Abstract: Use is made of a digitally assisted DATV to effect a bandwidth reduction encoding and bandwidth reduction decoding, in addition to MAC-coding and MAC-decoding, of at least three picture signal channels (PC) each having a different picture signal refresh period equal to, for example, 80, 40 and 20 ms which are coupled via a time-division multiplex circuit (MUX). For with the diversity of picture signal sources, it was found that distinguishing during the picture signal processing between a film mode (SW1, T40) and a non-film mode (SW1, T20) results in a significantly improved high-definition picture resolution. This distinction is expressed at the DATV by one information bit (FM'). During the non-film mode (SW1, T20) three Y-liminance channels (PC11, PC13 and PC12) of 80, 40 and 20 ms and two U and V-chrominance channels (PC21 and PC22) of 80 and 20 ms are operative. During the film mode (SW11, T40) the Y-channels (PC11 and PC13) and the U and V-channels (PC21 and PC23) of 80 and 40 ms are only operative.

Abstract: A television picture memory (MEM) containing digital picture signal values associated with picture elements (PIX) is coupled via a picture signal value comparison circuit (COM1) and an absolute value circuit (ABS1) to an adaptive threshold circuit (THR) for the picture signal differences. In order to obtain a motion detection with a directional sensitivity in the horizontal and vertical direction, the threshold circuit (THR) has an adaptive horizontal and vertical threshold value - adapting circuit (ADA) which produces the adaptive threshold values (HI and VI) via maximum value passing circuits (H MAX and V MAX) which are coupled to the memory (MEM) via an absolute value circuit (ABS2), a picture signal comparison circuit (COM2) and a signal combining circuit (AVE2), and by-passing it.