Dither estimation based on pixel histograms

Summary form only given. In this paper, a pixel-histogram (PH) based dither estimation (DE) method is proposed. The PHDE method utilizes pixel histograms of the halftone rather than the block histograms used by the previous full-dot pattern (FDP) approach. It is then less affected by the growing of the dither size than the FDP approach. The PHDE approach also explores the component structure of clustered-dot dither to suggest an averaging operation over the neighboring histograms, which can reduce considerably the number of missing dither components. The experimental results show our PHDE method was very effective and much better than the FDP approach.