1. In a page analysis system for analyzing image data of a document page, a method for increasing the accuracy of image data classification, the method comprising the steps of: inputting image data of a document page as pixel data; a first analyzing step for analyzing the pixel data in order to locate all connected pixels; rectangularizing connected pixel data into blocks; a second analyzing step for analyzing each block of pixel data in order to determine type of image data contained in each block; outputting an attribute corresponding to the type of image data within the block determined in the second analyzing step; and performing optical character recognition so as to recognize image data in a block in the case that the second analyzing step cannot determine a type of image data contained in the block.