Method and device for processing video data by combining error diffusion and dithering

摘要

For improving the grey scale portrayal, several dithering methods are used: Cell-based dithering, multi-mask dithering or error diffusion. Each of them has specific disadvantages. A simple combination of them does not bring expected advantages. However, an improvement is obtained if the result of the multi-mask dithering (4') is used for controlling the error diffusion (2) by a switch (8), for example.