1. A method comprising: identifying a collection of computer-readable objects comprising input images; identifying a collection of one or more computer-readable instances of individual style sheets, wherein at least one of the individual style sheets comprises a statement referring to at least one of the input images; using the collection of one or more computer-readable instances of individual style sheets to determine a set of referenced images; assembling the determined set of the referenced images into a tiled image; and modifying at least a portion of at least one of the individual style sheets to generate at least one modified style sheet that references the tiled image.