27 August 2008

Sign Language Over Cell Phones

A group at the University of Washington has developed software that for the first time enables deaf and hard-of-hearing Americans to use sign language over a mobile phone. UW engineers got the phones working together this spring, and recently received a National Science Foundation grant for a 20-person field project that will begin next year in Seattle. This is the first time two-way real-time video communication has been demonstrated over cell phones in the United States. Since posting a video of the working prototype on YouTube, deaf people around the country have been writing on a daily basis. For mobile communication, deaf people now communicate by cell phone using text messages. Video is much better than text-messaging because it's faster and it's better at conveying emotion. Low data transmission rates on U.S. cellular networks have so far prevented real-time video transmission with enough frames per second that it could be used to transmit sign language.

Communication rates on United States cellular networks allow about one tenth of the data rates common in places such as Europe and Asia (sign language over cell phones is already possible in Sweden and Japan). The current version of MobileASL uses a standard video compression tool to stay within the data transmission limit. Future versions will incorporate custom tools to get better quality. The team developed a scheme to transmit the person's face and hands in high resolution, and the background in lower resolution. Now they are working on another feature that identifies when people are moving their hands, to reduce battery consumption and processing power when the person is not signing. Mobile video sign language won't be widely available until the service is provided through a commercial cell-phone manufacturer.

More information:

http://www.sciencedaily.com/releases/2008/08/080821164609.htm

http://mobileasl.cs.washington.edu/index.html

http://youtube.com/watch?v=FaE1PvJwI8E