PICTURE DATA COMPRESSION METHOD AND PICTURE DATA COMPRESSION DEVICE AND PICTURE DATA DECODER

摘要

PURPOSE:To obtain a coded data not including redundant information with respect to the picture data compression method and picture data compression device and picture data decoder. CONSTITUTION:Orthogonal transformation is applied to each block comprising MXN picture elements of a picture data representing a multi-valued picture to obtain a coefficient matrix of M rows and N columns comprising conversion coefficients, plural components are extracted from a coefficient matrix corresponding to each block and an extracted coefficient matrix of M rows and N columns including only the component extracted as the effective coefficient having values other than zero is generated. The extracted coefficient matrix is subjected to inverse orthogonal transformation and a picture of each block is decoded and plural picture elements are extracted respectively from the obtained picture, a reduced picture comprising the picture elements is generated corresponding to each block and sets of the reduced pictures corresponding to each block are used as picture data and they are coded and compressed furthermore.