Abstract: A method and image processing system is for reconstruction of an input image. The method for reconstruction of an input image includes a step of inputting image data (for example, densities) of at least two pixels nearest to a position of an additional pixel to be added to the input image and those of neighbor pixels located on extension lines of segments drawn between the position of the additional pixel and that of each of the nearest pixels of which the image data were inputted, and a step of estimating the value of the image data of the additional pixel on the basis of the inputted image data of at least two pair of the nearest and corresponding neighbor pixels by using an improved and simple algorithm which is newly proposed herein and called "linear extrapolation and average method".

Abstract: Apparatus and method for generating screened halftone images, which includes means for assuming an area of halftone dots with desired periodicity and tone reproducibility, subdividing the area into minute cells and setting address values (X, Y) for each of the minute cells, computing out a threshold value of density for each of said cells as a function f (X, Y) of the relevant address values (X, Y), and using the computed value as threshold value of density for the cell, means for obtaining a density-related video signal of the portion of the original corresponding to each of said cells by scanning the original, and means for producing halftone dot signals by comparing the video signals and the threshold value of density with each other.

Abstract: A protective coating material for lithographic printing plate, which comprises pullulan or pullulan derivatives. Said material is superior to hitherto used gum arabic solution in the protection of the surface of lithographic printing plate against oxidation and scumming as well as in the ability to enhance the hydrophilic character of metallic surface of a non-image area.