Minimal Interaction Touchless Text Input with Head Movements and Stereo Vision

Many modern interfaces for human-computer interaction are based on some kind of visual system and offer touchless and convenient medium for communication for the user. These non-contact interfaces predominantly limit their operations to gesture recognition or a pointer manipulation in a graphical user interface. The problem of typing in most cases is omitted since touchless interfaces are not designed for text entry purposes. There is, however, a great number of people who suffer from some form of disability. They are unable to use standard input devices ( mouse and keyboard) or modern touchless interfaces. For those physically challenged people a minimal interaction interface for text entry operated with head movements is proposed in the paper. It is based on processing video streams from a stereo webcam, uses only directional head movements and a dictionary support.