The present application discloses an image interpolation method for interpolating a pixel and enhancing an edge in an image, comprising detecting an edge position in an image; obtaining edge characteristics associated with the edge position; determining whether an interpolation point is located within an edge region based on the edge characteristics of an array of p×q pixels surrounding the interpolation point, wherein p and q are integers larger than 1; determining edge direction of an interpolation point located within the edge region, wherein the edge direction is normal to gradient direction; classifying the edge direction accordingly to in angle subclasses and n angle classes; wherein each angle class comprises one or more subclasses, m and n are integers, and n≤m; selecting a one-dimensional horizontal interpolation kernel based on the angle class; performing a horizontal interpolation using the selected one-dimensional horizontal interpolation kernel; and performing a vertical interpolation using a one-dimensional vertical interpolation kernel.