1. An X-ray imaging apparatus comprising: an X-ray source configured to emit X-rays to an object at different original-view positions; an X-ray detector configured to detect the X-rays having passed through the object to acquire original-view images corresponding to respective original-view positions; and an image controller configured to reconstruct a three-dimensional (3D) volume of the object from the original-view images and generate close-view images by virtually emitting X-rays to the 3D volume of the object from a shorter distance than a distance between the X-ray source and the object.