Tracking Targets in FLIR Images by Region Template Correlation

This paper deals with the problem of providing missile guidance information by tracking a target object from a sequence of image frames captured from a forward looking in-frared (FLIR) camera mounted inside a missile moving directly towards the target. Many conventional image based trackers trace key reference points over an image sequence using simple correlation processes. However, the presence of noise and the magniication of image features as the camera approaches the object may cause a tracked point to drift. An alternative technique is to track regions formed by image segmentation. Segmen-tation is the process of partitioning image pixels into regions of homogeneous intensity levels, for example. However, the diiculty of tracking target regions in a noisy scene, typical of FLIR missile guiding systems, is that regions become divided and therefore there may be little correlation between regions in one frame and the next. This paper introduces a new method that provides a robust solution to the problem of tracking target regions. By acquiring a region template of the target in one frame, the target may be located in a future frame by employing a novel method of performing correlation of the template with a segmented image. For the current design, the target template is acquired manually in the initial frame. In subsequent frames, owing to target magniication, the template is updated automatically after the target has been detected. This new technique produces signiicant reductions in drift rate compared to a conventional point correlation tracker. Results acquired for real FLIR images obtained from an aircraft are presented.