Image scaling method based on protected region

To solve the problem of seriously distortion while enlarging images via seam carving, we proposed an improved method in this paper. Firstly, we enlarged the image with hierarchical interpolation model to the size of power of two times of original, which is closest to target size, while applying iterative curvature-based interpolation algorithm to protected areas and nearest interpolation to non-protected areas. And then, some seams to the target size were avoided via seam carving method. Through the subjective analysis and objective evaluation, the experiment on both standard library images and spatial images showed that the proposed method gave satisfactory results.