1. A camera-based touch system comprising: at least two image sensors associated with a touch surface and having overlapping fields of view encompassing said touch surface, said at least two image sensors acquiring images of said touch surface from different vantages; and processing structure processing pixel subsets of the images acquired by said at least two image sensors, pixel data of each pixel subset being processed to determine the existence of a pointer by calculating a median location of the pointer, said processing structure using the calculated median locations to triangulate the location of the pointer relative to said touch surface.