Image resizing via bi-quadratic B-spline interpolation
双二次B-样条插值图像缩放

Bilinear interpolation and various bi-cubic interpolations are frequently adopted in image resizing. However the bi-quadratic function is rarely considered due to its phase distortion problem. In this paper, we propose an image resizing method via bi-quadratic B-spline interpolation, where 4×4 pixels are sampled symmetrically in the local image. and resamping the image with the function,Thus the phase distortion problem can be avoided. The proposed algorithm is a local algorithm and can be easily extended.According to our experiment results,the proposed bi-quadratic B-spline interpolation algorithm has better image peak signal-to-noise ratio (PSNR) and MISSIM than bi-linear interpolation, bi-cubic convolution, Catmull-Rom cubic interpolation, or the Dodgson interpolation algorithm.The results are comparable to the bi-cubic B-spline interpolation algorithm,though the visual effects are not as good as that,but still better than the Dodgson algorithm. The computing time is reduced by nearly one-third compared to the bi-cubic B-spline interpolation algorithm.Since the algorithm has not carried on the special handling to the image edge features,so the method does not suit the rich details texture images,which we will focus on in the future days.