Patent Document ID: 5572603
Application ID: 08391462
Patent Status: 1

Claim One:
1. An image processing method in which each pixel data of a gray-scale image, which data is obtained by means of scanning an original, is determined as either being or not being an edge pixel corresponding to an edge of a picture of the original, the method comprising the steps of: a) preparing a 3*3 pixel matrix including a focus pixel to be processed, wherein said focus pixel is positioned in the center of the matrix and bordering pixels surround said focus pixel; and b) determining said focus pixel as either being an edge pixel or not being an edge pixel, by performing a plurality of comparisons of an intensity of said focus pixel with three intensities of respective bordering pixels of a plurality of different sets containing three bordering pixels, the three bordering pixels in each set being arranged consecutively around said focus pixel to form three intensity differences for each one of said plurality of sets, wherein: 1) the three consecutively arranged border pixels in each set include either three consecutive co-linear border pixels, or three non-co-linear pixels including a corner border pixel; and 2) said focus pixel is determined to be an edge pixel when each of the three intensity differences between said focus pixel and each of said three respective bordering pixels in any set of bordering pixels is greater than a predetermined value.