Document mosaicing

摘要

Document scanning with an over-the-desk video camera offers an attractive alternative to the flat-bed scanner, photocopier or fax machine, since the documents need not be moved from their usual place of reading. However, standard CCD cameras can sample full A4 pages at only 50 dots per inch, which is not sufficient for anything more than the crudest reproduction. This motivates the use of “mosaicing”, whereby multiple, overlapping images of the document are stitched together seamlessly to form a high resolution composite. Here we present a novel mosaicing system optimized for use with documents. The user simply slides the paper under the camera: all subsequent processing is fully automatic. The quality of the resulting images is sufficient for OCR or printing, though some post-processing is necessary.