An article of manufacture comprising a computer-readable medium having stored thereon instructions adapted to be executed by a processor, the instructions which, when executed, define a series of steps for identifying a silhouette contour of an object that is depicted within a first image, the first image comprised of a plurality of pixels with each pixel containing a light intensity value that describes either the object or a background, the silhouette contour of the object comprised of a group of pixels which describe one contour of the object's shape, the steps comprising:
- a. identifying within the first image a set of pixels which describe the object by comparing the light intensity value of the pixels of the first image against the light intensity values of a second image, separate from the first image, which depicts the background but not the object;
- b. locating one pixel which does not describe the object;
- c. moving sequentially through the light intensity values of the pixels of the first image to locate a first pixel which describes the object, that pixel being a first pixel in a cluster of pixels which describe the object;
- and
- d. identifying from the point of said first pixel those other pixels of the cluster which lie on the perimeter of the cluster.