1. An image processing apparatus, comprising: a character recognizing unit configured to identify a character image in a document image; a font matching unit configured to determine a character code and a font type corresponding to the identified character image; a fore-and-background setting unit configured to set the document image as a background image and set a standard character image based on the determined character code and the determined font type as a foreground image; and a background image correcting unit configured to (a) delete a deletion area in the background image, the deletion area taking a same position as the character image or the standard character image, (b) interpolate a differential area between the character image and the standard character image in a specific neighborhood area that contacts with the deletion area on the basis of the background image, and (c) interpolate the deletion area on the basis of the back ground image.