METHOD AND DEVICE FOR ADJUSTING GRAYSCALE

摘要

PURPOSE: A method and a device for adjusting a grayscale are provided to a vary an angle of a half tone screen and a line length per inch, thereby outputting an image with high definition. CONSTITUTION: Luminescence levels of a notable pixel and adjacent pixels near the notable pixel are binarized using a half tone screen(10). Whether the notable pixel is a text area or an image area is determined using location information between the notable pixel and the adjacent pixels arranged in each center of sub cells included in a window configured based on the notable pixel(12). If the notable pixel is an image area, an average of the binarized levels of the notable pixel and the adjacent pixels is calculated(14). If the notable pixel is a text area, the binarized level of the notable pixel is determined as a gray value of the notable pixel, or after the step 14, a certain value corresponding to the average is determined as a gray value of the notable pixel(16). The location information is variable and includes distances between the notable pixel and the adjacent pixels, and angles of line segments connecting the notable pixel and the adjacent pixels.