Patent ID: 7233696

Claim:
A method of characterizing an M-column by N-row array of image pixels, said method comprising: (1) reading the amplitudes of said pixels; (2) assigning column and row indices to said amplitudes; (3) organizing said amplitudes into segment amplitude sets for M columns and N rows; (4) organizing segment period sets for M columns and N rows (5) calculating mean value sets for said segment amplitude sets; (6) calculating standard deviation sets for said mean value sets; (7) using said mean value sets and said standard deviation sets to characterize said array of image pixels, and (8) determining registration errors through calculation of difference coefficients d(c) and d(r) defined by the following equations: D ( c )=[ Ma ( c,A )− Ma ( c,B )][ Da ( c,A )− Da ( c,B )][ Mt ( c,A )− Mt ( c,B )][ Dt ( c,A )− Dt ( c,B )] D ( r )=[ Ma ( r,A )− Ma ( r,B )][ Da ( r,A )− Da ( r,B )][ Mt ( r,A )− Mt ( r,B )][ Dt ( r,A )− Dt ( r,B )] where: Ma(c,X)=column amplitude mean axis function for image X, where “c” denotes a particular column Da(c,X)=column amplitude deviation axis function for image X, where “c” denotes a particular column Mt(c,X)=column period mean axis function for image X, where “c” denotes a particular column Dt(c,X)=column period deviation axis function for image X, where “c” denotes a particular column Ma(r,X)=row amplitude mean axis function for image X, where “r” denotes a particular row, Da(r,X)=row amplitude deviation axis function for image X, where “r” denotes a particular row, Mt(r,X)=row period mean axis function for image X, where “r” denotes a particular row, Dt(r,X)=row period deviation axis function for image X, where “r” denotes a particular row.