METHOD FOR IMPROVING COLOR PRINTER RESOLUTION USING NONLINEAR QUANTIZATION AND MODIFIED DOT DIFFUSION OF HVS (HUMAN VISUAL SYSTEM)

摘要

The present invention relates to improving the resolution of a color printer using modified print point spreading using nonlinear quantization and human visual characteristics in consideration of overlapping of printed points in color printing.;Most modern printers linearly quantize a pixel with a large number of bits to a pixel value with a smaller number of bits, and when printing a point on the paper, it is printed in the form of a circle with respect to the center of the area to be painted, not a square. . Therefore, a phenomenon in which the intensity of the printed image is different from the intensity of the image displayed on the computer monitor, which causes a problem that the color area of the printed dot is changed according to the coloring position and order of the printed dot.;In addition, since the quantization error does not consider the effect on the human vision according to the color and the effect of the quantization error on the background, an output image having a resolution different from that displayed on the monitor is displayed.;In order to solve this problem, the present invention applies non-linear quantization that sets the quantization interval differently in consideration of the area changing according to the position and order in which the printed points are colored, and the human vision is applied to the high frequency background rather than the error of the low frequency background. Color by adjusting the color sensitivity of quantum and error according to HS (hue saturation intensity) color coordinate system using quantization error and quantization value obtained by lowpass filtering quantization error by using characteristic that error is less sensitive to human vision The resolution of the printer can be improved to output images with better image quality.