shown in fig5 immediately after the data such as a a 39 b and b 39 enters the data such as c and c 39 of the next block enters the quantized signals are delayed by a predetermined time in third delay 47 during performing the mode selection mode selection signal s m of mode selector 46 is supplied to switch sw as a result one among the data of four modes of third delay 47 is selected thereby performing the dc dpcm again here the dc dpcm portion 48 performs the dc dpcm in order of a b c 39 and d 39 in a dotted direction in fig5 also third dc dpcm portion 48 performs the dc dpcm only when the input data is an intramode the intermode video data is transmitted to a next block as it is the data outputted from dc dpcm portion 48 is supplied to a transmission channel via variable length coder 49 and buffer 50 on the other hand a decoding portion comprises an inverse quantizer 51 a dc detector 52 an inverse dct portion 53 and a video restoring unit 54 to thereby obtain the motion compensated block data in the course of the dpcm processing this restored block data is stored in a frame memory 55 motion predictor 56 predicts a motion from a portion corresponding to the block data currently input to first frame arranger 31 among the data of the previous frame stored in frame memory 55 and detects a motion vector motion compensator 57 uses the.