PURPOSE: To quickly detect a moving quantity of a camera by sending a control signal representing a direction of camera movement and its amplitude to a picture coding section and suppressing a picture data output when the signal is received.

CONSTITUTION: When the direction of a camera 10 is changed, a camera control section 1 sends a control signal representing a direction of camera movement and its amplitude, the direction is changed by the amplitude and the control signal is inputted to a control section 3-1 of a picture coding section 2. Then a picture signal from the camera 10 is sampled by a sampling section of a coding section 2 implementing coding in matching with a characteristic of picture data. Furthermore, the sampled picture data are quantized by a quantization section 8, and a coding section 9 finds out the characteristic of picture data and encodes the data by an optimum method and outputs the result. In this case, the control section 3-1 suppresses the picture data output while the section 3-1 receives the control signal from the control section 1 and reduce the size of the picture data sampled by the sampling section 7 by increasing the quantization step of the quantization section 8. Then the moving quantity is quickly detected even when the direction of the camera 10 is changed.