(a) receiving a multiview color-depth video and a high-resolution video;

(b) extracting a body skeleton from the multiview color-depth video;

(c) detecting face and hand regions by using joints of a neck and a wrist of the body skeleton;

(d) extracting a joint of a predetermined detail level from a region of the high-resolution video corresponding to the face and hand regions; and

(e) generating motion data by integrating a body joint and the joint of the predetermined detail level,

wherein the step (b) includes:

(b1) generating a point cloud of a three-dimensional object;

(b2) acquiring a projection image obtained by projecting the point cloud of the three-dimensional object onto at least three projection planes that are different from each other;

(b3) acquiring a two-dimensional skeleton image in each direction for each of at least three projection images by using a neural network, in which a two-dimensional joint and a bone configured to connect joints to each other are displayed in the two-dimensional skeleton image;

(b4) restoring the two-dimensional skeleton image in each direction, and detecting a three-dimensional internal joint by using a restored three-dimensional surface joint in each direction; and

(b5) generating a three-dimensional body skeleton including the detected three-dimensional internal joint.