Color halftoning using a conventional screen requires rotating the screen by different angles for different color planes to avoid Moiré patterns. With the Blue Noise Mask (BNM), which is a stochastic screen that produces visually pleasing blue noise, Moiré patterns are not produced and therefore screen angles are not required. We have developed several strategies to apply our masks to color planes as following:1. the Dot-on-Dot scheme, which uses the same mask on all color planes.2. the Shifting scheme, which uses shifted versions of same mask on different planes.3. the Inverting scheme, which applies one mask and its inverted version to two planes, with an optional adaptive algorithm for other planes.4. the Four Masks scheme, whereby four distinct masks are generated for each of the CMYK planes. These masks are anti-correlated in a mutually exclusive manner so that color dye is maximally dispersed.These schemes are applied to color images, and the results are studied in the CIELAB space based on human visual model. Comparisons against error diffusion results are also presented.
Qing Yu, Kevin J. Parker, Meng Yao, "Color Halftoning with Blue Noise Masks" in Proc. IS&T 4th Color and Imaging Conf., 1996, pp 77 - 79, https://doi.org/10.2352/CIC.1996.4.1.art00022