1. A method in a computer system for determining relatedness between images within blocks of pages, the method comprising: calculating indicators of importance of a block to a page; calculating indicators of importance of a page to a block; calculating indicators of importance of an image to a block; and calculating image-to-image indicators of relatedness of an image to another image by combining the indicators of importance of a block to a page, the indicators of importance of a page to a block, and the indicators of importance of an image to a block.