| 摘要 |
PROBLEM TO BE SOLVED: To extract even a lightness-inverted region having a complicated shape as a lightness-inverted region more appropriately, and generate a binary image more suitable for character recognition. SOLUTION: There are provided: an image acquisition section 11 for acquiring multi-value image data; an image dividing section 13 for dividing a multi-value image corresponding to the multi-value image data into blocks; an edge detection section 15 for detecting the presence of an edge for each of the blocks; a binarization threshold calculation section 16 for calculating a binarization threshold for blocks in which an edge is detected; a block determination section 17 for determining whether a target block is a normal block or an inverted block based on the information of the presence of an edge or the information of the presence of an edge and a binarization threshold; and a region creation section 18 for creating a region by connecting blocks based on the result of the determination. COPYRIGHT: (C)2009,JPO&INPIT |
