INTER-FRAME ENCODING DEVICE

摘要

PURPOSE:To prevent a chrominance signal from remaining on a screen when TV signals are switched from colored ones to monochromatic ones by encoding the differential value of the output of a frame memory in terms of difference and obtaining encoded outputs of a low bit rate after the inter-frame difference value of TV picture signals is suppressed by using the frame memory. CONSTITUTION:A difference encoding section 2 inputs the output of a differential value suppressing section 1 and takes a difference by using the frame memory. Then the section 2 sends encoded signals after quantizing the differential value. A timing generator 3 drives a signal selector 5 by generating pulses p1 of one time slot width by using signals expressing the color/monochrome of inputted TV signals at the moment when the TV signals are changed from colored ones to monochromatic ones and inputs the same TV signals as the changed TV signals, namely, TV signals of one frame whose burst signal B and chrominance signal C are '00' to its own frame memory by actuating a demand refreshing operation which selectively uses a signal obtained by delaying the input signal to the frame memory of the section 2 by a fixed time slot as an estimating signal by one time.