Pushed by Congress and the Federal Communications Commission, the TV industry has gradually adapted its programs to accommodate people who can't hear.
But what about people who can't see? How can they "watch" TV?
A handful of companies and nonprofit organizations are providing an answer. They're recording special audio tracks, called video descriptions, that can fill some of the gaps between lines of dialogue.
Although video descriptions are relatively scarce today, the situation could change dramatically next year. That's when the major broadcast and cable TV networks in the 25 largest cities are scheduled to add descriptions to part of their lineups, as ordered by the FCC.
The mandate might never take effect, however. Trade groups for the broadcasters, cable operators and movie studios have asked a federal appeals court to throw out the FCC's order, arguing that the regulators overstepped their authority and violated the 1st Amendment.
In the meantime, public broadcasting stations provide descriptions for about three hours of kids' shows daily and a few hours of prime-time programs each week. The Turner Classic Movie channel offers a movie with descriptions every day or two, and a number of older syndicated programs and movies on independent channels carry descriptions.
Most of the work on descriptions is being done by three groups: the Narrative Television Network of Tulsa, Okla.; public broadcaster WGBH in Boston; and RP International, a Woodland Hills-based association supporting research into degenerative eye disease. Those efforts are supported by a mix of federal grants, charitable contributions and volunteers.
In a program with video descriptions, a narrator will convey the setting and the action on screen whenever there's a break in the dialogue. For example, there's a scene in "The Lion King" when the cub Simba and his parents leave their den at daybreak. While the lions silently make their way, the narrator says, "Simba races outside, followed by his parents. Sarabi [the mother lion] smiles and nudges Simba gently toward his father. The two sit, side by side, watching the golden sunrise."
The extra narration is usually carried on a hidden audio track, called the Secondary Audio Program, much like text captions for the deaf are concealed within the standard video signal. Most TVs and stereo VCRs built since 1995 have the ability to tune in to SAP material.
Several of the networks have been using the SAP channel to offer Spanish versions of baseball games and other sports events. That means many broadcasters and cable operators already are equipped to deliver SAP-based video descriptions. However, it also illustrates the competition that video descriptions face for the secondary audio channel.
That's why RP International and Harris Corp. are backing an alternative approach that uses special equipment at the station and the home to deliver video descriptions. According to Brian C. Beck, director of strategic management for Harris, the video descriptions are embedded digitally into a TV signal without using the SAP channel or affecting the picture.
A set-top box receives the embedded data, transforms them back into something audible and transmits them to consumers' headphones. That way, a visually impaired person could listen to the extra narration without disturbing other viewers in the room.
One of the drawbacks to this approach is the additional costs it would impose on broadcasters and consumers. But the set-top box should cost no more than a basic VCR, Beck said, adding that broadcasters could use the data-embedding equipment for other, revenue-producing pursuits.
An early demonstration of the technology could come to a few thousand homes in Los Angeles this fall, Beck said. RP International and Harris also are developing a system to deliver and manage descriptions for movie theaters.
Just as the suppliers of video description are split on how best to do it, so are advocates for the blind divided on the FCC's mandate. Although RP International is a strong supporter, the National Federation for the Blind has asked the appeals court to block the mandate on the grounds that it is misplaced.
In an open letter, NFB President Marc Maurer argues that artists should be free to decide whether to provide descriptions for their visual works. Although emergency bulletins and related material should carry descriptions, Maurer wrote, "the FCC [should] not misapply the law by saying that entertainment cannot exist unless it is described."
The Motion Picture Assn. of America also objects on freedom-of-expression grounds, saying descriptions involve interpretation and emotion. "Captioning requires only production of a word-for-word translation of a work, but video description requires the creation of an entirely new artistic work," MPAA spokesman Rich Taylor said.
Bryan Boliver, a 17-year-old high school senior in Melbourne Beach, Fla., thinks descriptions are a bit more matter-of-fact than that. Legally blind, Boliver recently listened to a version of the movie "Titanic" with descriptions provided by RP International and Harris.
"It just fit what was happening completely," Boliver said. "It wasn't putting images in my head, it was just stating what was going on."
Helen Harris, who founded RP International after retinisis pigmentosa claimed her eyesight and afflicted two of her sons, said descriptions are a critical bridge that lets the blind share in the movies and TV shows their families and friends enjoy.
"I think the NFB is not speaking for the blind," she said. "Certainly not for me and people like me."
Times staff writer Jon Healey covers the convergence of technology and entertainment.