Provided is a video decoding method including: obtaining affine parameter group candidates of a current block based on whether adjacent blocks of the current block are decoded; determining an affine parameter group of the current block from among the affine parameter group candidates, according to affine parameter information of the current block; and reconstructing the current block, based on one or more affine parameters included in the affine parameter group.
FIG. 12 illustrates that a processing order between a plurality of coding units may be changed depending on a process of splitting a coding unit, according to an embodiment.