PURPOSE: To reduce a coding noise, and to improve the quality of a picture by providing a means to detect the moving amount of a video signal, the means to output cut-off frequency, a lowpass filter, and the means to execute the encoding processing of the band-limited video signal.

CONSTITUTION: A motion detector 101 detects and outputs the moving amount 106 of each picture of the video signal 105. A cut-off frequency outputting device 102 outputs the low cut-off frequency 107 if the moving amount 106 is large, and outputs the high cutoff frequency 107 if the moving amount 106 becomes small. Besides, the low-pass filter 103 bnad-limits the video signal 105 by the cut-off frequency 107. Then, an encoder 104 executes the encoding processing of the video signal 108 having been band-limited by the low-pass filter 103, and obtains a code string 109. Thus, the video signal of the large moving amount is band-limited by the low-pass filter of the low cut-off frequency.