A method is provided for rendering a color image with a plurality of
separations with a halftone process using a single screen. The screen is
comprised of a plurality of pixel locations with associated threshold
values and the image is comprised of a plurality of separation values.
The method includes the steps of rendering a first one of the plurality
of separations in accordance with the screen, wherein the plurality of
pixel locations are turned on or off at a given pixel location based on a
comparison of the image separation value at that pixel with the screen
threshold value. The rendering of the next color separation is made in
accordance with the rendering of the first separation and the screen,
wherein for constant image separation values, pixel locations are turned
on for the separation at pixel locations disposed in a highest available
luminance region having a lowest available threshold value. When
successive filling approaches the end portion of available threshold
values, overlap filling with earlier rendered color separations occurs
before the screen is completely filled.