EDGE DETECTION METHOD DETECTING PIXEL WITH ALIAS ELIMINATED THEREFROM AND DEVICE FOR DETECTING PIXEL ON BORDER LINE INCLUDING THE PIXEL

摘要

PROBLEM TO BE SOLVED: To provide the method that detects an image area with alias eliminated therefrom and generates a rendering tag in a text from which alias is eliminated or in an architecture designed for rendering a line area. SOLUTION: A histogramer 204 decides a threshold level for one area of an image in the logical base execution of the edge detection method. In a 1st channel (C1) of the image, a threshold level used to apply binary processing to an image area and decided as a function of a 1st image reference is set, a vector with an existing set of pixels in the binary-processed image area is extracted and applied to a logical arithmetic operation, and suggesting the presence of an existing pattern as output when the existing pattern is present. In a 2nd channel (C2), the similar steps to the channel 1 are conducted. A tag map 216 combines logically the 1st and 2nd channels and generates a tag suggesting the presence or absence of pixels on a gray border line in the image area.