Patent ID: 6868178

Claim:
A method for processing image data, comprising the steps of: scanning at least one section of a form raster-like; converting said scanned form into a digital image comprising picture elements, a color of each and every picture element being presented according to the HSB color presentation at hue H, saturation S and brightness B; determining, from a membership function zUBB via said brightness or from a membership zUBS via said saturation, in conformity with a fuzzy technique, memberships ZUBB and ZUBS of said color of each and every picture element in a first color class UB; determining, from a membership function zSBB via said brightness B, a membership function zSFS via said saturation S, or from a membership function zSFH via said hue H, memberships ZSFB, ZSFS and ZSFH of said color of each and every picture element in a second color class SF; determining, from a membership function zBFB via the brightness B, a membership function zBFS via the saturation S, or from a membership function zBFH via the hue H, memberships ZBFB, ZBFS an ZBFH of said color of each and every picture element in at least one third color class BF; determining minimum values UB MIN=( ZUBB, ZUBS ), SF MIN=( ZSFB, ZSFS, ZSFH ), and BF MIN=( ZBFB, ZBFS, ZBFH ) of said memberships ZUBB, ZUBS, ZSFB, ZSFS, ZSFH, ZBFB, ZBFS, ZBFH in respective color classes UB, SF, BF; determining a maximum value M among said minimum values UBMIN, SFMIN, BFMIN; allocating a respective color as well as picture elements belonging to this color to a color class UB, SF, BF that belongs to said maximum value M; and allocating, depending on identified said color class UB, SF, BF, a gray scale value GW to a respective picture element.