Method and circuit arrangement for simulating a multi-colored reproduction on a color monitor

Claim 1

An arrangement for isochromatic simulation of a multi-colored reproduction on a color monitor, comprising: (a) signal source means for outputting color separation values Y,M,C,K of a multi-colored reproduction; (b) transformer stage means connected to said signal source means for transformation of said color separation values Y,M,C,K into color monitor video drive values required for the isochromatic simulation; (c) a color monitor means connected to receive said video drive values; (d) said transformer stage means comprising (i) gradation stage means connected to said signal source means for changing the color separation values Y,M,C,K output by said signal source means according to a reproduction gradation curve dependent on the later to occur reproduction process; (ii) an arithmetic stage means for calculation of color value triads r,g,b for a supporting point network of a reproduction color space; (iii) a supporting value memory means connected to said arithmetic stage means for deposit of the calculated color value triads of the supporting point network; (iv) an interpolation stage means communicating with said gradation stage means, arithmetic stage means, and supporting value memory means for interpolation of color value triads r,g,b from color value triads r n ,b n , g n of said supporting point network dependent on altered color separation values Y', M', C' of the three chromatic color separations of the multi-colored reproduction; (v) logic stage means communicating with said interpolation stage means and gradation stage means for formation of corrected color value triads r', g', b' from the color value triads r,g,b and from color separation values K' of a black separation; (vi) linearization stage means connected to said logic stage means for generating linearized color value triads r v , g v , b v from the color value triads r,g,b according to the radiation density characteristics of the color monitor means; and (vii) analog-to-digital converter means communicating with the linearization stage means for generating video drive values r' v , g' v , b' v from the linearized color value triads r v , g v , b v .

Claim 7

A method for color equivalent simulation of a multicolor printing on a color monitor, wherein color separation values which represent colors of the multicolor printing to be printed on a print medium are converted into video drive values r v , g v , b v for the color monitor used to generate desired monitor colors which are color equivalents to the printed colors of the multicolor printing, comprising the steps of: (a) before the simulation; (i) linearizing non-linearities between radiation densities of the individual phosphors of the color monitor and nominal color values representing the desired monitor colors by determining for each triad of nominal color values, based upon said non-linearities, a corresponding triad of actual color values necessary to generate the desired monitor color; (ii) producing triads of color values r, g, b, converting said triads of the color values r, g, b into said video drive values r v , g v , b v and generating respective monitor colors on said color monitor; (iii) matching said generated monitor colors to corner colors of a print color space printed on the print medium by changing the triads of the color values r, g, b; (iv) measuring the triads of color values r, g, b obtained by the matching which are required for generating the monitor colors which are color equivalent to said corner colors of the print color space; (v) calculating for intermediate colors lying between said corner colors of the print color space from triads of the color separation values Y, M, C for the three chromatic color separations of the corresponding intermediate color triads of color values r, g, b needed to generate monitor colors which are color equivalents to said intermediate colors and taking into consideration a type of printing method used in the later to occur printing process for said multicolor printing; (vi) allocating to the triads of color separation values Y, M, C of the three chromatic color separations of the corner colors and intermediate colors of the print color space the corresponding measured and calculated triads of color values r, g, b to be converted into the color drive values instead of the allocated color separation values Y, M, C to generate monitor colors which are color equivalents to said corner and intermediate colors; and (b) during the simulation: (i) calling up the color separation values Y, M, C of the three chromatic color separations and the color separation values K for black separation of the multicolor printing to be simulated on the color monitor; (ii) modifying said color separation values Y, M, C of the multicolor printing according to a printing gradation used in the later to occur printing process for said multicolor printing; (iii) outputting the previously allocated triads of color values r, g, b instead of the modified color separation values Y', M', C' of the three chromatic color separations of said multicolor printing; (iv) combining said output triads of color values r, g, b and said modified color separation values K' of the black separation of the multicolor printing to obtain triads of corrected color values r', g', b'; and (v) converting said triads of corrected color values r', g', b' into said video drive values r v , g v , b v for controlling said color monitor.

Claim 8

A method for color equivalent simulation of a multicolor printing on a color monitor, wherein color separation values which represent colors of the multicolor printing to be printed on a print medium are converted into video drive values r v , g v , b v for the color monitor used to generate desired monitor colors which are color equivalents to the printed colors of the multicolor printing, comprising the steps of: (a) before the simulation; (i) linearizing non-linearities between radiation densities of the individual phosphors of the color monitor and nominal color values representing the desired monitor colors by determining for each triad of nominal color values, based upon said non-linearities, a corresponding triad of actual color values necessary to generate the desired monitor color; (ii) producing triads of color values r, g, b, converting said triads of the color values r, g, b into said video drive values r v , g v , b v and generating respective monitor colors on said color monitor; (iii) matching said generated monitor colors to corner colors of a print color space printed on the print medium by changing the triads of the color values r, g, b; (iv) measuring the triads of color values r, g, b obtained by the matching which are required for generating the monitor colors which are color equivalent to said corner colors of the print color space; (v) calculating for intermediate colors lying between said corner colors of the print color space from triads of the color separation values Y, M, C for the three chromatic color separations of the corresponding intermediate color triads of color values r, g, b needed to generate monitor colors which are color equivalents to said intermediate colors and taking into consideration a type of printing method used in the later to occur printing process for said multicolor printing; (vi) allocating to the triads of color separation values Y, M, C of the three chromatic color separations of the corner colors and intermediate colors of the print color space the corresponding measured and calculated triads of color values r, g, b to be converted into the color drive values instead of the allocated color separation values Y, M, C to generate monitor colors which are color equivalents to said corner and intermediate colors; and (b) during the simulation: (i) calling up the color separation values Y, M, C of the three chromatic color separations and the color separation values K for black separation of the multicolor printing to be simulated on the color monitor; (ii) modifying said color separation values Y, M, C of the multicolor printing according to a printing gradation used in the later to occur printing process for said multicolor printing; (iii) outputting the previously allocated triads of color values r, g, b instead of the modified color separation values Y', M', C' of the three chromatic color separations of said multicolor printing; (iv) combining said output triads of color values r, g, b and said modified color separation values K' of the black separation of the multicolor printing to obtain triads of corrected color values r', g', b'; and (v) converting said triads of corrected color values r', g', b' into said video drive values r v , g v , b v for controlling said color monitor.

