Method for performing transformations of color data

Method for computer-aided execution of transformations of color data from a source color space to a target color space using a transformation rule TRV, wherein

• the source color space comprises n colors, which are present in combinations of color components q(1) to q(n) in each point to be represented,
• the target color space comprises m values that can be combined to form combinations of components z(1) to z(m),
• combinations of them components of the target color space are assigned to at least some combinations of the n colors of the source color space via the transformation rule TRV,
• characterized by the following steps:
• a) for a combination KB of the n colors of the source color space with color components qKB (1) to qKB (n) for which no combination of the m components zKB (1) to zKB (m) of the target color space is assigned via the TRV, select a color i of the combination KB which has a color component FA=qKB (i)>0 and for which the following conditions apply:
• i) the remaining combination of color components qKB (j not equal to i) without the component of color i is assigned a combination of the target color space with components z(1)i, z(2)i, . . . , z(m)i, and
• ii) two further, with one exception mutually identical combinations of color components q(1) to q(n) exist, to each of which a combination of components z(1) to z(m) is assigned and wherein the two combinations of color components q(1)1 to q(n)1 and q(1)2 to q(n)2 differ only in that the color component q(i) of color i in the one q(i)1=FA>0 and in the other q(i)2=0, so that
• 1) The combination q(1)1 to q(n)1 with color component q(i)1=FA is assigned a corresponding combination of the components z(1)1, z(2)1, . . . , z(m)1 of the m values of the target color space, which forms the color data set Z1, and
• 2) the combination q(1)2 to q(n)2 with color component q(i)2=0 is assigned a corresponding combination of the components z(1)2, z(2)2, . . . , z(m)2 of the m values of the target color space, which forms the color data set Z2,
• iii) Calculating the ratios V(1)i, V(2)i, . . . , V(m)i of each component z(1)1, z(2)1, . . . , z(m)1 of the m values of the color data set Z1 to the respective component z(1)2, z(2)2, . . . , z(m)2 of the m values of the color data set Z2, which form a set of factors V(1)i=z(1)1/z(1)2, V(2)i=z(2)/z(2)12, . . . , V(m)i=z(m)/z(m)12,
• b) Applying the factors V(1)i, V(2)i, . . . , V(m)i for transformations of combinations KB of colors of the source color space with n colors, which contain the color component FA of color i, but for which the color component q(i)=0 is set for the transformation, into the target color space with m components by multiplying the z(1)i, z(2)i, . . . , z(m) of the target color space resulting from the transformation by the respective factors V(1), V(2), . . . , V(m), z(m)i of the target color space are multiplied by the respective factors V(1)i, V(2)i, . . . , V(m)i.