Efficient Communication by Breathing

The arithmetic-coding-based communication system, Dasher, can be driven by a one-dimensional continuous signal. A belt-mounted breath-mouse, delivering a signal related to lung volume, enables a user to communicate by breath alone. With practice, an expert user can write English at 15 words per minute. Dasher is a communication system based on a beautiful idea from information theory called arithmetic coding (Witten et al., 1987; MacKay, 2003, Chapter 6). Arithmetic coding is an optimal method for text-compression using a language model. By turning arithmetic coding on its head, we obtain an optimal method for text-generation. We view a person's gestures as a source of information, and the sentences they wish to communicate as the sink of information. Good interface design maximizes the number of bits per second that are conveyed from the user into text. Poor interfaces waste the user's time either by failing to extract all the bits that the user could easily generate, or by ...

• Type: Conference
• Year: 2004
• Where: DSMML
• Authors: Tom Shorrock, David MacKay, Chris Ball
• Keywords: Arithmetic Coding, Dasher, DSMML 2004, Machine Learning, Optimal Method