摘要 |
PCT No. PCT/DE94/01182 Sec. 371 Date Sep. 4, 1996 Sec. 102(e) Date Sep. 4, 1996 PCT Filed Oct. 7, 1996 PCT Pub. No. WO95/10914 PCT Pub. Date Apr. 20, 1995A method and an apparatus for the conversion of color values of a first color space into color separation values of a printing color space characteristic of a printing process in apparatus and systems for color image processing. For the purpose of exact adaptation of the color separation values [C, M, Y, K] of the printing color space to the respective printing process, the functionally allocated color separation values [C, M, Y, K] are first approximately analytically calculated from the color values [L*, a*, b*] of the first color space as a printing table [C, M, Y, K=f(L*, a*, b*)], taking the printing colors of the respective printing color space of the later printing process, the colorimetric properties of the printing material employed later, and the printing process parameters into consideration. Subsequently, the calculated printing table [C, M, Y, K=f(L*, a*, b*)] is corrected by a color value calibration correction values [dL*, da*, db*] are calculated by comparison of the color values [L*(v), a*(v), b*(v)] of the first color space characteristic of the colors of a test table to the colorimetrically measured color values [L*(m), a*(m), b*(m)] of the corresponding colors of the test table produced as a proof, and the table values of the printing table [C, M, Y, K=f(L*, a*, b)] are corrected by the correction values [dL*, da*, db*].
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