for multimedia is also different.

Consider the case of authors with inaccessible sites. They’re faced with going from 0% of compliant content (or some other low proportion) to 100%.

  1. It’s possible for authors to give themselves a deadline by which they will have fixed everything up in order to meet WCAG 2.0 – for content other than multimedia.
  2. But it would be highly unusual for an author to be able to meet multimedia requirements by a specific day (save for the case where very little multimedia is offered). That’s because captioning and description are time-consuming, expensive, and technically error-prone.

Thus, for content original to the Web, a phase-in period is required. For content reused from other media, though, captions and descriptions can be provided immediately with no phase-in. That kind of reused accessibility will in itself increase the available quantity of captioned and/or described online media by orders of magnitude.


  1. Transcription is not the way to make video accessible. The correct accessibility methods are captioning and audio description.
  2. A transcript is an artifact separate from the original, just as a talking book or large-print or Braille edition is separate from a printed book. But audiovisual media can and must carry their accessibility features with them.
  3. If an online video segment is provided with captions, a transcript can be added and offered later. A transcript must never be the sole method of accessibility for deaf and hard-of-hearing viewers. At best it can be supplemental.
  4. “Text descriptions” are meaningless and unheard of in audio description. They are a figment of the imagination with no benefit whatsoever to a blind or visually-impaired viewer. The medium of accessibility for that audience is sound and voice, not the written word. WCAG’s own guidelines require synchronized media equivalents. Transcripts are not synchronized.
  5. A “combined” caption transcript plus audio-description script has been attempted exactly once in known history (for a demonstration project that was never completed). There is no method to combine those two sources due, among other reasons, to a lack of interchange formats. The idea is a non-starter.

Reuse of existing captions and descriptions

  1. Authors should be required to reuse any captions or descriptions that were created for the original program.
  2. That means all TV programming captioned or described for television must carry its accessibility over to the Web.
  3. It’s technically straightforward, inexpensive, and almost immediately achievable, even for audio description.
  4. It’s already being done now.


  1. It’s unrealistic for WCAG to require all or even a specific percentage of captioned and described video immediately upon an author’s adoption of WCAG.
  2. It’s unrealistic to expect authors to zoom from a probable state of zero captioning and description to 100% or some other percentage overnight.
  3. Because of the unique nature of captioning and description – as with multimedia itself, both fields are dissimilar to other Web content – a phase-in period is required.

Multimedia: Recommendations

Reuse of captions and descriptions

Video content with a soundtrack that has been captioned and/or described in another medium must be captioned and/or described when presented online.

Requirements from other media



Audio description

Original Web content




  1. Don’t use colour as the sole method of indicating structure.
  2. Don’t use colour in a way that is likely to cause confusion among viewers with common colour deficiencies.
  3. Use foreground/background colour combinations that are likely to be legible for viewers with colour deficiencies. Optionally, include an accessible method by which the viewer can alter foreground/background combinations.