Stable tracking point extraction for infrared extended target based on contour smoothing and minimal inscribed circle

An approach is proposed to reduce the tracking jitter of the extended target in boost phase for plume tracker in a photoelectric acquis- ition, tracking, and pointing system. The characteristics of the vehicle im- aging are analyzed and the causes of jitters are identified. The target moving direction and its principal axis are combined to calculate the opti- mal frontal direction. A contour smoothing method based on the chord-arc ratio filtering is introduced to obtain a preliminary extraction point with lower jitters. Then a fine tracking point extraction method based on the minimal inscribed circle of contour after filtering is presented. Experimental results confirm that the proposed method significantly