Patent ID: 8171002
Filing Date: 2012-05-01
Classification: G06F,Y10S

Abstract:
1. A computer-implemented method for generating a plurality of signatures associated with a document, the method comprising: receiving a document comprising a plurality of characters; normalizing the document to remove non-informative characters from the plurality of characters; calculating a score for each informative character of the plurality of characters based on an occurrence frequency and distribution in the document; ranking each informative character of the plurality of characters based on the calculated score; selecting, from the ranked informative characters, character occurrences; and generating a signature for each selected character occurrence, wherein said score for each informative character is proportional to a first quantity divided by a second quantity, further wherein the first quantity comprises a position of a last occurrence of the informative character in the document minus a position of a first occurrence of the informative character in the document, and further wherein the second quantity comprises a square root of a sum of squares of differences in positions between adjacent occurrences of the informative character in the document.