MOTION COMPENSATION HIGH EFFICIENCY CODING SYSTEM, MOTION COMPENSATION HIGH EFFICIENCY CODER, MOTION COMPENSATION HIGH EFFICIENCY DECODING SYSTEM AND MOTION COMPENSATION HIGH EFFICIENCY DECODER

摘要

PURPOSE:To improve the compression rate of transmission data. CONSTITUTION:DCT quantization circuits 7, 9 quantizes input image data. Inverse quantization inverse DCT circuits 15, 17 decode quantized data and the decoded data are added to data of a preceding frame subject to motion compensation. A frame memory 21 delays an output of an adder 19, a replacement circuit 31 of a next stage replaces data at the outside of a valid image with a prescribed value K and the replaced data are added to the delayed data. Input data are delayed by a frame memory 27 and a replacement circuit 33 of a next stage replaces the delayed data with a prescribed value similarly. A motion vector detection circuit 29 detects a motion vector from the input data and output data of the replacement circuit 33 thereby allowing a motion compensation circuit 23 to apply motion compensation to the output of the replacement circuit 31. The compensated data and the input data are given to a subtractor 3, in which a difference is taken and the difference is given to the quantization circuit as above.