1. A depth image processing apparatus, comprising: a depth image obtainer configured to obtain depth images; a camera pose converter configured to convert camera poses of the depth images into a camera pose of a reference depth image; and a depth image filter configured to filter the reference depth image based on the depth images with converted camera poses, wherein the camera pose converter is further configured to convert the camera poses of the depth images by obtaining relative camera pose values of the depth images based on the reference depth image.