Review of Illumination and Skew Correction Techniques for Scanned Documents

After scanning an opened page of a book, the image obtained often suffers from various scanning artifacts such as scanning shading, dark borders and skew defects. These artifacts reduce the quality of the scanned images of the documents and cause lots of problems to the process of document image analysis. Some effective methods are present to rectify these scanning artifacts. Techniques which are discussed in this paper result in the desired shading-free image and yield an illumination surface of high quality. Methods employed makes the documents skew free as well. Finally, the performances of all the methods are compared to get the most effective method for solving such problems. These techniques prove to be very appealing to non-expert users in real applications.