| 摘要 |
A digital color printing method and system is described which automatically detects when a black object is commanded to be printed, and changes the composition of the black color depending on the presence or absence of non-black colorants in the background color at the position on the page at which the edge of the black object is commanded to be printed. A single-color black object which is commanded to be printed at a position in which there is a previously rendered color background which contains non-black colorants will automatically have the composition of its black color changed from single-color black to process black composed of black plus non-black colorants such as cyan, magenta, and yellow. Conversely, a process black object which is commanded to be printed at a position in which the background does not contain non-black colorants will automatically have the composition of the black changed from process black to single-color black. For many printing systems the resulting prints exhibit fewer visual defects. Black objects printed on top of a color field are printed as process black and thereby exhibit a greater density and gloss and show fewer problems caused by the misregistration of separations or other printer defects, such as white fringes around the black objects. Conversely, black objects not on a color background are printed as single-color black objects and therefore do not exhibit objectionable process black problems such as color fringing, excessive colorant, and excessive gloss contrast with the background. <IMAGE> |
