| 摘要 |
PCT No. PCT/JP88/00675 Sec. 371 Date Mar. 6, 1989 Sec. 102(e) Date Mar. 6, 1989 PCT Filed Jul. 6, 1988 PCT Pub. No. WO89/00317 PCT Pub. Date Jan. 12, 1989.A pictorial image comprising pixels represented by a combination of density values in respect to first color components (R, G, B) is transformed to a pictorial image comprising pixels represented by combination of density values in respect to second color components (C, M, Y). In accordance with the first color modification method, an operation expressed as Q= alpha P+ beta is implemented to an original density value P using two correction coefficients alpha and beta determined in advance to determine a density value Q after transformation. In addition, in accordance with the second color modification method, density values after transformation are determined by the calculation of the k-th degree masking equation using the k-th degree masking coefficients. At this time, a color cube is defined with respect to the first color components. The color cube thus defined is divided into an n number of blocks. The k-th degree masking coefficients are defined every respective blocks. Then, calculation of the k-th degree masking equation is performed using the k-th degree masking coefficients defined with respect to blocks involving points indicative of original density values within the color cube. |
