Motion compensated prediction interframe coding system

Abstract

A motion compensated prediction interframe coding system which includes a first checking portion for judging whether a motion compensation of a coding block is effective and outputting a motion compensation control signal representing the result of the judgement, a storage portion for storing motion vectors of the coding block and adjacent blocks and the motion compensation control signal, a second checking portion for comparing the motion vector of the coding block, of which the motion compensation should be effected, with each of the motion vectors of the adjacent blocks, of which the motion compensation should be effected, and judging that the intra-loop filtering processing to be performed after the motion compensation is ineffective if the number of the adjacent blocks, of which the motion vectors are identical with that of the coding block, is equal to or more than a predetermined number and that the filtering processing performed after the motion compensation is effective in another case, a motion-compensated brightness calculating portion for calculating motion-compensated brightness of pixels of the blocks, of which the motion compensation is effected, and a predictive brightness calculating portion for calculating predictive brightness of the pixels of the blocks by performing the filtering processing of the motion-compensated brightness of the pixels only if the filtering processing is effective. Thereby, the amount of the generated prediction error signals are reduced, and the picture quality is improved.