Projection profile based skew estimation algorithm for JBIG compressed images

Junichi Kanai, Andrew D. Bagdanov

Abstract: A new projection profile based skew estimation algorithm is presented. It extracts fiducial points corresponding to objects on a page by decoding a JBIG compressed image. These points are projected along parallel lines into an accumulator array. The angle of projection within a search interval that maximizes alignment of the fiducial points is the skew angle. This algorithm and three other algorithms were tested. Results showed that the new algorithm performed comparably to the other algorithms. The JBIG progressive coding scheme reduces the effects of noise and graphics, and the accuracy of the new algorithm on 75 dpi unfiltered images and 300 dpi filtered images was similar.