Patent ID: 8634472

Claim:
An image decoding method comprising: receiving mode information that identifies, on a block basis, a field motion estimate/compensate mode; performing, on the basis of the mode information, a decoding process on an encoded image signal to generate a decoded image signal including a luma signal and a chroma signal in a color information format in which the number of chroma pixels is vertically different from the number of luma pixels; detecting a different parity condition that a reference field is a top field while a current field is a bottom field for a motion compensation; performing, on the block basis, the motion compensation of the decoded image signal using a luma motion vector and a chroma motion vector; and controlling, in the detected different parity condition, the motion compensation so as to phase-shift the chroma pixel of the chroma signal on the block basis according to an accuracy of the luma motion vector of the luma signal and an accuracy of the chroma motion vector of the chroma signal so that a reference block will coincide in phase of the chroma signal with a current block.