A non-linear illuminations balancing for reconstructed degraded scanned text-photo image

Due to the advancement of digital media, a large number of electronic books are digitized from old paper books through digital cameras or scanners. The scanned image often contains the distractions such as noises outside the page boundary, skewed pages, and irregular distributions of image illumination that may degrade the quality of scanned images. As for this paper, we propose an alternative algorithm to improve the illuminated distribution of the scanned images. The algorithm can be applied on the uneven illumination where significant background shadows or illumination exists. It was tested with text-photo images including different types of document and desecration. The experiment results have shown that the proposed algorithm has produced a slightly improvement in performance in some cases of the text-based images, yet the improvement can be clearly seen for text-photo images as the results were compared with LLBT and SIBT methods.