1. A method of performing vision processing comprising: producing a depth map of a scene proximate a platform, wherein the depth map is based on an assumed ground plane; identifying an actual ground plane using the depth map; and compensating the depth map for differences between the assumed ground plane and the actual ground plane thereby resulting in a compensated depth map including a collection of 3-D points; and comparing the depth map to a plurality of templates to identify a match between the depth map and at least one template, wherein the comparing step includes determining a difference between each pixel in the depth map and each similarly positioned pixel in a template, and determining that a pixel is a match if the difference at each pixel is less than a predefined amount.