1. A method for segmenting an object within an image in a tracking device, comprising: placing a processing window within the image that is centered about a centroid of the object, wherein the processing window comprises a subarea of the image, and dimensions and position of the processing window are based on priori information regarding size of a pre-screener box for the object and location of a centroid of the object based on input from an operator; extracting, in the tracking device, from the subarea of the image within the processing window, an edge image containing a first set of pixels from the object; generating, in the tracking device, a second set of pixels from the first set of pixels using mathematical morphology to fill in pixels of the edge image; identifying, in the tracking device, a segment corresponding to the object from the second set of pixels; and autonomously tracking the object with a pre-screener in the tracking device and adjusting the size of the processing window to prevent a signature of the object from outgrowing the processing window to permit subsequent morphological processing of the object, wherein a size of the signature changes in accordance with a distance between the pre-screener and the object.