纹理细节和边缘结构保持的图像插值算法

In order to solve the problem that in the process of image reconstruction destroys the edge structure and losses the texture detail , this paper proposed an image interpolation algorithm for preserving the texture detail and the edge structure. Firstly, image divides area by using eight direction edge detection based on adaptive threshold. Secondly, construct a bivariate rational function model, which can convert into rational model and polynomial model. Finally, based on the local asymmetry edge data and gradient feature, this paper proposed a method to adjust the distance of points to be interpolated. By this method, adjusting the coordinates of the points to be interpolated and using rational model to realize interpolation, as for the non edge part, adopt polynomial model to interpolation. Experiments show that, the peak signal to noise ratio of the algorithm increases 0.48db-2.17db on average, and the structural similarity index increases 0.004-0.028 on average. This algorithm obtains high objective evaluation data. In this algorithm, the original spatial distance invariant interpolation is modified to the spatial distance varying interpolation, which effectively keeps the edge structure and texture details of the image, and makes the reconstruction result have better visual effect.