Preserving features in multilevel halftones

Conventional threshold decomposition (TD) based multilevel halftoning algorithms decompose an input image into layers, halftone them sequentially with a binary halftoning algorithm, and combine their binary halftones to produce the final multilevel halftone. When these algorithms are exploited to produce multilevel halftones, bright spatial features are generally difficult to preserve as darker pixels in the final multilevel output are positioned first. We propose a solution to solve this problem in this paper. Simulation result shows that the proposed method can provide an output of better quality as compared with conventional TD-based algorithms.