1. A method of processing a pixel map representation of a document, comprising the steps of: a) obtaining a set of image data signals which represent light intensity in a portion of a digital image; b) creating a selector plane from said image data signals which separates said signals into subsets; c) creating a first image plane using said selector plane and said image data signals, wherein said first image plane contains a first subset of image data signals; d) creating a second image plane using said selector plane and said image data signals, wherein said second image plane contains a second subset of image data signals; and e) processing at least one of said first image plane and said second image plane based upon data contained in said selector plane.