ADAPTIVE DECODER FOR CONTINUOUS IMAGE

摘要

PROBLEM TO BE SOLVED: To provide a decoding device capable of reproducing also fine portions of an image in a high quality state by utilizing the redundancy of information existing in continuous images when an image indicates a scene of little movement or a completely static scene. SOLUTION: A decoding device is provided with; 1st means 52 to 55 for receiving encoded data consisting of an encoded value and a codeword generated by comparing with a threshold each conversion coefficient corresponding to a low spatial frequency and a corresponding conversion coefficient of a block corresponding to a preceding image in order to display that the block is a highly animated scene or a slightly animated scene, and to generate a control signal and for restoring the decoded value of a coefficient or a coefficient difference based on the encoded value; a 2nd means 62 for adding the decoded value outputted from the 1st means 52 to 55 to the value of the corresponding coefficient of the corresponding block of the preceding image and for determining one value in each coefficient of the block; and a multiplexer 56 controlled by the control signal generated from the 1st means 52 to 55 and capable of outputting either one of the decoding value restored by the 1st means 52 to 55 or the value determined by the 2nd means 62.