T. Zeggel et O. Bryngdahl, Relation between grayvalue and noise frequencies in two- and three-level digital halftoning, OPT COMMUN, 164(1-3), 1999, pp. 13-18
In digital halftoning a close relationship exists between the local grayval
ues in the input image and the spatial frequencies of the quantization nois
e of the quantized image. Halftoning algorithms usually reproduce low frequ
encies well by introducing quantization noise of higher frequencies. We pre
sent and discuss a simple model for the relationship between grayvalue and
quantization noise frequencies. Optimization experiments with two and three
quantization levels are presented. (C) 1999 Elsevier Science B.V. All righ
ts reserved.