Fast and independent access to map directions for people who are blind

摘要

This article presents an automatic approach, complete with a prototype system, to supporting fast and independent access to online maps for local navigation by people with visual impairment. With user-inputted start and end addresses from a keyboard, the approach first queries MapQuest (www. mapquest.com) for obtaining the walking directions and the corresponding map image. Then, it automatically converts the obtained information in a form that can be reproduced immediately through a tactile printer, and subsequently generates an SVG (Scalable Vector Graphics) file, which associates textual descriptions of the directions with a recreated tactile map. The tactile hard copy can be placed on a touch-pad which is connected to a computer. With the generated SVG file opened in the computer, a user can explore the tactile map by hands, receiving instant audio feedback of the directions by pressing certain regions with special tactile patterns. This approach supports instant queries of walking directions without requiring tedious manual conversion by a sighted professional. The audio-tactile patterns, the adaptive representation scheme and the blind-friendly user interface are specifically designed for the visually-impaired users. Results from experimental evaluation based on a group of users with visual impairment suggest that the proposed approach is effective for providing blind computer users with independent access to geographic directions.