Color error-diffusion halftoning

In color halftoning, the application of grayscale error-diffusion methods to the individual colorant planes fails to exploit the human visual system (HVS) response to color noise. Ideally, the quantization error must be diffused to frequencies and colors, to which the HVS is least sensitive. Furthermore, it is desirable for the color quantization to take the colorant vector selected as the output color is perceptually the closest to the color vector being quantized. This paper discusses each of the above two design principles of color error diffusion that differentiate it from grayscale error diffusion.