A halftoning process includes: receiving CMYK input pixel data in terms of continuous tone input data values for cyan, magenta, yellow, and black colors converting the CMYK input pixel data to modified CMYKRGB* pixel data that define the input pixel in terms of error-adjusted continuous tone data values quantizing the modified CMYKRGB* pixel data to derive intermediate output CMYKRGB pixel data in which the cyan, magenta, yellow, black, red, green, and blue colors are each defined by either a first quantized value that represents no color or a second quantized pixel value that represents full color converting the intermediate output CMYKRGB pixel data to CMYK output data.