Image information encoding method and encoder, and image information decoding method and decoder

摘要

A motion compensation method includes receiving mode information that identify a field motion estimate/compensate mode. The method further includes performing, on the basis of the mode information, a motion compensation of a decoded image signal including a luma signal and a chroma signal in a format in which the number of chroma pixels is vertically different from the number of luma pixels. The method further includes detecting a condition that a reference field has a different parity from a current field for a motion compensation. The method also includes controlling, in the detected condition, the motion compensation so as to vertically shift a phase of the chroma signal in the reference field so that the reference field will coincide in phase of the chroma signal with a current field.