Viral videos may be good for sharing ideas and spreading funny foreign pop hits, but they are also leaving millions of deaf and hearing-impaired people out of the loop.
Online video is becoming a more ubiquitous part of many peoples' life and YouTube expects 90 per cent of online traffic to be video in the next few years.
That video explosion has been great for small-film and television producers, who are able to reach an audience without a big studio budget, and fans of niche programming. But in some ways, it has left the deaf and hard-of-hearing community starting from scratch after years of advocating for captions on traditional television.
"We could be back to square one," said Christian Vogler, director of the Technology Access Programme at Gallaudet University in Washington DC.
The rise of emails, instant messages and social media was a godsend to the deaf and hard-of-hearing community, who embraced the new, text-based ways to communicate.
"In the mid-to-late 1990s, it was close to the ideal medium," Vogler said.
But as the web evolved to include more video, he said, old barriers to communication resurfaced.
In the United States, broadcasters and video services must provide online captions for sitcoms and dramas that first air on television under 2010 regulations adopted by the Federal Communications Commission but there are no such requirements for content made exclusively for the web.
Some companies have launched their own efforts. Netflix, after settling with the National Association of the Deaf, has committed to captioning all of its content by 2014. But that's a fraction of the online videos that drive the pop-culture conversation, including user-submitted videos on sites such as Google's YouTube.
"The video that people watch and talk about around the water cooler is less often, ‘Did you see the news report?' " said Blake Reid, a lawyer who has worked with advocacy groups for the deaf and hard of hearing. "It's, ‘Did you see that video going around on YouTube, that viral video?"'
The line between online video and television is becoming more arbitrary, advocates say, and federal regulations should reflect this shift.
"By and large, they are separate worlds at this point," Reid said. But that separation is disappearing, he added. "That's one of our next fronts to look at, but we're not there yet."
To tackle the problem, YouTube offers automatic captioning in English, Spanish, Japanese and Korean on many of its videos. And the company announced recently that it is extending the number of auto-caption languages, adding support for German, Italian, French, Portuguese, Russian and Dutch.
It's not an ideal solution. Speech-recognition software is far from perfect. Still, the company hopes that providing the captions will get more people focused on the issue.
"The real challenge is awareness," said Ken Harrenstien, a deaf Google engineer who has led the effort to get captions on YouTube videos.
YouTube users can also upload transcripts to accompany their videos. That makes the captioning process easier, clearing one of the hurdles to the effort, he said.
"Auto-captions aren't great but are better than nothing," he said. "The real value is in helping people create real captions from them."
Advocates for the deaf and hard of hearing call YouTube's efforts a good first step but say the technology has a long way to go.
"It doesn't replace quality captioning by itself," said James House, public relations director for Telecommunications for the Deaf and Hard of Hearing.
Last month, clips of an animated sign-language interpreter at New York Mayor Michael Bloomberg's news conference on Hurricane Sandy went viral, pulling the issue of communicating disaster information to the deaf and hard-of-hearing community into the spotlight.
Clips of that news conference had no captions - leaving those who don't sign, in the dark about the emergency information.
"In cases of emergencies, it [is] vital that we have all the information available to us," House said.
For now, advocates continue to work with industry providers such as Netflix and Hulu to provide captioning on all platforms.
Advocates say that although Google, Apple and other companies have taken it upon themselves to get ahead of the captioning curve, more regulation is necessary to get captions on the majority of videos.
"Voluntary efforts can come and go," House said.