A Method of Restoring the Shadow Distortion in a Bounded Book Scanned Image by Using Non-Edge Segment

摘要

When a thick bounded book is scanned on a flatbed scanner, the folding areas adjacent to the left page and right page would not be contacted on the glass. Therefore, the folding areas are darkened because the light reflected from the folding areas is weakened. In order to restore the shadow distortion in the folding areas, distortion profile should be firstly estimated. This paper proposes a method for estimating shadow distortion from the bounded book scanned image itself and for restoring the shadow distortion. The estimation of the shadow distortion can be done by analyzing the information of the non-edge segment which consists of non-edge pixels. The analysis of the change of the average luminance in the non-edge segments can estimate the characteristics of the shadow distortion.