US Patent 7257567 Document retrieving method and apparatus

In the proposed document retrieving apparatus, text feature data that bases upon text data included in a document and image feature data that bases upon a document image are stored in a memory. Image data of a search document is subjected to character recognition processing, text feature data is acquired based on the obtained text data, and image feature data (layout data) is acquired based on the image data of the search document. Using the text feature data and image feature data acquired with respect to the search document, a memory is searched, and a document corresponding to the search document is retrieved from plural documents.