Claim 19

An apparatus for color equivalent simulation of a multicolor printing on a color monitor, wherein color separation values which represent colors of the multicolor printing to be printed on a print medium are converted into video drive values r v , b v , b v for the color monitor used to generate desired monitor colors which are color equivalents to the printed colors of the multicolor printing comprising: (a) means for performing processing before the simulation, including: (i) means for linearizing non-linearities between radiation densities of the individual phorphors of the color monitor and nominal color values representing the desired monitor colors by determining for each triad of nominal color values, based upon said non-linearities, a corresponding triad of actual color values necessary to generate the desired monitor color; (ii) means for producing triads of color values r, g, b, converting said triads of the color values r, g, b into said video drive values r v , g v , b v , and generating respective monitor colors on said color monitor; (iii) means for matching said generated monitor colors to corner colors of a print color space printed on the print medium by changing the triads of the color values r, g, b; (iv) means for measuring the triads of color values r, g, b obtained by the matching which are required for generating the monitor colors which are color equivalent to said corner colors of the print color space; (v) means for calculating for intermediate colors lying between said corner colors of the print color space from triads of the color separation values Y, M, C for the three chromatic color separations of the corresponding intermediate colors triads of color values r, g, b needed to generate monitor colors which are color equivalents to said intermediate colors and taking into consideration a type of printing method used in the later to occur printing process for said multicolor printing; (vi) means for allocating to the triads of color separation values Y, M, C of the three chromatic color separations of the corner colors and intermediate colors of the print color space the corresponding measured and calculated triads of color values r, g, b to be converted into the color drive values instead of the allocated color separation values Y, M, C to generate monitor colors which are color equivalents to said corner and intermediate colors; and (b) means for processing during the simulation, including: (i) means for calling up the color separation values Y, M, C of the three chromatic color separations and the color separation values K for black separation of the multicolor printing to be simulated on the color monitor; (ii) means for modifying said color separation values Y, M, C of the multicolor printing according to a printing gradation used in the later to occur printing process for said multicolor printing; (iii) means for outputting the previously allocated triads of color values r, g, b instead of the modified color separation values Y', M', C' of the three chromatic color separations of said multicolor printing; (iv) means for combining said output triads of color values r, g, b and said modified color separation values K' of the black separation of the multicolor printing to obtain triads of corrected color values r', g', b'; and (v) converting said triads of corrected color values r', g', b' into said video drive values r v , g v , b v for controlling said color monitor.

Claim 20

An apparatus for color equivalent simulation of a multicolor printing on a color monitor, wherein color separation values which represent colors of the multicolor printing to be printed on a print medium are converted into video drive values r v , b v , b v for the color monitor used to generate desired monitor colors which are color equivalents to the printed colors of the multicolor printing comprising: (a) means for performing processing before the simulation, including: (i) means for linearizing non-linearities between radiation densities of the individual phorphors of the color monitor and nominal color values representing the desired monitor colors by determining for each triad of nominal color values, based upon said non-linearities, a corresponding triad of actual color values necessary to generate the desired monitor color; (ii) means for producing triads of color values r, g, b, converting said triads of the color values r, g, b into said video drive values r v , g v , b v , and generating respective monitor colors on said color monitor; (iii) means for matching said generated monitor colors to corner colors of a print color space printed on the print medium by changing the triads of the color values r, g, b; (iv) means for measuring the triads of color values r, g, b obtained by the matching which are required for generating the monitor colors which are color equivalent to said corner colors of the print color space; (v) means for calculating for intermediate colors lying between said corner colors of the print color space from triads of the color separation values Y, M, C for the three chromatic color separations of the corresponding intermediate colors triads of color values r, g, b needed to generate monitor colors which are color equivalents to said intermediate colors and taking into consideration a type of printing method used in the later to occur printing process for said multicolor printing; (vi) means for allocating to the triads of color separation values Y, M, C of the three chromatic color separations of the corner colors and intermediate colors of the print color space the corresponding measured and calculated triads of color values r, g, b to be converted into the color drive values instead of the allocated color separation values Y, M, C to generate monitor colors which are color equivalents to said corner and intermediate colors; and (b) means for processing during the simulation, including: (i) means for calling up the color separation values Y, M, C of the three chromatic color separations and the color separation values K for black separation of the multicolor printing to be simulated on the color monitor; (ii) means for modifying said color separation values Y, M, C of the multicolor printing according to a printing gradation used in the later to occur printing process for said multicolor printing; (iii) means for outputting the previously allocated triads of color values r, g, b instead of the modified color separation values Y', M', C' of the three chromatic color separations of said multicolor printing; (iv) means for combining said output triads of color values r, g, b and said modified color separation values K' of the black separation of the multicolor printing to obtain triads of corrected color values r', g', b'; and (v) converting said triads of corrected color values r', g', b' into said video drive values r v , g v , b v for controlling said color monitor.