We have developed a mobile robot camera that can move in any lateral direction, as well as up and down, as a tool for efficient program production. The system adopts methods that utilize a gyrosensor and the number of wheel revolutions to determine the camera's position, and that enable a high degree of positioning accuracy. It also uses a unique filming algorithm that simulates the operation methods used by human camera operators. Therefore, the robot camera can shoot scenes with natural camerawork. Moreover, we have developed a highly accurate image composition system using this mobile robot camera as a tool for the efficient production of HD virtual studio programs. The system is currently being operated on a continuous basis as a practical camera in live broadcasts as well.