System and method for rendering printing traps with application of color transformations

摘要

A system and method for handling overprinting in generating a raster page for continuous tone or halftone printing. A color transformation is used to generate tints for each of the colorants for each of the colored shapes. When rendering a shape that is set for overprinting, the tints of colorant for each pixel is determined by comparing the colorant tints determined by the color transformation of the foreground shape with the colorant tints previously determined for the pixel according to the background. The pixel colorant tints are reset with the colorant tints of the foreground shape when the tints of the foreground shape are darker than the tints of the background. Where the tints of the foreground shape are lighter than the background, the background tints are left unchanged producing a transparency effect. The system and method are adaptable to colored shapes comprising a vignette. The system and method are also applicable to negative image production.