2. A method according to claim 1 wherein performing a plurality of element-wise comparisons comprises: creating a hash value for a graphic element based on attribute values of the graphic element; associating the graphic element with the hash value; and performing an element-wise comparison between a first graphic element and a second graphic element if the first and second graphic elements are associated with the same hash value.
1. A method for comparing first and second documents, the first and second documents containing corresponding first and second pluralities of graphic elements, the method comprising: associating a unique identifier with each graphic element of the first plurality of graphic elements; comparing each one of the second plurality of graphic elements with the first plurality of graphic elements; associating a unique identifier with a graphic element of the second plurality of graphic elements if the graphic element is not sufficiently similar to any graphic element of the first plurality of graphic elements; associating an existing identifier with the graphic element of the second plurality of graphic elements if the graphic element is sufficiently similar to the first graphic element of the first plurality of graphic elements wherein the first graphic element is associated with the existing identifier; organizing the unique identifiers into a first list and a second list, entries of the first list corresponding to a display order of the graphic elements from the first document, and entries of the second list corresponding to a display order of the graphic elements from the second document; and wherein comparing the second plurality of graphic elements with the first plurality of graphic elements comprises performing a plurality of element-wise comparisons based on a plurality of similarity rules.