Picture decoding method and apparatus, and picture encoding method and apparatus

Abstract

The present disclosure discloses picture decoding methods and apparatuses, and picture encoding methods and apparatuses, relating to the field of video coding and decoding technologies, and solving the problem of low prediction efficiency in a process of picture coding and decoding (or video coding and decoding). The picture decoding method includes: parsing a bit stream to obtain a syntax element, where the syntax element is configured to obtain a residual block of a to-be-decoded unit, and the to-be-decoded unit includes at least one prediction group; determining a prediction mode of any one prediction group in the at least one prediction group; obtaining a prediction value of the any one prediction group by performing prediction for the any one prediction group with the prediction mode; and decoding the to-be-decoded unit based on the residual block of the to-be-decoded unit and the prediction value of each one in the at least one prediction group.