Patent ID: 7791763
Filing Date: 2010-09-07
Classification: H04N

Abstract:
1. A color separation method including processing for converting an image signal into a signal of a color material used in a printing apparatus, the processing converting the image signal into a color material signal containing a color material value of a dark color material and a color material value of a light color material, the method comprising: a step of producing a density characteristics map including cells of M rows×N columns showing a density of each of the dark color material and the light color material; a step of producing a color material amount characteristics map including cells of M rows×N columns showing a color material amount of each of the dark color material and the light color material; a step of searching a cell of a target equal density from the density characteristics map and counting a row and a column of the searched cell of the target equal density in the density characteristics map; a step of searching a cell of a target equal color material amount from the color material amount characteristics map and counting a row and a column of the searched cell of the target equal color material amount in the color material amount characteristics map; a step of searching the cell in a certain direction in a certain row and determining whether the counted columns between the searched cell of the target equal density and the searched cell of the target equal color material amount correspond with each other; a step of setting the color material amount of each of the dark color material and the light color material shown in the searched cell where the counted columns between the searched cell of the target equal density and the searched cell of the target equal color material amount correspond with each other, as a color material amount of each of the dark color material and the light color material, in a case where the counted columns between the searched cell of the target equal density and the searched cell of the target equal color material amount correspond with each other; and a step of setting the color material amount of each of the dark color material and the light color material shown in the searched cell on the color material amount characteristics map of the target equal color material amount as a color material amount of each of the dark color material and the light color material, in a case where the counted columns between the searched cell of the target equal density and the searched cell of the target equal color material amount do not correspond with each other, when a color material amount in the cell on the color material amount characteristics map exceeds the target equal color material amount.