Device lets deaf phone users talk with sign language

Posted by Emma Woollacott

As many as two million people in the US alone could soon get the chance to use their native language on a cellphone for the first time.

University of Washington engineers are currently testing a device able to transmit American Sign Language over US cellular networks using a relatively narrow bandwidth.

The MobileASL team has been working to optimize compressed video signals for sign language. By increasing image quality around the face and hands, researchers have brought the data rate down to just  30KBps while still delivering intelligible sign language.

The system also uses motion detection to identify whether a person is signing or not, in order to extend the phones' battery life during video use.

"We know these phones work in a lab setting, but conditions are different in people's everyday lives," said project leader Eve Riskin, a UW professor of electrical engineering. "The field study is an important step toward putting this technology into practice."

Most study participants say texting or email is currently their preferred method for distance communication, and most said they liked the MobileASL phone.

"It is good for fast communication," said student Tong Song. "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."

Josiah Cheslik agreed.

"Texting is for short things, like 'I'm here,' or, 'What do you need at the grocery store?'" he said. "This is like making a real phone call."

Of course, many high-end smartphones offer video conferencing. But the costs can be high, as some broadband companies have blocked it from their networks and are rolling out tiered pricing plans that would charge more to heavy data users.

The UW team estimates that iPhone's FaceTime video conferencing service uses nearly 10 times the bandwidth of MobileASL. Even after the anticipated release of an iPhone app to transmit sign language, people would need to own an iPhone 4 and be in an area with very fast network speeds in order to use the service.

The MobileASL system 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.

"We want to deliver affordable, reliable ASL on as many devices as possible," Riskin said. "It's a question of equal access to mobile communication technology."