Soon, the deaf can talk on mobile!

A revolution is in the offing for hearing-impaired people with scientists testing a new mobile device which they claim will transmit American Sign Language over cellular networks.

Developed by engineers at the University of Washington (UW), MobileASL uses motion detection technology to identify American Sign Language (ASL) and transmit video images over cell networks in the US.

The tool, which can be integrated to any high-end mobile phone with a video camera, is undergoing field tests involving 11 participants and the researchers plan to launch a larger field study this winter. "This is the first study of how deaf people in the US use mobile video phones," said project leader Eve Riskin, a UW professor of electrical engineering.

According to the university, the engineers are now working to optimise compressed video signals for sign language, increasing the quality of the images around the face and hands to reduce the data rate to 30 kilobytes per second.

To minimise the amount of battery power, the MobileASL phones employ motion sensors to determine whether sign language is being used, it said.

Transmitting sign language as efficiently as possible increases affordability, improves reliability on slower networks and extends battery life, even on devices that might have the capacity to deliver higher quality video.

And the field test is allowing the team to see how people use the tool in their daily lives and what obstacles they encounter. "We know these phones work in a lab setting, but conditions are different in people's everyday lives," Riskin said.

"The field study is an important step toward putting this technology into practice." Texting or e-mail is currently the preferred method for distance communication of deaf and hearing-impaired people. But the participants' experiences with the MobileASL phone are, in general, positive.

"It is good for fast communication," said Tong Song, a Chinese national who is studying at Gallaudet University in Washington, DC. "Texting sometimes is very slow, because you send the message and you're not sure that the person is going to get it right away.

If you're using this kind of phone then you're either able to get in touch with the person or not right away, and you can save a lot of time."

According to the researchers, newly released high-end phones, such as the iPhone 4 and the HTC Evo, offer video conferencing. But broadband companies are now blocking the heavy-bandwidth conferencing from their networks and introducing tiered pricing plans to account for heavy data usage.

But Riskin said they "want to deliver affordable, reliable ASL on as many devices as possible. It's a question of equal access to mobile communication technology." The MobileASL system, the researches said, could be integrated with the iPhone 4, the HTC Evo, or any device that has a video camera on the same side as the screen.