A lock device includes a first lock part, a second lock part, which can be arranged on the first lock part in a fastening direction and is connected to the first lock part in a closing state, and an actuating element, on which the second lock part is movably arranged. At least one of the first-direction and second-direction shift registers includes a transfer start control unit for selectively allowing at least two predetermined stages capable of starting transfer among the plurality of stages to start generating a transfer signal. At low power operation, only the high pressure ratio engine is operated. The video data are coded with the GCC code or the at least one sub-set code depending on the motion amplitude.