PICTURE SIGNAL PROCESSING UNIT

摘要

PURPOSE:To improve the picture quality by magnifying again a binarized picture with respect to a picture signal reducing a multi-value picture signal by arithmetic means so as to bring the area of white and black picture element into one picture element or over thereby improving the gradation characteristic. CONSTITUTION:An input picture signal is reduced by arithmetic means at a main scanning signal 1/2 reduction circuit 2 and converted into a binary signal by a random dither binarizing circuit 3. Then the main scanning signal is magnified by repeating two picture elements at a main scanning signal double magnification circuit 4 and decoded into the original size. Thus, the minimum black/ white picture element is selected to be one picture element or over and consecutive gradation characteristic is obtained even when the signal is recorded by a conventional laser printer. Since only the main scanning picture element is subject to reproduction/magnification and recovery, the deterioration in the resolution of the picture is less. Thus, the gradation characteristic is improved and the picture quality is improved.