Shape reconstruction and image restoration for non-flat surfaces of documents with a stereo vision system

In this paper, we propose a shape reconstruction and image restoration method for paper documents with curved surfaces or fold lines by using a stereo vision system. Characters in images of thick book´s pages acquired with an image scanner are difficult to recognize because they are deformed under the influence of curved surface. Therefore, 3-D shape reconstruction of the book´s surface is executed from the result of the stereoscopic measurement by putting the book upward, and an image of a flat surface is recovered from the curved or folded surface. The validity of the proposed method is shown through experiments.