Gray scale processing for a display device, using error diffusion

摘要

In an error diffusion processing unit one dot of input signal is converted into plural picture elements. The respective picture elements (pixels) thus converted are compared with prior data to detect the luminance error, which will then be weighted by multiplying it with certain coefficients to give, for instance, the reproduced vertical error, horizontal error and diagonal error which will respectively be added to the original pixels. Producing a false tone by error diffusion in units of pixel enables to display the half tone without reducing the spatial resolution.