Abstract: Physical objects, including still and moving images, are transformed into more compact forms for identification and other purposes using a method unrelated to existing image-matching systems which rely on feature extraction. An auxiliary construct, preferably a warp grid, is associated with an image, and a series of transformations are imposed to generate a unique visual key for identification, comparisons, and other operations. Search methods are also disclosed for matching an unknown image to one previously represented in a visual key database. Broadly, a preferred search method sequentially examines candidate database images for their closeness of match in a sequential order determined by their a priori match probability. Thus, the most likely match candidate is examined first, the next most likely second, and so forth.