2. An image processing apparatus, comprising: a first memory that stores a first document file; a linking unit that obtains entered information of the first document file and information on a position of the entered information, and stores the obtained information in association with each other in a database part; a second memory that stores a second document file obtained by revising the first document file; an extraction unit that extracts a revised area of the second document file based on the first document file corresponding to the second document file and the second document file; and a correction unit that obtains information on a position of the revised area, and corrects the entered information of the first document file, which is stored in the database part and is corresponding to the information on the position of the revised area, to entered information on the revised area.
2. An image processing apparatus, comprising: a first memory that stores a first document file; a linking unit that obtains entered information of the first document file and information on a position of the entered information, and stores the obtained information in association with each other in a database part; a second memory that stores a second document file obtained by revising the first document file; an extraction unit that extracts a revised area of the second document file based on the first document file corresponding to the second document file and the second document file; and a correction unit that obtains information on a position of the revised area, and corrects the entered information of the first document file, which is stored in the database part and is corresponding to the information on the position of the revised area, to entered information on the revised area. 5. The image processing apparatus according to claim 2 , wherein: the first document file and the second document file are obtained by scanning paper documents.