Patent ID: 8587829

Claim:
A method of converting colors of image data capable of producing a print of standard densities with a printing press set to standard density conditions and generating a print of desired designated densities with the printing press set to the standard density conditions, comprising the steps of: generating a standard density print profile capable of producing the print of the standard densities with the printing press set to the standard density conditions; generating a designated density print profile capable of producing the print of the designated densities with the printing press when the printing press is set to designated density conditions; and converting the colors of the image data using the standard density print profile and the designated density print profile, wherein the designated density print profile is used as an input profile, the standard density print profile is used as an output profile, and the colors of the image data are converted using the input profile and the output profile, wherein the step of generating the standard density print profile comprises the steps of: generating a standard density color chart with the printing press set to the standard density conditions; measuring the standard density color chart to determine standard measured values; and generating the standard density print profile based on image data for generating the standard density color chart and the standard measured values, and wherein the step of generating the designated density print profile comprises the steps of: changing the densities of color materials for producing the print individually by given amounts; generating a changed density color chart with the printing press set to changing density conditions in which the densities of other color materials than the color materials whose densities are changed are secured to the standard density conditions; measuring the changed density color chart to determine changed measured values; adjusting the standard measured values with the differences between the standard measured values and the changed measured values for the color materials to which desired designated densities are set; and generating the designated density print profile based on the image data for generating the standard density color chart and the adjusted standard measured values.