IEEE Trans Image Process. 2015 Nov;24(11):4581-91. doi: 10.1109/TIP.2015.2470599. Epub 2015 Aug 24.
Compared with the error diffusion, dot diffusion provides an additional pixel-level parallelism for digital halftoning. However, even though its periodic and blocking artifacts had been eased by the previous works, it was still far from satisfactory in terms of the blue noise spectrum perspective. In this paper, we strengthen the relation among the pixel locations of the same processing order by an iterative halftoning method, and the results demonstrate a significant improvement. Moreover, a new approach of deriving the averaged power spectrum density is proposed to avoid the regular sampling of the well-known Bartlett's procedure which inaccurately presents the halftone periodicity of certain halftoning techniques with parallelism. As a result, the proposed dot diffusion is substantially superior to the state-of-the-art parallel halftoning methods in terms of visual quality and artifact-free property, and competitive runtime to the theoretical fastest ordered dithering is offered simultaneously.
与误差扩散相比，点扩散为数字半色调提供了额外的像素级并行性。然而，尽管之前的工作已经减轻了其周期性和块状伪影，但从蓝噪声谱的角度来看，它仍然远不能令人满意。在本文中，我们通过迭代半色调方法增强了同一处理顺序的像素位置之间的关系，结果表明了显著的改进。此外，还提出了一种新的平均功率谱密度推导方法，以避免众所周知的 Bartlett 过程的规则采样，该过程不准确地表示具有并行性的某些半色调技术的半色调周期性。因此，与最先进的并行半色调方法相比，所提出的点扩散在视觉质量和无伪影方面具有显著优势，同时与理论上最快的有序抖动相比具有竞争力的运行时间。
