A Communication Aid and Computer Input System Using Only the Human Eye

摘要

A communication aid using only the human eye is proposed. A set of candidate characters is displayed on a relatively small computer screen and a light head-mounted display (HMD) that is attached to glasses worn by the user. When the user looks at a candidate character with the left eye, an image of the right eye is taken with a small and light web camera that also is mounted on the glasses. The proposed system can select one character out of 81 characters, with two layers of 9 by 9 character candidate screen images. There is also another selection image including control keys and frequently used sentences. By using image matching between a previously acquired template image for each candidate character and the currently acquired image, the proposed system can determine which of the candidate characters has been selected. By the combined use of blinking and fixed gaze, the proposed system can determine the user-selected key among the candidates. The blink detection method employs a morphologic filter to avoid erroneous pupil detection due to eyebrows and shadows. Thus the user can input sentences. The user can also edit the sentences, which are then read by a text-to-speech (TTS) software tool. Thus the system helps handicapped and disabled persons without voice to communicate with others, because the only function required for conversation is the human eye. In addition, the proposed system can be used as an input system for wearable computing systems. Test results obtained with 6 nondisabled persons showed that the proposed system worked at an acceptable speed of about 1.5 second per character.