1. An application processor, comprising: an image signal processing circuit to receive a image signal from an image sensor; and a memory controller to control a data processing operation of a memory device, wherein the image signal processing circuit comprises: a distortion correction circuit to correct a distorted image into an undistorted image; and an image enhancement circuit to improve the undistorted image using a high-frequency component of the distorted image, wherein the distortion correction circuit corrects the distorted image using a size of a Gaussian interpolation kernel controlled according to a degree of distortion determined based on a distance from a center of a image, and wherein a plurality of patches in the distorted image and a plurality of patches in the undistorted image each include a low-frequency component and a high-frequency component.