A new optimal digital halftoning technique based on the discrete cosine transform

Digital halftoning is a technique to display a gray-level image with a bile vel device. Conventionally, most halftoning techniques are done in the spat ial domain. A new halftoning technique based on the discrete cosine transfo rm is proposed. The method chooses an optimal bilevel image to display the original gray-level image and minimize the weighted mean square error based on the discrete cosine transform domain. The simulation results indicate t hat our algorithm can produce very good halftoned images without false cont ours. (C) 2000 Elsevier Science B.V. All rights reserved.