JPS5757081A - Conversion method for picture element density - Google Patents

Abstract

PURPOSE:To reduce the ruggedness of a picture surface to improve reproducibility of narrow lines, by converting a picture element density by the boundary direction of the density and the density. CONSTITUTION:Three-line components of input picture element information IN are transmitted to a 3X3 picture element constituting part 2 through shift registers 1 and 11. Density information of the region of 3X3 picture elements is transmitted from the picture element constituting part 2 to a boundary direction operating part 3, and density information of eight peripheral picture lelments is transmitted to a peripheral density descriminating part 4. A boundary direction D is operated by the operating part 3, and it is discriminated by the discriminating part 4 whether picture elements of density 1 and density 2 exist near eight peripheral picture elements or not. In a functional table part 5, output picture elements O1- O4 are determined on a basis of the direction D, the density of a noticed picture elements S5, presence or absence of picture elements of density 1, and presence or absence of picture elements of density 2 and are outputted in parallel. A parallel- serial converter 6 converts this output to a serial picture element information and outputs it.