Abstract: An image data generating circuit of a color image processing apparatus generates multivalued image data for each color in accordance with density of each color of magenta (M), cyan (C) and yellow (Y). An M-screen threshold value generating circuit outputs a plurality of first threshold values, a C-screen threshold value generating circuit outputs a plurality of second threshold values, and a Y-screen threshold value generating circuit for outputting a plurality of third threshold values. A comparing circuit compares the multivalued image data outputted from the image data generating circuit with the first to third threshold values outputted from the M-, C- and Y- screen generating circuits for each color to output a comparison result in the form of a binary signal. The first and second threshold values is assigned to each pixel of an M multi-cell and a C multi-cell constituted by square matrixes having screen angles of .+-.tan.sup.-1 (q/p) and each side of .beta..multidot.p.multidot.q, respectively.

Abstract: Color video signals representing gradation values of yellow, magenta, cyan and black components of a halftone original are stored into respective video memories (4) and matrix patterns of screen values are stored in respective areas of a screen memory (7) corresponding to the colors of the video signals. Each matrix pattern has repeating areas extending in a direction inclined to the orientation of the original at an angle .phi. which satisfies tan .phi.=1/(tan .theta.+cot .theta.). Each of the color signals is retrieved from the video memories (4) at line intervals depending on the screen angle .theta. so that if the video signal is reconstructed on a hypothetical plane the line starting points of a resultant image would substantially delineate a line path that is inclined to the orientation of the original by an amount corresponding to the screen angle .theta. of the color of the video signal.