Apparatus for processing image signal

摘要

An image signal processing circuit for converting a continuous tone image signal to a bi-level image signal, for producing a spatial gray scale image on a bi-level display device such as a gas plasma display panel. Respective values of apportionment factors (KA to KD) used for apportioning a bi-level conversion error of each picture element of the image among a plurality of picuture elements (A to D) positioned peripehrally adjacent thereto are periodically altered, in a periodic or random succession of values, to thereby effectively eliminate the generation of a texture pattern in display regions corresponding to areas of uniform density in the original image.