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Video and Multimedia
Products (1194.24)
Updated: June 21, 2001
 (a)
All analog television displays 13 inches and larger, and computer
equipment that includes analog television receiver or display circuitry,
shall be equipped with caption decoder circuitry which appropriately
receives, decodes, and displays closed captions from broadcast, cable,
videotape, and DVD signals. As soon as practicable, but not later
than July 1, 2002, widescreen digital television (DTV) displays measuring
at least 7.8 inches vertically, DTV sets with conventional displays
measuring at least 13 inches vertically, and stand-alone DTV tuners,
whether or not they are marketed with display screens, and computer
equipment that includes DTV receiver or display circuitry, shall be
equipped with caption decoder circuitry which appropriately receives,
decodes, and displays closed captions from broadcast, cable, videotape,
and DVD signals.
 What
are captions?
Like subtitles, captions display spoken dialogue as printed words
on a television screen or computer monitor. Unlike subtitles, captions
are specifically designed for hard-of-hearing and deaf viewers to
enable their full participation when viewing video or multimedia productions.
Captions are carefully placed to identify speakers. They often include
information regarding on- and off-screen sound effects, such as music
or laughter. Captions also hold secondary benefits for people who
are learning a foreign language, learning how to read, or watching
TV in a noisy area, as well as those who understand best by processing
visual information.
Captions come in two forms: open or closed captioning:
- Open captions are displayed automatically as part of
the video, without having to be selected by the user.
- Closed captions normally do not appear as part of the
video portion of a multimedia presentation unless the viewer has
selected them to appear. The person viewing the presentation must
be using technology that includes a closed caption decoder. The
decoder will allow the otherwise-hidden data within the television
signal to be displayed on the userâs TV screen or computer monitor.
Many newer television models allow viewers to toggle captions
on or off with ease.
What television display formats are required to include caption
decoder circuitry?
Analog and digital television displays, as well as stand-alone
digital television tuners and computer equipment that includes digital
television receiver or display circuitry, must include caption decoder
circuitry. Section 508 does not require small analog or digital television
displays to include caption decoder circuitry. Specifically, analog
televisions with screens smaller than 13 inches diagonally and DTVs
with displays smaller than 7.8 inches vertically are exempted. The
Television
Decoder Circuitry Act of 1990 and the Telecommunications
Act of 1996 contain similar provisions.
 Back
(b) Television tuners, including tuner cards for
use in computers, shall be equipped with secondary audio program playback
circuitry.
What is a secondary audio channel and why is special circuitry
required?
The most common method of broadcasting audio description is through
the Secondary Audio Program (SAP) feature of stereo televisions. Each
television channel has what is called a "secondary audio channel"
associated with it. The secondary audio channel may contain audio
descriptions or foreign language translations of dialogue. If used
to deliver audio descriptions, SAP can greatly enhance the multimedia
experience for those who are blind or who have low vision. When television
tuners, including tuner cards for use in computers, are equipped with
SAP playback circuitry, people who are blind or who have low vision
may access whatever audio description has been associated with the
presentation.
How do audio descriptions assist people with disabilities?
An "audio description" is an audible description of the visual
content of a presentation, synchronized with the existing soundtrack.
Typically, appropriate portions of the audio description are narrated
during what would otherwise be natural silences in the presentation.
 What
is a tuner card?
Tuner cards enable a computer to receive television broadcasts.
This product is an example of what the industry calls "convergence"
and represents a way in which the functions historically provided
by TV, PC, cable and Internet products are merging onto multi-function
devices. Tuner cards can be internal or external and can work with
laptop or desktop computers.
Back
(c) All training and informational video and multimedia
productions which support the agency's mission, regardless of format,
that contain speech or other audio information necessary for the comprehension
of the content, shall be open or closed captioned.
(d) All training and informational video and multimedia productions
that support the agency's mission, regardless of format, that contain
visual information necessary for the comprehension of the content,
shall be audio described.
What is a multimedia production?
The term "multimedia productions" refers to productions that present
information in more than one sensory mode, e.g., both audibly and
visually. For instance, streaming video with a soundtrack is a multimedia
production. A show broadcast through a Federal military radio station
is audio only and therefore not covered by this captioning requirement.
(However, the procurement of electronic and information technology
necessary to operate the radio station would be covered under the
508 standard.)
What does it mean for a video or multimedia production to "support
the agencyâs mission?"
Video and multimedia products that "support the agencyâs mission"are
generally required to be captioned and audio-described. For instance,
a training film for the Social Security Administration regarding how
agency personnel should determine an applicantâs eligibility for benefits,
is a training production that supports the agencyâs mission. A video
of a retirement celebration, on the other hand, would not be "in support
of an agency's mission" and is not covered by these provisions.
Raw videotaped footage recorded by a field investigator to document
a safety violation could be considered a film "in support of an agencyâs
mission". However, it is not a "production" and therefore does not
need to be captioned or audio described. On the other hand, if such
footage were subsequently incorporated into agency training or an
informational presentation, it would have to be captioned and audio
described.
 When
are captioning and audio descriptions required?
Captioning and audio descriptions are only required to be provided
when important to understand the audio or visual components of a video
or multimedia production. That is, even if a production "supports
the agencyâs mission," only those audio portions that are necessary
for the comprehension of the productionâs content need to be captioned.
Ex: A videotaped lecture would need to capture the lecturerâs words
in captions if it is intended to be used for future training, but
the captions need not also relate that studentsâ chairs were squeaking
or that the door at the back of the room was closing loudly as people
exited.
Similarly, only those visual portions that are necessary for the comprehension
of the productionâs content need to be audio described.
Ex: A videotaped lecture would need to include an audio description
of graphics the lecturer draws on a chalkboard to illustrate a point,
but would not need to include an audio description of the strictly
verbal ö or "talking heads" ö portion of the lecture.
If I believe that no one with a hearing loss will see the video,
do I still have to caption it?
Yes, unless an exception applies (e.g., electronic and information
technology that is part of a national security system is not required
to adhere to the Access Boardâs provisions), section 508 requires
accessibility features to be built into new multimedia products as
called for in this technical provision. Section 508 generally focuses
on how the technology is designed, rather than who may use it.
Agencies will likely find that captions will assist many nondisabled
individuals as well, including those who otherwise have normal hearing
but are "functionally hard of hearing" in rooms with poor acoustics
due to echos or noisy ventilation, those who are learning English
as a second language, and individuals with auditory processing disabilities.
Finally, many people simply learn best if information is presented
in more than one sensory mode, such as hearing while simultaneously
reading the dialogue.
Back
(e) Display or presentation of alternate text presentation
or audio descriptions shall be user-selectable unless permanent.
Does this provision apply differently to audio description than
it does to captioning?
Given the current state and prevalence of analog technology, the
"user-selectable" language generally applies to closed captioning,
which the viewer can turn on or off. Audio description on VHS format
videos is permanently encoded and is always "on." If a user wanted
to watch a video without listening to the audio description, he or
she would need to find a separate version of the production that was
not audio described. The same is true with open captioning.
CD-ROMs, DVDs, and other digital forms of multimedia can support alternate
audio channels for audio description. Using SMIL (Synchronized Multimedia
Integration Language) or other emerging technologies, captioning and
audio description will likely be more easily integrated into digital
multimedia presentations in the near future.
Another point bundled in this provision relates to difficulty users
have reported with independently enabling audio description. The means
of choosing alternate tracks for audio description varies by the medium,
but usually involves selection from an on-screen menu. Therefore those
menus must be made audible or otherwise readily selectable so that
people with visual disabilities can independently gain access to audio
descriptions.
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