Patent attributes
A document management system includes an image input unit that inputs a document as an electronic image; a character extraction unit that extracts character information from the input electronic image; a word extraction unit that extracts words from the character information; a document search unit that normalizes the extracted words, registers the normalized words in an index, and searches electronic images using the index; an attribute information generation unit that generates attribute information including the extracted words, positions and sizes of the extracted words, and the normalized words referring to the positions and sizes of corresponding extracted words; a search condition input unit that inputs a search keyword that is used by the document search unit when searching for a target electronic image; and a word highlighting unit that highlights the search keyword in the target electronic image found by the document search unit based on the attribute information.