自补偿灰度误差的带子元有序抖动

An ordered dither method with the subcell for the self compensating gray error

有序抖动是一种典型的数字半调方法，在用于打印时，印点的部分重叠现象将严重破坏灰度级的线性性，使输出图像的灰度和色彩出现明显失真．针对此现象，提出了一种自补偿灰度误差的有序抖动方法（带子元有序抖动）．该方法可真实再现原始图像的灰度和色彩，突破了常规有序抖动不能同时减少人工纹理和灰度误差的局限．

As a conventional digital halftone method, the ordered dither is widely used for its distingwished features: high detailed rendition, easy parallelization and also simple and fast implementation. However, when an image is printed instead of being displayed on the CRT, the linearity of the gray scale is obviously distorted, which is mainly caused by dot overlap. In view of this problem, a new ordered dither technique, which can compensate the dot gain without changing the gray resolution, is proposed in this paper. It resolves the problem sucessfully and, unlike the traditional method, it also reduces the artifice and distortion to the gray scale.