Prediction method and device using reference block

Abstract

Disclosed herein are a video decoding method and apparatus and a video encoding method and apparatus. In the encoding and decoding of a video, a prediction mode may be selected from among multiple prediction modes using prediction mode information for a target block, and prediction may be performed on the target block based on the selected prediction mode, wherein the prediction mode information includes information related to a reference block, and wherein the reference block comprises one or more of a spatially neighboring block that is spatially adjacent to the target block and a temporally neighboring block that is temporally adjacent to the target block. When the selected prediction mode includes a plurality of prediction modes, a prediction mode to be used for prediction of the target block may be decided on among the plurality of selected prediction modes through signaling of the prediction mode decision information.