Patent ID: 6018687
Filing Date: 2000-01-25
Classification: B26D,B65H,Y10T

Abstract:
A method for determining a suitable lateral position of a scanner relative to an image printed with ink on a web for use with a cutoff control system, the scanner having a field of view and producing an output signal representative of the portion of the image within the field of view, said method comprising the steps of:storing a reference array of digital prepress data in a format representative of the ink and the location of the ink in the printed image;transforming the reference array into a transformed array in a format representative of the output signal of the scanner;autocorrelating a segment of said transformed array to produce an autocorrelation array having at least one mathematical peak, said segment representative of a longitudinal portion of the image;cross-correlating said segment of said transformed array with a plurality of neighboring segments of said transformed array, each of said neighboring segments representative of a longitudinal portion of the image, thereby producing a cross-correlation array having at least one mathematical peak;determining any peaks in the cross-correlation array and autocorrelation array above a first predetermined threshold; anddetermining whether the cross-correlation array and the autocorrelation array each contain a single adjacent peak, and if so, determining the portion of the image corresponding to said peaks.