Display device and control method thereof

A method of controlling a display device, the display device comprising a mirror display, a motion sensor configured to sense a motion of a user, a two-dimensional camera, and a three-dimensional camera, the method comprising:

• photographing a three-dimensional face image of a user at a first time point by using the three-dimensional camera;
• photographing a three-dimensional face image of the user at a second time point by using the three-dimensional camera;
• detecting a facial contour of the user from the three-dimensional face image of the user photographed at the first time point;
• detecting a facial contour of the user from the three-dimensional face image of the user photographed at the second time point;
• identifying a change of the facial contours between the first time point and the second time point based on the detected facial contours;
• displaying information about the change of the facial contours on the mirror displays;
• activating the three-dimensional camera when the motion sensor detects the motion of the user;
• detecting a predefined gesture from a three-dimensional image photographed by the three-dimensional camera;
• and
• activating the mirror display when the predefined gesture is detected.