Image coding system, image decoding system, image processing system, image coding method, image decoding method, and image processing method

摘要

A raster/block conversion circuit 12 divides an input image from an image input unit 11 into blocks. An image characteristic determination circuit 13 calculates the image characteristic for each block, thereby determining the image type for each block. Based on the determination result of the image characteristic determination circuit 13, a switch circuit 18 adaptively switches an ADCT coding circuit 14 adopting a variable-length irreversible coding technique and an intrablock quad coding circuit 15, an intrablock binary coding circuit 16, and a block run length coding circuit 17 adopting a fixed-length irreversible coding technique.