Patent ID: 6625311
Filing Date: 2003-09-23
Classification: G06F,G06K

Abstract:
A method of providing an identifying data image index (I) for a two dimensional data image consisting of a multiplicity of pixels, said method comprising the steps of:a. applying a pixel pre-selection criteria to eliminate pixels not associated with image feature edges; b. determining Eigenvalues for essentially the entire remaining data image, said Eigenvalues being a major axis (&lgr;11) and a minor axis (&lgr;21) of a characteristic virtual ellipse, then calculating a first (I1) non-degenerate data image index element using the formula: I1=(Î»11-Î»21)2Î»11+Î»21c. dividing said essentially entire two dimensional data image into first and second data image parts about an axis selected from the group consisting of: said minor axis; said major axis; and an axis intermediate thereto; â€ƒand for at least one of said first and second data image parts independently determining Eigenvalues therefore, said Eigenvalues being a major axis (&lgr;12) and a minor axis (&lgr;22) for the first of said separate characteristic virtual ellipses, and major axis (&lgr;13) and a minor axis (&lgr;23) for the second of said separate characteristic virtual ellipses, and then calculating second (I2) and third (I3) non-degenerate data image index elements using the formulas: I2=(Î»12-Î»22)2Î»12+Î»22&it;â€ƒ&it;I3=(Î»13-Î»23)2Î»13+Î»23d. concatenating at least two of said determined first, second and third non-degenerate data image index elements in any functional permuted order to provide said identifying data image index (I).