Browse Definitions :
Definition

closed captions

Contributor(s): Eric, Sally Carpenter

Closed captions are a text version of the spoken part of a television, movie, or computer presentation. Closed captioning was developed to aid hearing-impaired people, but it's useful for a variety of situations. For example, captions can be read when audio can't be heard, either because of a noisy environment, such as an airport, or because of an environment that must be kept quiet, such as a hospital.

Closed captioning information is encoded within the video signal, in line 21 of the vertical blanking interval ( VBI ). The text only becomes visible with the use of a decoder, which may be built into a television set or available as a set-top box . In general, an onscreen menu on newer televisions allows you to turn closed captioning on or off. Open captions, in contrast, are an integral part of a transmission that cannot be turned off by the viewer.

Most programs are captioned in advance of transmission, but the nature of some programs, such as live news broadcasts, requires real time captioning. For real time captioning, a stenographer listens to the broadcast and types a shorthand version into a program that converts the shorthand into captions and adds that data to the television signal.

According to the Television Decoder Circuitry Act of 1990, all televisions made in the United States since 1993 must have a built-in caption decoder if their picture tubes are larger than 13 inches. In July 2000, the Federal Communications Commission (FCC) mandated sections of industry standard EIA-708-B, "Digital Television ( DTV ) Closed Captioning" into its broadcast regulations. The new rules will make it possible for users to select the size, color, and font of their captions and to select among multiple streams, choosing, for example, a particular language.

This was last updated in September 2005

Join the conversation

1 comment

Send me notifications when other members comment.

Please create a username to comment.

Is all closed captioning originally done by a stenographer or there some automated way to caption?

Thanks

Cancel

-ADS BY GOOGLE

File Extensions and File Formats

SearchCompliance

  • compliance audit

    A compliance audit is a comprehensive review of an organization's adherence to regulatory guidelines.

  • regulatory compliance

    Regulatory compliance is an organization's adherence to laws, regulations, guidelines and specifications relevant to its business...

  • Whistleblower Protection Act

    The Whistleblower Protection Act of 1989 is a law that protects federal government employees in the United States from ...

SearchSecurity

  • RSA algorithm (Rivest-Shamir-Adleman)

    The RSA algorithm is the basis of a cryptosystem -- a suite of cryptographic algorithms that are used for specific security ...

  • remote access

    Remote access is the ability to access a computer or a network remotely through a network connection.

  • IP Spoofing

    IP spoofing is the crafting of Internet Protocol (IP) packets with a source IP address that has been modified to impersonate ...

SearchHealthIT

SearchDisasterRecovery

  • network disaster recovery plan

    A network disaster recovery plan is a set of procedures designed to prepare an organization to respond to an interruption of ...

  • virtual disaster recovery

    Virtual disaster recovery is a type of DR that typically involves replication and allows a user to fail over to virtualized ...

  • tabletop exercise (TTX)

    A tabletop exercise (TTX) is a disaster preparedness activity that takes participants through the process of dealing with a ...

SearchStorage

  • enterprise storage

    Enterprise storage is a centralized repository for business information that provides common data management, protection and data...

  • disk array

    A disk array, also called a storage array, is a data storage system used for block-based storage, file-based storage or object ...

  • optical storage

    Optical storage is any storage type in which data is written and read with a laser. Typically, data is written to optical media, ...

Close