The disclosure discloses a method and device for coding an image and a method and device for decoding an image. The coding includes that: a coding block is partitioned into L micro-blocks, wherein L is a preset number of micro-block partitions in the decoding block; Displacement Vectors (DVs) between the micro-blocks and reference micro-blocks in a preset reconstructed pixel sample set are determined, wherein the DVs are vectors between pixel positions of the reference micro-blocks and pixel positions of the micro-blocks in a preset pixel coordinate system; and the DVs are coded and written into a bitstream. By the methods and the devices, the problem of low image compression and decompression efficiency during image coding and decoding in the related technology is solved, and the effect of improving image coding and decoding efficiency is further achieved.