MOVING PICTURE ENCODER

摘要

PURPOSE:To reduce picture quality deterioration in the central part of a picture by executing an encoding processing from the center of the picture and changing an apparent transmission memory capacity and quantization characteristics for every plural areas according to the sequence of an encoding processing. CONSTITUTION:An input picture, after being accumulated in a picture memory part 1, is read out in a sequence from the center of the picture to a periphery in a block unit. An adaptive type quantization part 13 quantizes the respective factors of transformation factor matrix being the output of an orthogonal transform part 6 in order to delete the kind of information to be encoded, but the quantization characteristics is made its step into smaller in the central area of the picture and larger in the peripheral area. An adaptive type transmission memory 14 has an apparently large memory capacity when the central part of the picture is encoded and has a small capacity when the circumferential part is encoded. The picture quality deterioration can be reduced by executing an encoding processing from the center of the picture which is visually important.