Encoding method and device therefor, and decoding method and device therefor

A video encoding method comprising:

• generating encoding order information indicating an encoding order indicating whether a second coding unit is decoded prior to a first coding unit in a current coding unit, the first coding unit and the second coding unit being split from the current coding unit;
• determining encoding information indicating an intra prediction mode for the first coding unit among a plurality of intra prediction modes, the plurality of intra prediction modes including directional modes and non-directional modes;
• and,
• when the second coding unit is decoded encoded prior to the first coding unit and a first mode among the plurality of intra prediction modes is used for prediction on the first coding unit, obtaining a predicted sample in the first coding unit using a left sample, a bottom-left sample, a right sample, a bottom-right sample and a upper sample,
• wherein the right sample and the bottom-right sample are located in the second coding unit adjacent to the first coding unit,
• the left sample, the bottom-left sample and the upper sample are located in coding units adjacent to the first coding unit, the coding units being encoded prior to the first coding unit.

A video decoding device comprising:

• an extractor configured to obtain, from a bitstream encoding order information indicating an encoding order indicating whether a second coding unit is decoded prior to a first coding unit in a current coding unit, the first coding unit and the second coding unit being split from the current coding unit;
• and
• a decoder configured to:
• obtain encoding information indicating an intra prediction mode for the first coding unit among a plurality of intra prediction modes, the plurality of intra prediction modes including directional modes and non-directional modes, and
• when the second coding unit is decoded prior to the first coding unit and a first mode among a plurality of intra prediction modes is used for prediction on the first coding unit, obtain a predicted sample in the first coding unit using a left sample, a bottom-left sample, a right sample, a bottom-right sample and a upper sample,
• wherein the right sample and the bottom-right sample are located in the second coding unit adjacent to the first coding unit,
• the left sample, the bottom-left sample and the upper sample are located in coding units adjacent to the first coding unit, the coding units being decoded prior to the first coding unit.