Method and device for intra prediction

A video decoding method, comprising:

• receiving, by a decoding apparatus, index information indicating a candidate mode of an intra prediction mode of a current block;
• constructing, by the decoding apparatus, a candidate mode list including a plurality of candidate modes for the current block;
• determining, by the decoding apparatus, the intra prediction mode of the current block based on the candidate mode indicated by the index information from the plurality of candidate modes constituting the candidate mode list;
• and
• generating, by the decoding apparatus, a predicted sample in the current block based on the determined intra prediction mode,
• wherein the constructing the candidate mode list includes:
• setting a first ordered candidate mode and a second ordered candidate mode, among the candidate modes of the candidate mode list, based on a first block adjacent to the left side of the current block and a second block adjacent to the upper side of the current block,
• wherein the first ordered candidate mode is set equal to a planar mode and the second ordered candidate mode is set equal to a DC mode when the both of the first block and the second block are not available.