Image edge location estimate based on the image centroid slope

A technique is developed for estimating the leading edge location of an imaged target based on the target's centroid and its slope as the raster is scanned across the target's image. Since the estimate involves more pixels than the standard edge algorithms, the estimate should be less noisy. without additional filtering. The algorithm is easily implemented in a pipe-line process so that the leading edge location can be determined as the video is being read off the focal plane array with minimum processing delay. This algorithm can be shown to be a generalization of the standard biased centroid;rack algorithm. However, while the biased centroid algorithm requires a priori knowledge of the imaged target shape in order to determine the proper bias, this algorithm estimates the shape dependent factors in real time without any a priori knowledge.