Patent ID: 6332037
Filing Date: 2001-12-18
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. determining Eigenvalues for essentially the entire data image, said Eigenvalues being a major axis (.lambda..sub.11) and a minor axis (.lambda..sub.21) of a characteristic virtual ellipse, then calculating a first (I1) non-degenerate data image index element using the formula: ##EQU17##b. 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; andsaid major axis;and for each of said first and second data image parts independently determining Eigenvalues therefore, said Eigenvalues being a major axis (.lambda..sub.12) and a minor axis (.lambda..sub.22) for the first of said separate characteristic virtual ellipses, and major axis (.lambda..sub.13) and a minor axis (.lambda..sub.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: ##EQU18##c. concatenating said first, second and third non-degenerate data image index elements to provide said identifying data image index (I) by a selection from the group consisting of:I=I1 I2 I3;I=I1 I3 I2;I=I2 I1 I3;I=I2 I3 I1;I=I3 I1 I2; andI=I3 I2 I1.