Image processing method, image processing apparatus and data recording medium

摘要

An image processing method for dividing a digital image signal into plural image signals corresponding to plural blocks constituting a single display screen, and performing block-by-block coding of the image signals of the respective blocks, comprises transforming an image signal of a coding target block to be subjected to coding into frequency components by frame-by-frame frequency transformation on a frame basis or field-by-field frequency transformation on a field basis; setting a processing order for coding the frequency components corresponding to the image signal of the coding target block, according as the image signal of the coding target block has been subjected to the frame-by-frame frequency transformation or the field-by-field frequency transformation; and successively coding the frequency components corresponding to the image signal of the coding target block according to the order which has been set. Therefore, in coding of an interlaced image or a specific progressive image in which frame DCT blocks and field DCT blocks coexist, a run length is increased, thereby improving coding efficiency.