A space-variant cubic-spline interpolation

In this paper, a space-variant cubic-spline interpolation (CSI) scheme by the use of the warped distance is developed to improve the performance. Furthermore, a modified overlap-save sub-image method is introduced to solve the boundary condition problems that occur between two neighboring subimages in the actual image. Experimental results show that the proposed improved CSI scheme can actually achieve a better PSNR than the existing interpolation algorithms including the original CSI scheme.