1. An image processing apparatus comprising: a processor to control one or more processor-executable units; a silhouette extractor to extract a silhouette image of a target object from an input depth image; and a first calculator, controlled by the processor, to determine a location of at least one limb of the target object and a location of at least one joint of the target object by applying a rectangle fitting algorithm with respect to the silhouette image, wherein the first calculator performs face detection with respect to the silhouette image, detects a torso portion using the rectangle fitting algorithm based on a detected face portion, and applies the rectangle fitting algorithm by using a corner of a torso portion rectangle of the detected torso portion to determine the location of the at least one limb and the location of the at least one joint, and wherein the first calculator calculates a first feature point based on the applying of the rectangle fitting algorithm with respect to the silhouette image; and a second calculator, controlled by the processor, to calculate a second feature point based on the first feature point calculated by the first calculator using an inverse-kinematics scheme, to generate a skeleton model using the first feature point calculated by the first calculator and the second feature point calculated by the second calculator, wherein the second feature point calculated by the second calculator comprises an additional point location on the skeleton model different than the first feature point calculated by the first calculator, and to calculate motion capture information of the target object using the generated skeleton model.