An application of fuzzy set theory for an electronic video camera image stabilizer

An electronic video camera image stabilizer has been developed which eliminates a substantial part of the image instability caused by the involuntary movement of camera holders. For the discrimination between image movement caused by unstable hand-holding and that of moving objects, fuzzy set theory is applied through the following process: 1) dividing the image taken by the camera into four regions, 2) providing two signals to discriminate between the causes of image instability, 3) evaluating these two discriminating signals after they are transformed into reliability values by membership functions, and 4) tuning the membership functions using a simplex method. This image stabilizer has been incorporated into a new compact video camera, and its substantially improved field performance has been confirmed