PICTURE COMMUNICATION SYSTEM

摘要

PURPOSE:To allow a receiver side to control picture quality and code quantity by sending a control signal from the receiver side to a sender side and allowing the sender side to apply invalid block processing based on a relevant criterion. CONSTITUTION:A prediction section 4 of a sender side A generates a predicted picture, a subtraction section 5 calculates a difference signal between an input picture i1 and a predicted picture i2 and a processing section 6 applies ineffective block processing to a difference signal. In this case, in the adjustment of a threshold level, by considering the relation between picture quality and code quantity a control signal from an input section 15 at a receiver side B is sent to a threshold level adjustment section 19 via a transmission section 16, a transmission line 17 and a reception section 18 to adjust the threshold level at the processing section 6. As to a difference signal after the ineffective block processing, a coding section 7 applies block coding and the result is sent via the transmission line 11.