PICTURE CODER AND DECODER

摘要

PURPOSE:To obtain a picture coder showing excellent performance under a high compression rate by picking up a texture of a picture so as to add information related to the texture to a code. CONSTITUTION:Data are segmented into blocks of a predetermined size by a block segmentation means 102 and the block is fed to a DCT transformation section 103, in which the block is transformed into a frequency region. An inverse DCT transformation section 104 generates a reproduced picture from a DCT coefficient for a low frequency within a prescribed range after the quantization. A texture characteristic extract section 105 extracts two fractal characteristic quantities based on the difference between the reproduced picture obtained by the transformation section 104 and the original picture. An output of the transformation section 103 and an output of the extract section 105 are converted into a code by a quantization coding section 106 and the operation of the coding section 106 is controlled by the operation of a fractal characteristic discrimination section. That is, to which of a DCT coefficient obtained from the transformation section 104 or the characteristic quantity obtained from the extract section 105 is used for emphasis for the coding is discriminated.