Apparatus and method for producing color corrected reproduction of colored original images

Claim 1

A method of operating a processing unit for producing output signals representative of agent color densities of coloring agents such as process inks or toners, to be used in producing a color-corrected image unit of an initial image unit using the coloring agents, the processing unit including memory means for storing selected data, the coloring agents presenting respective agent colors, said method comprising the steps of: (a) entering input signals into the processing unit which are respectively representative of color readings of the image unit to be finally produced using said coloring agents; (b) determining initial color densities that correspond relatively to said color readings entered into the processing units; (c) retrieving from the memory means previously stored data representative of respective contribution factors corresponding to the contribution to each of the agent colors from each of the other coloring agents; (d) retrieving from the memory means previously stored data representative of certain predetermined nonlinearity correction factors which are representative of the particular coloring agents to be used in producing said image unit; (e) calculating in said processing unit, for each agent color of a respective coloring agent, a contribution amount to each of the other agent colors as a function of the effect thereon of the respective initial color density, contribution factor, and correction factor; (f) calculating in said processing unit, for each agent color, a final agent color density as a function of its corresponding initial density and the contribution amounts from the other coloring agents; and (g) producing output signals representative of each of said final agent color densities.

Claim 2

A method of operating a processing unit for producing output signals representative of agent color densities of coloring agents such as process inks or toners, to be used in producing a color-corrected image unit of an initial image unit using the coloring agents, the processing unit including memory means for storing selected data, the coloring agents presenting respective agent colors, said method comprising the steps of: (a) entering input signals into the processing unit which are respectively representative of color readings of the image unit to be finally produced using said coloring agents; (b) determining initial color densities that correspond relatively to said color readings entered into the processing units; (c) retrieving from the memory means previously stored data representative of respective contribution factors corresponding to the contribution to each of the agent colors from each of the other coloring agents; (d) retrieving from the memory means previously stored data representative of certain predetermined nonlinearity correction factors which are representative of the particular coloring agents to be used in producing said image unit; (e) calculating in said processing unit, for each agent color of a respective coloring agent, a contribution amount to each of the other agent colors as a function of the effect thereon of the respective initial color density, contribution factor, and correction factor; (f) calculating in said processing unit, for each agent color, a final agent color density as a function of its corresponding initial density and the contribution amounts from the other coloring agents; and (g) producing output signals representative of each of said final agent color densities.

Claim 13

An apparatus for producing output signals representative of the agent color densities of coloring agents such as process inks or toners, to be used in producing a color-corrected image unit of an initial image unit using the coloring agents, said apparatus comprising: a processing unit, having memory means for storing selected data therein, for receiving input signals and for producing output signals in response thereto; means for entering input signals into the processing unit which are respectively representative of color readings of the image to be finally produced using the coloring agents; said processing unit including means for determining initial agent color densities that correspond relatively to said color readings entered into said processing unit, means for retrieving from said memory means previously stored data representative of respective contribution factors corresponding to the contribution to each of the agent colors from each of the other coloring agents, means for retrieving from the memory means previously stored data representative of certain predetermined nonlinearity correction factors which are representative of the particular coloring agents to be used in producing said image unit, means for calculating, for each agent color of a respective coloring agent, a contribution amount to each of the other coloring agents as a function of the effected thereon of the respective initial color density, contribution factor, and correction factor; means for calculating, for each agent color, a final agent color density as a function of its corresponding initial density and the contribution amounts from the other coloring agents, and means for producing output signals representative of each of said final agent color densities.

Claim 14

An apparatus for producing output signals representative of the agent color densities of coloring agents such as process inks or toners, to be used in producing a color-corrected image unit of an initial image unit using the coloring agents, said apparatus comprising: a processing unit, having memory means for storing selected data therein, for receiving input signals and for producing output signals in response thereto; means for entering input signals into the processing unit which are respectively representative of color readings of the image to be finally produced using the coloring agents; said processing unit including means for determining initial agent color densities that correspond relatively to said color readings entered into said processing unit, means for retrieving from said memory means previously stored data representative of respective contribution factors corresponding to the contribution to each of the agent colors from each of the other coloring agents, means for retrieving from the memory means previously stored data representative of certain predetermined nonlinearity correction factors which are representative of the particular coloring agents to be used in producing said image unit, means for calculating, for each agent color of a respective coloring agent, a contribution amount to each of the other coloring agents as a function of the effected thereon of the respective initial color density, contribution factor, and correction factor; means for calculating, for each agent color, a final agent color density as a function of its corresponding initial density and the contribution amounts from the other coloring agents, and means for producing output signals representative of each of said final agent color densities.