APPARATUS FOR AND METHOD OF PROCESSING DOCUMENT IMAGE

摘要

An apparatus for and a method of processing a document image are provided. The apparatus comprises: an estimation unit for estimating a brightness image from the document image; and a correction unit for correcting the brightness image by using brightness values of at least a part of edge pixels which lie on or in the adjacency of edges of the brightness image in parallel with x direction, wherein directions of neighboring two edges of the brightness image are set to be x, y directions respectively, and wherein compared with x direction, brightness values of pixels of the brightness image change relatively slightly or do not change along y direction; wherein the correction unit performs interpolation on a straight line extending along y direction by using the brightness values of the edge pixels on the straight line, thereby correcting brightness values of other pixels on the straight line.

主权项

1. An apparatus for processing a document image, comprising:
an estimation unit to estimate a brightness image from the document image; and a correction unit to correct the brightness image by using brightness values of at least a part of edge pixels which lie one of on and in an adjacency of edges of the brightness image in parallel with an x direction, wherein directions of two neighboring edges of the brightness image are set to be x, y directions respectively, and wherein as compared with the x direction, brightness values of pixels of the brightness image change one of relatively slightly and do not change along the y direction; wherein the correction unit performs interpolation on a straight line extending along the y direction by using the brightness values of the edge pixels on the straight line to correct brightness values of other pixels on the straight line.